Patent Publication Number: US-10331233-B2

Title: Camera and sensor controls for remotely operated vehicles and virtual environments

Description:
This application is a continuation-in-part of U.S. application Ser. No. 16/114,190 filed Aug. 27, 2018, which is a continuation-in-part of U.S. application Ser. No. 15/964,064, filed Apr. 26, 2018, which is a continuation-in-part of U.S. application Ser. No. 15/796,744 filed Oct. 27, 2017, which claims the benefit of U.S. provisional application No. 62/413,685 filed Oct. 27, 2016. The entirety of each of these applications is incorporated herein by reference for all purposes. 
    
    
     FIELD OF THE INVENTION 
     The present disclosure relates to controllers through which a person commands movement of a remote target augmented with a camera and other sensors, such as camera-carrying aerial drones and remotely operated underwater vehicles. 
     BACKGROUND OF THE INVENTION 
     Input devices or controllers, such as, joysticks, control columns, computer mice, cyclic sticks, foot pedals generate control inputs for a real or virtual target by sensing movement of one or more control members by a person that is commanding or controlling movement and operation of a target. These types of controllers have been used to control inputs for parameters such as to control pitch, yaw, and roll of the target, as well as navigational parameters such as translation (e.g., x-, y-, and z-axis movement) in a three-dimensional (3D) space, velocity, acceleration, and/or a variety of other command parameters. Examples of physical targets whose movement can be controlled remotely include aircraft such as aerial drones, submersible vehicles, robotic arms, industrial cranes and spacecraft. Examples of virtual targets whose movement can be controlled remotely include virtual and augmented reality simulations, computer aided design of 3-D objects and a wide range of computer games. 
     Typical drone, ROV and gaming controllers have two joy sticks mounted to a hand-held base for generating inputs for commanding movement and operation of a remote vehicle, as well as other inputs or controls for controlling operation of a camera on the remote vehicle. 
     SUMMARY 
     The present disclosure relates to improvements to controllers that are used by an operator to control movements of remote vehicles like aerial drones or other unmanned aircraft and spacecraft, submersible vessels, robotic arms, industrial cranes and similar targets that are being controlled remotely, and that have a steerable imaging sensor or other type of steerable sensor on a motorized mount that allow for a least tilting the sensor&#39;s orientation relative to the frame of reference of the remote target. 
     One aspect of the disclosure relates to orientation and positioning a mechanical input device on a controller for steering a sensor mounted on the target. Typical controllers for drones and other unmanned aerial vehicles of the type that are held by an operator have an off-axis rotary wheel that the operator turns to generate control inputs that tilt a video camera or other imagining sensor mounted on the drone. The rotary wheel is typically placed and oriented on the controller so that, if the operator&#39;s frame of reference is the drone&#39;s frame of reference, the wheel is rotated in plane that is orthogonal to the plane in which the camera tilts. It is common to forget which direction moves the camera up and which direction moves it down while operating such a controller. It is therefore relatively difficult to obtain imagery with conventional drone controllers owing to their non-intuitive input interfaces as well as the difficulty in readjusting movement rates while actively flying and acquiring imagery. The mechanical input device is oriented and positioned on the controller so that displacement of the input device corresponds to the movement of the sensor relative to the target when the controller is held in its normal operating position. In one embodiment, to tilt a sensor up and down on a target, an input device on the controller for generating a command or control input to tilt the sensor is oriented on the controller so that its displacement in a vertical plane relative to the user or pilot when the controller is in its normal, operational position and operated by the user results in generating a command to the target to tilt the sensor in the direction in which it the input device is displaced. 
     Such a controller can be adapted for controlling virtual environments, including movement of a view angle or point of view (POV) within a computer gaming or 3-D computer aided design (CAD) environment, as well as in virtual and augmented reality simulations. In one example, displacement of the input device results in a secondary control system moving a POV or simulated camera view relative to an asset moving within a virtual environment under the control of an operator in a manner that corresponds to the direction of movement of the input device by the user. Non-limiting examples of virtual environments include computer games, 3-D CAD, and virtual/augmented/mixed reality simulations. 
     A different aspect of the disclosure enables camera settings and speed adjustments for tilt and/or pan to be more easily adjusted “on the fly.” Typical commercial drone controllers, for example, require the use of an application running on a computer (laptop, tablet, smartphone or similar device) to adjust camera and camera control settings. These settings are often buried deep within a series of nested menus, which tend to discourage their use, especially by those who are not expert videographers. Most drones have a relatively short battery life, and since difficult-to-access camera controls often involve stopping a flight so that the adjustments can be made, the amount of filming on any given flight can be quite limited. 
     In one representative embodiment, a rotary wheel or other input device on a base of controller allows toggling between functions to allow the camera or other sensor parameters to be adjusted, for example responsiveness of tilt and/or pan, shutter speed, exposure compensation, zoom and other functions that are otherwise typically only made available using nested menus in an interface to a software program associated with the controller. 
     Additional aspects, advantages, features and embodiments are described below in conjunction with the accompanying drawings. All patents, patent applications, articles, other publications, documents and things referenced herein are hereby incorporated herein by this reference in their entirety for all purposes. To the extent of any inconsistency or conflict in the definition or use of terms between any of the incorporated publications, documents or things and the present application, those of the present application prevail. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1A  is a rear perspective view of an exemplary hand controller capable of displaying target situational awareness information. 
         FIG. 1B  is a front view of the hand controller of  FIG. 1A . 
         FIG. 1C  is a left side view of the hand controller of  FIG. 1A . 
         FIG. 1D  is a right side view of the hand controller of  FIG. 1A . 
         FIG. 1E  is a bottom, front right perspective view of the hand controller of  FIG. 1A . 
         FIG. 2A  is a perspective view of a two-axis gimbal. 
         FIG. 2B  is a cross-sectional view of the two-axis gimbal of  FIG. 2A  taken along section lines  2 B- 2 B. 
     
    
    
     DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS 
     For promoting an understanding of the principles of the invention that is claimed below, reference will now be made to the embodiments and examples illustrated in the appended drawings. By describing specific embodiments and examples, no limitation of the scope of the claimed subject matter, beyond the literal terms set out in the claims, is intended unless a definition for the terms is expressly given. Alterations and further modifications to the described embodiments and examples are possible while making use of the claimed subject matter, and therefore are contemplated as being within the scope of the subject matter that is claimed. 
     In the drawings and description that follows, the drawings are not necessarily to scale. Certain features of the invention may be shown in schematic form. Details or presence of conventional or previously described elements may not be shown in a figure in the interest of clarity and conciseness. 
     The present disclosure describes several embodiments of a control system or controller that allows a user to command using a single hand movement of a control target or point of reference (POR). The embodiments are representative, non-limiting examples of controllers having one or more control members that, when displaced by the user&#39;s hand or digits, generate a set of signals in each degree of freedom (DOF) of movement in which it is displaced. Each of these signals are then used to generate control inputs that are transmitted to a target control system. The controller maps the sensor signals to predetermined control inputs. The mapping can be, in one embodiment, changed or programmed so that the signal from any degree of freedom being commanded with the controller can be mapped to any control input for the target. Fewer than all of the degrees of freedom of the one or more controllers can be used if not required for the application; and one or more of the degrees of freedom of movement of the one or more controllers can be locked against movement, either temporarily or permanently, if not required for an application for which the controller is being used. 
     The control member may be mounted to a base or platform held or worn by the user, mounted on a tripod, or mounted on some other structure that acts as a frame of reference for measuring displacement of the first control member. The controller further includes signal conditioning circuits for interfacing sensors for measuring displacement of the control members, a processor for running software programmed processes, such as those described herein, a battery or other source for power, interfaces for other hardware, and transmitters and receivers for wireless communication. 
     A mobile controller that is carried in one hand, with one or more control members displaced by the other hand, provides a consistent, known reference frame (stabilized by the non-dominant hand) even while moving, e.g., walking, skiing, running, driving. For certain types of applications, for example inspection, security and cinematographic drone missions, a control member may be mounted on a platform that can be held or otherwise stabilized by the user&#39;s other hand. The platform may include secondary controls and, if desired, a display unit. In one example, all 6-DOF inputs of a controller having first control member with 3-DOF of movement and a second control member mounted to it with an additional 3-DOF of movement, can be reacted through the platform. With such an arrangement, this example of a control system facilitates movement through the air like a fighter pilot with intuitive (non-deliberate cognitive) inputs. 
       FIGS. 1A-1E  depict a non-limiting example of a controller  110  that is configured for commanding an aerial drone, such as a quadcopter, though it can also be adapted for controlling other types of targets that move in multiple degrees of freedom. Controller  110  has a first control member  112 , a joystick-like structure with three independent degrees of movement that is intended to be gripped by a user&#39;s hand, a second control member  116  mounted on the first control member for manipulation by a thumb or other digit on the hand of the user that is gripping the first control member, and an optional third control member, which enable a user to generate four independent control inputs for commanding movement of the drone in four degrees of freedom. A proximal end of control member  112  is pivotally connected to base  114  so that control member  112  can be independently pivoted along an x-axis and independently pivoted along a y-axis. In this example, the base is configured to be held by a user&#39;s hand. A base held by a user&#39;s hand provides a consistent, known reference frame (stabilized by the non-dominant hand) even while moving, e.g., walking, skiing, running, driving, can be used for inspection, security and cinematographic drone missions. 
     Installed or mounted on the base are additional input devices that are not used to command movement or orientation of the target, but other systems associated with the target. These input devices each comprise a control member that can be pressed, rotated, deflected or shifted by a finger of a person in one or two degrees of freedom to operate the controller and to issue additional control inputs to the drone and its various systems. The input devices include several buttons, dials, knobs, wheels and switches with one or two degrees of freedom. To achieve two degrees of freedom, a dial, knob or wheel, for example, can be depressed in addition to rotated. For example, flight sensitivity knob  130  sets the level of the sensitivity level of the movements of the hand controller movements by the user in order to increase or decrease the responsiveness of the drone to the movements. Programable button  140  that can be programed by the operator to perform a function desired by the operator when depressed. A controller on/off switch or button  142  is used to turn to the power to the hand controller on or off. Arm drone button  144  enables the drone. Return home button  146  causes the controller to transmit a command to the drone that causes the drone to return to a predesignated place autonomously. 
     The base houses signal conditioning circuits for the input devices, a processor for running software programmed processes, a battery or other source for power, interfaces for other hardware, and transmitters and receivers for wireless communication. Actuation or displacement of the input devices is sensed by circuits in the controller. In the case of input devices that are angularly displaced or rotated, the degree of angular rotation is sensed. Power indicator light  148  illuminates when the hand controller is on, and battery indicator  150  indicates the level of charge of the hand controller batteries. 
     Unmanned vehicles have a video camera for transmitting back to the remote operator. The video camera is mounted with the camera facing in a forward direction, so that when the vehicle moves forward the camera is pointing, usually, straight ahead in the direction of travel. The base includes manually-displaceable user interface elements for use by the controller to generate control inputs for a camera on the target, including a wheel  132  for changing camera settings, a paddle  134  for changing camera tilt, a button  136  for releasing a camera shutter, and button  138  for starting and stopping recording of video. 
     A rotating wheel  132  changes camera settings for the video camera or other sensor input, such as exposure or sensitivity, aperture, and resolution, or to select preset combinations of these settings. For example, the rotary wheel has a plurality of positions that allows a user to rapidly reconfigure the camera-related setting by selecting from several preconfigured settings. These parameters include the responsiveness of the platform or mount on the remote vehicle to commands to adjust (tilt and/or pan) the orientation or point of view (POV) of the camera (or sensor), or in the case of virtual object whose motion in a virtual environment is being commanded, the virtual POV of the virtual object, as well as the ability to toggle to other common camera features without diving deep into an app, such as zoom, shutter speed exposure compensation. 
     A button  136  for the shutter release causes a control input to be generated and sent the drone to take a photograph or series of photographs. Button  138  starts and stops recording of the video sent by the video camera. The video can be shown on a display (not shown) that is attached to mount  152  and arm  154 . In on embodiment, a smartphone is used for displaying video in addition to setting up and modifying settings for the controller, as well as performing additional processes for the controller. The display or smartphone is connected by wire or wirelessly to the controller. In other embodiments, other display devices such as a tablet, computer, monitor, or standalone display could be substituted. 
     The base is of a size and shape that enables an operator or user to hold the base in one hand and operate the control members with the other hand. The placement of control members  116  and  118  onto the end of control member  112  allows an operator to operate control member  112  with the palm and two or three fingers of one hand while at the same time operating control member  116  and control member  118  with the thumb and the forefinger, respectively, of the same hand being used to operate control member  112 . The operator&#39;s other hand  133 , can be placed underneath the hand controller to support the hand controller and also to operate one or more additional inputs for controlling the camera with the fingers of the hand that is supporting the hand controller. This allows the operator to keep one hand on the control member  112  at all times during controlled repositioning of the target to generate control inputs in up to three degrees of freedom, while also being able to manipulate control member  116  (and, optionally  118 ) to generate control inputs for the target in additional degrees of freedom, hold the base, and operate a camera on the remote. 
     Aerial drones often have video cameras that offer tilting but not panning the camera with respect to the drone. Adjustment of the view of the camera from side to side is typically accomplished by rotating the facing of the drone. The drone is, in other words, rotated to pan the camera. Therefore, this example includes paddle  134  for controlling camera tilt that need only be deflectable in one degree of freedom. Displacement of the paddle  134  by deflecting it upwardly or downwardly causes generation of a command input to the remote target&#39;s control system that actuates a motor for a single axis camera tilt mechanism, with which a video camera is mounted to the drone. 
     The paddle  134  for commanding tilt is, in this example, located on the front of base  114  where an index or other finger of a hand holding the base can reach it. When an operator uses his or her hand to support base  114 , the operator can reach and operate camera rotary control  132  with the thumb or forefinger of the same hand that is supporting base  114 . The base is shaped to allow either right or left-handed use. Camera controls  136  and  138  for taking a photograph and starting and stopping video recording are located on the side of the base where they can also be reached by the thumb or other fingers of the hand holding the base. 
     Deflection of paddle  134  within a plane that is vertical with respect to the user&#39;s frame of reference when holding and operating the controller causes the controller to generate a control output for changing camera tilt. Deflecting downwardly causes generation and transmission of a control output to the target&#39;s control system to tilt the camera downwardly; deflecting it upwardly causes the controller to transmit a control output that results in the video camera being tilted upward. 
     In this example, the paddle  134  comprises part of an input device that pivots about a single axis. The paddle is a control member that a user can easily find by feel and deflect upwardly or downwardly. Deflection of the control pivots a mount or support, the angular displacement of which is sensed by the controller. The controller responds by generating a camera tilt rate command and communicating it on a signal transmitted to the target, the command indicating the direction and amount or degree of deflection. Alternatively, the controller issues an absolute command, meaning that the position of the input device corresponds to the position of the camera, sensor or POV. 
     The magnitude of the deflection upward or downward of the input device  134  determines the rate of adjustment that is communicated to the target&#39;s camera (or other sensor) control system, and the duration of the deflection determines the duration of the adjustment. In response to receiving a tilt rate command, a camera control system on the target operates a motor that pivots or moves the camera mount to tilt the camera in a direction, at a rate, and for a duration corresponding to the direction, magnitude and duration of displacement from the null position of the input device  134 . 
     In one embodiment, the paddle  134  is biased toward a center position in its range of motion, which corresponds to a “null” or zero input position. This allows it to be deflected by a user&#39;s finger upwardly or downwardly and then released to return it to null or no-input by means of a centering spring force. This is a natural, intuitive, and comfortable movement for the user since upward motion corresponds to an upward adjustment in camera tilt and downward motion corresponds to downward adjustment of camera tilt. In an alternative embodiment, when generating an absolute command, the centering force may be omitted to allow the input device to remain in the position to which it is moved so that the camera/sensor/POV will also remain at that position. 
     In alternate embodiments, other shapes or configurations of control members could be substituted. For example, it could take the form of a toggle, wheel, or joystick that is mounted so that it is free to move in a vertical plane (with respect to a user when operating the controller in its intended manner), pivoting or rotating about an axis that is horizontal so that, during operations, the cameral tilt input is vertical and thus intuitive for the pilot. 
     In one embodiment the input device comprising paddle  134  is, as previously mentioned, biased to the null position using a centering spring or other mechanism to generate a force. The magnitude of the force may vary with the magnitude of the deflection, thus providing a force-feedback mechanism. Passive mechanical, vibration haptic or active mechanical feedback to the user may also be incorporated. For example, haptic or tactile feedback may, optionally, be generated for the user when the input device leaves and/or returns to the null position. 
     Although the input device for commanding camera tilt need only be displaceable in one degree of freedom, it may also be implemented using a multi-axis mounting that supports pivoting of a control member in one degree of freedom that lies with a vertical plane relative to the user&#39;s frame of reference when the base is in its normal operating position with respect to the user, but with its other degrees of freedom locked or inactive. 
     If the target includes a camera mount with both tilt and pan capability, the input interface for cameral control input for the controller may be modified for displacement in two degrees of freedom. The input device would be capable of detecting the degree of angular displacement in each of two degrees of freedom independently, and the controller would respond by generating a control input for commanding tilt and a separate control input for commanding pan. In this embodiment (not shown), the input device is mounted on the base so that one degree of freedom lies within a plane that is oriented vertically with respect to the user&#39;s frame of reference when operating the controller, and a second degree of freedom is within a plane that is oriented horizontally with respect to the user&#39;s frame of reference. Deflection up and down of a control member, such as joystick, causes the input to generate a rate adjustment command for the camera mount to tilt the camera with respect to the target. Deflection from side-to-side causes the controller to generate rate adjustment command for the camera mount to pan the camera with respect to the target. Examples of control members for a two degree of freedom input device include not only a joystick, but also a paddle, button or other structure that is constrained to move two degrees of freedom. The two degree of freedom input device would, in one embodiment, be biased to return to a null or zero input position for both degrees of freedom using springs or similar mechanisms. In another embodiment, where absolute command of the camera pan and/or tilt is desired, the input device can be moved to the desired camera position and released without it returning to the null position tilt and/or pan. 
     In still other embodiments, a camera pan control may be added to the base. Except for its orientation, different embodiments of the pan control operate in the same way as the different embodiments of the tilt control described above operate. However, it could, optionally, look and/or feel differently so that it can be easily distinguished by touch and/or sight. The pan control is oriented so that deflection of the pan control is side-to-side or horizontal, and thus is natural, intuitive, and comfortable correspond to the pan of the camera. Thus, for example, the pan tilt control may be a paddle-type of input device like input device  134  for camera tilt, except instead of being configured so that control member is deflected up and down, it is oriented to be deflected from side to side to correspond with the side-to-side panning movement of the camera. However, it may be modified to generate absolute commands for positioning the pan of the sensor or POV, without the biasing force to recentering it to the null position upon release. 
     When a pilot establishes an intent to tilt the camera to track an object of interest, the pilot inputs a tilt command by deflecting the paddle  134  and then releasing it. The controller, in response, generates control input that is transmitted to the remote vehicle&#39;s onboard control system over a wireless communications channel. The control input comprises a rate command sent to the remote vehicle or target. The remote vehicle&#39;s onboard control system then causes the camera mount to tilt the camera at a rate and for duration that is proportionate to the magnitude and duration of the deflection of the paddle. If a control input is available for panning, the same process can be used with an input device that deflects from side-to-side, with the control input being issued to command the remote vehicle&#39;s onboard system to pan the camera. 
     The examples described above for controlling camera tilt and pan may also be used to steer other types of sensors—a still or video camera being one type of image sensor—that can be attached to a motor-controlled mount on the target and rotated in one or two degrees of freedom to tilt or pan the sensor relative to the frame of reference of the target. 
     Input devices for controllers of the type described above for generating control inputs to steer cameras or sensors can be characterized as being comprised of a control member that is supported by a mount that allows for the control member to be manually deflectable in one or two degrees of freedom, with the degree of deflection preferably measurable by one or more sensors in the mounting. Examples of mounts that can be used to support the control members include a single or multi-axis gimbal and a ball and socket joints. Examples of sensors that can be used to detect and, optionally, measure displacement of manually displaceable interface elements and control members include switches, inertial measurement units, potentiometers, optical encoders, Hall effect sensors, and the like. A processor within the controller responds to signals generated by the sensors and generates control inputs that are transmitted by radio frequency, optical or wired (electrical or optical) signals or a combination to the target. 
     Mechanisms that support measuring of angular displacement of control members to indicate displacement, such as gimbals, may optionally include springs for centering the control member and generating force feedback. Couplings or linkages that connect the joystick to a gimbal support, for example, could, in some embodiments, be made adjustable or adaptable to accommodate joysticks of different sizes for different sized users. 
       FIGS. 2A, 2B  illustrate schematically a representative example of an implementation of a two-axis gimbal mount  200  that can be used as part of an input device for generating control inputs to command a camera or sensor steering system. The two-axis gimbal mount can be used to support simultaneous angular displacement and measurement of the angular displacement in two degrees of freedom but may be adapted by locking one degree of freedom to be used to support a control member for displacement in a single degree of freedom. The gimbal can be mounted in a base, such as base  114  (see  FIGS. 1A-E ). Its post  202  couples the gimbal mount to a control member. The control member pivots the post about two orthogonal axes that intersect at the center of the gimbal. One axis remains fixed relative to the base and the other rotates about the fixed axis. Two-axis gimbal mount  200  is a representative example of a two-axis gimbal that has been adapted to generate to haptic feedback upon the control member leaving and reentering a predefined null position for each of these two axes of rotation. 
     Furthermore, in an alternate embodiment in which the gimbal can be locked or blocked from rotation about one axis to allow only for rotation about one axis, the detents for generating force feedback for rotation about the locked or blocked axis could be omitted. 
     The gimbal is comprised of two members: one that remains fixed with respect to base or enclosure and second member that is constrained by the first member to rotate about a single axis or to rotate about each of two orthogonal axes, and to otherwise restrict relative rotation of the first and second members around any other axis. A post is coupled to the second member to pivot about each of the two orthogonal axes. If the second member is restricted to rotate only about one of the two orthogonal axes, the post is coupled with the second member so that it is can pivot about the second axis without rotating the second member. In this particular implementation, which is intended to be representative, a ball  206  is mounted within a socket  208 . An extension  212  of the post fits within a complementary opening formed in the ball  206  so that angular displacement or pivoting of the post  202  also rotates the ball. In this example, the ball is retained within the socket so that it can freely rotate within the socket in two degrees of freedom, about each of two axes that are mutually orthogonal to each other, with one of the two axes remaining fixed relative to a base  209  of the gimbal mount. It may, optionally, be permitted to rotate about a third mutually orthogonal axis extending through the post. The base  209  is representative of a structure for mounting the gimbal, against which a control member may react. 
     A cap  210  that is connected with the post extends over a spherically-shaped outer surface of the socket  208  and has a complementary, spherical inner surface. Pivoting of the post moves the cap relative to the socket. 
     Although an inner surface of socket  208  can complement and support rotation of the ball  206 , the ball  206  can, in alternative embodiments, be supported for rotation about one or both mutually orthogonal axes of rotation in other ways and by other means, including by one or more shafts or axles that support rotation of the ball relative to the socket. In such an alternative embodiment, the ball  206  and inside surfaces of the socket  208  need not be spherical or complementary. 
     This structure could be modified, or other structures could be substituted for the ball and socket, for a two-axis gimbal for supporting pivoting of the post  202  in two degrees of freedom. For example, the complementary opening in the ball in which extension  212  fits could be formed as a slot that allows the post to pivot about a fulcrum located within the slot that is aligned with a first one of the two orthogonal axes of rotation. Thus, it could pivot without rotating the ball. Rotation of the ball is constrained to allow for rotation only about a second one of the two orthogonal axis of rotation, which would then have a fixed position relative to base  209 . Deflecting the post about the second axis of rotation would case the ball to rotate about the second axis. 
     To detect angular deflection of the post about each of the two axes of rotation, one or more magnets  216  are placed at the bottom of ball  206  (when in the null position.) This allows a printed circuit board (PCB)  218  with at least one Hall effect sensor  220  to be positioned closely to detect and measure angular displacement of the ball in up to two rotational degrees of freedom and thereby generate signals representative of the displacement. The Hall effect sensor is preferably a three-dimensional Hall effect sensor, in which case one is sufficient. One advantage to this arrangement is that the springs and the joystick are positioned higher up, keeping the bottom of the gimbal available for placement of a Hall effect sensor. Other types of sensors could be, in other embodiments, substituted for the Hall effect sensor and magnet, including optical encoders, potentiometers, and other types of sensors or detectors for detecting rotation of the gimbal about each of the axes. 
     The same gimbal support could be adapted to be used as part of an input device that moves only in one degree of freedom by locking one of the two axes temporarily, dynamically (based on the capabilities of the particular target being controlled or a mode of operation of the target or the camera), or permanently. Locking can be done physically by incorporating a structural feature that interferes with pivoting about one axis of rotation. For example, the socket  208  and ball  206  could be configured to lock the ball and socket in one axis of rotation, thus allowing relative rotation about only one of the two axes of rotation. Examples of such a lock include a pin that can be placed or selectively slid into and out of an interfering position or a latch that can be pivoted into and out of an interfering position, either selectively or permanently. Alternatively, at the time of making the gimbal, a component that allows for movement in one degree of freedom can be substituted with one that does not. In other embodiments the lock can be implemented with a magnet or electromagnet that provides sufficient resistance. 
     The gimbal mount  200  comprises a means for generating haptic feedback that is mechanical and comprises at least one detent for each degree of freedom. In this example, gimbal  200  comprises at least two detents  204  that cooperate with surface features on ball  206  located at the null position for one of the two degrees of freedom. The pair of detents and surface features interact to generate a mechanical force that can be felt when the post enters or leaves a null position for one axis of rotation. The other pair of detents are positioned orthogonally to the pair of detents  204  that can be seen. The detents generate a mechanical force feedback when entering and leaving a null or zero position when rotating about the other axis of rotation. A single detent could be used for each direction of rotation, but a pair provides balance. 
     The detents have a rounded or spherical engaging surface that is biased outwardly but displaceable inwardly once the biasing force is overcome. In this example, the detents are in the form of balls that are biased by springs  205 , but other types of detents could be substituted. Only a pair of detents can be seen in the figures. The detents have one or more biasing springs mounted in a sleeve with a lip that retains the ball but allows it to extend. 
     A cap  210  is connected with the post  202  and comprises a cup-shaped member with a spherically shaped inner surface that complements a spherically shaped outer surface of socket  208 . It is capable of pivoting in two degrees of freedom that correspond to the degrees of freedom in which the post  202  may pivot, the spherical inner surface rotating about the point where the two mutually orthogonal axes intersect when the post is pivoted. 
     In this example, all detents  204  engage the groove  214  when the ball is rotated to the null position in both directions of rotation. Instead of continuous groove  214 , a small depression or dimple for each detent could be placed at the null position for each detent. The detents are all located in the same plane, which is normal to a central axis of the post  202 . They are equally spaced at 90-degree intervals around the intersection of the central axis and the plane. When the post  202  is in a null position, one opposing pairs of detents is positioned so that the detents in that pair are colinear along a line that is parallel to one of the two orthogonal axes of rotation, and the other opposing pair of detents  204  are colinear along a line that is parallel to the other of the two orthogonal axes of rotation. 
     Instead of having the interfering surface features—the dimples or groove—on ball  206 , an alternative embodiment may use the inner surface of the cap  210  and the outside of the socket  208  to support the detents and interfering surface features that interact to generate a haptic feedback when the post is moved from a predefined null position in each of the degrees of freedom. 
     A detent engaging and disengaging from the groove or other depression provides mechanical tactile feedback to a user at null positions in two axes of rotation. While the two-axis gimble mount is in the null position, each detent is aligned with a corresponding dimple or other type of recess, indentation, depression, groove, or surface feature. The surface feature is shaped to allow the detent to extend under its biasing force and thus interfere with the relative movement of the cap and socket. When a sufficient torque is applied by the post  202  to overcome the force created by the interference of the detent and the surface feature, the biasing force is overcome, and the detent is pushed inward to allow the relative movement. It remains pushed inward until it aligns again with a depression in the surface that allows it to extend. A deflection of the post  202  around each one of the axes of rotation will thus be met with at least some resistance, and the resistance will be felt as a haptic feedback to a user moving the post by moving a control member. Similarly, when the post  202  pivots back to a null position in one of the degrees of freedom the detents for that degree of freedom will extend into the recess. A user will feel the actuation force to relax subtly as the detent passes by one side of the wall of the recess that forms the dimple and extends into the dimple. The user may also feel the detent hitting the wall of the dimple on the other side of the dimple, reinforcing the user&#39;s sense that they&#39;re back at zero. The drop off in resistance is followed by a ramp up of resistance is the haptic cue that communicates to the user that the null position for that degree of freedom has been reached without having to look or to find the null position, such as by releasing the control member and allowing it to return under a spring force to the null position. This can be of advantage in many applications, particularly those in which the user is mobile. 
     Referring back to  FIGS. 1A-E , controller  110  will generate control inputs to the target in four degrees of freedom but can be adapted or configured to generate control in up to any number of degrees of freedom up to six degrees of freedom. Controller  110  has a first control member  112  with three independent degrees of movement that is intended to be gripped by a user&#39;s hand. A proximate end of control member  112  is pivotally connected to base  114  so that control member  112  can be independently pivoted along an x-axis and independently pivoted along a y-axis. Pivoting control member  112  along the x-axis tilts the moves the distal end of control member  112  side to side, relative to base  114 . Pivoting control member  112  along the y-axis pivots the distal end of control member  112  forward and backward relative to base  114 . Control member  112  could be made to pivot along only the x-axis or y-axis or may simultaneously pivot around both the x and y axes. The pivotal connection between control member  112  and base  114  may be made by a number of pivoting type connections, such as a gimble or a ball and socket. The controller is also movable in a third degree of freedom by twisting it around a z-axis that is orthogonal to the x and y axes. The first control member thus displaceable in three degrees of freedom, each of which can be used to generate three, independent control inputs for commanding three degrees of freedom of movement of the target. 
     A fourth degree of movement and of freedom is provided by control member  116  located on a distal end of control member  112 . Control member  116  in this example is a thumb displaceable along the z-axis by operator&#39;s thumb is placed onto the base of control member  116  and retained by thumb catch  122 . Thumb catch  122  is adjustable to accommodate the size of a particular user&#39;s thumb so that movement of the user&#39;s thumb will be translated into movement of control member  116 . Control member  118  is a trigger style control member that may be operated by a user&#39;s index finger on the same hand that is gripping the first control member. The control member  116  and control member  118  are linked to move in opposition to one another generate a fourth control input. An operator uses the operator&#39;s thumb and control member  116  to move control member  116  downward by pressing down with the user&#39;s thumb. A user may move control member upward by raising the user&#39;s thumb which is retained by thumb catch  122 , which is connected to control member  116 . An operator may also move control member  116  upward by squeezing control member  118 . The cooperation between control member  116  and control member  118  may be accomplished in any number of ways, including using a direct, mechanical linkage or by actuators. In alternative embodiments, control member  118  can be omitted or not linked to control member  118 , in which case it can be used for other purposes. 
     This controller could be adapted in alternative embodiments to allow for different degrees of freedom of displacement for each of its first and second control members. For example, the second control member can be allowed to be displaced by a user&#39;s thumb or index finger in two additional degrees of freedom so that the controller can be displaced in six degrees of freedom with single hand and thus generate six independent control inputs. In alternate embodiments, displacement of the third control member could be used to generate another control input and not be linked to the second control member. Many control scenarios may benefit from being able to provide rotational and translational movement using a single hand, even if fewer than all control outputs for all six degrees of freedom are required. The unused degrees of freedom could be locked out temporarily or permanently. 
     Hand controller  110  also comprises display  124  on an extension  120  at the top of the controller. The extension allows the display to be better oriented toward the operator, so the operator may operate the hand controller and observe display  124  at the same time. It also allows for accommodation of second control member  116 . Display  124  is used to provide situational awareness information to the operator regarding the device being controlled by the hand controller. In this example, the display includes a direction-to-target indicator  126  is comprised of a series of display elements arranged in a half circular pattern that corresponds to the 180-degree arc directly in front of the hand controller. Direction-to-target indicator  126  indicates the direction of the drone from the hand controller by illuminating the light that corresponds to the relative direction of the drone from the hand controller. The display also comprised of target orientation indicator  128 . Target orientation indicator  128  indicates the orientation or heading of the target relative to the hand controller. A mobile, two-handed controller system like the one described above is capable of providing a consistent, known reference frame (stabilized by the non-dominant hand) even while moving, e.g., walking, skiing, running, driving. For certain types of applications, for example inspection, security and cinematographic drone missions, a hand controller may be mounted on a platform that can be held or otherwise stabilized by the user&#39;s other hand. The platform may include secondary controls and, if desired, a display unit. In one example, all 6-DoF inputs of a controller, having first control member with 3-DOF of movement and a second control member mounted to it with an additional 3-DOF of movement, can be reacted through the platform. With such an arrangement, this example of a control system facilitates movement through the air like a fighter pilot with intuitive (non-deliberate cognitive) inputs. 
     U.S. patent application Ser. Nos. 13/797,184, 15/071,624, 15/964,064 and 16/114,190, which are incorporated herein by reference for all purposes, disclose several examples of controllers that allow a single hand of an operator to generate control inputs in more than three, and up to six, degrees of freedom (6-DoF), simultaneously and independently. Various aspects of the single-handed controllers described in these applications better enable users, whether they are in motion or at rest (such as computer augmented or virtual reality gamers, pilots, hikers, skiers, security/SAR personnel, war-fighters, and others, for example) to control an asset or target in physical and/or virtual three-dimensional space, by generating control inputs while also limiting cross-coupling (unintended motions). A controller with these features can be used to allow the controller to decouple translation (movement in physical space, or X, Y and Z directions) from attitude adjustments (reorientation in pitch, yaw and roll) in the control requirements of computer aided design, drone flight, various types of computer games, virtual and augmented reality and other virtual and physical tasks where precise movement through space is required such as fixed wing and rotary wing flight, aerial refueling, surgical robotics, terrestrial and marine robotic control, and many others. The aspects described above can be adapted for use with the embodiment described in the referenced applications. 
     The base may, optionally, incorporate additional manually displaceable user interface elements such as keys, buttons, dials, touchpads, trackpads, track balls. By locating the first control member midline to the controller off-axis moments are reduced and making it symmetric allows for use with either hand. However, the base could be made asymmetric. It could also be modified to allow reconfiguration for either hand with a quick disconnect for the joystick and two mounting points. In other embodiments, rather than having a user hold the base, the base could be configured to be stabilized by mounting the base to the user&#39;s body. Example of mounting points for a base on a user&#39;s body include a chest mount, a belt, and an article of clothing. 
     Variations may be made in the above without departing from the scope of the invention. While specific embodiments have been shown and described, modifications can be made by one skilled in the art without departing from the spirit or teaching of this invention. The embodiments as described are exemplary only and are not limiting. Many variations and modifications are possible and are within the scope of the invention. Furthermore, one or more elements of the exemplary embodiments may be omitted, combined with, or substituted for, in whole or in part, with one or more elements of one or more of the other exemplary embodiments. Accordingly, the scope of protection is not limited to the embodiments described, but is only limited by the claims that follow, the scope of which shall include all equivalents of the subject matter of the claims.