Patent Publication Number: US-11378972-B2

Title: Autonomous modular sweeper robot

Description:
CLAIM OF PRIORITY 
     This application is a Continuation of U.S. patent application Ser. No. 16/247,482, filed on Jan. 14, 2019, and entitled “Autonomous Modular Robot”, which is a Continuation of U.S. patent application Ser. No. 15/152,100, filed May 11, 2016 (U.S. Pat. No. 10,180,685, issued on Jan. 15, 2019), entitled, “Autonomous Modular Robot”, wherein U.S. patent application Ser. No. 15/152,100 is a continuation-in-part of U.S. patent application Ser. No. 14/937,633, filed Nov. 10, 2015, entitled “Modular Robot”, and claims the priority benefit under 35 U.S.C. § 119(e) of U.S. Provisional Patent Application No. 62/160,059, filed May 12, 2015; and U.S. Provisional Patent Application No. 62/200,814, filed Aug. 4, 2015, all of which are herein incorporated by reference. 
    
    
     FIELD 
     The present disclosure relates generally to a multifunctional robot and, more specifically, to a modular robot configured to accept a plurality of interchangeable attachments that may be configured to perform a variety of functions. 
     BACKGROUND 
     Autonomous robots are becoming increasingly prevalent due to their ability to automatically perform a variety of tasks that are typically performed manually by humans, or that have been performed with direct human control of a robot. A simple example of an autonomous robot is a robotic floor cleaner such as a robotic vacuum or a robotic mop. These robots are often programmable, allowing users to configure operation times, frequency of operation, and various other settings for the robots. Once programmed, the robots may perform a task, move, and interact with the surrounding environment without requiring further human input. While such robots are becoming more prevalent, the robots are often designed to perform only a single function, such as to clean a surface. As a result, performing a variety of tasks may be difficult and/or prohibitively expensive due to the need to acquire a dedicated autonomous robot for each task that the user wishes to complete. 
     SUMMARY 
     In some embodiments, an autonomous modular robot is provided. The robot comprises a main body; a drive system attached to the main body; an attachment retention system; and a control system. The drive system is configured to move the main body. The attachment retention system is configured to couple two or more interchangeable attachments to the main body, and each of the interchangeable attachments may be configured to perform a task. The control system may be configured to autonomously control the drive system and the interchangeable attachments upon coupling of the interchangeable attachments to the main body. The robot may also include a lift mechanism that allows the interchangeable attachments to be moved, e.g., vertically open and down, laterally back-and-forth, or tilted from side to side, all while the robot remains stationary or in combination with movement of the robot. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a front perspective view of an example of an autonomous robot according to some embodiments. 
         FIGS. 1B-1C  are rear perspective views of an example of an autonomous robot, with a loaded and unloaded power supply, respectively, according to some embodiments. 
         FIGS. 2A-2D  are examples of top-down, perspective, back, and side views of the autonomous robot of  FIG. 1A . 
         FIG. 3  is an example of a schematic diagram depicting electronic connections for an autonomous robot according to some embodiments. 
         FIG. 4  is an example of a schematic diagram depicting electrical connections for a primary power supply according to some embodiments. 
         FIG. 5  is an example of a schematic diagram depicting electrical connections for a secondary power supply according to some embodiments. 
     
    
    
     The drawings are provided to illustrate example of embodiments and are not intended to limit the scope of the disclosure. In addition, features in the drawings are not necessarily to scale. 
     DETAILED DESCRIPTION 
     In some embodiments, an autonomous modular robot includes an attachment retention system that allows the robot to simultaneously retain two or more interchangeable attachments for performing tasks. The interchangeable attachments may each be configured to perform a unique task, e.g., steam cleaning, vacuuming, grass cutting, polishing, polishing, driveway and/or street cleaning (e.g., sweeping), package grasping and/or moving, etc. In some embodiments, the interchangeable attachments may be retained such that they are disposed sequentially in the path of travel of the robot. For example, a first interchangeable attachment may be retained directly in front of a second interchangeable attachment, with both interchangeable attachments being in the same line on the path of travel of the robot. The interchangeable attachments may be configured to perform complementary tasks. For example, for cleaning a floor, the first interchangeable attachment may be configured to vacuum the floor and the second interchangeable attachment may be configured to steam clean the floor. 
     Preferably, the interchangeable attachments may be automatically loaded and unloaded from the robot at a docking or base station. The loading and unloading may be performed autonomously, with the robot automatically aligning itself and loading or unloading an interchangeable attachment as needed to accomplish the job assignment that the robot has been programmed to perform. 
     In some embodiments, the robot may include a lift mechanism that may be translated vertically, tilted, rotated, and/or moved forwards or backwards. The lift mechanism may include the attachment retention system, thereby allowing the interchangeable attachments to be moved vertically. This vertical movement may be utilized as part of perform a task and/or to accommodate interchangeable attachments of different sizes. 
     It will be appreciated that movement of the lift mechanism access or retention of interchangeable attachments may change the physical dimensions of the robot. Such a change in dimensions may impact the movement of the robot and the robot&#39;s clearance with obstacles in its path. Preferably, the lift mechanism includes a dimension sensor proximate a top of the lift mechanism. The dimension sensor may be utilized to determine the size, e.g., a height and/or a width of the robot with any retained interchangeable attachments, to help navigate the robot and avoid obstacles. 
     Advantageously, the robot allows for its functionality to completely change using the interchangeable attachments. Moreover, the ability to provide multiple attachments may increase the effectiveness of the robot in performing certain assignments. For example, the attachments may perform complementary tasks (were performing one task increases the efficacy of performing another task) to more effectively accomplish a particular assignment, such as cleaning a floor. In addition, the lift mechanism allows for both the ability to perform tasks that require vertical movement and the ability to accommodate a wide range of attachments having different heights. In some embodiments, the dimension sensor advantageously maintains the compactness of the device by allowing a single sensor that may aid both operation and navigation of the device. 
     Reference will now be made to the drawings, in which like reference numerals refer to like parts throughout. 
       FIG. 1A  shows an example of a perspective view of an autonomous modular robot  100 . The robot  100  includes a main body  1 , interchangeable attachments  4   a  and  4   b , a drive system  7 , a front support system  10  for supporting the front end of the robot off the ground, an electronic control system  13 , and a primary power supply  17 . The main body  1  functions as a base or frame onto and within which the remaining components may be situated and attached. The drive system  7  is mounted to the main body  1 , adjacent to a back end  3  of the main body  1 . In some embodiments, the back end  3  may correspond to the front end of the robot  100 ; that is, the robot  100  may be configured to typically travel in a direction such that the back end  3  is at the front of the robot  100 . 
     With continued reference to  FIG. 1A , the drive system  7  provides mobility to the robot  100  across an underlying surface. In some embodiments, the drive system  7  includes wheels  8 . Rotation of these wheels  8  allows the main body  1  to traverse a surface. The support system  10  may be mounted to the main body  1 , offset from the drive system  7 , e.g., the support system  10  may be positioned proximate an opposite end of the robot  100  from the wheels  8 . In some embodiments, the support system  10  may include a rotatable or non-rotatable wheel  11 , e.g., two spaced-apart wheels arranged on different sides of interchangeable attachments  4   a ,  4   b . In some other embodiments, the support system  10  may omit wheels and include one or more low friction pads for contacting and sliding across a surface. 
     In some embodiments where the wheel  11  is rotatable, the support system  10  may function as a steering system, with rotatable wheels that turn and point in different directions as desired. In such embodiments, the support system  10  may help the robot  100  to navigate across a surface and may aid functions such as turning and changing the direction of travel of the robot  100 . As such, the support system  10  may aid in changing the lateral direction in which the robot is moving when moving in a forward direction as well as in a backward direction. In some embodiments, both the support system  10  and the drive system  7  may have rotatable wheels, which may be used to increase the mobility of the robot  100 , while decreasing the turning radius of the robot  100 . 
     The interchangeable attachments  4   a ,  4   b  provide a level of modularity and variety of functionality to the robot  100 . In some embodiments, the interchangeable attachments  4   a ,  4   b  allows the functionality and utility of the robot  100  to be entirely changed, depending upon the attachments  4   a ,  4   b  that are coupled to the main body  1 . As shown in  FIG. 1A , the interchangeable attachments  4   a ,  4   b  may be removably mounted to the main body  1  to alter the functionality of the robot  100  as desired. 
     In some embodiments, the robot  100  includes a laterally extending support structure  110  mounted to the main body  1  and configured to retain the interchangeable attachments  4   a ,  4   b . In some embodiments, the laterally extending support structure  110  may take the form of a bar or rail having a channel  18  into which a corresponding protrusion  120   a  or  120   b  may fit. This channel  18  provides a cavity into which the interchangeable attachments  4   a ,  4   b  may be mounted. The interchangeable attachments  4   a ,  4   b  may be operatively engaged into the attachment retention channel  18 . This allows the attachment retention channel  18  to be used to structurally secure the interchangeable attachments  4   a ,  4   b  and for the interchangeable attachments  4   a ,  4   b  to be easily removed from the main body  1  when altering the functionality of the robot  100 . In some embodiments, the attachments  4   a ,  4   b  may be installed or removed by simply sliding into or out of, respectively, the retention channel  18 . As an example, the protrusions  120   a ,  120   b  have a T-shaped cross-sectional profile, which fits into a T-shaped open volume in the channel  18 . The attachment retention channel  18  may include a mechanism, e.g. a latch, for securing the interchangeable attachments  4   a ,  4   b  in place once the interchangeable attachments  4   a ,  4   b  is mounted. Thus, the attachment retention channel  18  enables the interchangeable attachments  4   a ,  4   b  to be coupled to the main body  1  and to securely hold the interchangeable attachments  4   a ,  4   b  in place during operation of the robot  100 . Additionally, the attachment retention channel  18  may include sensors to ensure that the interchangeable attachments  4   a ,  4   b  are properly aligned for mounting. 
     The attachment retention channel  18  may traverse substantially an entire length of the support  110 . Advantageously, the lateral extension of the retention channel  18  allows multiple attachments  4   a ,  4   b  to be coupled to the main body  1 , and also allows for additional interchangeable attachments to be coupled to the main body  1 . For example, to accommodate additional interchangeable attachments, the support structure  110  may simply be lengthened. In some embodiments, the support structure  110  may be detachable and a support structure of an appropriate length may be installed depending upon the dimensions of and/or the number of interchangeable attachments that will be coupled to the main body  1 . In some other embodiments, counterweights (not illustrated) may be attached proximate to the end  3  of the robot  100  to balance the robot  100 . In some embodiments, the robot  100  may be configured to accommodate two or more, or 3 or more, interchangeable attachments. 
     In some embodiments, the support structure  110  is mounted to a lift mechanism  130 , which can be moved vertically. The lift mechanism  130  may move to change the vertical height of the interchangeable attachments  4   a ,  4   b  after retaining those attachments in the support structure  110 , and/or may be moved to accommodate the heights of different attachments  4   a    4   b . In some embodiments, in addition to or as an alternative to vertical movement, the lift mechanism may tilt and/or rotate to, e.g., lift up a side, back, and/or front of a retained interchangeable attachment  4   a ,  4   b.    
     In some embodiments, the lift mechanism may also include an actuator  160  for extending the support structure  110  laterally. Such lateral extension may be used to accommodate deeper interchangeable attachments  4   a ,  4   b  and/or to move objects that are being manipulated by the robot  100 . For example, in some embodiments, one or more of the interchangeable attachments  4   a ,  4   b  may include an adapter or grasping device for holding an object. The lift mechanism may be utilized to move this object vertically, laterally, and/or to tilt the object. 
     With continued reference to  FIG. 1A , the electronic control system  13  may be configured to control the robot  100  during operation. In some embodiments, the electronic control system  13  may be mounted on the main body  1 , adjacent to the drive system  7 , between the wheels  8 . The electronic control system  13  may thus be protected within the main body  1  from the external environment, including collisions with objects in the external environment. 
     An example of electronic connections for the electronic control system  13  is schematically shown in  FIG. 3 . The electronic control system  13  may be wired to the drive system  7 , or alternatively, control over the drive system  7  may be wirelessly established using the wireless communications module  16 . The electronic control system  13  may also be configured to communicate with the interchangeable attachments  4   a ,  4   b  in order to regulate the various functions of the robot  100  that are available using the interchangeable attachments  4   a ,  4   b . As such, the electronic control system  13  may be electronically connected to the drive system  7 , and the interchangeable attachments  4   a ,  4   b  in order to enable the electronic control system  13  to regulate the drive system  7 , as well as the interchangeable attachments  4   a ,  4   b  during operation of the robot  100 . In embodiments where the support system  10  includes active components, such as embodiments where the support system  10  functions as a steering system, the electronic control system  13  may also be connected (via wired and/or wireless connections) to the support system  10 . The connection allows the electronic control system  13  to control the support system  10 , e.g., thereby allowing changes in the direction and/or rotation of one or more wheels of the support system. 
     With continued reference to  FIG. 3 , the interchangeable attachments  4   a ,  4   b  may comprise a secondary control unit  5  and a wireless transceiver  6 . The wireless communications module  16  of the electronic control system  13  allows communications with the wireless transceiver  6 . In turn, the wireless transceiver  6  may be in electrical communication with the secondary control unit  5  of the interchangeable attachment. Thus, the primary control unit  15  may control the drive system  7  (and the support system  10  in embodiments where the support system  10  includes active components), as well as the interchangeable attachments  4   a ,  4   b  through the secondary control unit  5 . The wireless communications module  16  and the wireless transceiver  6  enable wireless communication between the electronic control system  13  and the interchangeable attachments  4   a ,  4   b . Additionally, the wireless communications module  16  allows the electronic control system  13  to receive commands from an external source such as a user computing device through a network, e.g., Wi-Fi, Bluetooth, etc. In some embodiments, the wireless communications module  16  enables remote user control or programming of the robot  100 . The wireless communications module  16  may be communicatively coupled to the wireless transceiver  6  and commands may be wirelessly transmitted from the electronic control system  13  to the interchangeable attachments  4   a ,  4   b . The wireless transceiver  6  may be electronically connected to the secondary control unit  5 . Commands that are wirelessly received from the electronic control system  13  may thus be implemented through the secondary control unit  5 , allowing the electronic control system  13  to wirelessly control the interchangeable attachments  4   a ,  4   b . The wireless transceiver  6  additionally enables the interchangeable attachments  4   a ,  4   b  to wirelessly communicate with other ones of the interchangeable attachments  4   a ,  4   b , to allow the execution of tasks to be coordinated. The wireless communications module  16  and the wireless transceiver  6  may additionally allow for system updates to be downloaded and applied to the primary control unit  15  and/or the secondary control unit  5 . Such system updates may be accepted and implemented wirelessly through a user computing device. 
     In some embodiments, rather than wireless communications, a physical connection may be made between the interchangeable attachment and electronic control system. For example, the wireless communications module  16  and the transceiver  6  may simply be communications units that are connected together by wiring. In some embodiments, electrodes may be present in the attachment retention channel  18  and the protrusions  120   a ,  120   b . Once locked into place inside the retention channel  18 , the electrodes on the protrusions  120   a ,  120   b  may mate and provide electrical contact with corresponding electrodes in the retention channel  18 , thereby forming a communications channel between the electronic control system  13  and the interchangeable attachment  4   a  or  4   b.    
     Referring again to  FIG. 1A , the primary power supply  17  provides electrical power to the robot  100 . Non-limiting examples of power supplies for the power supply  17 , or any of the other power supplies disclosed herein, include stand-alone power supplies such as batteries, including rechargeable in non-rechargeable batteries. Examples of rechargeable batteries include NiMH or Li-ion batteries. In some embodiments, the primary power supply  17  includes a transformer and is connected to a power outlet, e.g., an AC power outlet. 
     The primary power supply  17  may be externally and removably mounted to the main body  1 , opposite to the interchangeable attachments  4   a ,  4   b . Such a configuration may allow the primary power supply  17  to act as a counterbalance to the interchangeable attachments  4   a ,  4   b . The primary power supply  17  may be removed from the main body  1  and replaced when the primary power supply  17  is depleted. The primary power supply  17  may additionally be positioned in a manner such that the primary power supply  17  may be recharged without removing the primary power supply  17  from the main body  1  by docking the robot to a charging station (not illustrated). As shown in  FIG. 4 , the primary power supply  17  may be electrically connected to the drive system  7  and the interchangeable attachments  4   a ,  4   b , providing electrical power to transport the robot  100  as well as to perform a variety of functions using the interchangeable attachments  4   a ,  4   b.    
     A fastening mechanism for holding the primary power supply  17  in place on the main body  1  may be provided in order to secure the primary power supply  17  in place.  FIGS. 1B-1C  are rear perspective views of an example of an autonomous robot, with a loaded and unloaded power supply, respectively. For ease of illustration, these figures do not include the interchangeable attachments  4   a ,  4   b . As illustrated, the power supply  17  may be fastened to the main body  1  by attachment to slots  150  of the main body  1 . In some embodiments, the slots  150  may be part of vertical extensions  140 . The slots  150  may be shaped to mate with a corresponding protrusion  17   a  on the power supply  17 . In some embodiments, multiple slots  150  may be provided to accommodate multiple power supplies  17 . In addition, the slots  150  may be utilized to hold functional attachments, e.g., additional interchangeable attachments for performing tasks, and/or counterweights to the interchangeable attachments or power supply  17 . 
     It will be appreciated that the robot  100  may accommodate a plurality of power supplies. For example, with reference again to  FIG. 3  and now also to  FIG. 5 , the electronic control system  13  may include a secondary power supply  14  in addition to the primary control unit  15 . The secondary power supply  14  provides electrical power to the electronic control system  13  and may also be electrically connected to the drive system  7 , the support system  10  (in embodiments where the support system  10  includes active components that require power), the interchangeable attachments  4   a ,  4   b , and the primary control unit  15 . The secondary power supply  14  provides electrical power to the drive system  7 , the support system  10  (again where the support system  10  includes active components that require power), and the interchangeable attachments  4   a ,  4   b  in order to enable the robot  100  to remain operational while the primary power supply  17  is replaced upon depletion. The secondary power supply  14  additionally enables the robot  100  itself to replace the primary power supply  17  by providing electrical power and keeping the robot operational when the primary power supply  17  is depleted or removed. 
     With reference now to  FIGS. 2A-2D , examples of top-down, perspective, back, and side views, respectively, of the robot  100  are illustrated. As shown in  FIG. 2A , the drive system  7  comprises a pair of drive wheels  8  and at least one motor  9 . The pair of drive wheels  8  allows the robot to traverse across a surface while the at least one motor  9  converts electrical energy from the primary power supply  17  and the secondary power supply  14  into mechanical energy, e.g., the location of the wheels  8 . The pair of drive wheels  8  may be torsionally connected to the at least one motor  9 , enabling rotation of the pair of drive wheels  8  due to mechanical energy provided by the at least one motor  9 . Preferably, the pair of drive wheels  8  is a pair of geared wheels. In some embodiments, each drive wheel from the pair of drive wheels  8  may be driven by its own motor  9 . Preferably, the at least one motor  9  includes a gearbox (not illustrated) as well as one or more sensors. The gearbox is configured to alter the torque output of the at least one motor  9  while the sensors are able to monitor the at least one motor  9  as well as to relay data to the electronic control system  13  to facilitate movement of the robot  100 . 
     With continued reference to  FIGS. 2B-2D , in embodiments where the support system  10  functions as a steering system, the system may comprise a first rotatable wheel  11  and a second rotatable wheel  12 . In some embodiments, these wheels  11 ,  12  may be mounted on frame extensions  1   a ,  1   b , respectively, of the main body  1 . As illustrated, these frame extensions  1   a ,  1   b  also define an open volume into which the interchangeable attachments  4   a ,  4   b  may be accommodated. 
     The first rotatable wheel  11  and the second rotatable wheel  12  enable the robot to change direction when traveling across a surface. The first rotatable wheel  11  and the second rotatable wheel  12  are mounted proximate to the front end  120  ( FIG. 2D ), opposite to the drive system  7  along the back end  3 . The first rotatable wheel  11  and the second rotatable wheel  12  are thus offset from the drive system  7  and are configured to alter the lateral direction of movement of the robot  100 . In some embodiments, the electronic control system  13  is configured to navigate the robot  100  via control of the first rotatable wheel  11  and the second rotatable wheel  12 . In some embodiments, the first rotatable wheel  11  and the second rotatable wheel  12  are caster wheels. 
     In some embodiments, a first tread is wrapped around one wheel of the pair of drive wheels  8  to the first rotatable wheel  11 , and a second tread is wrapped around the other wheel from the pair of drive wheels  8  to the second rotatable wheel  12 . When present, these treads enable the robot to traverse across more varied or slippery terrain such as snow and ice. In some embodiments, the robot is thus provided mobility in a similar fashion as a tank. 
     With reference again to  FIG. 4 , in some embodiments, the robot may also include a plurality of lighting units  19 . The plurality of lighting units  19  may be configured to provide illumination in the vicinity of the robot. In some embodiments, the plurality of lighting units may be mounted to the main body  1 , proximate to the back end  3 . The plurality of lighting units  19  may be adjustable from side to side or up and down. Additionally, the plurality of lighting units  19  may be configured to provide illumination in multiple directions simultaneously. As shown in  FIG. 4 , the plurality of lighting units  19  may be electrically connected to the primary power supply  17 , enabling the primary power supply  17  to provide electrical power to the plurality of lighting units  19 . The specific location of the plurality of lighting units  19  may vary as desired in order to suit the functionality and design of the robot  100 . For example, the plurality of lighting units  19  may be a plurality of light-emitting diodes (LEDs) that are built directly into the main body  1  in some embodiments. 
     Because the robot  100  is configured for autonomous operation, it is desirable that it does not become stuck, damaged, or otherwise compromised during operation. With continued reference to  FIGS. 2A-2D , the robot  100  may further include one or more sensors  20 . The one or more sensors  20  facilitate the autonomous operation of the robot by assisting in its movement. In some embodiments, the one or more sensors  20  are collision detection sensors. In some embodiments, the one or more sensors  20  may be one or more of infrared or other proximity sensors, ground sensors, or line detection sensors. The one or more sensors  20  may be configured to detect if the robot is on a collision course with an object. The one or more sensors  20  may then provide a signal to warn the electronic control system  13  of the impending collision, thereby enabling actions to be taken to prevent a collision. For example, in embodiments where the support system  10  is a steering system, the electronic control system  13  may instruct the support system  10  to steer the robot  100  away from the object. In some embodiments, the area in which the robot  100  is to work may include beacons to help the robot  100  navigate. For example, the work area may include Bluetooth beacons or infrared light emitters, which are detected by the one or sensors  20 . 
     The one or more sensors  20  may be positioned on a front end  2  of the main body  1 , enabling the one or more sensors  20  to detect an object in front of the robot as it is traveling across a surface. The plurality of sensors  20  is electronically connected to the electronic control system  13 . As such, the one or more sensors  20  are able to communicate with the electronic control system  13  as shown in  FIG. 4 , allowing the electronic control system  13  to take actions to avoid a collision. The robot  100  may additionally include a bumper (not illustrated) for absorbing impacts. Additional sensors such as bump sensors (not illustrated) may be included in order to determine if the robot  100  has made contact with an object. 
     In some embodiments, the one or more sensors  20  may include at least one camera to provide a live view of the vicinity of the robot  100 . Preferably, the camera is mounted proximate the highest point on the robot  100 . In some embodiments, the camera is mounted on the lift mechanism  130 , e.g., at a top of the lift mechanism. In addition, preferably, the camera is stationary, e.g., is mounted on a part of lift mechanism that does not move vertically or laterally relative to the main body  1  of the robot  100 . In this position, the camera may be utilized to view both the ambient environment and the robot  100 . In some embodiments, the robot  100  includes two or more cameras, e.g., one facing forward and one facing backwards. The forward facing camera may scan for obstacles in the path of the robot  100 , while the backwards-facing camera may scan for obstacles when the robot  100  is moving backwards. In addition, the backwards-facing camera may be configured to image the interchangeable attachments  4   a ,  4   b , and the robot  100  may be configured to use this information to determine the number and/or sizes of the attachments  4   a ,  4   b . Such a determination may be useful to prevent the tops, e.g., the top corners, of the attachments  4   a ,  4   b  from colliding with elevated obstacles. In some embodiments, the camera may be utilized to detect objects, colors, and additional visual factors that aid in autonomous operation of the robot  100 . For example, the color green may correspond to grassy terrain while the color blue may correspond to water, allowing the robot to steer away from the water and remain on the grassy terrain. The camera may additionally include infrared imaging, night vision, and/or similar imaging technologies for emitting and detecting light of the emitted wavelength. Thus, the camera may be used as a dimension sensor to determine the size of the robot  100 , including the attachments  4   a ,  4   b.    
     As disclosed herein, the interchangeable attachments  4   a ,  4   b  may provide a variety of functionality for the robot  100 . In some embodiments, the interchangeable attachments  4   a ,  4   b  may include a vacuum cleaner. The vacuum cleaner may be utilized to remove dust, debris, and other small objects from a surface as the robot travels across the surface. In some embodiments, the interchangeable attachments  4   a ,  4   b  may include a steam cleaner. The steam cleaner may be configured to clean the surface across which the robot  100  travels. The interchangeable attachments  4   a ,  4   b  may include a lawnmower. The lawnmower may be configured to cut plant growth while traveling over the growth. In some embodiments, the interchangeable attachments  4   a ,  4   b  may include or may be an additional power supply. The additional power supply may be configured to provide electrical power to the robot  100  beyond the capacity provided by the primary power supply  17  and the secondary power supply  14  (were provided). The additional power supply may be electrically connected to the drive system  7 , the support system  10  (in embodiments where the support system  10  includes active components that require power), and the electronic control system  13 . 
     It will be understood that the interchangeable attachments  4   a ,  4   b  may include additional components that serve to facilitate the various functions of those attachments. For example, in the case of a lawnmower, the interchangeable attachments  4   a ,  4   b  may include a motor as well as an attached blade. It will also be understood that the shape and overall design of the interchangeable attachments  4   a ,  4   b  may vary according to the functionality or task to be performed by the interchangeable attachments  4   a ,  4   b . Additional example tasks include, but are not limited to, road painting, transporting goods, and ice resurfacing. The robot  100  may additionally be utilized for military applications such as chemical detection, mine detection, and explosive ordnance disposal (EOD). In addition, the interchangeable attachments  4   a ,  4   b  may be an adapter that allows the robot to pick up an object that the adapter is designed to accommodate. Example objects that may be picked up via the adapter include, but are not limited to, garbage containers and clothes bins. 
     As illustrated in  FIG. 1A , the interchangeable attachments  4   a ,  4   b  may be disposed sequentially in the path of travel of the robot  100 . For example, the interchangeable attachments  4   a ,  4   b  may be arrayed one in front of the other, with the interchangeable attachment  4   a  behind the interchangeable attachment  4   b  closer to the back end  3  of the robot  100 . 
     Preferably, the tasks performed by the interchangeable attachments  4   a ,  4   b  are complementary, with one attachment serving to increase the efficacy of the other attachment in performing a task. For example, the interchangeable attachment  4   a  may be a vacuum and the interchangeable attachment  4   b  may be a steam cleaner. As another example, the interchangeable attachment  4   a  may be a vacuum or a steam cleaner, and the interchangeable attachment  4   b  may include a paint dispenser for painting an underlying surface. As yet another example, one of the interchangeable attachments may be an empty container, and the other of the interchangeable attachments may be a device that receives or generates material that requires a volume for storage. In some embodiments, the device generating the material needing storage may be a street sweeper or lawn mower, and the empty container may be used to hold, e.g., material swept up by the sweeper or grass cuttings generated by the lawn mower. When the container is filled, the robot  100  may be configured to switch out the filled container with an empty container, e.g., at a base station. 
     In some embodiments, the electronic control system  13  may include a digital display (not illustrated) for enabling the user of the robot  100  to view various settings and properties of the robot. The digital display may incorporate touch technology for user input into the electronic control system  13  and/or a physical input device such as a keypad may be present. The display may serve as part of an interface that allows the user to input commands as well as configure the electronic control system  13  and/or the interchangeable attachments  4   a ,  4   b . The electronic control system  13  may further incorporate a microphone to enable the user to input voice commands during operation of the robot. A data storage device may be present as well to allow data collected during operation of the robot to be saved. The data storage  15  may or may not be removable from the robot  100 . Data storage ports such as Universal Serial Bus (USB) ports may be present to facilitate data transfer or to allow the robot  100  to be connected to an external computing device. Additionally, the robot  100  may further include a charging port to allow it to be physically connected to an external power source for charging. 
     As previously discussed, because the primary power supply  17  is externally mounted to the main body  1 , the robot  100  may be capable of replacing the primary power supply  17  autonomously in lieu of manual replacement by the user. The robot  100  may be utilized in conjunction with a docking station or similar structure for charging and/or replacing the primary power supply  17 . The robot  100  may be configured to autonomously dock with the docking station in order to charge the primary power supply  17 . The interchangeable attachments  4   a ,  4   b  may be docked to and charged at the docking station as well. This allows the secondary power supply  14  to be charged via the docking station in addition to the primary power supply  17 . 
     Advantageous, robots according to various embodiments disclosed herein may run indefinitely, with the robot constantly swap batteries and interchangeable attachments as the need arises and as job assignments change. As a result, the robot may function as a home cleaning robot, a commercial cleaning robot, an outdoor robot, an indoor robot, etc. which may autonomously change its abilities without the need of human interaction (e.g., from grass cutting with a grass cutting attachment, to moving bins and crates of an adapter for supporting bins and crates, to cleaning driveways with a vacuum and/or sweeping attachment). An example of the operation of the robot is provided below. It will be appreciated that the sequence below maybe performed in the order shown. In addition, omissions of certain actions and/or changes in the order of various actions are also contemplated.
     1. The robot may start off at a charging base station with an interchangeable attachment (e.g., a vacuum module) locked to the main chassis or body of the robot through its retention system.   2. The robot may start off with a power supply (e.g., a removable battery) already in place.   3. The robot heads out of the charging base to perform its assignment (in this case vacuuming).   4. When the robot is finished with the assignment, or when the interchangeable attachment is filled to capacity (e.g., when a vacuum module is filled with dust) the robot will return to the base station or another designated drop area, and detach the interchangeable attachment. The detachment may occur via unlock and pushout of the attachment, or by dropping the attachment under the force of gravity.   5. The robot aligns itself to the back of the interchangeable attachment, or wherever the retention adapters are among the interchangeable attachments, moves forwards towards the interchangeable attachment, centers itself (e.g., using sensors such as a camera) and the retention system locks/unlocks the interchangeable attachment as desired. When the robot approaches the base/charging station, at a certain distance is starts a docking procedure. The robot maintains a docking distance from the base station to help itself align to the back of the modular box as well as to the retention system before the robot docks.   6. This docking procedure exists in both retaining and detaching the interchangeable attachments at a designated area or a base/charging station.   7. The base station may help guide the robot via sensors and buttons to dock at the base station and aligned with the retention system. In other words, the base station may provide guidance for the robot to return to the station. In addition, the station may include an actuator that shifts the position of the interchangeable attachment to align with the retention system of the robot.   8. The robot may move towards and locate the base station with a variety of sensors, such as live feed cameras, infrared or other proximity sensors, ground sensors, or line detection sensors that are able to follow “tracks” which may be provided on the ground along the path which the robot is to traverse. The tracks may be, e.g., anything from tape to paint sensors located on the ground.   9. The robot may use a variety of sensors such as live feed cameras and/or infrared or other proximity sensors to help locate, and load and unload the interchangeable attachments at a base station or other designated area.   10. The robot may move to an empty location (e.g., at the base station or at a designated area) and detach its interchangeable attachment. Preferably, this detachment occurs at the location the interchangeable attachment was originally picked up from, e.g., at the space left open when the component was earlier retained by the robot.   11. The robot may then move to another interchangeable attachment for another task. For example, the robot may align itself with a steam cleaning interchangeable attachment located at the base station (e.g., next to or around the vacuum interchangeable attachment), and pick up the steam cleaning interchangeable attachment via the retention system, and then move away from base station to perform the steam cleaning task. In some other embodiments, both the vacuum attachment and the steam cleaning attachment may be loaded onto the robot such that vacuuming and steam cleaning maybe performed without requiring the robot to return to the base station to switch attachments.   12. The robot can navigate with the help of GPS, in addition to other location devices not positioned on the robot itself or the base station to help with returning to an interchangeable attachment for docking and undocking. These are location devices may include Bluetooth beacons or infrared light emitters.   13. In cases where the robot is equipped with a modular, removable power supply, the power supply may be unloaded and a new power supply may be loaded in a procedure similar to the unloading and loading of interchangeable attachments. For example, where the robot has perform various tasks and its attached battery is running low, the robot may: move to a base station containing a charged or charging battery, unload a depleted battery at the base station or designated area, and load another battery.   14. In cases where the robot is not equipped with a modular, removable power supply, the robot may use a variety of sensors to return to the base station for recharging. The robot may return to the base station to recharge, head off to finish its job, or remain at the base station depending on whether a job assignment has been completed.   15. The robot may be charged while retaining an interchangeable attachment. For example, such charging may be performed via connectors built into the robot that send signals and power to both the interchangeable attachments and the robot&#39;s main computer system. In some embodiments, charging may occur without the robot retaining any interchangeable attachment.   16. It will be appreciated that the interchangeable attachment may be tracked by the robot using shape/color or design. Such tracking may be utilized to align to the robot for unloading and loading the interchangeable attachment.   

     In some embodiments, movement of the robot  100  may occur using all of the wheels  8  and  11 - 12 . In some embodiments, all, none, or only a subset of the wheels  8  and  11 - 12  are rotatable. 
     In some embodiments, the robot  100  may balance and move on two of its wheels (e.g., the wheels  8 ), while the front end  120  of the robot  100  is off the ground. It will be appreciated that the robot  100  may include one or more gyroscopes connected to the main body  1 . The gyroscopes may aid in keeping the robot  100  balanced once the robot  100  is positioned on two wheels. 
     The robot  100  may position itself on two wheels using various procedures. As an example, one of the interchangeable attachments may lift up the wheels  11 ,  12 , and the wheels  8  may push the wheels  11 ,  12  against a surface (e.g., a wall) so that they roll up the surface, until the robot  100  reaches an orientation where it is balanced on the wheels  8 . As another example, the wheels  11 ,  12  may be lifted (e.g., by an interchangeable attachment) and the robot  100  may accelerate sufficiently fast in the direction of the wheels  11 ,  12  such that those wheels are lifted higher, to a level where the robot  100  is balanced on the wheels  8 . 
     It will be appreciated by those skilled in the art that various omissions, additions and modifications can be made to the processes and structures described above without departing from the scope of the invention. For example, it will be appreciated that the robot  100  has been shown without any side panels or other housing around the functional illustrated components. In some embodiments, a housing or shell may be provided around the illustrated components e.g., to protect these functional components from collisions of external objects, weather, or other external phenomena that may damage these functional components. In addition, the housing may maintain a consistent external appearance and size/shape to the robot, irrespective of the sizes of the interchangeable attachments or the number of retained attachments. This may provide aesthetic benefits and/or allow a consistent interface with other devices external to the robot (e.g., a base station) irrespective of modifications to the internal components or interchangeable attachments. In addition, while various components have been illustrated and discussed as being placed at different locations, it will be appreciated that the relative locations of the various compliments may be varied while still maintaining the functionality disclosed herein. It is contemplated also that various combinations or sub-combinations of the specific features and aspects of the embodiments may be made and still fall within the scope of the description. Various features and aspects of the disclosed embodiments can be combined with, or substituted for, one another in order. All such modifications and changes are intended to fall within the scope of the invention, as defined by the appended claims.