JP6351697B2 - Support mechanism and system - Google Patents

Description

  The present invention relates to a technology of a support mechanism.

  It is known to support a camera or the like using a spherical actuator. For example, Patent Document 1 proposes a spherical actuator that attaches one camera to a base of a movable member that rotates along the surface of a sphere, and rotates the sphere around the movable member.

JP 2009-225591 A

  However, in this spherical actuator, the center of gravity of the movable member is greatly biased toward the pedestal side where the camera is located. For this reason, the center of gravity of the spherical actuator largely fluctuates with the rotation of the movable member.

  The objective of this invention is providing the technique regarding the support mechanism which suppresses the gravity center fluctuation | variation accompanying a drive.

  In one aspect, the support mechanism includes a first member having a curved surface, a plurality of actuators moving on the surface, a second member connected to the plurality of actuators and rotating around the first member, The second member can support at least two of the plurality of supported bodies at positions opposite to each other across the first member.

  In this aspect, the plurality of actuators move on the curved surface of the first member. A second member connected to the plurality of actuators also moves along this surface and rotates around the first member. Since the second member can support a plurality of supported bodies, the plurality of supported bodies supported by the second member also rotate around the first member.

  Here, at least two of the supported bodies supported by the second member are positioned on opposite sides of the first member. These supported bodies apply forces (rotational moments) in opposite directions to the second member due to their own weight.

  Accordingly, the center of gravity of the second member is higher than that of the second member as compared with the case where only one supported body is supported by the second member or when the plurality of supported bodies are supported only on the same side. Approach the center of rotation. Therefore, the center-of-gravity variation of the support mechanism accompanying the drive of the second member (the rotation of the second member around the first member and the plurality of supported bodies) can be suppressed.

  The second member may have a ring surrounding the first member.

  The plurality of supported bodies may be supported at equal intervals in the circumferential direction of the ring.

  The plurality of supported bodies may include supported bodies having different weights.

  The plurality of supported bodies may include supported bodies having the same weight.

  The second member may be rotatable about the yaw axis of the first member, and the center of gravity of the second member that supports the plurality of supported bodies may be located on the yaw axis.

  In this aspect, since the center of gravity of the second member is balanced with respect to the yaw axis while supporting a plurality of supported bodies, the second member is maintained in a horizontal posture (a posture parallel to the horizontal plane (ground)). The torque required for this can be reduced. In addition, the center of gravity of the support mechanism can be prevented from changing as the second member rotates about the yaw axis.

  The plurality of supported bodies may include different types of supported bodies.

  The plurality of supported bodies may include the same type of supported bodies.

  At least one of the plurality of supported bodies may be an omnidirectional camera or a hemispherical camera.

  At least one of the plurality of supported bodies may be a weight.

  An inertial sensor attached to at least one of the second member or the plurality of supported bodies may be provided.

  In another aspect, the support mechanism includes a first member having a curved surface, a plurality of actuators moving on the surface, a second member connected to the plurality of actuators and rotating around the first member, And an inertial sensor attached to the second member.

  In this aspect, the plurality of actuators move on the curved surface of the first member. A second member connected to the plurality of actuators also moves along this surface and rotates around the first member. Here, since the inertial sensor is attached to the second member, the movement of the second member can be detected with a simple configuration, and the posture and rotation around the first member can be controlled.

  The inertial sensor may be an angular velocity sensor or an acceleration sensor.

  Based on the inertial sensor, at least one of the position, posture (pitch angle, roll angle, yaw angle, etc.), angular velocity, and angular acceleration of the second member may be detected.

  The first member is connected to the base body, and the inertial sensor is calibrated based on a relative position between the second member and the base body or a relative position between the second member and a predetermined reference position outside the support mechanism. It may be.

  The second member may be capable of supporting one or a plurality of supported bodies.

  The attitude of at least one supported body may be controlled based on the movement of the second member detected by the inertial sensor.

  The inertial sensor may be attached to at least one supported body.

  The inertial sensor may be separated from the supported body.

  The inertial sensor may detect the movement of the second member during driving of the supported body.

  The first member may be connected to the base, and the base may further include an inertial sensor.

  The inertial sensor may detect the attitude angle of the second member relative to at least one of the pitch axis and the roll axis of the first member.

  The inertial sensor included in the base may detect the attitude angle of the second member or the base with respect to the yaw axis of the first member.

  You may make it calibrate a 2nd member with respect to a base | substrate using the attitude | position angle of a 2nd member and the attitude | position angle of a base | substrate at least.

  The plurality of actuators may move the second member based on a predetermined posture angle.

  You may make it determine the torque which a some actuator outputs based on a predetermined attitude | position angle.

  The torque may be determined using a PID controller.

  The PID controller may be provided on the second member.

  The first member may be connected to the base, and the PID controller may be provided on the base.

  The support mechanism may be connected to the moving body via a base connected to the first member, and the PID controller may be provided on the moving body.

  The PID controller determines an angular velocity based on a difference between a posture angle detected by the inertial sensor and a predetermined posture angle, and determines a torque based on a difference between the determined angular velocity and the angular velocity detected by the inertial sensor. You may do it.

  The plurality of actuators may be in contact with the surface of the first member.

  The surface of the first member may be spherical, and the plurality of actuators may be arranged at equal intervals along a great circle or a small circle on the surface.

  The first member may be fixed to the base.

  The second member may rotate around the first member at least about the roll axis, pitch axis, or yaw axis of the first member.

  The first member may be rotatably connected to the base via a motor.

  The first member or the base may be attached to the rotor of the motor.

  The rotation angle of the motor may be detected using a magnetic sensor.

  The motor may rotate the first member around the yaw axis of the first member with respect to the base.

  The second member may rotate around the first member at least about the roll axis or pitch axis of the first member.

  The second member may be further rotated about the yaw axis of the first member around the first member.

  Electric power may be supplied from an external power source to the support mechanism.

  The first member may be connected to the base body and provided with a power source.

  The support mechanism may be connected to the moving body via a base connected to the first member, and the moving body may be provided with a power source.

  The support mechanism may be connected to the moving body via a base connected to the first member.

  In one aspect, a system including the support mechanism according to any one of the above aspects and a moving body to which the support mechanism is attached may be configured.

  In one aspect, a support mechanism is provided that includes a first member having a curved surface, a plurality of actuators moving on the surface, and a second member connected to the plurality of actuators and having an inertial sensor attached thereto. A method of detecting a movement of the second member using an inertial sensor, and driving a plurality of actuators based on the detected movement of the second member to move the second member around the first member. And rotating the method.

  In this aspect, the plurality of actuators move on the curved surface of the first member. A second member connected to the plurality of actuators also moves along this surface and rotates around the first member. Here, since the inertial sensor is attached to the second member, the movement of the second member can be detected with a simple configuration, and the posture and rotation around the first member can be controlled.

  ADVANTAGE OF THE INVENTION According to this invention, the technique regarding the support mechanism which suppresses the gravity center fluctuation | variation accompanying a drive can be provided.

It is a block diagram which shows the structure of the system provided with the support mechanism. (A) is a perspective view which shows an example of a support mechanism, (B) is a schematic diagram for demonstrating arrangement | positioning of an actuator. It is a perspective view which shows an example of a support mechanism. (A) is a schematic diagram which shows an example of the support position of three to-be-supported bodies, (B) is a schematic diagram which shows an example of the support position of two to-be-supported bodies. It is a perspective view which shows an example of a support mechanism. It is a block diagram for demonstrating the calibration method of a support mechanism. It is a flowchart for demonstrating the calibration method of a support mechanism. It is a block diagram for demonstrating PID control of a support mechanism. It is a flowchart for demonstrating the control method of a support mechanism. It is a perspective view which shows an unmanned aircraft. It is a block diagram which shows the structure of the unmanned aircraft which attached the support mechanism.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The configurations described in the following embodiments are merely examples, and the present invention is not limited to the illustrated configurations. Each embodiment and its modifications can be replaced or combined as long as technically possible. In the following description, the same names are used for the same or similar configurations unless otherwise specified.

  The claims, the description, the drawings, and the abstract include matters subject to copyright protection. The copyright owner will not object to any number of copies of these documents as they appear in the JPO file or record. However, in other cases, all copyrights are reserved.

  With reference to FIG. 1, the structural example of the system provided with the support mechanism and the movable body is demonstrated. As shown in the figure, the system 1 is configured by connecting a support mechanism 100 and a movable body 101 via a base 103.

  The support mechanism 100 includes a stator 105 (first member), a frame 107 (second member), a plurality of actuators 109, and the like. The stator 105 and the plurality of actuators 109 constitute a motor assembly 111.

  The stator 105 is a sphere having a spherical surface. As a modification, the stator 105 may be another shape having a curved surface, for example, a hemisphere, a cylinder, a spheroid, or the like.

  The frame 107 is connected to a plurality of actuators 109. The frame 107 can support one or a plurality of supported bodies. The supported body is an object supported by the frame 107. For example, the supported body may be an imaging device (such as an omnidirectional camera, a hemispherical camera, or a video camera), a sensor (such as an image sensor or an audio sensor), an image output device or an audio output device (such as a television or a speaker), or a communication device. Also, a device such as a robot arm may be used. For example, the supported body may be a weight for balancing the weight of the device. For example, the frame 107 may be directly supported by fixing the supported body on the surface thereof, or may be indirectly supported through an attachment member or the like connected to the frame.

  The plurality of actuators 109 function as a rotor for the stator 105. The plurality of actuators 109 contact the stator 105 and move on the spherical surface, and rotate the frame 107 with respect to the stator 105, for example, in three axes (roll axis, pitch axis, and yaw axis).

  The plurality of actuators 109 are, for example, piezoelectric actuators. In the piezoelectric actuator, the piezoelectric element slightly vibrates when a voltage is applied. When the ultrasonic waves generated by the minute vibrations are transmitted to the spherical surface of the stator 105, the plurality of actuators 109 move along the surface of the stator 105 due to frictional force. Accordingly, the frame 107 connected to the plurality of actuators 109 also rotates with respect to the stator 105. By controlling the voltage applied to each of the plurality of actuators 109, the posture and rotation of the frame 107 with respect to the stator 105 can be controlled.

  The motor assembly 111 includes a stator 105 and a plurality of actuators 109. The motor assembly 111 is, for example, a motor that directly applies a force (for example, ultrasonic waves) to the frame 107, and rotates the frame 107 with respect to the base 103 and the movable body 101 with one or a plurality of axes. As a modification, the motor assembly 111 may be a motor that uses an electromagnetic force of a coil or a magnet as a driving force.

  The movable body 101 is, for example, a moving body. Examples of the moving body include an unmanned aerial vehicle (hereinafter referred to as “UAV”), an aircraft, other equipment that moves in the air, a vehicle that moves on the ground, a ship that moves on the water, a robot, and the like. As a modification, the movable body 101 may be a living body (human, animal), or a device supported or attached to the living body.

  The base 103 connects the support mechanism 100 and the movable body 101. The base 103 may be connected so that the support mechanism 100 and the movable body 101 do not move relative to each other. Alternatively, the base 103 may be connected so that the support mechanism 100 and the movable body 101 are relatively moved (for example, rotated by one or a plurality of axes). As a modification, the support mechanism 100 and the movable body 101 may be directly connected without using the base body 103.

  An example of a support mechanism is shown with reference to FIG. As shown in FIG. 2A, the support mechanism 200 includes a stator 201, three piezoelectric actuators 203-1, 203-2 and 203-3 (hereinafter collectively referred to as “piezoelectric actuator 203”), and a connection member. 204, a frame 209, a shaft 211, and the like.

  The support mechanism 200 is connected to the base body 213 via the shaft 211. In the figure, three axes 207-1, 207-2, and 207-3 orthogonal to each other are a yaw axis, a pitch axis, and a roll axis, respectively.

  The stator 201 is a sphere having a spherical surface, and is fixed to one end of a rod-shaped shaft 211 at one point on the surface. The shaft 211 is fixed to the base 213 at the other end.

  The piezoelectric actuator 203 is connected to the stator 201 and moves on the surface of the stator 201 (except for a portion where the shaft 211 is fixed). The piezoelectric actuator 203 is arranged along the same circumference of the stator 201, more specifically, a small sphere of the sphere constituting the stator 201 (cut when the stator 201 is cut by a plane not including the center thereof). (Circle) and are spaced apart uniformly along the circumferential direction. Here, the piezoelectric actuators 203 are disposed at a relative angle of 120 degrees with respect to the center of the stator 201.

  The size of the small circle is defined by the attitude angle α of the piezoelectric actuator 203 with respect to the plane including the pitch axis 207-2 and the roll axis 207-3, as shown in FIG. The posture angle α can be set to, for example, 0 to ± 85 degrees.

  As a modification, the piezoelectric actuators 203 may be non-uniformly arranged along the circumferential direction of the small circle. In addition, the piezoelectric actuator 203 may be arranged uniformly or non-uniformly along a great circle on the surface of the stator 201 (a cut circle when the stator 201 is cut by a plane including its center) (in this case) The posture angle α in FIG. 2B is 0 degree). The number of piezoelectric actuators is not limited, and may be four or more, for example.

  Each piezoelectric actuator 203 includes a piezoelectric element. For example, an AC voltage in the ultrasonic range is applied to the piezoelectric element. The expansion and contraction of the piezoelectric element is controlled by changing the applied voltage characteristics (for example, amplitude, phase difference, frequency, etc.). Accordingly, the piezoelectric actuator 203 moves on the surface of the stator 201 by angular velocity vectors 205-1, 205-2, and 205-3, respectively.

  The electric power for driving the piezoelectric actuator 203 may be supplied from a power source inside the support mechanism 200 (for example, a battery mounted on the frame 209), or a power source outside the support mechanism 200 (for example, the base 213 or the base). 213 may be supplied by a cable, a wire, or wirelessly. This power can also be used to drive other members of the support mechanism 200 or other configurations connected to the support mechanism 200.

  The connection member 204 is, for example, a thin plate-like elastic member, and connects each piezoelectric actuator 203 along the circumferential direction of the frame 209. At this time, the connecting member 204 may apply a load to the stator 201 in advance by applying a force that biases the piezoelectric actuator 203 in one direction with respect to the center direction of the stator 201. In this case, the piezoelectric actuator 203 is prevented from being detached from the stator 201. The connection member 204 may be integrally formed with the frame 209, or may be connected to the frame 209 separately by bonding, welding, or fixing means (screws, nails, pins, etc.). As a modification, the frame 209 and the connection member 204 may be detachably connected to each other.

  The frame 209 has a ring shape and is disposed so as to surround the outer peripheral surface of the stator 201. The radius of the ring of the frame 209 is at least larger than the radius of the small circle or the great circle of the stator 201 on which the piezoelectric actuator 203 is disposed, and has a size that does not hinder the rotation of the frame 209 around the stator 201.

  As a modification, the frame 209 may have a flat plate shape that covers a part of the outer periphery of the stator 201 (see, for example, the frame 503 in FIG. 5) or other shapes such as a polygon. The frame 209 may have a point symmetric or axially symmetric shape, or an asymmetric shape.

  The frame 209 has an angular velocity vector formed by the resultant force of the angular velocity vectors 205-1, 205-2, and 205-3 due to the movement of the piezoelectric actuator 203 on the stator 201. As a result, the frame 209 rotates around the three axes (the yaw axis 207-1, the pitch axis 207-2, and the roll axis 207-3) with respect to the stator 201 within a predetermined movable range. As a modification, the frame 209 may be rotated only about any two of the three axes or about one axis.

  The frame 209 can support one or a plurality of supported bodies. In the example illustrated in FIG. 2A, one supported body 206 is fixed on the surface of the frame 209. The supported body 206 rotates relative to the stator 201 in conjunction with the movement of the frame 209.

  As a modification, the frame 209 may accommodate the supported body 206 inside the frame 209. Further, the frame 209 may indirectly support the supported body on the upper side, the side, or the lower side of the frame 209 using an attachment member. Such an attachment member may be integrally formed with the frame 209, or may be connected to the frame 209 by adhesion, welding, or fixing means (screws, nails, pins, etc.). The frame 209 may support the supported body 206 so as to be relatively movable with respect to the frame 209 by, for example, suspending the supported body 206 with a wire. The frame 209 may support the supported body 206 so as to be removable from the frame 209.

  The shaft 211 is, for example, a rod-shaped member that extends in the direction of the yaw axis 207-1. The shaft 211 is fixed to the stator 201 at one end, and fixed to the base 213 at the other end. That is, the shaft 211 connects the stator 201 and the base body 213 so that they cannot move relative to each other. The shape and size of the shaft 211 are not particularly limited. As a modification, the stator 201 and the base body 213 may be directly connected without using the shaft 211.

  The base 213 can be connected to other objects such as a movable body (for example, a moving body or a living body) or a stationary body (for example, a building). The base 213 may be connected to the surface of another object (for example, the inner surface or the outer surface of the moving body). The base 213 may constitute a part of another object (for example, a part of the casing of the moving body). The base 213 may be fixed so that it cannot move relative to other objects, or may be connected so that it can move relatively. The substrate may be removably connected to other objects. The base 213 may include an impact absorbing mechanism such as a damper in order to suppress vibrations from other connected objects from being transmitted to the support mechanism 200.

  With reference to FIG. 3, another example of the support mechanism is shown. The support mechanism 300 shown in FIG. 3 is different from the support mechanism 200 described in FIG. 2 in that the stator 315 can rotate around the yaw axis 301 with respect to the base body 303.

  The remaining configuration of the support mechanism 300 (stator 315, piezoelectric actuator 311, frame 313) is the same as or similar to the corresponding configuration of the support mechanism 200 (stator 201, piezoelectric actuator 203, frame 209). Can do. FIG. 3 shows a state in which three supported bodies 309 are supported on the frame 313, but the arrangement and number of the supported bodies 309 are not limited to this.

  As shown in FIG. 3, the shaft 307 is fixed to the stator 315 at one end and fixed to the rotor (rotor) of the motor 305 at the other end. A housing (stator) of the motor 305 is connected to the shaft 307. The motor 305 is, for example, a DC servo motor, and rotates around the yaw axis 301 in a desired direction (clockwise or counterclockwise). The motor 305 has an encoder and a potentiometer, for example, and can detect the rotation angle and rotation speed.

  The stator 315 is rotated around the yaw axis with respect to the base body 303 by the motor 305. That is, the rotation of the frame 313 relative to the base 303 is a combination of the rotation of the stator 315 around the yaw axis relative to the base 303 (rotation 1) and the rotation of the frame 313 relative to the stator 315 (rotation 2).

  The rotation of the frame 313 with respect to the stator 315 (rotation 2) may be rotation around two axes of the roll axis and the pitch axis. Even in this case, the frame 313 can rotate around the three axes of the yaw axis, the roll axis, and the pitch axis with respect to the base 303 by the rotation (rotation 1) of the stator 315 around the base 303 with respect to the base 303.

  The rotation (rotation 2) of the frame 313 with respect to the stator 315 may be rotation about three axes of the roll axis, the pitch axis, and the yaw axis. In this case, the motor 305 may be responsible for a large movement around the yaw axis and the piezoelectric actuator 311 may be responsible for a minute movement around the yaw axis.

  With reference to FIG. 4, the support position when the support mechanism supports a plurality of supported bodies will be described. 4A is an example in the case of supporting three supported bodies having the same weight, and FIG. 4B is an example in the case of supporting two supported bodies having different weights. In any example, the frame supports at least two of the plurality of supported bodies at positions opposite to each other with the rotor interposed therebetween. That is, the relative angle between one of the supported bodies and the other of the supported bodies (a half line extending from the center of the rotor to one supported body 401-1 and a half extending from the center of the rotor to the other supported body. The angle formed by the straight line) is greater than 90 degrees.

  As shown in FIG. 4A, the three supported bodies 401-1, 401-2, 401-3 (hereinafter also referred to as “supported body 401”) have the same weight and the stator 408. Are opposite to each other. More specifically, the supported body 401 has three piezoelectric actuators 410-1, 410-2, 410-3 (equal to each other in the circumferential direction of the ring-shaped frame 407 at equal intervals (relative angle of 120 degrees). Hereinafter, it is also called “piezoelectric actuator 410”).

  As a result, the center of gravity 405 of the frame 407 in a state of supporting the supported body 401 (including an object that rotates together with the frame 407 such as the supported body 401 and the piezoelectric actuator 410) is positioned on the yaw axis 403. That is, the weight of the frame 407 is balanced with respect to the yaw axis 403.

  Thereby, the torque required to maintain the frame 407 in the horizontal posture can be reduced. In addition, the center of gravity of the support mechanism can be prevented from changing as the frame 407 rotates about the yaw axis 403.

  The center of gravity 405 of the frame 407 is closer to the rotation center O than when the frame 407 supports only one supported body or when a plurality of supported bodies are supported only on the same side of the stator 408. It is close (may coincide with the rotation center O). Therefore, the torque when maintaining the posture with respect to the remaining rotation axis (pitch axis or roll axis) is also reduced. In addition, the center of gravity of the support mechanism can be prevented from changing as the frame 407 rotates around these rotational axes.

  This support mechanism may be attached to, for example, a UAV to support an imaging device such as a camera. In this case, for example, even if imaging is performed while the camera is maintained in the horizontal direction (direction parallel to the horizontal plane (ground)), less torque is required to maintain the frame 407 in the horizontal posture. That is, the electric power applied to the piezoelectric actuator 410 in order to maintain the horizontal posture of the camera can be reduced. Further, even if the camera is rotated in the horizontal direction toward the imaging target, the change in the center of gravity associated with the rotation of the frame 407 around the yaw axis 403 can be suppressed, so that the UAV balance during navigation can be prevented from being lost.

  FIG. 4B shows an example in which two supported bodies having different weights are supported. The supported bodies 411 and 413 are arranged along the circumferential direction of the frame 409, and are positioned so as to face each other (symmetrical position with a relative angle of 180 degrees). More specifically, the supported body 411 is positioned between the piezoelectric actuators 410-1 and 410-3 in the circumferential direction of the frame 409. The supported body 413 is positioned on the outer side in the radial direction of the frame 409 so as to face the piezoelectric actuator 410-2. The center of gravity of the frame 409 (including the object that rotates together with the supported bodies 411, 413, the three piezoelectric actuators 410-1, 410-2, 410-3, etc.) is on at least one rotation axis (for example, the yaw axis). To position.

  The position of the supported body on the frame can be appropriately changed according to the total number of supported bodies, the size, weight, shape, etc. of each supported body. For example, when the support mechanism or the frame is symmetrical with respect to the yaw axis, the weights of the multiple supported bodies are balanced on the yaw axis (so that the rotational moments with respect to each yaw axis cancel each other). You may place your body. For example, when supporting a plurality of supported bodies having the same weight, these supported bodies are arranged evenly around the yaw axis. On the other hand, when supporting a plurality of supported bodies having different weights, a heavy supported body is arranged closer to the yaw axis (so that the respective rotational moments with respect to the yaw axis cancel each other). Is placed further away from the yaw axis. Thereby, the weight with respect to the yaw axis of the frame which supported the to-be-supported body balances (a gravity center is located on a yaw axis).

  The types of the plurality of supported bodies may be the same or different from each other. For example, at least one of the supported bodies includes an imaging device (a omnidirectional camera, a hemispherical camera, a video camera, etc.), a sensor (an image sensor, an audio sensor, etc.), an image output device or an audio output device (a TV, a speaker, etc.) ) Or a device such as a communication device and a robot arm. For example, at least one of the supported bodies may be a weight for balancing the weight of the device. The weight may be separately attached to the frame, or may be integrally formed with the frame.

  With reference to FIG. 5, an example of a support mechanism provided with an inertial sensor is shown. As shown in the figure, the support mechanism 500 includes an inertial sensor 501, a flat frame 503, a spherical stator 505, a rod-shaped shaft 507, a supported body 509, a plurality of piezoelectric actuators 511, and the like. The support mechanism 500 may have the same or similar configuration as the support mechanism 100, the support mechanism 200, or the support mechanism 300 described with reference to FIGS. 1 to 3, for example, except that the inertia sensor 501 is provided. .

  The inertial sensor 501 is a sensor (Inertial Measurement Unit: IMU) for detecting the acceleration, angular velocity, or angular acceleration of an object. For example, three angular velocity sensors (gyro sensors) and three acceleration sensors with respect to three axes of the sensor. It is a sensor group to which is attached. As a modification, the inertial sensor 501 may include a geomagnetic sensor, a tilt sensor, a GPS, and the like for correcting an error of an angular velocity sensor or an acceleration sensor. One or a plurality of inertial sensors 501 may be provided.

  The inertial sensor 501 is fixed on the surface of the flat frame 503. The supported body 509 supported by the frame 503 may be one whose position and orientation are controlled according to the imaging target, such as a camera. When the supported body 509 includes a control device, the inertial sensor 501 may be electrically connected to the control device of the supported body 509.

  When the frame 503 rotates around the stator 505, the inertial sensor 501 and the supported body 509 also rotate around the stator 505. That is, the movement of the inertial sensor 501 is interlocked with the movement of the frame 503 and the supported body 509. Here, the positional relationship between the inertial sensor 501, the frame 503, and the supported body 509 is known. Therefore, the inertial sensor 501 can detect the movement of the frame 503 and the supported body 509 (for example, position, posture, angular velocity, angular acceleration, etc.). That is, a complicated configuration such as an encoder is not necessary for motion detection. The detected movement is used for controlling the positions and postures of the frame 503 and the supported body 509.

  The inertial sensor 501 may be integrally formed with the frame 503, or may be connected so that it cannot be removed by adhesion, welding, or fixing means (screws, nails, pins, etc.). The position and number of inertial sensors 501 in the frame 503 can be set as appropriate. For example, the inertial sensor 501 may be attached on or near the supported body 509 that is a target for detecting motion.

  As a modification, the inertial sensor 501 may be detachably connected to the frame 503. Further, the inertial sensor 501 may be indirectly connected to the frame 503 via another member such as a damper.

  A method for calibrating (initializing) the support mechanism using such an inertial sensor will be described with reference to FIGS. As shown in FIG. 6, the support mechanism 600 includes a frame 605 that is rotatably connected to a spherical stator 602 via a plurality of piezoelectric actuators 604. An inertial sensor 609 is fixed to the frame 605 and one or a plurality of supported bodies 610 are supported.

  The support mechanism 600 is connected to the base 603 through a shaft 606 connected to the stator 602. The base 603 includes a sensor 607. The frame 605 rotates about three axes (yaw axis 601-1, pitch axis 601-2, and roll axis 601-3) with respect to the stator 602 and the base body 603. For example, the support mechanism 600 may have the same or similar configuration as the support mechanism 500 shown in FIG.

  The inertial sensor 609 may include, for example, a geomagnetic sensor in addition to an acceleration sensor and an angular velocity sensor. In this case, the inertial sensor 609 detects the attitude angle of the frame 605 with respect to the pitch axis 601-2 and the roll axis 601-3 with an acceleration sensor and an angular velocity sensor, and the attitude angle of the frame 605 with respect to the yaw axis 601-1 is determined by a geomagnetic sensor ( For example, it may be detected by a compass.

  The sensor 607 is a sensor that detects the position or orientation of the base 603. The sensor 607 is an inertial sensor, for example, and may include an acceleration sensor, an angular velocity sensor, and a geomagnetic sensor. For example, the sensor 607 may detect a posture angle of the base 603 with respect to the yaw axis 601-1 with a geomagnetic sensor (for example, a compass).

  The sensor 607 is fixed to the base 603. The sensor 607 may be integrally formed with the base 603, or may be connected so that it cannot be removed by adhesion, welding, or fixing means (screws, nails, pins, etc.).

  As a modification, for example, when the base 603 is fixed to a movable body and the movement of the base 603 and the movable body is interlocked, the sensor 607 is provided on the movable body instead of the base 603, and the sensor 607 detects the position or posture of the movable body. You may do it.

  A calibration (initialization) procedure of the support mechanism 600 will be described with reference to FIG. Calibration can be performed by, for example, a control device provided on the support mechanism 600, the supported body 610, the base 603, the movable body, or the like. The control device includes, for example, a CPU (Central Processing Unit) and a storage medium such as a semiconductor memory, and executes programs stored in the storage medium to realize various functions.

  In step 701, the attitude angle of the frame 605 with respect to the pitch axis 601-2 and the roll axis 601-3 is detected by the inertial sensor 609.

  In step 703, the control device rotates the frame 605 around the pitch axis 601-2 and the roll axis 601-3 to the reference position based on the attitude angle detected in step 701. The reference position may be, for example, a predetermined position outside the support mechanism 600 (for example, a fixed position such as the ground (horizontal)) or the main plane of the base 603. As a modification, step 703 may be performed simultaneously with step 707 or after step 707.

  In step 705, the attitude angle of the frame 605 with respect to the yaw axis 601-1 is detected by, for example, a geomagnetic sensor of the inertial sensor 609. Further, the attitude angle of the base 603 with respect to the yaw axis 601-1 is detected by using, for example, a geomagnetic sensor of the inertial sensor 609.

  In step 707, the control device rotates the frame 605 around the yaw axis 601-1 to the reference position based on the attitude angles of the frame 605 and the base 603 detected with respect to the yaw axis 601-1 detected in step 705. When the base 603 is attached to the movable body, the reference position may be, for example, the traveling direction of the movable body. When the stator 602 is connected to the base body 603 so as to be rotatable around the yaw axis, the control device may rotate the stator 602 relative to the base body 603.

  A method for determining the output (torque) of the piezoelectric actuator by feedback control using such an inertial sensor will be described with reference to FIG. The feedback control can include P control, PD control, PI control, PID control, or a combination thereof. Here, an example using PID control will be described.

  As shown in FIG. 8, the feedback loop 800 includes a control device 802, a sensor 804 (for example, an inertial sensor), an actuator 806 (for example, a piezoelectric actuator), a frame 808, and the like. Here, the sensor 804, the actuator 806, and the frame 808 are, for example, the configuration corresponding to the support mechanism 500 in FIG. 5 or the support mechanism 600 in FIG. 6 (inertia sensors 501 and 609, piezoelectric actuators 511 and 604, frames 503 and 605). The same or similar configuration can be used.

  The control device 802 includes, for example, a CPU (Central Processing Unit) and a storage medium such as a semiconductor memory. The control device 802 executes programs stored in the storage medium and realizes various functions. The control device 802 is connected to the support mechanism frame (for example, the frame 503 of the support mechanism 500 in FIG. 5 and the frame 605 of the support mechanism 600 in FIG. 6), the base (for example, the base 603 in FIG. 6), and the base. Provided in part or all of the movable body.

  A target (predetermined) posture angle 810 is input to the control device 802. The posture angle 810 is, for example, a desired posture (roll angle, pitch angle, yaw angle) of the frame or the supported body. In addition, the attitude angle 812 of the frame 808 is input from the sensor 804 to the control device 802. The posture angle 812 is calculated, for example, by integrating the current or latest angular velocity of the frame 808 detected by the angular velocity sensor (gyro sensor) of the sensor 804.

  The control device 802 calculates a difference 814 between the posture angle 810 and the posture angle 812 and inputs it to the first PID controller 816. An angular velocity 818 output from the first PID controller 816 is an angular velocity for setting the frame 808 in a desired posture.

  The angular velocity 820 of the frame 808 is input from the sensor 804 to the control device 802. The angular velocity 820 is, for example, the current or latest angular velocity of the frame 808 detected by the angular velocity sensor (gyro sensor) of the sensor 804.

  The control device 802 calculates a difference 822 between the angular velocity 818 and the angular velocity 820 and inputs it to the second PID controller 824. Torque 826 output from the second PID controller is torque that the actuator 806 should output in order to place the frame 808 in a desired posture.

  Control device 802 sends a command to actuator 806 to output torque 826. Upon receiving the command, the actuator 806 applies torque 826 to the stator of the support mechanism and moves on the stator. Thereby, the frame 808 is rotated toward a desired posture.

  With reference to FIG. 9, the control method of a support mechanism is demonstrated. This control method can be applied to both the support mechanism described with reference to FIGS. 1 to 8 and its modification. The control of the support mechanism may be performed using, for example, the control device 802 described with reference to FIG. 8, or another control device may be used.

  In step 901, prior to rotating the frame of the support mechanism, the control device calibrates (initializes) the support mechanism. The control device aligns the frame with respect to a reference position (for example, the horizontal direction and the traveling direction of the movable body, for example) using the calibration method described in steps 701 to 707 in FIG.

  In step 903, the control device detects the movement of the frame using an inertial sensor (for example, the inertial sensor 501 in FIG. 5 or the inertial sensor 609 in FIG. 6) provided in the frame.

  In step 905, the control device performs the PID control described with reference to FIG. 8, for example, based on the frame motion detected in step 903. The control device drives the piezoelectric actuator based on the torque determined by the PID control, and rotates the frame to a desired posture.

  With reference to FIG. 10, the movable body to which the support mechanism is attached will be described. Here, UAV will be described as an example. As shown in the figure, the UAV 1000 includes four rotor blades 1002, 1004, 1006, and 1008 that are located at a predetermined distance 1010 from each other. The UAV 1000 flies by generating lift and propulsion by the rotation of these rotor blades. The UAV 1000 can perform manual flight by a user operation, automatic flight that flies in a preset route, and the like.

  As a modification, the number of rotor blades of the UAV 1000 is not limited to four, and may be one or more. Further, the UAV 1000 may have a fixed wing without having a rotary wing, or may have both a rotary wing and a fixed wing.

  An example in which a support mechanism is attached to such a UAV will be described with reference to FIG. As shown in the figure, the UAV 1100 includes a propulsion mechanism 1106 such as a rotor blade, a sensor system 1108, a communication system 1110, and the like. A support mechanism 1102 is connected to the UAV 1100. The support mechanism 1102 can support the supported body 1104.

  As the support mechanism 1102 and the supported body 1104, the support mechanism and the supported body described with reference to FIGS. 1 to 9 can be used as appropriate. The support mechanism 1102 is connected to the center of the bottom surface of the UAV 1100, for example.

  The support mechanism 1102 can support, for example, a plurality of cameras (for example, two) as the supported body 1104. For example, the support mechanism 1102 rotates the camera around the yaw axis, the pitch axis, and the roll axis, and adjusts the posture of the camera while the UAV 1100 is sailing.

  At this time, the support mechanism 1102 can balance the weight of the supported body 1104 (a plurality of cameras) with respect to the rotation axis or the rotation center, as described with reference to FIG. Thereby, even if the posture of the camera is changed during navigation, it is possible to suppress the change in the center of gravity accompanying the rotation. Therefore, it is possible to suppress the balance of the UAV 1100 during navigation from being lost. The support mechanism 1102 functions as a gimbal that supports a plurality of cameras of the UAV 1100.

  The sensor system 1108 is various sensors for detecting the state of the UAV 1100. The sensor system 1108 acquires the position, posture, velocity, angular velocity, acceleration, or the like of the UAV 1100 using, for example, a GPS, a motion sensor, an inertial sensor, a proximity sensor, or the like. The sensor system 1108 may include, for example, the sensor 607 described with reference to FIG.

  The communication system 1110 communicates with the external terminal 1112 via the network 1116 in one or both directions. The communication from the external terminal 1112 may include a control command for changing the positions and postures of the UAV 1110, the support mechanism 1102, and the supported body 1104, for example. Communication from the communication system 1110 may include information about the state of the UAV 1100 detected by the sensor system 1108.

  The network 1116 includes, for example, one or more of wireless, WiFi, local area network (LAN), wide area network (WAN), infrared, point-to-point (P2P) network, telecommunications network, cloud communication, and the like.

  The external terminal 1112 has a communication system 1114 that communicates with the UAV 1100. The communication system 1114 may be connected to the Internet or other network so that data can be uploaded to a website or server or downloaded from the website.

  The external terminal 1112 may be a handheld or wearable device. The external terminal 1112 can be configured by, for example, a smartphone, a tablet, a laptop, a computer, glasses, gloves, a helmet, a microphone, or a combination thereof.

  The external terminal 1112 can include a user interface such as a keyboard, a mouse, a joystick, a touch screen, or a display. The external terminal 1112 can include a display device that displays information from the UAV 1100, for example.

  The present invention is not limited to the above-described embodiment, and can be implemented with various other modifications within the scope not departing from the gist of the present invention. That is, the above-described aspects are merely examples in all respects, and are not interpreted in a limited manner, and various modifications can be employed.

DESCRIPTION OF SYMBOLS 1 ... System, 100 ... Support mechanism, 101 ... Movable body, 103 ... Base | substrate, 105 ... Stator, 107 ... Frame, 109 ... Actuator, 111 ... Motor assembly 200 ... Support mechanism, 201 ... Stator, 203, 203-1, 203-2, 203-3 ... Piezoelectric actuator, 204 ... Connection member, 205-1, 205-2, 205-3 ... Angular velocity vector, 206 ... Covered Support, 207-1 ... Yaw axis, 207-2 ... Pitch axis, 207-3 ... Roll axis, 209 ... Frame, 211 ... Shaft, 213 ... Substrate 300 ... Support mechanism, 301 ... Yaw axis, 303 ... base, 305 ... motor, 307 ... shaft, 309 ... supported body, 311 ... piezoelectric actuator, 313 ... frame, 315 ... stator 401, 4 1-1, 401-2, 401-3: Supported body, 405: Center of gravity, 407, 409 ... Frame, 408 ... Stator, 410 ... Piezoelectric actuator, 411, 413 ......... Supported Body 500: Support mechanism, 501 ... Inertia sensor, 503 ... Frame, 505 ... Stator, 507 ... Shaft, 509 ... Supported body, 511 ... Piezoelectric actuator 600 ... Support mechanism, 601-1 ... Yaw axis, 601-2 ... Pitch axis, 601-3 ... Roll axis, 602 ... Stator, 603 ... Base, 604 ... Piezoelectric actuator, 605 ... Frame, 606 ... Shaft, 607 ... ... Sensor, 609 ... Inertia sensor, 610 ... Supported body 800 ... Feedback loop, 802 ... Control device, 804 ... Sensor, 806 ... Actuator, 8 8 ... Frame, 810, 812 ... Attitude angle, 814 ... Difference, 816 ... First PID controller, 818, 820 ... Angular velocity, 822 ... Difference, 824 ... Second PID controller, 826 ... Torque 1002, 1004, 1006, 1008 ... Rotary blades, 1010 ... Separation distance 1102 ... Support mechanism, 1104 ... Supported body, 1106 ... Propulsion mechanism, 1108 ... Sensor system, 1110 ... Communication system, 1112 ... ... External terminal, 1114 ... Communication system, 1116 ... Network

Claims (7)

A first member having a curved surface;
A plurality of actuators moving on the surface;
A second member connected to the plurality of actuators and rotating around the first member,
The second member is capable of supporting at least two of the plurality of supported bodies at positions opposite to each other with the first member interposed therebetween, and is rotatable around the yaw axis of the first member,
The center of gravity of the second member supporting the plurality of supported bodies is located on the yaw axis.
Support mechanism. The support mechanism according to claim 1, further comprising an inertial sensor attached to at least one of the second member or the plurality of supported bodies. Wherein the plurality of actuators contacts the said surface of the first member, the support mechanism according to claim 1 or 2. The first member is a sphere;
The support mechanism according to any one of claims 1 to 3 , wherein the plurality of actuators are arranged at equal intervals along the same circumference of the sphere surface. Wherein the first member is fixed to the base body, the support mechanism according to any one of claims 1 to 4. The support mechanism according to any one of claims 1 to 5 , wherein the support mechanism is connected to a moving body via a base connected to the first member. A support mechanism according to any one of claims 1 to 6 ;
A moving body to which the support mechanism is attached;
A system comprising: