Patent Publication Number: US-11649053-B2

Title: Hexagonal ring wing aerial vehicle

Description:
PRIORITY CLAIM 
     This application is a continuation of and claims priority to U.S. patent application Ser. No. 16/682,638, filed Nov. 13, 2019, which is a divisional of and claims priority to U.S. patent application Ser. No. 15/435,121, now U.S. Pat. No. 10,518,880, filed Feb. 16, 2017, the contents of each of which are herein incorporated by reference in their entirety. 
    
    
     BACKGROUND 
     Unmanned vehicles, such as unmanned aerial vehicles (“UAV”), ground and water based automated vehicles, are continuing to increase in use. For example, UAVs are often used by hobbyists to obtain aerial images of buildings, landscapes, etc. Likewise, unmanned ground based units are often used in materials handling facilities to autonomously transport inventory within the facility. While there are many beneficial uses of these vehicles, they also have many drawbacks. For example, due to current design limitations, unmanned aerial vehicles are typically designed for either agility or efficiency, but not both. Likewise, aerial vehicles are designed to only operate with four degrees of freedom—pitch, yaw, roll, and heave. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIGS.  1 - 4    illustrate various views of an aerial vehicle with a substantially circular shaped ring wing, in accordance with disclosed implementations. 
         FIGS.  5 - 8    illustrate various views of an aerial vehicle with a substantially hexagonal shaped ring wing, in accordance with disclosed implementations. 
         FIG.  9    is a flow diagram illustrating an example maneuverability process, in accordance with disclosed implementations. 
         FIG.  10    is a flow diagram illustrating an example transition from vertical flight to horizontal flight process, in accordance with disclosed implementations. 
         FIG.  11    is a flow diagram illustrating an example transition from horizontal flight to vertical flight process, in accordance with disclosed implementations. 
         FIG.  12    illustrates an example flight transition from a vertical takeoff to horizontal flight, in accordance with disclosed implementations. 
         FIG.  13    illustrates an example flight transition from a horizontal flight to a vertical landing, in accordance with disclosed implementations. 
         FIG.  14    is a diagram of the propulsion mechanisms of the aerial vehicle illustrated in  FIGS.  1 - 13    with thrust vectors to cause the aerial vehicle to surge in the X direction, when the aerial vehicle is in a vertical takeoff and landing orientation, in accordance with disclosed implementations. 
         FIG.  15    is a diagram of the propulsion mechanisms of the aerial vehicle illustrated in  FIGS.  1 - 13    with thrust vectors to cause the aerial vehicle to sway in the Y direction, when the aerial vehicle is in a vertical takeoff and landing orientation, in accordance with disclosed implementations. 
         FIG.  16    is a diagram of the propulsion mechanisms of the aerial vehicle illustrated in  FIGS.  1 - 13    with thrust vectors to cause the aerial vehicle to hover or heave in the Z direction, when the aerial vehicle is in a vertical takeoff and landing orientation, in accordance with disclosed implementations. 
         FIG.  17    is a diagram of the propulsion mechanisms of the aerial vehicle illustrated in  FIGS.  1 - 13    with thrust vectors to cause the aerial vehicle to pitch, when the aerial vehicle is in a vertical takeoff and landing orientation, in accordance with disclosed implementations. 
         FIG.  18    is a diagram of the propulsion mechanisms of the aerial vehicle illustrated in  FIGS.  1 - 13    with thrust vectors to cause the aerial vehicle to yaw, when the aerial vehicle is in a vertical takeoff and landing orientation, in accordance with disclosed implementations. 
         FIG.  19    is a diagram of the propulsion mechanisms of the aerial vehicle illustrated in  FIGS.  1 - 13    with thrust vectors to cause the aerial vehicle to roll, when the aerial vehicle is in a vertical takeoff and landing orientation, in accordance with disclosed implementations. 
         FIG.  20    is a block diagram illustrating various components of an unmanned aerial vehicle control system, in accordance with disclosed implementations. 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure describes aerial vehicles, such as UAVs (e.g., quad-copters, hex-copters, hepta-copters, octa-copters) that can operate in a vertical takeoff and landing (VTOL) orientation or in a horizontal flight orientation. Likewise, when the aerial vehicle is in a VTOL orientation it can transition independently in any of the six degrees of freedom. Specifically, as described herein, the aerial vehicles may efficiently rotate in any of the three degrees of freedom rotation (pitch, yaw, and roll) and/or any of the three degrees of freedom translation (surge, heave, and sway). For example, the aerial vehicle may include six propulsion mechanisms that are oriented at different angles and therefore, together, can provide thrust in the vertical direction and/or the horizontal direction when the aerial vehicle is in a VTOL orientation. 
     As discussed further below, a ring wing is included on the aerial vehicle that surrounds the propulsion mechanisms of the aerial vehicle and provides both protection around the propulsion mechanisms and lift when the aerial vehicle is in the horizontal flight orientation and navigating in a substantially horizontal direction. 
     As used herein, a “materials handling facility” may include, but is not limited to, warehouses, distribution centers, cross-docking facilities, order fulfillment facilities, packaging facilities, shipping facilities, rental facilities, libraries, retail stores, wholesale stores, museums, or other facilities or combinations of facilities for performing one or more functions of materials (inventory) handling. A “delivery location,” as used herein, refers to any location at which one or more inventory items (also referred to herein as a payload) may be delivered. For example, the delivery location may be a person&#39;s residence, a place of business, a location within a materials handling facility (e.g., packing station, inventory storage), or any location where a user or inventory is located, etc. Inventory or items may be any physical goods that can be transported using an aerial vehicle. For example, an item carried by a payload of an aerial vehicle discussed herein may be ordered by a customer of an electronic commerce website and aerially delivered by the aerial vehicle to a delivery location. 
       FIG.  1    illustrates a view of an aerial vehicle  100  with a ring wing that is substantially cylindrical in shape and that surrounds a plurality of propulsion mechanisms, in accordance with disclosed implementations. The aerial vehicle  100  includes six motors  101 - 1 ,  101 - 2 ,  101 - 3 ,  101 - 4 ,  101 - 5 , and  101 - 6  and corresponding propellers  104 - 1 ,  104 - 2 ,  104 - 3 ,  104 - 4 ,  104 - 5 , and  104 - 6  spaced about the fuselage  110  of the aerial vehicle  100 . The propellers  104  may be any form of propeller (e.g., graphite, carbon fiber) and of any size. For example, the propellers may be 10 inch-12-inch diameter carbon fiber propellers. 
     The form and/or size of some of the propellers may be different than other propellers. Likewise, the motors  101  may be any form of motor, such as a DC brushless motor, and may be of a size sufficient to rotate the corresponding propeller. Likewise, in some implementations, the size and/or type of some of the motors  101  may be different than other motors  101 . In some implementations, the motors may be rotated in either direction such that the force generated by the propellers may be either a positive force, when rotating in a first direction, or a negative force, when rotating in the second direction. Alternatively, or in addition thereto, the pitch of the blades of a propeller may be variable. By varying the pitch of the blades, the force generated by the propeller may be altered to either be in a positive direction or a negative direction. Still further, in some implementations, the pitch of the blades may be adjusted such that they are aligned with the direction of travel and thus provide no drag if they are not rotating. 
     Each pair of motors  101  and corresponding propellers  104  will be referred to herein collectively as a propulsion mechanism  102 , such as propulsion mechanisms  102 - 1 ,  102 - 2 ,  102 - 3 ,  102 - 4 ,  102 - 5 , and  102 - 6 . Likewise, while the example illustrated in  FIG.  1    describes the propulsion mechanisms  102  as including motors  101  and propellers  104 , in other implementations, other forms of propulsion may be utilized as the propulsion mechanisms  102 . For example, one or more of the propulsion mechanisms  102  of the aerial vehicle  100  may utilize fans, jets, turbojets, turbo fans, jet engines, and/or the like to maneuver the aerial vehicle. Generally described, a propulsion mechanism  102 , as used herein, includes any form of propulsion mechanism that is capable of generating a force sufficient to maneuver the aerial vehicle, alone and/or in combination with other propulsion mechanisms. Furthermore, in selected implementations, propulsion mechanisms (e.g.,  102 - 1 ,  102 - 2 ,  102 - 3 ,  102 - 4 ,  102 - 5 , and  102 - 6 ) may be configured such that their individual orientations may be dynamically modified (e.g., change from vertical to horizontal flight orientation) or any position therebetween. 
     Likewise, while the examples herein describe the propulsion mechanisms being able to generate force in either direction, in some implementations, the propulsion mechanisms may only generate force in a single direction. However, the orientation of the propulsion mechanism may be adjusted so that the force can be oriented in a positive direction, a negative direction, and/or any other direction. 
     The aerial vehicle  100  also includes a ring wing  107  having a substantially cylindrical shape that extends around and forms the perimeter of the aerial vehicle  100 . In the illustrated example, the ring wing is substantially circular in shape and tapers toward the bottom of the aerial vehicle. The ring wing  107  has an airfoil shape to produce lift when the aerial vehicle is oriented as illustrated in  FIG.  1    and moving in a direction that is substantially horizontal. As illustrated, and discussed further below, the ring wing is positioned at an angle with respect to the fuselage  110  such that the lower part of the ring wing acts as a front wing as it is toward the front of the aerial vehicle when oriented as shown and moving in a horizontal direction. The top of the ring wing, which has a longer chord length than the bottom portion of the ring wing  107 , is farther back and thus acts as a rear wing. 
     The ring wing is secured to the fuselage  110  by motor arms  105 . In the illustrated example, each of motors arms  105 - 1 ,  105 - 2 ,  105 - 3 ,  105 - 4 ,  105 - 5 , and  105 - 6  are coupled to the fuselage  110  at one end, extend from the fuselage  110  and couple to the ring wing  107  at a second end, thereby securing the ring wing  107  to the fuselage  110 . 
     The fuselage  110 , motor arms  105 , and ring wing  107  of the aerial vehicle  100  may be formed of any one or more suitable materials, such as graphite, carbon fiber, and/or aluminum. 
     Each of the propulsion mechanisms  102  are coupled to a respective motor arm  105  such that the propulsion mechanism  102  is substantially contained within the perimeter ring wing  107 . For example, propulsion mechanism  102 - 1  is coupled to motor arm  105 - 1 , propulsion mechanism  102 - 2  is coupled to motor arm  105 - 2 , propulsion mechanism  102 - 3  is coupled to motor arm  105 - 3 , propulsion mechanism  102 - 4  is coupled to motor arm  105 - 4 , propulsion mechanism  102 - 5  is coupled to motor arm  105 - 5 , and propulsion mechanism  102 - 6  is coupled to motor arm  105 - 6 . In the illustrated example, each propulsion mechanism  102  is coupled at an approximate mid-point of the respective motor arm  105  between the fuselage  110  and the ring wing  107 . In other implementations, the propulsion mechanisms may be coupled at other locations along the motor arm. Likewise, in some implementations, some of the propulsion mechanisms may be coupled to a mid-point of the motor arm and some of the propulsion mechanisms may be coupled at other locations along respective motor arms (e.g., closer toward the fuselage  110  or closer toward the ring wing  107 ). 
     As illustrated, the propulsion mechanisms  102  may be oriented at different angles with respect to each other. For example, propulsion mechanisms  102 - 2  and  102 - 5  are aligned with the fuselage  110  such that the force generated by each of propulsion mechanisms  102 - 2  and  102 - 5  is in-line or in the same direction or orientation as the fuselage. In the illustrated example, the aerial vehicle  100  is oriented for horizontal flight such that the fuselage is oriented horizontally in the direction of travel. In such an orientation, the propulsion mechanisms  102 - 2  and  102 - 5  provide horizontal forces, also referred to herein as thrusting forces, and act as thrusting propulsion mechanisms. 
     In comparison to propulsion mechanisms  102 - 2  and  102 - 5 , each of propulsion mechanisms  102 - 1 ,  102 - 3 ,  102 - 4 , and  102 - 6  are offset or angled with respect to the orientation of the fuselage  110 . When the aerial vehicle  100  is oriented horizontally as shown in  FIG.  1    for horizontal flight, the propulsion mechanisms  102 - 1 ,  102 - 3 ,  102 - 4 , and  102 - 6  may be used as propulsion mechanisms, providing thrust in a non-horizontal direction to cause the aerial vehicle to pitch, yaw, roll, heave and/or sway. In other implementations, during horizontal flight, the propulsion mechanisms  102 - 1 ,  102 - 3 ,  102 - 4 , and  102 - 6  may be disabled such that they do not produce any forces and the aerial vehicle  100  may be propelled aerially in a horizontal direction as a result of the lifting force from the aerodynamic shape of the ring wing  107  and the horizontal thrust produced by the thrusting propulsion mechanisms  102 - 2  and  102 - 5 . 
     The angle of orientation of each of the propulsion mechanisms  102 - 1 ,  102 - 3 ,  102 - 4 , and  102 - 6  may vary for different implementations. Likewise, in some implementations, the offset of the propulsion mechanisms  102 - 1 ,  102 - 3 ,  102 - 4 , and  102 - 6  may each be the same, with some oriented in one direction and some oriented in another direction, may each be oriented different amounts, and/or in different directions. 
     In the illustrated example of  FIG.  1   , each propulsion mechanism  102 - 1 ,  102 - 2 ,  102 - 3 ,  102 - 4 ,  102 - 5 , and  102 - 6  may be oriented approximately thirty degrees with respect to the position of each respective motor arm  105 - 1 ,  105 - 2 ,  105 - 3 ,  105 - 4 ,  105 - 5 , and  105 - 6 . In addition, the direction of orientation of the propulsion mechanisms is such that pairs of propulsion mechanisms are oriented toward one another. For example, propulsion mechanism  102 - 1  is oriented approximately thirty degrees toward propulsion mechanism  102 - 6 . Likewise, propulsion mechanism  102 - 2  is oriented approximately thirty degrees in a second direction about the third motor arm  105 - 2  and oriented toward propulsion mechanism  102 - 3 . Finally, propulsion mechanism  102 - 4  is oriented approximately thirty degrees in the first direction about the fourth motor arm  105 - 4  and toward propulsion mechanism  102 - 5 . As illustrated, propulsion mechanisms  102 - 2  and  102 - 5 , which are on opposing sides of the fuselage  110 , are aligned and oriented a same first direction (in this example, horizontal). Propulsion mechanisms  102 - 3  and  102 - 6 , which are on opposing sides of the fuselage  110 , are aligned and oriented in a same second direction, which is angled compared to the first direction. Propulsion mechanisms  102 - 1  and  102 - 4 , which are on opposing sides of the fuselage  110 , are aligned and oriented a same third direction, which is angled compared to the first direction and the second direction. 
       FIG.  2    illustrates a side view of the aerial vehicle  200  oriented for vertical takeoff and landing (VTOL), in accordance with disclosed implementations. The aerial vehicle  200  corresponds to the aerial vehicle  100  discussed above with respect to  FIG.  1   . When oriented as illustrated in  FIG.  2   , the aerial vehicle may maneuver in any of the six degrees of freedom (pitch, yaw, roll, heave, surge, and sway), thereby enabling VTOL and high maneuverability. 
     As illustrated, when the aerial vehicle is oriented for VTOL, the motor arms, such as motor arms  205 - 1 ,  205 - 2 , and  205 - 3 , and the ring wing  207  are aligned approximately horizontally and in the same plane. In this orientation, each of the propulsion mechanisms are offset or angled with respect to the horizontal and/or vertical direction. As such, each propulsion mechanism  202 , when generating a force, generates a force that includes both a horizontal component and a vertical component. In the illustrated example, each propulsion mechanism is angled approximately thirty degrees with respect to vertical. Likewise, as discussed above, adjacent propulsion mechanisms are angled in opposing directions to form pairs of propulsion mechanisms. For example, propulsion mechanism  202 - 2  is oriented toward propulsion mechanism  202 - 3 . As discussed further below, angling adjacent propulsion mechanisms toward one another to form pairs of propulsion mechanisms allows horizontal forces from each propulsion mechanism to cancel out such that the pair of propulsion mechanisms can produce a vertical force. Likewise, if one of the propulsion mechanisms of a pair of propulsion mechanisms is producing a larger force than the other propulsion mechanism of the pair, a net horizontal force will result from the pair of propulsion mechanisms. Accordingly, when the aerial vehicle  200  is oriented for VTOL with angled propulsion mechanisms, as illustrated in  FIG.  2   , the aerial vehicle can move independently in any of the six degrees of freedom. For example, if the aerial vehicle is to surge in the X direction, it can do so by altering the forces produced by the propulsion mechanisms to generate a net horizontal force in the X direction without having to pitch forward to enable a surge in the X direction. 
     To enable the fuselage to be oriented horizontally with an offset ring wing  207  during horizontal flight, as illustrated in  FIG.  1   , the fuselage is rotated at an angle when the aerial vehicle  200  is oriented for VTOL, as illustrated in  FIG.  2   . In this example, the fuselage  210  is angled at approximately thirty degrees from vertical. In other implementations, the amount of rotation from vertical may be greater or less depending on the amount of offset desired for the ring wing  207  when the aerial vehicle  200  is oriented for horizontal flight. 
     The aerial vehicle may also include one or more landing gears  203  that are extendable to a landing position, as illustrated in  FIG.  2   . During flight, the landing gear  203  may be retracted into the interior of the ring wing  207  and/or may be rotated up and remain along the trailing edge of the ring wing. In still other examples, the landing gear may be permanently affixed. 
     The fuselage  210  may be used to store one or more components of the aerial vehicle, such as the aerial vehicle control system  214 , power module  206 , and/or a payload  212  that is transported by the aerial vehicle. The aerial vehicle control system is discussed further below. The power module(s)  206  may be removably mounted to the aerial vehicle  200 . The power module(s)  206  for the aerial vehicle may be, for example, in the form of battery power, solar power, gas power, super capacitor, fuel cell, alternative power generation source, or a combination thereof. The power module(s)  206  are coupled to and provide power for the aerial vehicle control system  214 , the propulsion mechanisms  202 , and the payload engagement module  210 - 1 . 
     In some implementations, one or more of the power modules may be configured such that it can be autonomously removed and/or replaced with another power module. For example, when the aerial vehicle lands at a delivery location, relay location and/or materials handling facility, the aerial vehicle may engage with a charging member at the location that will recharge the power module. 
     The payload  212  may be any payload that is to be transported by the aerial vehicle. In some implementations, the aerial vehicle may be used to aerially deliver items ordered from customers for aerial delivery and the payload may include one or more customer ordered items. For example, a customer may order an item from an electronic commerce website and the item may be delivered to a customer specified delivery location using the aerial vehicle  200 . 
     In some implementations, the fuselage  210  may include a payload engagement module  210 - 1 . For example, the payload engagement module  210 - 1  may be a hinged portion of the fuselage  210  that can rotate between an open position, in which the interior of the fuselage is accessible so that the payload  212  may be added to or removed from the fuselage, and a closed position, as illustrated in  FIG.  2   , so that the payload  212  is secured within the interior of the fuselage. 
       FIG.  3    is a side view of an aerial vehicle  300  with a ring wing  307 , in accordance with disclosed implementations. The aerial vehicle  300  corresponds to the aerial vehicle  100  discussed in  FIG.  1    and aerial vehicle  200  discussed in  FIG.  2   . As illustrated, when the aerial vehicle is oriented for horizontal flight, as illustrated in  FIG.  3   , the fuselage  310  is oriented horizontally and two of the propulsion mechanisms, propulsion mechanism  302 - 2  and the propulsion mechanism on the opposing side of the fuselage and illustrated in  FIG.  1   , are oriented to produce thrust in a substantially horizontal direction. In comparison, the other propulsion mechanisms, such as propulsion mechanisms  302 - 1  and  302 - 3 , are not oriented to produce forces in substantially the horizontal direction. During horizontal flight, the propulsion mechanisms, such as propulsion mechanisms  302 - 1  and  302 - 3 , may be disabled and/or used to produce maneuverability forces that will cause the aerial vehicle to pitch, yaw, and/or roll as it aerially navigates in a substantially horizontal direction. In some implementations, the propulsion mechanisms that are not aligned to produce substantially horizontal forces may be allowed to freely rotate in the wind and energy produced from the rotation may be used to charge the power module of the aerial vehicle  300 . 
     The ring wing  307  is angled such that the lower portion  307 - 2  of the ring wing is positioned ahead of the upper portion  307 - 1  of the ring wing  307 . Because the leading wing, lower portion  307 - 2  produces a much higher lift per square inch than the rear wing, upper portion  307 - 1 , and the chord length of the lower portion  307 - 2  is less than the chord length of the upper portion  307 - 1 . Likewise, as illustrated, the upper portion  307 - 1  of the ring wing has a different camber than the lower portion  307 - 2 . The chord length and camber transition from that illustrated along the upper portion  307 - 1  to the lower portion  307 - 2 . While the sides of the ring wing provide some lift, at the midpoint of each side, there is minimal lift produced by the ring wing  307 . 
     In addition to providing lift, the ring wing  307  provides a protective barrier or shroud that surrounds the propulsion mechanisms of the aerial vehicle  300 . The protective barrier of the ring wing  307  increases the safety of the aerial vehicle. For example, if the aerial vehicle comes into contact with another object, there is a higher probability that the object will contact the ring wing, rather than a propulsion mechanism. 
       FIG.  4    is a front-on view of an aerial vehicle  400  with a ring wing  407 , according to disclosed implementations. The aerial vehicle  400  corresponds to aerial vehicle  100  of  FIG.  1   , aerial vehicle  200  of  FIG.  2   , and aerial vehicle  300  of  FIG.  3   . As discussed above with respect to  FIG.  3   , when the aerial vehicle is oriented for horizontal flight, as illustrated in  FIGS.  3  and  4   , the fuselage  410  is oriented in the direction of travel, the ring wing  407  is oriented in the direction of travel such that it will produce a lifting force, and propulsion mechanisms  402 - 2  and  402 - 5 , which are on opposing sides of the fuselage  410 , are aligned to produce forces in the substantially horizontal direction to propel or thrust the aerial vehicle horizontally. The other propulsion mechanisms  402 - 1 ,  402 - 3 ,  402 - 4 , and  402 - 6  are offset and may be disabled, used to produce maneuverability forces, and/or allowed to freely rotate and produce energy that is used to charge a power module of the aerial vehicle  400 . By increasing the thrust produced by each of the propulsion mechanisms  402 - 2  and  402 - 5 , the horizontal speed of the aerial vehicle increases. Likewise, the lifting force from the ring wing  407  also increases. In some implementations, as discussed further below, one or more ailerons may be included on the surface of the ring wing and used to control the aerial navigation of the aerial vehicle during horizontal flight. 
     As discussed below, to transition the aerial vehicle from a VTOL orientation, as illustrated in  FIG.  2   , to a horizontal flight orientation, as illustrated in  FIGS.  3  and  4   , forces generated by each of the propulsion mechanisms  402  will cause the aerial vehicle to pitch forward and increase in speed in the horizontal direction. As the horizontal speed increases and the pitch increases, the lifting force produced by the airfoil shape of the ring wing will increase which will further cause the aerial vehicle to pitch into the horizontal flight orientation and allow the aerial vehicle to remain airborne. 
     In contrast, as discussed below, when the aerial vehicle is to transition from a horizontal flight orientation to a VTOL orientation, forces from the propulsion mechanisms may cause the aerial vehicle to decrease pitch and reduce horizontal speed. As the pitch of the aerial vehicle decreases, the lift produced by the airfoil shape of the ring wing decreases and the thrust produced by each of the six propulsion mechanisms  402  are utilized to maintain flight of the aerial vehicle  400 . 
     As illustrated in  FIGS.  1 - 4   , each of the propulsion mechanisms  402  are positioned in approximately the same plane that is substantially aligned with the ring wing. Likewise, each propulsion mechanism  402  is spaced approximately sixty degrees from each other around the fuselage  410 , such that the propulsion mechanisms are positioned at approximately equal distances with respect to one another and around the fuselage  410  of the aerial vehicle  400 . For example, the second propulsion mechanism  402 - 2  and the fifth propulsion mechanism  402 - 5  may each be positioned along the X axis. The third propulsion mechanism  402 - 3  may be positioned at approximately sixty degrees from the X axis and the fourth propulsion mechanism  402 - 4  may be positioned approximately one-hundred and twenty degrees from the X axis. Likewise, the first propulsion mechanism  402 - 1  and the sixth propulsion mechanism  402 - 6  may likewise be positioned approximately sixty and one-hundred and twenty degrees from the X axis in the negative direction. 
     In other implementations, the spacing between the propulsion mechanisms may be different. For example, propulsion mechanisms  402 - 1 ,  402 - 3 , and  402 - 5 , which are oriented in the first direction, may each be approximately equally spaced 120 degrees apart and propulsion mechanisms  402 - 2 ,  402 - 4 , and  402 - 6 , which are oriented in the second direction, may also be approximately equally spaced 120 degrees apart. However, the spacing between propulsion mechanisms oriented in the first direction and propulsion mechanisms oriented in the second direction may not be equal. For example, the propulsion mechanisms  402 - 1 ,  402 - 3 , and  402 - 5  oriented in the first direction, may be positioned at approximately zero degrees, approximately 120 degrees, and approximately 240 degrees around the perimeter of the aerial vehicle with respect to the X axis, and the propulsion mechanisms  402 - 2 ,  402 - 4 , and  402 - 6 , oriented in the second direction, may be positioned at approximately 10 degrees, approximately 130 degrees, and approximately 250 degrees around the perimeter of the aerial vehicle  400  with respect to the X axis. 
     In other implementations, the propulsion mechanisms may have other alignments. Likewise, in other implementations, there may be fewer or additional propulsion mechanisms. Likewise, in some implementations, the propulsion mechanisms may not all be aligned in the same plane and/or the ring wing may be in a different plane than some or all of the propulsion mechanisms. 
     While the examples discussed above and illustrated in  FIGS.  1 - 4    discuss rotating the propulsion mechanisms approximately thirty degrees about each respective motor arm and that the ring wing is offset approximately thirty degrees with respect to the fuselage, in other implementations, the orientation of the propulsion mechanisms and/or the ring wing may be greater or less than thirty degrees and the angle of the ring wing may be different than the angle of one or more propulsion mechanisms. In some implementations, if maneuverability of the aerial vehicle when the aerial vehicle is in VTOL orientation is of higher importance, the orientation of the propulsion mechanisms may be higher than thirty degrees. For example, each of the propulsion mechanisms may be oriented approximately forty-five degrees about each respective motor arm, in either the first or second direction. In comparison, if lifting force of the aerial vehicle when the aerial vehicle is in the VTOL orientation is of higher importance, the orientation of the propulsion mechanisms may be less than thirty degrees. For example, each propulsion mechanism may be oriented approximately ten degrees from a vertical orientation about each respective motor arm. 
     In some implementations, the orientations of some propulsion mechanisms may be different than other propulsion mechanisms. For example, propulsion mechanisms  402 - 1 ,  402 - 3 , and  402 - 5  may each be oriented approximately fifteen degrees in the first direction and propulsion mechanisms  402 - 2 ,  402 - 4 , and  402 - 6  may be oriented approximately twenty-five degrees in the second direction. In still other examples, pairs of propulsion mechanisms may have different orientations than other pairs of propulsion mechanisms. For example, propulsion mechanisms  402 - 1  and  402 - 6  may each be oriented approximately thirty degrees in the first direction and second direction, respectively, toward one another, propulsion mechanisms  402 - 3  and  402 - 2  may each be oriented approximately forty-five degrees in the first direction and second direction, respectively, toward one another, and propulsion mechanisms  402 - 5  and  402 - 4  may each be oriented approximately forty-five degrees in the first direction and second direction, respectively, toward one another. 
     As discussed below, by orienting propulsion mechanisms partially toward one another in pairs, as illustrated, the lateral or horizontal forces generated by the pairs of propulsion mechanisms, when producing the same amount of force, will cancel out such that the sum of the forces from the pair is only in a substantially vertical direction (Z direction), when the aerial vehicle is in the VTOL orientation. Likewise, as discussed below, if one propulsion mechanism of the pair produces a force larger than a second propulsion mechanism, a lateral or horizontal force will result in the X direction and/or the Y direction, when the aerial vehicle is in the VTOL orientation. A horizontal force produced from one or more of the pairs of propulsion mechanisms enables the aerial vehicle to translate in a horizontal direction and/or yaw without altering the pitch of the aerial vehicle, when the aerial vehicle is in the VTOL orientation. Producing lateral forces by multiple pairs of propulsion mechanisms  402  enables the aerial vehicle  400  to operate independently in any of the six degrees of freedom (surge, sway, heave, pitch, yaw, and roll). As a result, the stability and maneuverability of the aerial vehicle  400  is increased. 
     While the implementations illustrated in  FIGS.  1 - 4    include six arms that extend radially from a central portion of the aerial vehicle and are coupled to the ring wing, in other implementations, there may be fewer or additional arms. For example, the aerial vehicle may include support arms that extend between the arms  105  and provide additional support to the aerial vehicle. As another example, not all of the motor arms may extend to and couple with the ring wing. 
       FIG.  5    illustrates a view of an aerial vehicle  500  with a ring wing that is substantially hexagonal in shape and that surrounds a plurality of propulsion mechanisms, according to disclosed implementations. Similar to the aerial vehicle discussed with respect to  FIGS.  1 - 4   , the aerial vehicle  500  includes six propulsion mechanisms  502 - 1 ,  502 - 2 ,  502 - 3 ,  502 - 4 ,  502 - 5 , and  502 - 6  spaced about the fuselage  510  of the aerial vehicle  500 . As discussed above, while the propulsion mechanisms  502  may include motors and propellers, in other implementations, other forms of propulsion may be utilized as the propulsion mechanisms  502 . For example, one or more of the propulsion mechanisms  502  of the aerial vehicle  500  may utilize fans, jets, turbojets, turbo fans, jet engines, and/or the like to maneuver the aerial vehicle. Generally described, a propulsion mechanism  502 , as used herein, includes any form of propulsion mechanism that is capable of generating a force sufficient to maneuver the aerial vehicle, alone and/or in combination with other propulsion mechanisms. Furthermore, in selected implementations, propulsion mechanisms (e.g.,  502 - 1 ,  502 - 2 ,  502 - 3 ,  502 - 4 ,  502 - 5 , and  502 - 6 ) may be configured such that their individual orientations may be dynamically modified (e.g., change from vertical to horizontal flight orientation) or any position therebetween. 
     Likewise, while the examples herein describe the propulsion mechanisms being able to generate force in either direction, in some implementations, the propulsion mechanisms may only generate force in a single direction. However, the orientation of the propulsion mechanism may be adjusted so that the force can be oriented in a positive direction, a negative direction, and/or any other direction. 
     In this implementation, the aerial vehicle  500  also includes a ring wing  507  having a substantially hexagonal shape that extends around and forms the perimeter of the aerial vehicle  500 . In the illustrated example, the ring wing has six segments  507 - 1 ,  507 - 2 ,  507 - 3 ,  507 - 4 ,  507 - 5 , and  507 - 6  that are joined at adjacent ends to form the ring wing  507  around the aerial vehicle  500 . Each segment of the ring wing  507  has an airfoil shape to produce lift when the aerial vehicle is oriented as illustrated in  FIG.  5    and moving in a direction that is substantially horizontal. As illustrated, and discussed further below, the ring wing is positioned at an angle with respect to the fuselage  510  such that the lower segment  507 - 2  of the ring wing acts as a front wing as it is toward the front of the aerial vehicle when oriented as shown and moving in a horizontal direction. The upper segment  507 - 1  of the ring wing, which has a longer chord length than the lower segment  507 - 2  of the ring wing  507 , is farther back and thus acts as a rear wing. 
     The ring wing  507  is secured to the fuselage  510  by motor arms  505 . In this example, all six motor arms  505 - 1 ,  505 - 2 ,  505 - 3 ,  505 - 4 ,  505 - 5 , and  505 - 6  are coupled to the fuselage at one end, extend from the fuselage  510  and couple to the ring wing  507  at a second end, thereby securing the ring wing  507  to the fuselage. In other implementations, less than all of the motor arms may extend from the fuselage  510  and couple to the ring wing  507 . For example, motor arms  505 - 2  and  505 - 5  may be coupled to the fuselage  510  at one end and extend outward from the fuselage but not couple to the ring wing  507 . 
     In some implementations, the aerial vehicle may also include one or more stabilizer fins  520  that extend from the fuselage  510  to the ring wing  507 . The stabilizer fin  520  may also have an airfoil shape. In the illustrated example, the stabilizer fin  520  extends vertically from the fuselage  510  to the ring wing  507 . In other implementations, the stabilizer fin may be at other positions. For example, the stabilizer fin may extend downward from the fuselage between motor arm  505 - 1  and motor arm  505 - 6 . 
     In general, one or more stabilizer fins may extend from the fuselage  510 , between any two motor arms  505  and couple to an interior of the ring wing  507 . For example, stabilizer fin  520  may extend upward between motor arms  505 - 3  and  505 - 4 , a second stabilizer fin may extend from the fuselage and between motor arms  505 - 5  and  505 - 6 , and a third stabilizer fin may extend from the fuselage and between motor arms  505 - 1  and  505 - 2 . 
     Likewise, while the illustrated example shows the stabilizer fin extending from the fuselage  510  at one end and coupling to the interior of the ring wing  507  at a second end, in other implementations, one or more of the stabilizer fin(s) may extend from the fuselage and not couple to the ring wing or may extend from the ring wing and not couple to the fuselage. In some implementations, one or more stabilizer fins may extend from the exterior of the ring wing  507 , one or more stabilizer fins may extend from the interior of the ring wing  507 , one or more stabilizer fins may extend from the fuselage  510 , and/or one or more stabilizer fins may extend from the fuselage  510  and couple to the interior of the ring wing  507 . 
     The fuselage  510 , motor arms  505 , stabilizer fin  520 , and ring wing  507  of the aerial vehicle  500  may be formed of any one or more suitable materials, such as graphite, carbon fiber, and/or aluminum. 
     Each of the propulsion mechanisms  502  are coupled to a respective motor arm  505  such that the propulsion mechanism  502  is substantially contained within the perimeter ring wing  507 . For example, propulsion mechanism  502 - 1  is coupled to motor arm  505 - 1 , propulsion mechanism  502 - 2  is coupled to motor arm  505 - 2 , propulsion mechanism  502 - 3  is coupled to motor arm  505 - 3 , propulsion mechanism  502 - 4  is coupled to motor arm  505 - 4 , propulsion mechanism  502 - 5  is coupled to motor arm  505 - 5 , and propulsion mechanism  502 - 6  is coupled to motor arm  505 - 6 . In the illustrated example, each propulsion mechanism  502 - 1 ,  502 - 3 ,  502 - 4 , and  502 - 6  is coupled at an approximate mid-point of the respective motor arm  505 - 1 ,  505 - 3 ,  505 - 4 , and  505 - 6  between the fuselage  510  and the ring wing  507 . In comparison, propulsion mechanisms  502 - 2  and  502 - 5  are coupled toward an end of the respective motor arm  505 - 2  and  505 - 5 . In other implementations, the propulsion mechanisms may be coupled at other locations along the motor arm. Likewise, in some implementations, some of the propulsion mechanisms may be coupled to a mid-point of the motor arm and some of the propulsion mechanisms may be coupled at other locations along respective motor arms (e.g., closer toward the fuselage  510  or closer toward the ring wing  507 ). 
     As illustrated, the propulsion mechanisms  502  may be oriented at different angles with respect to each other. For example, propulsion mechanisms  502 - 2  and  502 - 5  are aligned with the fuselage  510  such that the force generated by each of propulsion mechanisms  502 - 2  and  502 - 5  is in-line or in the same direction or orientation as the fuselage. In the illustrated example, the aerial vehicle  500  is oriented for horizontal flight such that the fuselage is oriented horizontally in the direction of travel. In such an orientation, the propulsion mechanisms  502 - 2  and  502 - 5  provide horizontal forces, also referred to herein as thrusting forces and act as thrusting propulsion mechanisms. 
     In comparison to propulsion mechanisms  502 - 2  and  502 - 5 , each of propulsion mechanisms  502 - 1 ,  502 - 3 ,  502 - 4 , and  502 - 6  are offset or angled with respect to the orientation of the fuselage  510 . When the aerial vehicle  500  is oriented horizontally as shown in  FIG.  5    for horizontal flight, the propulsion mechanisms  502 - 1 ,  502 - 3 ,  502 - 4 , and  502 - 6  may be used as propulsion mechanisms, providing thrust in a non-horizontal direction to cause the aerial vehicle to pitch, yaw, roll, heave and/or sway. In other implementations, during horizontal flight, the propulsion mechanisms  502 - 1 ,  502 - 3 ,  502 - 4 , and  502 - 6  may be disabled such that they do not produce any forces and the aerial vehicle  500  may be propelled aerially in a horizontal direction as a result of the lifting force from the aerodynamic shape of the ring wing  507  and the horizontal thrust produced by the thrusting propulsion mechanisms  502 - 2  and  502 - 5 . 
     In some implementations, one or more segments of the ring wing  507  may include ailerons  509  that may be adjusted to control the aerial flight of the aerial vehicle  500 . For example, one or more ailerons  509  may be included on the upper segment  507 - 1  of the ring wing  507  and/or one or more ailerons  509  may be included on the side segments  507 - 4  and/or  507 - 3 . The ailerons  509  may be operable to control the pitch, yaw, and/or roll of the aerial vehicle during horizontal flight when the aerial vehicle  500  is oriented as illustrated in  FIG.  5   . 
     The angle of orientation of each of the propulsion mechanisms  502 - 1 ,  502 - 2 ,  502 - 3 ,  502 - 4 ,  502 - 5 , and  502 - 6  may vary for different implementations. Likewise, in some implementations, the offset of the propulsion mechanisms  502 - 1 ,  502 - 2 ,  502 - 3 ,  502 - 4 ,  502 - 5 , and  502 - 6  may each be the same, with some oriented in one direction and some oriented in another direction, may each be oriented different amounts, and/or in different directions. 
     In the illustrated example of  FIG.  5   , each propulsion mechanism  502 - 1 ,  502 - 2 ,  502 - 3 ,  502 - 4 ,  502 - 5 , and  502 - 6  may be oriented approximately thirty degrees with respect to the position of each respective motor arm  505 - 1 ,  505 - 2 ,  505 - 3 ,  505 - 4 ,  505 - 5 , and  505 - 6 . In addition, the direction of orientation of the propulsion mechanisms is such that pairs of propulsion mechanisms are oriented toward one another. For example, propulsion mechanism  502 - 1  is oriented approximately thirty degrees toward propulsion mechanism  502 - 6 . Likewise, propulsion mechanism  502 - 2  is oriented approximately thirty degrees in a second direction about the second motor arm  505 - 2  and oriented toward propulsion mechanism  502 - 3 . Finally, propulsion mechanism  502 - 4  is oriented approximately thirty degrees in the first direction about the fourth motor arm  505 - 4  and toward propulsion  502 - 5 . As illustrated, propulsion mechanisms  502 - 3  and  502 - 6 , which are on opposing sides of the fuselage  510 , are aligned and oriented in a same first direction (in this example, horizontal). Propulsion mechanisms  502 - 2  and  502 - 5 , which are on opposing sides of the fuselage  510 , are aligned and oriented in a same second direction, which is angled compared to the first direction. Propulsion mechanisms  502 - 1  and  502 - 4 , which are on opposing sides of the fuselage  510 , are aligned and oriented in a same third direction, which is angled compared to the first direction and the second direction. 
       FIG.  6    illustrates a side view of the aerial vehicle  600  oriented for vertical takeoff and landing (VTOL), in accordance with disclosed implementations. The aerial vehicle  600  corresponds to the aerial vehicle  500  discussed above with respect to  FIG.  5   . When oriented as illustrated in  FIG.  6   , the aerial vehicle may maneuver in any of the six degrees of freedom (pitch, yaw, roll, heave, surge, and sway), thereby enabling VTOL and high maneuverability. 
     As illustrated, when the aerial vehicle is oriented for VTOL, the motor arms and the ring wing  607  are aligned approximately horizontally and in the same plane. In this orientation, each of the propulsion mechanisms are offset or angled with respect to the horizontal and/or vertical direction. As such, each propulsion mechanism  602 , when generating a force, generates a force that includes both a horizontal component and a vertical component. In the illustrated example, each propulsion mechanism is angled approximately thirty degrees with respect to vertical. Likewise, as discussed above, adjacent propulsion mechanisms are angled in opposing directions to form pairs of propulsion mechanisms. For example, propulsion mechanism  602 - 2  is oriented toward propulsion mechanism  602 - 3 . As discussed further below, angling adjacent propulsion mechanisms toward one another to form pairs of propulsion mechanisms allows horizontal forces from each propulsion mechanism to cancel out such that the pair of propulsion mechanisms can produce a vertical force. Likewise, if one of the propulsion mechanisms of a pair of propulsion mechanisms is producing a larger force than the other propulsion mechanism of the pair, a net horizontal force will result from the pair of propulsion mechanisms. Accordingly, when the aerial vehicle  600  is oriented for VTOL with angled propulsion mechanisms, as illustrated in  FIG.  6   , the aerial vehicle can move independently in any of the six degrees of freedom. For example, if the aerial vehicle is to surge in the X direction, it can do so by altering the forces produced by the propulsion mechanisms to generate a net horizontal force in the X direction without having to pitch forward to enable a surge in the X direction. 
     To enable the fuselage to be oriented horizontally with an offset ring wing  607  during horizontal flight, as illustrated in  FIG.  5   , the fuselage is rotated at an angle when the aerial vehicle  600  is oriented for VTOL, as illustrated in  FIG.  6   . In this example the fuselage  610  is angled at approximately thirty degrees from vertical. In other implementations, the amount of rotation from vertical may be greater or less depending on the amount of offset desired for the ring wing  607  when the aerial vehicle  600  is oriented for horizontal flight. 
     The aerial vehicle may also include one or more landing gears  603  that are extendable to a landing position, as illustrated in  FIG.  6   . During flight, the landing gear  603  may be retracted into the interior of the ring wing  607  and/or may be rotated up and remain along the trailing edge of the ring wing. In still other examples, the landing gear may be permanently affixed. 
     The fuselage  610  may be used to store one or more components of the aerial vehicle, such as the aerial vehicle control system  614 , power module  606 , and/or a payload  612  that is transported by the aerial vehicle. The aerial vehicle control system is discussed further below. The power module(s)  606  may be removably mounted to the aerial vehicle  600 . The power module(s)  606  for the aerial vehicle may be, for example, in the form of battery power, solar power, gas power, super capacitor, fuel cell, alternative power generation source, or a combination thereof. The power module(s)  606  are coupled to and provide power for the aerial vehicle control system  614 , the propulsion mechanisms  602 , and the payload engagement module  610 - 1 . 
     In some implementations, one or more of the power modules may be configured such that it can be autonomously removed and/or replaced with another power module. For example, when the aerial vehicle lands at a delivery location, relay location and/or materials handling facility, the aerial vehicle may engage with a charging member at the location that will recharge the power module. 
     The payload  612  may be any payload that is to be transported by the aerial vehicle. In some implementations, the aerial vehicle may be used to aerially deliver items ordered from customers for aerial delivery and the payload may include one or more customer ordered items. For example, a customer may order an item from an electronic commerce website and the item may be delivered to a customer specified delivery location using the aerial vehicle  600 . 
     In some implementations, the fuselage  610  may include a payload engagement module  610 - 1 . For example, the payload engagement module  610 - 1  may be a hinged portion of the fuselage  610  that can rotate between an open position, in which the interior of the fuselage is accessible so that the payload  612  may be added to or removed from the fuselage, and a closed position, as illustrated in  FIG.  6   , so that the payload  612  is secured within the interior of the fuselage. 
       FIG.  7    is a side view of an aerial vehicle  700  with a ring wing  707 , in accordance with disclosed implementations. The aerial vehicle  700  corresponds to the aerial vehicle  500  discussed in  FIG.  5    and aerial vehicle  600  discussed in  FIG.  6   . As illustrated, when the aerial vehicle is oriented for horizontal flight, as illustrated in  FIG.  7   , the fuselage  710  is oriented horizontally and two of the propulsion mechanisms, propulsion mechanism  702 - 2  and the propulsion mechanism on the opposing side of the fuselage and illustrated in  FIG.  5   , are oriented to produce thrust in a substantially horizontal direction. In comparison, the other propulsion mechanisms, such as propulsion mechanisms  702 - 1  and  702 - 3  are not oriented to produce forces in substantially the horizontal direction. During horizontal flight, the propulsion mechanisms, such as propulsion mechanism  702 - 1  and  702 - 3  may be disabled and/or used to produce maneuverability forces that will cause the aerial vehicle to pitch, yaw, and/or roll as it aerially navigates in a substantially horizontal direction. In some implementations, the propulsion mechanisms that are not aligned to produce substantially horizontal forces may be allowed to freely rotate in the wind and energy produced from the rotation may be used to charge the power module of the aerial vehicle  700 . 
     The ring wing  707  is angled such that the lower segment  707 - 2  of the ring wing is positioned ahead of the upper segment  707 - 1  of the ring wing  707 . Because the leading wing, lower segment  707 - 2  produces a much higher lift per square inch than the rear wing, upper segment  707 - 1 , the chord length of the lower segment  707 - 2  is less than the chord length of the upper segment  707 - 1 . Likewise, as illustrated, the upper segment  707 - 1  of the ring wing has a different camber than the lower segment  707 - 2 . The chord length and camber transition from that illustrated along the upper segment  707 - 1  to the lower segment  707 - 2 . In implementations that include one or more stabilizer fins, such as stabilizer fin  520  ( FIG.  5   ), the difference between the chord length of the lower segment  707 - 2  and the upper segment  707 - 1  may be less and/or the difference between the camber of the lower segment  707 - 2  and the upper segment  707 - 1  may be less. 
     While the side segments, such as side segment  707 - 4  and segment  707 - 6  of the ring wing provide some lift, at the midpoint  708  of each side segment there is minimal lift produced by the ring wing  707 . Because there is minimal lift produced at the midpoint  708 , the segments may be tapered to reduce the overall weight of the aerial vehicle. In this example, the side segments, such as side segments  707 - 4  and  707 - 6 , are tapered toward the mid-point but retain some dimension for structural integrity and to operate as a protective barrier around the propulsion mechanisms  702 . While the illustrated examples show both side segments  707 - 4  and  707 - 6  tapering to a smaller end at the midpoint  708 , in other implementations, the taper may be consistent from the larger top segment  707 - 1  to the smaller lower segment  707 - 2 . 
     In addition to providing lift, the ring wing  707  provides a protective barrier or shroud that surrounds the propulsion mechanisms of the aerial vehicle  700 . The protective barrier of the ring wing  707  increases the safety of the aerial vehicle. For example, if the aerial vehicle comes into contact with another object, there is a higher probability that the object will contact the ring wing, rather than a propulsion mechanism. 
       FIG.  8    is a front-on view of an aerial vehicle  800  with a ring wing  807  having a substantially hexagonal shape, according to disclosed implementations. The aerial vehicle  800  corresponds to aerial vehicle  500  of  FIG.  5   , aerial vehicle  600  of  FIG.  6   , and aerial vehicle  700  of  FIG.  7   . As discussed above with respect to  FIG.  7   , when the aerial vehicle is oriented for horizontal flight, as illustrated in  FIGS.  7  and  8   , the fuselage  810  is oriented in the direction of travel, the ring wing  807  is oriented in the direction of travel such that it will produce a lifting force, and propulsion mechanisms  802 - 2  and  802 - 5 , which are on opposing sides of the fuselage  810 , are aligned to produce forces in the substantially horizontal direction to propel or thrust the aerial vehicle horizontally. The other propulsion mechanisms  802 - 1 ,  802 - 3 ,  802 - 4 , and  802 - 6  are offset and may be disabled, used to produce maneuverability forces, and/or allowed to freely rotate and produce energy that is used to charge a power module of the aerial vehicle  800 . By increasing the thrust produced by each of the propulsion mechanisms  802 - 2  and  802 - 5 , the horizontal speed of the aerial vehicle increases. Likewise, the lifting force from the ring wing  807  also increases. In some implementations, one or more ailerons, such as those discussed above with respect to  FIG.  5   , may be included on the surface of the ring wing and used to control the aerial navigation of the aerial vehicle during horizontal flight. Likewise, one or more stabilizer fins  820  may be included to stabilize the aerial vehicle during horizontal flight. 
     In some implementations, the hexagonal shaped ring wing may decrease manufacturing costs, provide for more stable flight, and provide flatter surfaces upon which control elements, such as ailerons, may be included. Likewise, other components may be coupled to the surface of the ring wing. Other components include, but are not limited to, sensors, imaging elements, range finders, identifying markers, navigation components, such as global positioning satellite antennas, antennas, etc. 
     As discussed below, to transition the aerial vehicle from a VTOL orientation, as illustrated in  FIG.  6   , to a horizontal flight orientation, as illustrated in  FIGS.  7  and  8   , forces generated by each of the propulsion mechanisms  802  will cause the aerial vehicle to pitch forward and increase in speed in the horizontal direction. As the horizontal speed increases and the pitch increases, the lifting force produced by the airfoil shape of the ring wing will increase which will further cause the aerial vehicle to pitch into the horizontal flight orientation and allow the aerial vehicle to remain airborne. 
     In contrast, as discussed below, when the aerial vehicle is to transition from a horizontal flight orientation to a VTOL orientation, forces from the propulsion mechanisms may cause the aerial vehicle to decrease pitch and reduce horizontal speed. As the pitch of the aerial vehicle decreases, the lift produced by the airfoil shape of the ring wing decreases and the thrust produced by each of the six propulsion mechanisms  802  are utilized to maintain flight of the aerial vehicle  800 . 
     As illustrated in  FIGS.  5 - 8   , each of the propulsion mechanisms  802  are positioned in approximately the same plane that is substantially aligned with the ring wing. Likewise, each propulsion mechanism  802  is spaced approximately sixty degrees from each other around the fuselage  810 , such that the propulsion mechanisms are positioned at approximately equal distances with respect to one another and around the fuselage  810  of the aerial vehicle  800 . For example, the second propulsion mechanism  802 - 2  and the fifth propulsion mechanism  802 - 5  may each be positioned along the X axis. The third propulsion mechanism  802 - 3  may be positioned at approximately sixty degrees from the X axis and the fourth propulsion mechanism  802 - 4  may be positioned approximately one-hundred and twenty degrees from the X axis. Likewise, the first propulsion mechanism  802 - 1  and the sixth propulsion mechanism  802 - 6  may likewise be positioned approximately sixty and one-hundred and twenty degrees from the X axis in the negative direction. 
     In other implementations, the spacing between the propulsion mechanisms may be different. For example, propulsion mechanisms  802 - 1 ,  802 - 3 , and  802 - 5 , which are oriented in the first direction, may each be approximately equally spaced 120 degrees apart and propulsion mechanisms  802 - 2 ,  802 - 4 , and  802 - 6 , which are oriented in the second direction, may also be approximately equally spaced 120 degrees apart. However, the spacing between propulsion mechanisms oriented in the first direction and propulsion mechanisms oriented in the second direction may not be equal. For example, the propulsion mechanisms  802 - 1 ,  802 - 3 , and  802 - 5 , oriented in the first direction, may be positioned at approximately zero degrees, approximately 120 degrees, and approximately 240 degrees around the perimeter of the aerial vehicle with respect to the X axis, and the propulsion mechanisms  802 - 2 ,  802 - 4 , and  802 - 6 , oriented in the second direction, may be positioned at approximately 10 degrees, approximately 130 degrees, and approximately 250 degrees around the perimeter of the aerial vehicle  800  with respect to the X axis. 
     In other implementations, the propulsion mechanisms may have other alignments. Likewise, in other implementations, there may be fewer or additional propulsion mechanisms. Likewise, in some implementations, the propulsion mechanisms may not all be aligned in the same plane and/or the ring wing may be in a different plane than some or all of the propulsion mechanisms. 
     While the examples discussed above and illustrated in  FIGS.  5 - 8    discuss rotating the propulsion mechanisms approximately thirty degrees about each respective motor arm and that the ring wing is offset approximately thirty degrees with respect to the fuselage, in other implementations, the orientation of the propulsion mechanisms and/or the ring wing may be greater or less than thirty degrees and the angle of the ring wing may be different than the angle of one or more propulsion mechanisms. In some implementations, if maneuverability of the aerial vehicle when the aerial vehicle is in VTOL orientation is of higher importance, the orientation of the propulsion mechanisms may be higher than thirty degrees. For example, each of the propulsion mechanisms may be oriented approximately forty-five degrees about each respective motor arm, in either the first or second direction. In comparison, if the lifting force of the aerial vehicle when the aerial vehicle is in the VTOL orientation is of higher importance, the orientation of the propulsion mechanisms may be less than thirty degrees. For example, each propulsion mechanism may be oriented approximately ten degrees from a vertical orientation about each respective motor arm. 
     In some implementations, the orientations of some propulsion mechanisms may be different than other propulsion mechanisms. For example, propulsion mechanisms  802 - 1 ,  802 - 3 , and  802 - 5  may each be oriented approximately fifteen degrees in the first direction and propulsion mechanisms  802 - 2 ,  802 - 4 , and  802 - 6  may be oriented approximately twenty-five degrees in the second direction. In still other examples, pairs of propulsion mechanisms may have different orientations than other pairs of propulsion mechanisms. For example, propulsion mechanisms  802 - 1  and  802 - 6  may each be oriented approximately thirty degrees in the first direction and second direction, respectively, toward one another, propulsion mechanisms  802 - 3  and  802 - 2  may each be oriented approximately forty-five degrees in the first direction and second direction, respectively, toward one another, and propulsion mechanisms  802 - 5  and  802 - 4  may each be oriented approximately forty-five degrees in the first direction and second direction, respectively, toward one another. 
     As discussed below, by orienting propulsion mechanisms partially toward one another in pairs, as illustrated, the lateral or horizontal forces generated by the pairs of propulsion mechanisms, when producing the same amount of force, will cancel out such that the sum of the forces from the pair is only in a substantially vertical direction (Z direction), when the aerial vehicle is in the VTOL orientation. Likewise, as discussed below, if one propulsion mechanism of the pair produces a force larger than a second propulsion mechanism, a lateral or horizontal force will result in the X direction and/or the Y direction, when the aerial vehicle is in the VTOL orientation. A horizontal force produced from one or more of the pairs of propulsion mechanisms enables the aerial vehicle to translate in a horizontal direction and/or yaw without altering the pitch of the aerial vehicle, when the aerial vehicle is in the VTOL orientation. Producing lateral forces by multiple pairs of propulsion mechanisms  802  enables the aerial vehicle  800  to operate independently in any of the six degrees of freedom (surge, sway, heave, pitch, yaw, and roll). As a result, the stability and maneuverability of the aerial vehicle  800  is increased. 
     While the implementations illustrated in  FIGS.  5 - 8    include six arms that extend radially from a central portion of the aerial vehicle and are coupled to the ring wing, in other implementations, there may be fewer or additional arms. For example, the aerial vehicle may include support arms that extend between the arms  505  and provide additional support to the aerial vehicle. As another example, not all of the motor arms may extend to and couple with the ring wing. 
     While the examples discussed above in  FIGS.  1 - 8    describe a ring wing in either a substantially circular shape ( FIGS.  1 - 4   ) or a substantially hexagonal shape ( FIGS.  5 - 8   ), in other implementations, the ring wing may have other shapes. For example, the ring wing may be substantially square, rectangular, pentagonal, octagonal, etc. 
       FIG.  9    is a flow diagram illustrating an example maneuverability process  900 , according to disclosed implementations. The example maneuverability process  900  is performed when the aerial vehicle is in VTOL orientation. The example process  900  begins by receiving an aerial navigation command that includes a maneuver, as in  902 . A maneuver may be any command to alter or change an aspect of the aerial vehicle&#39;s current flight. For example, a maneuver may be to ascend or descend (heave), increase or decrease speed (surge), move right or left (sway), pitch, yaw, roll, and/or any combination thereof. 
     Based on the commanded maneuver, the example process determines the propulsion mechanisms to be used in executing the maneuver, as in  903 . As discussed herein, the aerial vehicle may include multiple propulsion mechanisms, as discussed herein, that may be selectively used to generate thrusts that will cause the aerial vehicle to execute one or more maneuvers, in any of the six degrees of freedom, when the aerial vehicle is in the VTOL orientation. 
     In addition to determining the propulsion mechanisms that are to be used to execute the maneuvers, the magnitude and direction of the thrust to be generated by each of the propulsion mechanisms is determined, as in  904 . As discussed above, in some implementations, the propulsion mechanisms may be configured to generate forces in either direction in which they are aligned. Alternatively, or in addition thereto, the propulsion mechanisms may be configured such that they are rotatable between two or more positions so that forces generated by the propulsion mechanism may be oriented in different directions. In other implementations, the propulsion mechanisms may be secured at fixed positions on the aerial vehicle. 
     Based on the determined propulsion mechanisms that are to be used to generate the commanded maneuvers and the determined magnitudes and directions of the forces to be generated by those propulsion mechanisms, instructions are sent to the determined propulsion mechanisms that cause the forces to be generated, as in  906 .  FIGS.  14 - 19    illustrate examples of different forces that may be generated by each propulsion mechanism to execute one or more commanded maneuvers in any of the six degrees of freedom. 
       FIG.  10    is a flow diagram illustrating an example transition from vertical flight to horizontal flight process  1000 , in accordance with disclosed implementations. The example process may be performed by any of the aerial vehicles discussed herein that include a plurality of propulsion mechanisms and a ring wing surrounding at least a portion of the plurality of propulsion mechanisms, when the aerial vehicle is operating in a VTOL orientation. The example process  1000  begins upon receipt of an aerial command that includes a horizontal component, as in  1002 . The command may be received from a remote source, such as a controller, remote computing resource, other aerial vehicle, etc. In other examples, the command may be part of a defined flight path, determined by the aerial vehicle as part of autonomous operation, etc. 
     Upon receipt of a command with a horizontal component, forces are generated by respective propulsion mechanisms and/or by one or more ailerons of the ring wing that cause the aerial vehicle to pitch forward and increase in speed in the commanded horizontal direction, as in  1004 . As discussed further below, different forces may be produced by different propulsion mechanisms that cause a pitching moment about the Y axis and a surge in the X direction. 
     As the aerial vehicle is pitching forward and surging in the commanded X direction, a determination is made as to whether a horizontal airspeed and a pitch angle both exceed respective thresholds, as in  1006 . The pitch angle threshold and corresponding horizontal airspeed threshold may be dependent upon one another and correspond to a pitch and horizontal airspeed necessary for the aerial vehicle to receive sufficient lift from the ring wing of the aerial vehicle for horizontal flight. 
     If it is determined that one or both of the horizontal airspeed or the pitch angle do not exceed respective thresholds, a determination is made as to whether the command has been satisfied, as in  1008 . If it is determined that the command has been satisfied, the example process completes, as in  1010 . If it is determined that the command has not been satisfied, the example process  1000  returns to block  1004  and continues. 
     Returning to decision block  1006 , if it is determined that both the horizontal air speed exceeds the horizontal airspeed threshold and the pitch angle exceeds the pitch angle threshold, the thrust of the two propulsion mechanisms that are oriented in a substantially horizontal direction is increased, as in  1012 , and the thrust generated by the other propulsion mechanisms, referred to as the maneuverability propulsion mechanisms when the aerial vehicle is in a horizontal flight orientation, is decreased or terminated, as in  1014 . When the aerial vehicle is moving in a horizontal direction that exceeds the horizontal airspeed threshold, and the pitch angle of the aerial vehicle exceeds the pitch angle threshold, the aerial vehicle is considered to be in the horizontal flight orientation discussed above. 
     When the aerial vehicle is in the horizontal flight orientation, the thrust of the horizontally aligned propulsion mechanisms is increased to continue to propel the aerial vehicle in a horizontal direction and to account for the decrease in thrust provided by the other propulsion mechanisms. When the aerial vehicle is in the horizontal flight orientation and moving at a horizontal airspeed speed that exceeds the airspeed threshold, the aerodynamic shape of the ring wing produces sufficient lift to maintain the aerial vehicle in horizontal flight. The forces generated by the horizontally aligned propulsion mechanisms propel the aerial vehicle horizontally. 
     The aerial vehicle continues to aerially navigate in the horizontal direction and completes the aerial command, as in  1016 . The horizontal flight orientation of the implementations described herein improve the efficiency and flight range of the aerial vehicles compared to aerial vehicles that must utilize all propulsion mechanisms to horizontally navigate. 
       FIG.  11    is a flow diagram illustrating an example transition from horizontal flight to vertical flight process  1100 , in accordance with disclosed implementations. The example process may be performed by any of the aerial vehicles discussed herein that include a plurality of propulsion mechanisms and a ring wing surrounding at least a portion of the plurality of propulsion mechanisms, when the aerial vehicle is operating in a horizontal flight orientation. The example process  1100  begins upon receipt of an aerial command that includes a vertical component, as in  1102 . The command may be received from a remote source, such as a controller, remote computing resource, other aerial vehicle, etc. In other examples, the command may be part of a defined flight path, determined by the aerial vehicle as part of autonomous operation, etc. 
     Upon receiving a command that includes a vertical component, forces are generated by one or more of the propulsion mechanisms and/or one or more ailerons of the ring wing that cause the pitch of the aerial vehicle to decrease and may cause the horizontal airspeed to decrease, as in  1104 . As discussed further below, different forces may be produced by different propulsion mechanisms that cause a pitching moment about the Y axis to decrease. 
     As the pitch of the aerial vehicle decreases and possibly the horizontal airspeed decreases, a determination is made as to whether the horizontal airspeed or the pitch angle of the aerial vehicle are below respective thresholds, as in  1106 . The pitch angle threshold and corresponding horizontal airspeed threshold may be dependent upon one another and correspond to a pitch and horizontal airspeed necessary for the aerial vehicle to receive sufficient lift from the ring wing of the aerial vehicle for horizontal flight. 
     If it is determined that neither the pitch angle nor the horizontal airspeed are below respective thresholds, a determination is made as to whether the command has been satisfied, as in  1108 . If it is determined that the command has been satisfied, the example process completes, as in  1110 . If it is determined that the command has not been satisfied, the example process  1100  returns to block  1104  and continues. 
     Returning to decision block  1106 , if it is determined that either the horizontal air speed is below the horizontal airspeed threshold or the pitch angle is below the pitch angle threshold, the thrust of the two propulsion mechanisms that were oriented in a substantially horizontal direction is decreased, as in  1112 , and the thrust generated by the other propulsion mechanisms is increased, as in  1114 . When the aerial vehicle is moving below a horizontal airspeed threshold and has a pitch angle that is below the pitch angle threshold, the aerial vehicle is considered to be in the VTOL orientation discussed above. 
     When the aerial vehicle is in the VTOL orientation, the thrust produced by each of the propulsion mechanisms is used to maintain flight of the aerial vehicle and to aerially navigate or maneuver the aerial vehicle. 
     The aerial vehicle continues to aerially navigate in the vertical direction and completes the aerial command, as in  1116 . The VTOL flight orientation of the implementations described herein improve the maneuverability of the aerial vehicle, enabling the aerial vehicle to complete vertical takeoff, landing, payload delivery, and to operate and maneuver within confined spaces. 
     Providing an aerial vehicle that can transition between a VTOL orientation and a horizontal flight orientation, as discussed herein, improves the overall performance, safety, and efficiency of the aerial vehicle. For example, if the aerial vehicle is to aerially navigate a customer ordered item for delivery to the customer, the aerial vehicle may be loaded with the payload (customer item), depart in a substantially vertical direction from a source location in a VTOL orientation until the aerial vehicle reaches a defined altitude and then transition to a horizontal flight orientation to efficiently and quickly navigate to a position at a defined altitude above the customer delivery location. Upon reaching a position above the customer delivery location, the aerial vehicle can transition from the horizontal flight orientation to the VTOL orientation, descend vertically to the delivery location and deliver the item. Upon completion of item delivery, the aerial vehicle may ascend vertically and navigate to another location. 
       FIG.  12    illustrates an example flight transition  1201  from a vertical takeoff in a VTOL orientation to horizontal flight in a horizontal flight orientation, in accordance with disclosed implementations. The transition from a VTOL orientation to horizontal flight orientation may be performed by any of the aerial vehicles discussed herein. In this example, at an initial time, the aerial vehicle  1200 - 1  is landed, positioned in a VTOL orientation such that the ring wing  1207 - 1  is horizontally aligned in the X-Y plane and the fuselage  1210 - 1  is rotated at an angle with respect to vertical. The landing gear  1203 - 1  is also deployed to support the aerial vehicle. 
     The aerial vehicle then produces vertical thrust using propulsion mechanisms that cause the aerial vehicle to vertically ascend to an altitude, as illustrated by aerial vehicle  1200 - 2 . At the second point in time, the aerial vehicle  1200 - 2  is still in the VTOL orientation, with the fuselage  1210 - 2  rotated from vertical and the ring wing and corresponding propulsion mechanisms horizontally aligned in the X-Y plane. In this example, as the aerial vehicle ascends the landing gear  1203 - 2  rotates and begins to contract toward the ring wing  1207 - 2 . 
     At time three, illustrated by aerial vehicle  1200 - 3 , the aerial vehicle begins to pitch forward by producing different forces by different propulsion mechanisms that cause a pitch moment about the Y axis. As illustrated, as the aerial vehicle  1200 - 3  begins to pitch forward, the ring wing  1207 - 3  and the propulsion mechanisms are no longer horizontally aligned and the aerial vehicle begins moving in the direction of the alignment of the fuselage  1210 - 3 . Finally, at time three, the landing gear  1203 - 3  in this example has been fully retracted. 
     At time four, as illustrated by aerial vehicle  1200 - 4 , pitch of the aerial vehicle  1200 - 4  continues to increase and the horizontal airspeed of the vehicle continues to increase. As the pitch and horizontal airspeed increase, the ring wing moves into a more vertical orientation and begins to generate a lifting force that will maintain the aerial vehicle at an altitude. In addition, the lifting force generated by the ring wing will cause the aerial vehicle to continue to rotate to the horizontal flight orientation, as illustrated at time five by aerial vehicle  1200 - 5 . 
     At time five, the aerial vehicle  1200 - 5  is in the horizontal flight orientation, the fuselage  1210 - 5  is oriented horizontally and the aerial vehicle is aerially navigating in a direction that includes a substantially horizontal component. As discussed above, when the aerial vehicle is in the horizontal flight orientation, two of the propulsion mechanisms are horizontally aligned to produce thrusting forces in the substantially horizontal direction. As such, the forces produced by those two propulsion mechanisms are increased and the other propulsion mechanisms disabled, reduced, or allowed to rotate freely to produce energy that is used to charge a power module of the aerial vehicle. In some implementations, the non-used propulsion mechanisms may be adjustable such that they can be folded or positioned out of the way to reduce drag of the aerial vehicle. 
     As the aerial vehicle operates in the horizontal flight orientation, as illustrated at time six by aerial vehicle  1200 - 6 , the fuselage  1210 - 6  remains horizontally oriented in the direction of travel and the ring wing  1207 - 6  remains oriented to produce lift that supports efficient horizontal flight of the aerial vehicle. In the horizontal flight orientation, the aerial vehicle can aerially navigate at high speeds with lower power consumption, thereby increasing the operating range of the aerial vehicle. 
       FIG.  13    illustrates an example flight transition  1301  from a horizontal flight orientation to a VTOL orientation, in accordance with disclosed implementations. In this example, at time one, illustrated by aerial vehicle  1300 - 1 , the aerial vehicle is in the horizontal flight orientation and aerially navigating in a substantially horizontal direction. At time two, illustrated by aerial vehicle  1300 - 2 , the aerial vehicle receives a command to transition to a VTOL orientation and descend. In executing the command, the forces generated by the propulsion mechanisms and/or the ailerons of the ring wing, cause the pitch of the aerial vehicle  1300 - 3  to begin to decrease such that the ring wing  1307 - 3  begins to rotate toward horizontal and the fuselage  1310 - 3  begins to rotate away from the horizontal orientation. As the pitch decreases and the ring wing rotates, the horizontal airspeed of the aerial vehicle decreases and the lifting force generated by the ring wing decreases. To counteract the decrease in lift from the ring wing, the forces generated by the propulsion mechanisms of the aerial vehicle are increased so that the aerial vehicle maintains flight. 
     At time four, illustrated by aerial vehicle  1300 - 4 , the horizontal airspeed has substantially terminated, the pitch of the aerial vehicle continues to decrease such that the ring wing  1307 - 4  continues to rotate more toward horizontal and the fuselage  1310 - 4  continues to rotate upward. Likewise, the forces produced by the propulsion mechanisms of the aerial vehicle  1300 - 4  are producing lift sufficient to maintain the aerial vehicle at altitude. 
     At time five, illustrated by aerial vehicle  1300 - 5 , the aerial vehicle has completed transition such that the ring wing  1307 - 5  is horizontally aligned in the X-Y plane, the fuselage  1310 - 5  is rotated away from horizontal and the propulsion mechanisms of the aerial vehicle  1300 - 5  are providing lift and maneuverability of the aerial vehicle  1300 - 5 . 
     By decreasing the forces produced by the propulsion mechanisms, the aerial vehicle  1300 - 6 , at time six, is descending and the landing gear  1303 - 6  begins to deploy. Finally, at time seven, the aerial vehicle  1300 - 7  has descended, the landing gear  1303 - 7  has deployed and the aerial vehicle maintains the VTOL orientation in which the ring wing  1307 - 7  and corresponding propulsion mechanisms are horizontally aligned in the X-Y plane. In this example, the forces generated by the propulsion mechanisms allow the aerial vehicle to hover above the surface. In such a position, the aerial vehicle  1300 - 7  may deploy or complete delivery of a payload, land, ascend, or move in any of the six degrees of freedom. 
       FIGS.  14 - 19    are diagrams of the propulsion mechanisms of the aerial vehicle illustrated in  FIGS.  1 - 8    viewed from overhead, or from a top-down perspective, when the aerial vehicle is in a VTOL orientation. To aid in explanation, other components of the aerial vehicle have been omitted from  FIGS.  14 - 19    and different forces in the X or Y direction that may be generated by one or more of the propulsion mechanisms are illustrated by vectors. For purposes of discussion, forces generated in the Z direction, or the Z component of forces by the propulsion mechanisms have been omitted from  FIGS.  14 - 19   . Except where otherwise noted, the sum of the Z components of the forces produced by the propulsion mechanisms are equal and opposite the gravitation force acting on the aerial vehicle such that the altitude of the aerial vehicle will remain substantially unchanged. 
     As will be appreciated, the altitude or vertical position of the aerial vehicle may be increased or decreased by further altering the forces generated by the propulsion mechanisms such that the sum of the Z components of the forces are greater (to increase altitude) or less (to decrease altitude) than the gravitational force acting upon the aerial vehicle. 
     The illustrated forces, when generated, will cause the aerial vehicle, when the aerial vehicle is in the illustrated VTOL orientation, to surge in the X direction ( FIG.  14   ), sway in the Y direction ( FIG.  15   ), hover ( FIG.  16   ), pitch ( FIG.  17   ), yaw ( FIG.  18   ), and roll ( FIG.  19   ). 
     While the below examples discuss summing of the components of the forces to determine a magnitude and direction of a net force and/or a moment, it will be appreciated that the discussion is for explanation purposes only. The net forces and moments for the illustrated aerial vehicles may be determined by control systems, such as that discussed with respect to  FIG.  20    based on the configuration of the aerial vehicle. For example, an influence matrix may be utilized to determine a net force (or net force components) and moments for an aerial vehicle given particular forces or thrusts generated by each propulsion mechanism. Likewise, an inverse influence matrix may be utilized to determine required forces or thrusts for each propulsion mechanism given a desired force, or net force components and moments. 
     Referring to the aerial vehicle illustrated in  FIGS.  1 - 8    and assuming the propulsion mechanisms are oriented about the respective motor arms approximately thirty degrees in alternating directions, and assuming the propulsion mechanisms are located 1 radius from the origin of the aerial vehicle and the aerial vehicle is in the VTOL orientation, the following influence matrix may be used to determine the X, Y, and Z components of a net force and the moments about the X, Y, and Z axis given thrusts for each of the six propulsion mechanisms: 
     
       
         
           
             
               
                 
                   
                     [ 
                     .250 
                   
                 
                 
                   
                     - 
                     .433 
                   
                 
                 
                   .866 
                 
                 
                   .425 
                 
                 
                   
                     - 
                     .736 
                   
                 
                 
                   
                     
                       - 
                       .528 
                     
                     ] 
                   
                 
                 
                   
                     [ 
                     
                       T 
                       ⁢ 
                       
                           
                       
                       ⁢ 
                       1 
                     
                     ] 
                   
                 
               
               
                 
                   
                     [ 
                     
                       - 
                       .500 
                     
                   
                 
                 
                   0 
                 
                 
                   .866 
                 
                 
                   .850 
                 
                 
                   0 
                 
                 
                   
                     .528 
                     ] 
                   
                 
                 
                   
                     [ 
                     
                       T 
                       ⁢ 
                       
                           
                       
                       ⁢ 
                       2 
                     
                     ] 
                   
                 
               
               
                 
                   
                     [ 
                     .250 
                   
                 
                 
                   .433 
                 
                 
                   .866 
                 
                 
                   .425 
                 
                 
                   .736 
                 
                 
                   
                     
                       - 
                       .528 
                     
                     ] 
                   
                 
                 
                   
                     [ 
                     
                       T 
                       ⁢ 
                       
                           
                       
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                       3 
                     
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                     [ 
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                   .866 
                 
                 
                   
                     - 
                     .425 
                   
                 
                 
                   .736 
                 
                 
                   
                     .528 
                     ] 
                   
                 
                 
                   
                     [ 
                     
                       T 
                       ⁢ 
                       
                           
                       
                       ⁢ 
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                     [ 
                     
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                       ⁢ 
                       
                           
                       
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                     .528 
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     Likewise, the following inverse influence matrix may be used to determine the thrusts for each of the six propulsion mechanisms given desired net force components and moments: 
     
       
         
           
             
               
                 
                   
                     
                       [ 
                       .333 
                     
                   
                   
                     
                       - 
                       .577 
                     
                   
                   
                     .192 
                   
                   
                     .196 
                   
                   
                     
                       - 
                       .340 
                     
                   
                   
                     
                       
                         - 
                         .316 
                       
                       ] 
                     
                   
                 
                 
                   
                     
                       [ 
                       
                         - 
                         .667 
                       
                     
                   
                   
                     0 
                   
                   
                     .192 
                   
                   
                     .392 
                   
                   
                     0 
                   
                   
                     
                       .316 
                       ] 
                     
                   
                 
                 
                   
                     
                       [ 
                       .333 
                     
                   
                   
                     .577 
                   
                   
                     .192 
                   
                   
                     .196 
                   
                   
                     .340 
                   
                   
                     
                       
                         - 
                         .316 
                       
                       ] 
                     
                   
                 
                 
                   
                     
                       [ 
                       .333 
                     
                   
                   
                     
                       - 
                       .577 
                     
                   
                   
                     .192 
                   
                   
                     
                       - 
                       .196 
                     
                   
                   
                     .340 
                   
                   
                     
                       .316 
                       ] 
                     
                   
                 
                 
                   
                     
                       [ 
                       
                         - 
                         .667 
                       
                     
                   
                   
                     0 
                   
                   
                     .192 
                   
                   
                     
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                       .392 
                     
                   
                   
                     0 
                   
                   
                     
                       
                         - 
                         .316 
                       
                       ] 
                     
                   
                 
                 
                   
                     
                       [ 
                       .333 
                     
                   
                   
                     .577 
                   
                   
                     .192 
                   
                   
                     
                       - 
                       .196 
                     
                   
                   
                     
                       - 
                       .340 
                     
                   
                   
                     
                       .316 
                       ] 
                     
                   
                 
               
               ⁢ 
               
                 
                   
                     
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                       Fx 
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                       Fy 
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                       ] 
                     
                   
                 
                 
                   
                     
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                       Mz 
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             = 
             
               
                 
                   
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                       T 
                       ⁢ 
                       
                           
                       
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                       1 
                     
                     ] 
                   
                 
               
               
                 
                   
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                       ⁢ 
                       
                           
                       
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                       2 
                     
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                       3 
                     
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                       4 
                     
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                       5 
                     
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                       6 
                     
                     ] 
                   
                 
               
             
           
         
       
     
       FIG.  14    is a diagram of the propulsion mechanisms  1402  of the aerial vehicles discussed herein with thrust vectors  1403  to cause the aerial vehicle to surge in the X direction, when the aerial vehicle is in the VTOL orientation, in accordance with disclosed implementations. As discussed above, each of the propulsion mechanisms  1402  are approximately in the same plane, in this example, the X-Y plane and oriented in pairs  1406  as discussed above. Likewise, while the aerial vehicle may navigate in any direction, when the aerial vehicle is in the VTOL orientation,  FIG.  14    indicates a heading of the aerial vehicle  1400 . 
     In the configuration of the aerial vehicle  1400 , to cause the aerial vehicle  1400  to surge in the X direction, propulsion mechanisms  1402 - 1 ,  1402 - 3 ,  1402 - 4 , and  1402 - 6  generate forces  1403 - 1 ,  1403 - 3 ,  1403 - 4 , and  1403 - 6  of approximately equal magnitude, referred to in this example as a first magnitude. Likewise, propulsion mechanisms  1402 - 2  and  1402 - 5  each produce a force  1403 - 2  and  1403 - 5  of equal magnitude, referred to herein as a second magnitude. The second magnitude of forces  1403 - 2  and  1403 - 5  is less than the first magnitude of the forces  1403 - 1 ,  1403 - 3 ,  1403 - 4 , and  1403 - 6 . Each of the forces  1403 - 1 ,  1403 - 2 ,  1403 - 3 ,  1403 - 4 ,  1403 - 5 , and  1403 - 6  have an X component, a Y component, and a Z component. As discussed above, the sum of the Z components of the forces  1403 - 1 ,  1403 - 2 ,  1403 - 3 ,  1403 - 4 ,  1403 - 5 , and  1403 - 6  in the illustrated example is equal and opposite to the gravitational force acting upon the aerial vehicle. Accordingly, for ease of explanation and illustration, the Z components of the forces have been omitted from discussion and  FIG.  14   . 
     Because of the orientation of the first propulsion mechanism  1402 - 1  in the first direction and because the first propulsion mechanism  1402 - 1  is producing a first force  1403 - 1  having the first magnitude, the first force  1403 - 1  has a direction that includes a positive X component  1403 - 1   x  and a negative Y component  1403 - 1   y . Likewise, because of the orientation of the sixth propulsion mechanism  1402 - 6  in the second direction and because the sixth propulsion mechanism  1402 - 6  is producing a sixth force  1403 - 6  having the first magnitude, the sixth force  1403 - 6  has a direction that includes a positive X component  1403 - 6   x  and a positive Y component  1403 - 6   y . In addition, because both forces  1403 - 1  and  1403 - 6  are of approximately equal magnitude and the orientation of the propulsion mechanisms are both approximately thirty degrees but in opposing directions, the magnitude of the respective X components are approximately equal, the direction of the X components are the same, the magnitude of the respective Y components are approximately equal, and the direction of the Y components are opposite. Summing the forces  1403 - 1  and  1403 - 6 , the resultant force  1407 - 1  for the first pair  1406 - 1  of propulsion mechanisms has a third magnitude, a positive X component that is the sum of the X component  1403 - 1   x  and the X component  1403 - 6   x , and no Y component, because the sum of the positive Y component  1403 - 6   y  and the negative Y component  1403 - 1   y  cancel each other out. 
     Turning to the second pair  1406 - 2  of propulsion mechanisms  1402 - 2  and  1402 - 3 , because of the orientation of the third propulsion mechanism  1402 - 3  in the first direction and because the third propulsion mechanism  1402 - 3  is producing a third force  1403 - 3  having the first magnitude, the third force  1403 - 3  has a direction that includes a positive X component  1403 - 3   x  and a positive Y component  1403 - 3   y . Likewise, because of the orientation of the second propulsion mechanism  1402 - 2  in the second direction and because the second propulsion mechanism  1402 - 2  is producing a second force  1403 - 2  having the second magnitude, the second force  1403 - 2  has a direction that includes a negative X component  1403 - 2   x  and a positive Y component  1403 - 2   y . Summing the forces  1403 - 3  and  1403 - 2 , the resultant force  1407 - 2  for the second pair  1406 - 2  of propulsion mechanisms has a fourth magnitude, a positive X component  1407 - 2   x  that is the difference of the larger positive X component  1403 - 3   x  and the smaller negative X component  1403 - 2   x , and a positive Y component  1407 - 2   y  that is the sum of the positive Y component  1403 - 3   y  and the positive Y component  1403 - 2   y.    
     For the third pair  1406 - 3  of propulsion mechanisms  1402 - 5  and  1402 - 4 , because of the orientation of the fifth propulsion mechanism  1402 - 5  in the first direction and because the fifth propulsion mechanism  1402 - 5  is producing a fifth force  1403 - 5  having the second magnitude, the fifth force  1403 - 5  has a direction that includes a negative X component  1403 - 5   x  and a negative Y component  1403 - 5   y . Likewise, because of the orientation of the fourth propulsion mechanism  1402 - 4  in the second direction and because the fourth propulsion mechanism  1402 - 4  is producing a fourth force  1403 - 4  having the first magnitude, the fourth force  1403 - 4  has a direction that includes a positive X component  1403 - 4   x  and a negative Y component  1403 - 4   y . Summing the forces  1403 - 5  and  1403 - 4 , the resultant force  1407 - 3  for the third pair  1406 - 3  of propulsion mechanisms has the fourth magnitude, a positive X component  1407 - 3   x  that is the difference of the larger positive X component  1403 - 4   x  and the smaller negative X component  1403 - 5   x , and a negative Y component  1407 - 3   y  that is the sum of the negative Y component  1403 - 5   y  and the negative Y component  1403 - 4   y.    
     Because of the positioning of the second pair  1406 - 2  with respect to the third pair  1406 - 3  of propulsion mechanisms and because the pairs are producing similar forces, the resultant forces  1407 - 2  and  1407 - 3  have approximately the same magnitude, the fourth magnitude, approximately the same X component magnitudes having the same directions, and approximately equal Y component magnitudes, but having opposite directions. 
     Finally, summing each of the three resultant forces  1407 - 1 ,  1407 - 2 , and  1407 - 3 , the net force  1409  has a fifth magnitude, a positive X direction having a magnitude that is the sum of the x components  1407 - 1   x ,  1407 - 2   x , and  1407 - 3   x  of the first resultant force  1407 - 1 , the second resultant force  1407 - 2 , and the third resultant force  1407 - 3  and no Y component, because first resultant force  1407 - 1  has no Y component and the magnitudes of opposing Y components  1407 - 2   y  and  1407 - 3   y  of the second resultant force  1407 - 2  and third resultant force  1407 - 3  cancel each other out. Because the net force  1409  has a fifth magnitude, a positive X component and no Y component, the net force  1409  will cause the aerial vehicle  1400  to surge in the positive X direction. 
       FIG.  15    is a diagram of the propulsion mechanisms  1502  of the aerial vehicles discussed herein with thrust vectors  1503  to cause the aerial vehicle to sway in the Y direction, when the aerial vehicle is in the VTOL orientation, in accordance with disclosed implementations. As discussed above, each of the propulsion mechanisms  1502  are approximately in the same plane, in this example, the X-Y plane and oriented in pairs  1506  as discussed above. Likewise, while the aerial vehicle may navigate in any direction, when the aerial vehicle is in the VTOL orientation,  FIG.  15    indicates a heading of the aerial vehicle  1500 . 
     In the configuration of the aerial vehicle  1500 , to cause the aerial vehicle  1500  to sway in the Y direction, the first propulsion mechanism  1502 - 1  generates a first force  1503 - 1  of a first magnitude, the second propulsion mechanism  1502 - 2  generates a second force  1503 - 2  of a second magnitude, the third propulsion mechanism  1502 - 3  generates a third force of a third magnitude, the fourth propulsion mechanism  1502 - 4  generates a fourth force  1503 - 4  of a fourth magnitude, the fifth propulsion mechanism  1502 - 5  generates a fifth force  1503 - 5  of a fifth magnitude, and the sixth propulsion mechanism  1502 - 6  generates a sixth force  1503 - 6  of a sixth magnitude. 
     Each of the forces  1503 - 1 ,  1503 - 2 ,  1503 - 3 ,  1503 - 4 ,  1503 - 5 , and  1503 - 6  have an X component, a Y component, and a Z component. As discussed above, the sum of the Z components of the forces  1503 - 1 ,  1503 - 2 ,  1503 - 3 ,  1503 - 4 ,  1503 - 5 , and  1503 - 6  in the illustrated example is equal and opposite to the gravitational force acting upon the aerial vehicle. Accordingly, for ease of explanation and illustration, the Z components of the forces have been omitted from discussion and  FIG.  15   . 
     Because of the orientation of the first propulsion mechanism  1502 - 1  in the first direction and because the first propulsion mechanism  1502 - 1  is producing a first force  1503 - 1  having the first magnitude, the first force  1503 - 1  has a direction that includes a positive X component  1503 - 1   x  and a negative Y component  1503 - 1   y . Likewise, because of the orientation of the sixth propulsion mechanism  1502 - 6  in the second direction and because the sixth propulsion mechanism  1502 - 6  is producing a sixth force  1503 - 6  having a sixth magnitude, the sixth force  1503 - 6  has a direction that includes a positive X component  1503 - 6   x  and a positive Y component  1503 - 6   y . Summing the forces  1503 - 1  and  1503 - 6 , the resultant force  1507 - 1  for the first pair  1506 - 1  of propulsion mechanisms has a seventh magnitude, a positive X component  1507 - 1   x  that is the sum of the X component  1503 - 1   x  and the X component  1503 - 6   x , and positive Y component  1507 - 1   y  that is the difference between the larger positive Y component  1503 - 6   y  and the smaller negative Y component  1503 - 1   y.    
     Turning to the second pair  1506 - 2  of propulsion mechanisms  1502 - 2  and  1502 - 3 , because of the orientation of the third propulsion mechanism  1502 - 3  in the first direction and because the third propulsion mechanism  1502 - 3  is producing the third force  1503 - 3  having the third magnitude, the third force  1503 - 3  has a direction that includes a positive X component  1503 - 3   x  and a positive Y component  1503 - 3   y . Likewise, because of the orientation of the second propulsion mechanism  1502 - 2  in the second direction and because the second propulsion mechanism  1502 - 2  is producing a second force  1503 - 2  having the second magnitude, the second force  1503 - 2  has a direction that includes a negative X component  1503 - 2   x  and a positive Y component  1503 - 2   y . Summing the forces  1503 - 3  and  1503 - 2 , the resultant force  1507 - 2  for the second pair  1506 - 2  of propulsion mechanisms has an eighth magnitude, a negative X component  1507 - 2   x  that is the difference of the larger negative X component  1503 - 2   x  and the smaller positive X component  1503 - 3   x , and a positive Y component  1507 - 2   y  that is the sum of the positive Y component  1503 - 3   y  and the positive Y component  1503 - 2   y.    
     For the third pair  1506 - 3  of propulsion mechanisms  1502 - 5  and  1502 - 4 , because of the orientation of the fifth propulsion mechanism  1502 - 5  in the first direction and because the fifth propulsion mechanism  1502 - 5  is producing the fifth force  1503 - 5  having the fifth magnitude, the fifth force  1503 - 5  has a direction that includes a negative X component  1503 - 5   x  and a negative Y component  1503 - 5   y . Likewise, because of the orientation of the fourth propulsion mechanism  1502 - 4  in the second direction and because the fourth propulsion mechanism  1502 - 4  is producing the fourth force  1503 - 4  having the fourth magnitude, the fourth force  1503 - 4  has a direction that includes a positive X component  1503 - 4   x  and a negative Y component  1503 - 4   y . Summing the forces  1503 - 5  and  1503 - 4 , the resultant force  1507 - 3  for the third pair  1506 - 3  of propulsion mechanisms has a ninth magnitude, a negative X component  1507 - 3   x  that is the difference of the larger negative X component  1503 - 5   x  and the smaller positive X component  1503 - 4   x , and a negative Y component  1507 - 3   y  that is the sum of the negative Y component  1503 - 5   y  and the negative Y component  1503 - 4   y.    
     Because of the positioning of the three pairs of maneuverability components  1506 - 1 ,  1506 - 2 , and  1506 - 3 , the sum of the resultant forces  1507 - 1 ,  1507 - 2 , and  1507 - 3  results in a net force  1509  having a tenth magnitude, a positive Y component and no X component. For example, summing the resultant X components  1507 - 1   x ,  1507 - 2   x , and  1507 - 3   x , the two negative X components  1507 - 2   x  and  1507 - 3   x  combine to cancel out the positive X component  1507 - 1   x , resulting in no X component for the net force  1509 . Similarly, the sum of the two positive Y components  1507 - 1   y  and  1507 - 2   y  are larger than the negative Y component  1507 - 3   y  such that the sum of all the resultant Y components provides a positive Y component for the net force  1509  such that the aerial vehicle  1500  will sway in the positive Y direction. 
       FIG.  16    is a diagram of the propulsion mechanisms  1602  of the aerial vehicles discussed herein with thrust vectors  1603  to cause the aerial vehicle to hover, ascend or descend in the Z direction, when the aerial vehicle is in the VTOL orientation, in accordance with disclosed implementations. As discussed above, each of the propulsion mechanisms  1602  are approximately in the same plane, in this example, the X-Y plane and oriented in pairs  1606  as discussed above. Likewise, while the aerial vehicle may navigate in any direction, when the aerial vehicle is in the VTOL orientation,  FIG.  16    indicates a heading of the aerial vehicle  1600 . 
     In the configuration of the aerial vehicle  1600 , to cause the aerial vehicle  1600  to hover, ascend or descend in the Z direction, the first propulsion mechanism  1602 - 1 , the second propulsion mechanism  1602 - 2 , the third propulsion mechanism  1602 - 3 , the fourth propulsion mechanism  1602 - 4 , the fifth propulsion mechanism  1602 - 5 , and the sixth propulsion mechanism  1602 - 6  all generate a force  1603  of approximately equal magnitude, referred to in this example as a first magnitude. 
     Each of the forces  1603 - 1 ,  1603 - 2 ,  1603 - 3 ,  1603 - 4 ,  1603 - 5 , and  1603 - 6  have an X component, a Y component, and a Z component. As discussed above, in implementations in which the aerial vehicle is to maintain a hover, the sum of the Z components of the forces  1603 - 1 ,  1603 - 2 ,  1603 - 3 ,  1603 - 4 ,  1603 - 5 , and  1603 - 6  in the illustrated example is equal and opposite to the gravitational force acting upon the aerial vehicle. If the aerial vehicle is to ascend, the force generated by each of the propulsion mechanisms is increased in equal amounts such that the sum of the forces in the Z direction is larger than the gravitational force. In comparison, if the aerial vehicle is to descend, the forces generated by each of the propulsion mechanisms is decreased by equal amounts such that the sum of the forces in the Z direction is less than the gravitational force. For ease of explanation and illustration, the Z components of the forces have been omitted from discussion and  FIG.  16   . Discussion with respect to  FIG.  16    will illustrate how the sum X components and Y components cancel out such that the net force  1609  only has a Z component. 
     Because of the orientation of the first propulsion mechanism  1602 - 1  in the first direction and because the first propulsion mechanism  1602 - 1  is producing a first force  1603 - 1  having the first magnitude, the first force  1603 - 1  has a direction that includes a positive X component  1603 - 1   x  and a negative Y component  1603 - 1   y . Likewise, because of the orientation of the sixth propulsion mechanism  1602 - 6  in the second direction and because the sixth propulsion mechanism  1602 - 6  is producing a sixth force  1603 - 6  having the first magnitude, the sixth force  1603 - 6  has a direction that includes a positive X component  1603 - 6   x  and a positive Y component  1603 - 6   y . In addition, because the sixth force  1603 - 6  and the first force  1603 - 1  have the same first magnitude and are oriented in opposing directions, the magnitude of the respective X components and Y components are the same. Likewise, the direction of the respective X components are the same and the direction of the respective Y components are opposite. Summing the forces  1603 - 1  and  1603 - 6 , the resultant force  1607 - 1  for the first pair  1606 - 1  of propulsion mechanisms has a second magnitude, a positive X component that is the sum of the X component  1603 - 1   x  and the X component  1603 - 6   x , and no Y component, because the opposing Y components  1603 - 1   y  and  1603 - 6   y  cancel each other out. 
     Turning to the second pair  1606 - 2  of propulsion mechanisms  1602 - 2  and  1602 - 3 , because of the orientation of the third propulsion mechanism  1602 - 3  in the first direction and because the third propulsion mechanism  1602 - 3  is producing the third force  1603 - 3  having the first magnitude, the third force  1603 - 3  has a direction that includes a positive X component  1603 - 3   x  and a positive Y component  1603 - 3   y . Likewise, because of the orientation of the second propulsion mechanism  1602 - 2  in the second direction and because the second propulsion mechanism  1602 - 2  is producing a second force  1603 - 2  having the first magnitude, the second force  1603 - 2  has a direction that includes a negative X component  1603 - 2   x  and a positive Y component  1603 - 2   y . Summing the forces  1603 - 3  and  1603 - 2 , the resultant force  1607 - 2  for the second pair  1606 - 2  of propulsion mechanisms has a third magnitude, a negative X component  1607 - 2   x  that is the difference of the larger negative X component  1603 - 2   x  and the smaller positive X component  1603 - 3   x , and a positive Y component  1607 - 2   y  that is the sum of the positive Y component  1603 - 3   y  and the positive Y component  1603 - 2   y.    
     For the third pair  1606 - 3  of propulsion mechanisms  1602 - 5  and  1602 - 4 , because of the orientation of the fifth propulsion mechanism  1602 - 5  in the first direction and because the fifth propulsion mechanism  1602 - 5  is producing the fifth force  1603 - 5  having the first magnitude, the fifth force  1603 - 5  has a direction that includes a negative X component  1603 - 5   x  and a negative Y component  1603 - 5   y . Likewise, because of the orientation of the fourth propulsion mechanism  1602 - 4  in the second direction and because the fourth propulsion mechanism  1602 - 4  is producing the fourth force  1603 - 4  having the first magnitude, the fourth force  1603 - 4  has a direction that includes a positive X component  1603 - 4   x  and a negative Y component  1603 - 4   y . Summing the forces  1603 - 5  and  1603 - 4 , the resultant force  1607 - 3  for the third pair  1606 - 3  of propulsion mechanisms has the third magnitude, a negative X component  1607 - 3   x  that is the difference of the larger negative X component  1603 - 5   x  and the smaller positive X component  1603 - 4   x , and a negative Y component  1607 - 3   y  that is the sum of the negative Y component  1603 - 5   y  and the negative Y component  1603 - 4   y.    
     Because of the positioning of the three pairs of maneuverability components  1606 - 1 ,  1606 - 2 , and  1606 - 3 , the sum of the resultant forces  1607 - 1 ,  1607 - 2 , and  1607 - 3  result in a net force  1609  having no X component and no Y component. Specifically, the positive Y component  1607 - 2   y  cancels out with the negative Y component  1607 - 3   y  because they have the same magnitude and opposite directions. Likewise, each of the negative X components  1607 - 2   x  and  1607 - 3   x  are approximately one-half of the positive X component  1607 - 1   x  and combined the three X components cancel out. If the sum of the positive components of the forces  1603  generated from the propulsion mechanisms  1602  is equal and opposite the force of gravity, the aerial vehicle  1600  will hover. In comparison, if the sum of the positive Z components of the forces  1603  is greater than the force of gravity, the aerial vehicle  1600  will heave in the positive Z direction (i.e., in a substantially positive vertical direction). In comparison, if the sum of the Z components of the forces  1603  is less than the force of gravity, the aerial vehicle  1600  will heave in the negative Z direction (i.e., in a substantially negative vertical direction). 
       FIG.  17    is a diagram of the propulsion mechanisms  1702  of the aerial vehicles discussed herein with thrust vectors  1703  to cause the aerial vehicle to pitch about the Y axis, when the aerial vehicle is in the VTOL orientation, in accordance with disclosed implementations. As discussed above, each of the propulsion mechanisms  1702  are approximately in the same plane, in this example, the X-Y plane and oriented in pairs  1706  as discussed above. Likewise, while the aerial vehicle may navigate in any direction, when the aerial vehicle is in the VTOL orientation,  FIG.  17    indicates a heading of the aerial vehicle  1700 . 
     In the configuration of the aerial vehicle  1700 , to cause the aerial vehicle  1700  to pitch about the Y axis, the first propulsion mechanism  1702 - 1  and the sixth propulsion mechanism  1702 - 6  generate a first force  1703 - 1  and sixth force  1703 - 6  that have approximately a same first magnitude. The third propulsion mechanism  1702 - 3  and the fourth propulsion mechanism  1704 - 2  generate a third force  1703 - 3  and a fourth force  1703 - 4  that have approximately a same second magnitude that is greater than the first magnitude. The second propulsion mechanism  1702 - 2  and the fifth propulsion mechanism  1702 - 5  produce a second force  1703 - 2  and a fifth force  1703 - 5  that have approximately a same third magnitude that is greater than the first magnitude and less than the second magnitude. 
     Each of the forces  1703 - 1 ,  1703 - 2 ,  1703 - 3 ,  1703 - 4 ,  1703 - 5 , and  1703 - 6  have an X component, a Y component, and a Z component. In this example, to cause the aerial vehicle  1700  to pitch forward about the Y axis without also surging in the X direction, swaying in the Y direction, or heaving in the Z direction, the sum of the X components of all the forces generated by the propulsion mechanisms cancel out, the sum of the Y components of all the forces generated by the propulsion mechanisms cancel out, and the sum of the Z components of all the forces generated by the propulsion mechanisms and the force of gravity cancel out. However, as discussed further below, because the forces are produced at distances from the origin  1711 , or center of gravity of the aerial vehicle  1700 , and the magnitude of the Z component of the resultant force  1707 - 2  from the second pair of propulsion mechanisms  1706 - 2  and magnitude of the Z component of the resultant force  1707 - 3  from the third propulsion mechanism  1706 - 3  are larger than the magnitude of the Z component of the resultant force  1707 - 1  from the first pair of propulsion mechanisms  1706 - 1 , the difference in the magnitude of the Z components of the forces and the offset from the origin  1711  produce a moment about the Y axis that causes the aerial vehicle to pitch forward about the Y axis. The greater the difference between the magnitude of the combination of Z components of the second pair of propulsion mechanisms  1706 - 2  and the third pair of propulsion mechanisms  1706 - 3  compared to the Z component of the first pair of propulsion mechanisms  1706 - 1 , the greater the moment about the Y axis and the more the aerial vehicle will pitch about the Y axis. For ease of explanation and illustration, the Z components of the individual forces have been omitted from discussion and  FIG.  17   . 
     Because of the orientation of the first propulsion mechanism  1702 - 1  in the first direction and because the first propulsion mechanism  1702 - 1  is producing a first force  1703 - 1  having the first magnitude, the first force  1703 - 1  has a direction that includes a positive X component  1703 - 1   x  and a negative Y component  1703 - 1   y . Likewise, because of the orientation of the sixth propulsion mechanism  1702 - 6  in the second direction and because the sixth propulsion mechanism  1702 - 6  is producing a sixth force  1703 - 6  having the first magnitude, the sixth force  1703 - 6  has a direction that includes a positive X component  1703 - 6   x  and a positive Y component  1703 - 6   y . In addition, because the sixth force  1703 - 6  and the first force  1703 - 1  have the same first magnitude and are oriented in opposing directions, the magnitude of the respective X components and Y components are the same. Likewise, the direction of the respective X components are the same and the direction of the respective Y components are opposite. Summing the forces  1703 - 1  and  1703 - 6 , the resultant force  1707 - 1  for the first pair  1706 - 1  of propulsion mechanisms has a fourth magnitude, a positive X component  1707 - 1   x  that is the sum of the X component  1703 - 1   x  and the X component  1703 - 6   x , and no Y component, because the opposing Y components  1703 - 1   y  and  1703 - 6   y  cancel each other out. In addition, the resultant force  1707 - 1  of the first pair  1706 - 1  has a Z component  1707 - 1   z  having a fifth magnitude in a positive Z component that is the sum of the positive Z components of the forces  1703 - 1  and  1703 - 6 . 
     Turning to the second pair  1706 - 2  of propulsion mechanisms  1702 - 2  and  1702 - 3 , because of the orientation of the third propulsion mechanism  1702 - 3  in the first direction and because the third propulsion mechanism  1702 - 3  is producing the third force  1703 - 3  having the second magnitude, the third force  1703 - 3  has a direction that includes a positive X component  1703 - 3   x  and a positive Y component  1703 - 3   y . Likewise, because of the orientation of the second propulsion mechanism  1702 - 2  in the second direction and because the second propulsion mechanism  1702 - 2  is producing a second force  1703 - 2  having the third magnitude, the second force  1703 - 2  has a direction that includes a negative X component  1703 - 2   x  and a positive Y component  1703 - 2   y . Summing the forces  1703 - 3  and  1703 - 2 , the resultant force  1707 - 2  for the second pair  1706 - 2  of propulsion mechanisms has a sixth magnitude, a negative X component  1707 - 2   x  that is the difference of the larger negative X component  1703 - 2   x  and the smaller positive X component  1703 - 3   x , and a positive Y component  1707 - 2   y  that is the sum of the positive Y component  1703 - 3   y  and the positive Y component  1703 - 2   y . In addition, the resultant force  1707 - 2  of the second pair  1706 - 2  has a Z component having a seventh magnitude in a positive Z component that is larger than the fifth magnitude of the Z component  1707 - 1   z  of the first resultant force  1707 - 1 . 
     For the third pair  1706 - 3  of propulsion mechanisms  1702 - 5  and  1702 - 4 , because of the orientation of the fifth propulsion mechanism  1702 - 5  in the first direction and because the fifth propulsion mechanism  1702 - 5  is producing the fifth force  1703 - 5  having the third magnitude, the fifth force  1703 - 5  has a direction that includes a negative X component  1703 - 5   x  and a negative Y component  1703 - 5   y . Likewise, because of the orientation of the fourth propulsion mechanism  1702 - 4  in the second direction and because the fourth propulsion mechanism  1702 - 4  is producing the fourth force  1703 - 4  having the second magnitude, the fourth force  1703 - 4  has a direction that includes a positive X component  1703 - 4   x  and a negative Y component  1703 - 4   y . Summing the forces  1703 - 5  and  1703 - 4 , the resultant force  1707 - 3  for the third pair  1706 - 3  of propulsion mechanisms has the sixth magnitude, a negative X component  1707 - 3   x  that is the difference of the larger negative X component  1703 - 5   x  and the smaller positive X component  1703 - 4   x , and a negative Y component  1707 - 3   y  that is the sum of the negative Y component  1703 - 5   y  and the negative Y component  1703 - 4   y . In addition, the resultant force  1707 - 3  of the third pair  1706 - 3  has a Z component  1707 - 3  having the seventh magnitude in a positive Z component that is larger than the fifth magnitude of the Z component  1707 - 1   z  of the first resultant force  1707 - 1 . 
     Because of the positioning of the three pairs of maneuverability components  1706 - 1 ,  1706 - 2 , and  1706 - 3 , the sum of the resultant forces  1707 - 1 ,  1707 - 2 , and  1707 - 3  results in a net force having no X component and no Y component. Specifically, the positive Y component  1707 - 2   y  cancels out with the negative Y component  1707 - 3   y  because they have the same magnitude and opposite directions. Likewise, each of the negative X components  1707 - 2   x  and  1707 - 3   x  are approximately one-half of the positive X component  1707 - 1   x  and combined the three X components cancel out. Likewise, the sum of the magnitude of the Z components of the resultant forces  1707 - 1 ,  1707 - 2 , and  1707 - 3  is equal and opposite to the force of gravity acting on the aerial vehicle  1500 . However, because the seventh magnitude of Z components  1707 - 2   z  and  1707 - 3   z  of the resultant forces  1707 - 2  and  1707 - 3  from the second pair of propulsion mechanisms  1706 - 2  and the third pair of propulsion mechanisms  1706 - 3  are each greater than fifth magnitude of the Z component  1707 - 1   z  of the resultant force  1707 - 1  of the first pair of propulsion mechanisms  1706 - 1  and those forces are separated a distance from the origin  1711 , a moment  1709 -P about the Y axis results that causes the aerial vehicle  1500  to pitch forward about the Y axis. 
       FIG.  18    is a diagram of the propulsion mechanisms  1802  of the aerial vehicles discussed herein with thrust vectors  1803  to cause the aerial vehicle to yaw about the Z axis, when the aerial vehicle is in the VTOL orientation, in accordance with disclosed implementations. As discussed above, each of the propulsion mechanisms  1802  are approximately in the same plane, in this example, the X-Y plane and oriented in pairs  1806  as discussed above. Likewise, while the aerial vehicle may navigate in any direction, when the aerial vehicle is in the VTOL orientation,  FIG.  18    indicates a heading of the aerial vehicle  1800 . 
     In the configuration of the aerial vehicle  1800 , to cause the aerial vehicle  1800  to yaw about the Z axis, the first propulsion mechanism  1802 - 1 , the third propulsion mechanism  1802 - 3 , and the fifth propulsion mechanism  1802 - 5  generate a first force  1803 - 1 , a third force  1803 - 3 , and fifth force  1803 - 5  that each have approximately a same first magnitude. Likewise, the second propulsion mechanism  1802 - 2 , the fourth propulsion mechanism  1804 - 4 , and the sixth propulsion mechanism  1802 - 6  generate a second force  1803 - 2 , a fourth force  1803 - 4 , and a sixth force  1803 - 6  that each have approximately a same second magnitude that is larger than the first magnitude. 
     Each of the forces  1803 - 1 ,  1803 - 2 ,  1803 - 3 ,  1803 - 4 ,  1803 - 5 , and  1803 - 6  have an X component, a Y component, and a Z component. In this example, to cause the aerial vehicle  1800  to yaw about the Z axis without also surging in the X direction, swaying in the Y direction, or heaving in the Z direction, the sum of the X components of all the forces generated by the propulsion mechanisms cancel out, the sum of the Y components of all the forces generated by the propulsion mechanisms cancel out, and the sum of the Z components of all the forces generated by the propulsion mechanisms and the force of gravity cancel out. However, as discussed further below, because the forces are produced at distances from the origin  1811 , or a center of gravity of the aerial vehicle  1800 , the resultant forces  1807 - 1 ,  1807 - 2 , and  1807 - 3  of the pairs of propulsion mechanisms  1806 - 1 ,  1806 - 2 , and  1806 - 3  cause a moment about the Z axis in a counter-clockwise direction that cause the aerial vehicle to yaw about the Z axis in the counter-clockwise direction. 
     Because of the orientation of the first propulsion mechanism  1802 - 1  in the first direction and because the first propulsion mechanism  1802 - 1  is producing a first force  1803 - 1  having the first magnitude, the first force  1803 - 1  has a direction that includes a positive X component  1803 - 1   x  and a negative Y component  1803 - 1   y . Likewise, because of the orientation of the sixth propulsion mechanism  1802 - 6  in the second direction and because the sixth propulsion mechanism  1802 - 6  is producing a sixth force  1803 - 6  having the second magnitude, the sixth force  1803 - 6  has a direction that includes a positive X component  1803 - 6   x  and a positive Y component  1803 - 6   y . Summing the forces  1803 - 1  and  1803 - 6 , the resultant force  1807 - 1  for the first pair  1806 - 1  of propulsion mechanisms has a third magnitude, a positive X component  807 - 1   x  that is the sum of the positive X component  1803 - 1   x  and the positive X component  1803 - 6   x , and a positive Y component  1807 - 1   y  that is the difference between the larger positive Y component  1803 - 6   y  and the smaller negative Y component  1803 - 1   y.    
     Turning to the second pair  1806 - 2  of propulsion mechanisms  1802 - 2  and  1802 - 3 , because of the orientation of the third propulsion mechanism  1802 - 3  in the first direction and because the third propulsion mechanism  1802 - 3  is producing the third force  1803 - 3  having the first magnitude, the third force  1803 - 3  has a direction that includes a positive X component  1803 - 3   x  and a positive Y component  1803 - 3   y . Likewise, because of the orientation of the second propulsion mechanism  1802 - 2  in the second direction and because the second propulsion mechanism  1802 - 2  is producing a second force  1803 - 2  having the second magnitude, the second force  1803 - 2  has a direction that includes a negative X component  1803 - 2   x  and a positive Y component  1803 - 2   y . Summing the forces  1803 - 3  and  1803 - 2 , the resultant force  1807 - 2  for the second pair  1806 - 2  of propulsion mechanisms has a fourth magnitude, a negative X component  1807 - 2   x  that is the difference of the larger negative X component  1803 - 2   x  and the smaller positive X component  1803 - 3   x , and a positive Y component  1807 - 2   y  that is the sum of the positive Y component  1803 - 3   y  and the positive Y component  1803 - 2   y.    
     For the third pair  1806 - 3  of propulsion mechanisms  1802 - 5  and  1802 - 4 , because of the orientation of the fifth propulsion mechanism  1802 - 5  in the first direction and because the fifth propulsion mechanism  1802 - 5  is producing the fifth force  1803 - 5  having the first magnitude, the fifth force  1803 - 5  has a direction that includes a negative X component  1803 - 5   x  and a negative Y component  1803 - 5   y . Likewise, because of the orientation of the fourth propulsion mechanism  1802 - 4  in the second direction and because the fourth propulsion mechanism  1802 - 4  is producing the fourth force  1803 - 4  having the second magnitude, the fourth force  1803 - 4  has a direction that includes a positive X component  1803 - 4   x  and a negative Y component  1803 - 4   y . Summing the forces  1803 - 5  and  1803 - 4 , the resultant force  1807 - 3  for the third pair  1806 - 3  of propulsion mechanisms has the fourth magnitude, a positive X component  1807 - 3   x  that is the difference of the larger positive X component  1803 - 4   x  and the smaller negative X component  1803 - 5   x , and a negative Y component  1807 - 3   y  that is the sum of the negative Y component  1803 - 5   y  and the negative Y component  1803 - 4   y.    
     Because of the positioning of the three pairs of maneuverability components  1806 - 1 ,  1806 - 2 , and  1806 - 3 , the sum of the resultant forces  1807 - 1 ,  1807 - 2 , and  1807 - 3  results in a net force having no X component and no Y component. Likewise, the Z component of the net force is canceled out by the force of gravity. The positive Y component  1807 - 1   y  and the positive Y component  1807 - 2   y  cancel out the negative Y component  1807 - 3   y . Likewise, the positive X component  1807 - 1   x  and the positive X component  1807 - 3   x  cancel out the negative X component  1807 - 2   x . Likewise, the sum of the magnitude of the Z components of the resultant forces  1807 - 1 ,  1807 - 2 , and  1807 - 3  is equal and opposite to the force of gravity acting on the aerial vehicle  1800 . However, because the resultant forces  1807 - 1 ,  1807 - 2 , and  1807 - 3  are separated by a distance from the origin  1811 , or the center of gravity of the aerial vehicle  1811 , those forces produce a moment  1809 -Y about the Z axis, thereby causing the aerial vehicle  1800  to yaw about the Z axis. 
       FIG.  19    is a diagram of the propulsion mechanisms  1902  of the aerial vehicles discussed herein with thrust vectors  1903  to cause the aerial vehicle to roll about the X axis, when the aerial vehicle is in the VTOL orientation, in accordance with disclosed implementations. As discussed above, each of the propulsion mechanisms  1902  are approximately in the same plane, in this example, the X-Y plane and oriented in pairs  1906  as discussed above. Likewise, while the aerial vehicle may navigate in any direction, when the aerial vehicle is in the VTOL orientation,  FIG.  19    indicates a heading of the aerial vehicle  1900 . 
     In the configuration of the aerial vehicle  1900 , to cause the aerial vehicle  1900  to roll about the X axis, the first propulsion mechanism  1902 - 1 , the second propulsion mechanism  1902 - 2 , and the third propulsion mechanism  1902 - 3  generate a first force  1903 - 1 , a second force  1903 - 2 , and a third force  1903 - 3  that have approximately a same first magnitude. The fourth propulsion mechanism  1902 - 4 , fifth propulsion mechanism  1902 - 5 , and the sixth propulsion mechanism  1902 - 6  generate a fourth force  1903 - 4 , a fifth force  1903 - 5 , and a sixth force  1903 - 6  that have approximately a same second magnitude that is less than the first magnitude. 
     Each of the forces  1903 - 1 ,  1903 - 2 ,  1903 - 3 ,  1903 - 4 ,  1903 - 5 , and  1903 - 6  have an X component, a Y component, and a Z component. In this example, to cause the aerial vehicle  1900  to roll about the X axis without also surging in the X direction, swaying in the Y direction, or heaving in the Z direction, the sum of the X components of all the forces generated by the propulsion mechanisms cancel out, the sum of the Y components of all the forces generated by the propulsion mechanisms cancel out, and the sum of the Z components of all the forces generated by the propulsion mechanisms and the force of gravity cancel out. However, as discussed further below, because the forces are produced at distances from the origin and the magnitude of the Z component of the forces  1903 - 1 ,  1903 - 2 , and  1903 - 3  are larger than the magnitude of the Z component of the forces  1903 - 4 ,  1903 - 5 , and  1903 - 6 , the difference in the magnitude of the Z components of the forces and the offset from the origin  1911  result in a moment about the X axis that causes the aerial vehicle  1900  to roll about the X axis. The greater the difference between the magnitude of the combination of Z components of the first force  1903 - 1 , second force  1903 - 2 , and third force  1903 - 3  compared to the magnitude of the Z components of the fourth force  1903 - 4 , fifth force  1903 - 5 , and sixth force  1903 - 6 , the larger the moment and the more the aerial vehicle will roll about the X axis. For ease of explanation and illustration, the Z components of the individual forces have been omitted from discussion and  FIG.  19   . 
     Because of the orientation of the first propulsion mechanism  1902 - 1  in the first direction and because the first propulsion mechanism  1902 - 1  is producing a first force  1903 - 1  having the first magnitude, the first force  1903 - 1  has a direction that includes a positive X component  1903 - 1   x  and a negative Y component  1903 - 1   y . Likewise, because of the orientation of the sixth propulsion mechanism  1902 - 6  in the second direction and because the sixth propulsion mechanism  1902 - 6  is producing a sixth force  1903 - 6  having the second magnitude, the sixth force  1903 - 6  has a direction that includes a positive X component  1903 - 6   x  and a positive Y component  1903 - 6   y . Summing the forces  1903 - 1  and  1903 - 6 , the resultant force  1907 - 1  for the first pair  1906 - 1  of propulsion mechanisms has a third magnitude, a positive X component  1907 - 1   x  that is the sum of the X component  1903 - 1   x  and the X component  1903 - 6   x , and negative Y component  1907 - 1   y  that is the difference between the larger negative Y component  1903 - 1   y  and the smaller positive Y component  1903 - 6   y . In addition, the resultant force  1907 - 1  of the first pair  1906 - 1  has a positive Z component  1907 - 1   z  having a fourth magnitude in a positive Z direction. 
     Turning to the second pair  1906 - 2  of propulsion mechanisms  1902 - 2  and  1902 - 3 , because of the orientation of the third propulsion mechanism  1902 - 3  in the first direction and because the third propulsion mechanism  1902 - 3  is producing the third force  1903 - 3  having the first magnitude, the third force  1903 - 3  has a direction that includes a positive X component  1903 - 3   x  and a positive Y component  1903 - 3   y . Likewise, because of the orientation of the second propulsion mechanism  1902 - 2  in the second direction and because the second propulsion mechanism  1902 - 2  is producing a second force  1903 - 2  having the first magnitude, the second force  1903 - 2  has a direction that includes a negative X component  1903 - 2   x  and a positive Y component  1903 - 2   y . Summing the forces  1903 - 3  and  1903 - 2 , the resultant force  1907 - 2  for the second pair  1906 - 2  of propulsion mechanisms has a fifth magnitude, a negative X component  1907 - 2   x  that is the difference of the larger negative X component  1903 - 2   x  and the smaller positive X component  1903 - 3   x , and a positive Y component  1907 - 2   y  that is the sum of the positive Y component  1903 - 3   y  and the positive Y component  1903 - 2   y . In addition, the resultant force  1907 - 2  of the second pair  1906 - 2  has a positive Z component  1907 - 2   z  having a sixth magnitude in a positive Z direction that is larger than the fourth magnitude  1907 - 1   z  of the first resultant force  1907 - 1 . 
     For the third pair  1906 - 3  of propulsion mechanisms  1902 - 5  and  1902 - 4 , because of the orientation of the fifth propulsion mechanism  1902 - 5  in the first direction and because the fifth propulsion mechanism  1902 - 5  is producing the fifth force  1903 - 5  having the second magnitude, the fifth force  1903 - 5  has a direction that includes a negative X component  1903 - 5   x  and a negative Y component  1903 - 5   y . Likewise, because of the orientation of the fourth propulsion mechanism  1902 - 4  in the second direction and because the fourth propulsion mechanism  1902 - 4  is producing the fourth force  1903 - 4  having the second magnitude, the fourth force  1903 - 4  has a direction that includes a positive X component  1903 - 4   x  and a negative Y component  1903 - 4   y . Summing the forces  1903 - 5  and  1903 - 4 , the resultant force  1907 - 3  for the third pair  1906 - 3  of propulsion mechanisms has a seventh magnitude, a negative X component  1907 - 3   x  that is the difference of the larger negative X component  1903 - 5   x  and the smaller positive X component  1903 - 4   x , and a negative Y component  1907 - 3   y  that is the sum of the negative Y component  1903 - 5   y  and the negative Y component  1903 - 4   y . In addition, the resultant force  1907 - 3  of the third pair  1906 - 3  has a Z component having an eighth magnitude in a positive Z direction that is less than the sixth magnitude. 
     Because of the positioning of the three pairs of maneuverability components  1906 - 1 ,  1906 - 2 , and  1906 - 3 , the sum of the resultant forces  1907 - 1 ,  1907 - 2 , and  1907 - 3  results in a net force having no X component and no Y component. Specifically, the positive Y component  1907 - 2   y  cancels out with the negative Y components  1907 - 1   y  and  1907 - 3   y . Likewise, each of the negative X components  1907 - 2   x  and  1907 - 3   x  cancel out the positive X component  1907 - 1   x . Likewise, the sum of the magnitude of the Z components of the resultant forces  1907 - 1 ,  1907 - 2 , and  1907 - 3  is equal and opposite to the force of gravity acting on the aerial vehicle  1500 . However, because the sum of the Z components of the first force  1903 - 1 , second force  1903 - 2 , and third force  1903 - 3  is greater than the sum of the Z components of the fourth force  1903 - 4 , fifth force  1903 - 5 , and sixth force  1903 - 6 , and those forces are separated a distance from the origin, a moment  1909 -R about the X axis results that causes the aerial vehicle  1900  to roll about the X axis. 
       FIG.  20    is a block diagram illustrating an example aerial vehicle control system  2000 , in accordance with disclosed implementations. In various examples, the block diagram may be illustrative of one or more aspects of the aerial vehicle control system  2000  that may be used to implement the various systems and methods discussed herein and/or to control operation of an aerial vehicle discussed herein. In the illustrated implementation, the aerial vehicle control system  2000  includes one or more processors  2002 , coupled to a memory, e.g., a non-transitory computer readable storage medium  2020 , via an input/output (I/O) interface  2010 . The aerial vehicle control system  2000  also includes propulsion mechanism controllers  2004 , such as electronic speed controls (ESCs), power modules  2006  and/or a navigation system  2007 . The aerial vehicle control system  2000  further includes a payload engagement controller  2012 , a network interface  2016 , and one or more input/output devices  2017 . 
     In various implementations, the aerial vehicle control system  2000  may be a uniprocessor system including one processor  2002 , or a multiprocessor system including several processors  2002  (e.g., two, four, eight, or another suitable number). The processor(s)  2002  may be any suitable processor capable of executing instructions. For example, in various implementations, the processor(s)  2002  may be general-purpose or embedded processors implementing any of a variety of instruction set architectures (ISAs), such as the x86, PowerPC, SPARC, or MIPS ISAs, or any other suitable ISA. In multiprocessor systems, each processor(s)  2002  may commonly, but not necessarily, implement the same ISA. 
     The non-transitory computer readable storage medium  2020  may be configured to store executable instructions, data, flight paths, flight control parameters, center of gravity information, and/or data items accessible by the processor(s)  2002 . In various implementations, the non-transitory computer readable storage medium  2020  may be implemented using any suitable memory technology, such as static random access memory (SRAM), synchronous dynamic RAM (SDRAM), nonvolatile/Flash-type memory, or any other type of memory. In the illustrated implementation, program instructions and data implementing desired functions, such as those described herein, are shown stored within the non-transitory computer readable storage medium  2020  as program instructions  2022 , data storage  2024  and flight controls  2026 , respectively. In other implementations, program instructions, data, and/or flight controls may be received, sent, or stored upon different types of computer-accessible media, such as non-transitory media, or on similar media separate from the non-transitory computer readable storage medium  2020  or the aerial vehicle control system  2000 . Generally speaking, a non-transitory, computer readable storage medium may include storage media or memory media such as magnetic or optical media, e.g., disk or CD/DVD-ROM, coupled to the aerial vehicle control system  2000  via the I/O interface  2010 . Program instructions and data stored via a non-transitory computer readable medium may be transmitted by transmission media or signals such as electrical, electromagnetic, or digital signals, which may be conveyed via a communication medium such as a network and/or a wireless link, such as may be implemented via the network interface  2016 . 
     In one implementation, the I/O interface  2010  may be configured to coordinate I/O traffic between the processor(s)  2002 , the non-transitory computer readable storage medium  2020 , and any peripheral devices, the network interface or other peripheral interfaces, such as input/output devices  2017 . In some implementations, the I/O interface  2010  may perform any necessary protocol, timing or other data transformations to convert data signals from one component (e.g., non-transitory computer readable storage medium  2020 ) into a format suitable for use by another component (e.g., processor(s)  2002 ). In some implementations, the I/O interface  2010  may include support for devices attached through various types of peripheral buses, such as a variant of the Peripheral Component Interconnect (PCI) bus standard or the Universal Serial Bus (USB) standard, for example. In some implementations, the function of the I/O interface  2010  may be split into two or more separate components, such as a north bridge and a south bridge, for example. Also, in some implementations, some or all of the functionality of the I/O interface  2010 , such as an interface to the non-transitory computer readable storage medium  2020 , may be incorporated directly into the processor(s)  2002 . 
     The propulsion mechanism controllers  2004  communicate with the navigation system  2007  and adjust the rotational speed of each lifting propulsion mechanism and/or the propulsion mechanisms to stabilize the aerial vehicle and/or to perform one or more maneuvers and guide the aerial vehicle along a flight path. 
     The navigation system  2007  may include a global positioning system (GPS), indoor positioning system (IPS), or other similar system and/or sensors that can be used to navigate the aerial vehicle  100  to and/or from a location. The payload engagement controller  2012  communicates with the actuator(s) or motor(s) (e.g., a servo motor) used to engage and/or disengage items. 
     The network interface  2016  may be configured to allow data to be exchanged between the aerial vehicle control system  2000 , other devices attached to a network, such as other computer systems (e.g., remote computing resources), and/or with aerial vehicle control systems of other aerial vehicles. For example, the network interface  2016  may enable wireless communication between the aerial vehicle and an aerial vehicle control system that is implemented on one or more remote computing resources. For wireless communication, an antenna of the aerial vehicle or other communication components may be utilized. As another example, the network interface  2016  may enable wireless communication between numerous aerial vehicles. In various implementations, the network interface  2016  may support communication via wireless general data networks, such as a Wi-Fi network. For example, the network interface  2016  may support communication via telecommunications networks, such as cellular communication networks, satellite networks, and the like. 
     Input/output devices  2017  may, in some implementations, include one or more displays, imaging devices, thermal sensors, infrared sensors, time of flight sensors, accelerometers, pressure sensors, weather sensors, etc. Multiple input/output devices  2017  may be present and controlled by the aerial vehicle control system  2000 . One or more of these sensors may be utilized to assist in landing as well as to avoid obstacles during flight. 
     As shown in  FIG.  20   , the memory may include program instructions  2022 , which may be configured to implement the example routines and/or sub-routines described herein. The data storage  2024  may include various data stores for maintaining data items that may be provided for determining flight paths, landing, identifying locations for disengaging items, determining which maneuver propulsion mechanisms to utilize to execute a maneuver, etc. In various implementations, the parameter values and other data illustrated herein as being included in one or more data stores may be combined with other information not described or may be partitioned differently into more, fewer, or different data structures. In some implementations, data stores may be physically located in one memory or may be distributed among two or more memories. 
     Those skilled in the art will appreciate that the aerial vehicle control system  2000  is merely illustrative and is not intended to limit the scope of the present disclosure. In particular, the computing system and devices may include any combination of hardware or software that can perform the indicated functions. The aerial vehicle control system  2000  may also be connected to other devices that are not illustrated, or instead may operate as a stand-alone system. In addition, the functionality provided by the illustrated components may, in some implementations, be combined in fewer components or distributed in additional components. Similarly, in some implementations, the functionality of some of the illustrated components may not be provided and/or other additional functionality may be available. 
     Those skilled in the art will also appreciate that, while various items are illustrated as being stored in memory or storage while being used, these items or portions of them may be transferred between memory and other storage devices for purposes of memory management and data integrity. Alternatively, in other implementations, some or all of the software components may execute in memory on another device and communicate with the illustrated aerial vehicle control system  2000 . Some or all of the system components or data structures may also be stored (e.g., as instructions or structured data) on a non-transitory, computer-accessible medium or a portable article to be read by an appropriate drive, various examples of which are described herein. In some implementations, instructions stored on a computer-accessible medium separate from the aerial vehicle control system  2000  may be transmitted to the aerial vehicle control system  2000  via transmission media or signals such as electrical, electromagnetic, or digital signals, conveyed via a communication medium such as a wireless link. Various implementations may further include receiving, sending, or storing instructions and/or data implemented in accordance with the foregoing description upon a computer-accessible medium. Accordingly, the techniques described herein may be practiced with other aerial vehicle control system configurations. 
     The above aspects of the present disclosure are meant to be illustrative. They were chosen to explain the principles and application of the disclosure and are not intended to be exhaustive or to limit the disclosure. Many modifications and variations of the disclosed aspects may be apparent to those of skill in the art. Persons having ordinary skill in the field of computers, communications, and speech processing should recognize that components and process steps described herein may be interchangeable with other components or steps, or combinations of components or steps, and still achieve the benefits and advantages of the present disclosure. Moreover, it should be apparent to one skilled in the art that the disclosure may be practiced without some or all of the specific details and steps disclosed herein. 
     While the above examples have been described with respect to aerial vehicles, the disclosed implementations may also be used for other forms of vehicles, including, but not limited to, ground based vehicles and water based vehicles. 
     Aspects of the disclosed system may be implemented as a computer method or as an article of manufacture such as a memory device or non-transitory computer readable storage medium. The computer readable storage medium may be readable by a computer and may comprise instructions for causing a computer or other device to perform processes described in the present disclosure. The computer readable storage media may be implemented by a volatile computer memory, non-volatile computer memory, hard drive, solid-state memory, flash drive, removable disk and/or other media. In addition, components of one or more of the modules and engines may be implemented in firmware or hardware. 
     Unless otherwise explicitly stated, articles such as “a” or “an” should generally be interpreted to include one or more described items. Accordingly, phrases such as “a device configured to” are intended to include one or more recited devices. Such one or more recited devices can also be collectively configured to carry out the stated recitations. For example, “a processor configured to carry out recitations A, B and C” can include a first processor configured to carry out recitation A working in conjunction with a second processor configured to carry out recitations B and C. 
     Language of degree used herein, such as the terms “about,” “approximately,” “generally,” “nearly” or “substantially” as used herein, represent a value, amount, or characteristic close to the stated value, amount, or characteristic that still performs a desired function or achieves a desired result. For example, the terms “about,” “approximately,” “generally,” “nearly” or “substantially” may refer to an amount that is within less than 10% of, within less than 5% of, within less than 1% of, within less than 0.1% of, and within less than 0.01% of the stated amount. 
     As used throughout this application, the word “may” is used in a permissive sense (i.e., meaning having the potential to), rather than the mandatory sense (i.e., meaning must). Similarly, the words “include,” “including,” and “includes” mean including, but not limited to. Additionally, as used herein, the term “coupled” may refer to two or more components connected together, whether that connection is permanent (e.g., welded) or temporary (e.g., bolted), direct or indirect (e.g., through an intermediary), mechanical, chemical, optical, or electrical. Furthermore, as used herein, “horizontal” flight refers to flight traveling in a direction substantially parallel to the ground (e.g., sea level), and that “vertical” flight refers to flight traveling substantially radially outward from the earth&#39;s center. It should be understood by those having ordinary skill that trajectories may include components of both “horizontal” and “vertical” flight vectors. 
     Although the invention has been described and illustrated with respect to illustrative implementations thereof, the foregoing and various other additions and omissions may be made therein and thereto without departing from the spirit and scope of the present disclosure.