Gimbal device and camera system comprising the same

Abstract

To provide a gimbal device which suppresses a burden acting on each motor and suppresses a situation of a gimbal lock even when a centroid position of a camera is varied.SOLUTION: A gimbal device (2) comprises: a camera mount part (6); a first motor (8); a first coupling member (14); a second motor (10); a second coupling member (16); a third motor (12); a third coupling member (18); a support part (20) for supporting the gimbal device; and a control part (20b) for controlling the first, second, and third motors. A fitting surface (6a) of the camera mount part is directed to a direction inclined to a first plane including first and second axes, in a state of forming a right angle by the first and second coupling members. An axis extending along the fitting surface and parallel to the first plane is obliquely directed to the first and second axes in view from a direction orthogonal to the first plane.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gimbal device, and more particularly to a gimbal device to which a camera is attached for use, and a camera system including the gimbal device. [Background technology]

[0002] There is known a gimbal device that is used by mounting a camera and controls the optical axis of the camera to always point in a predetermined direction. Such a gimbal device includes first, second, and third arms that are substantially L-shaped, and first, second, and third motors that connect each arm to a base (support). When the camera mounted on the gimbal device is to be oriented in a desired direction, each motor is rotated to change the relative angle between each L-shaped arm.

[0003] Here, in a gimbal device of a general structure, if the mass of each arm, motor, etc. is sufficiently small compared to the mass of the camera, the load on each motor can be reduced by adjusting the extension line of each rotation shaft of the first, second, and third motors to pass near the center of gravity of the camera. In other words, if the extension line of the rotation shaft of each motor passes near the center of gravity of the camera, the torque that needs to be generated by each motor to maintain the attitude of the camera can be made extremely small regardless of the direction in which the camera is pointed. Note that even if the mass of each arm, motor, etc. cannot be ignored, the torque generated by each motor can be made sufficiently small by setting the position of the center of gravity taking these masses into account.

[0004] However, for example, when a camera with a zoom function is attached to a gimbal device, the position of the center of gravity of the camera changes, which is a problem.Even if the center of gravity of the camera is adjusted so that the torque to be generated by each motor is small at a certain angle of view, if the center of gravity is moved by changing the angle of view of the camera, the torque to be generated by each motor increases.

[0005] The present inventor solved this problem with the invention described in JP 2021-103214 A (Patent Document 1). That is, in the invention described in Patent Document 1, the axis perpendicular to the optical axis of the camera is obliquely oriented with respect to the extension line of the rotation shaft of the first motor, thereby successfully alleviating this problem. In the gimbal device described in Patent Document 1, when the position of the center of gravity of the camera changes, the torque required to maintain the attitude of the camera is distributed to multiple motors, thereby reducing the burden on each motor. [Prior art documents] [Patent documents]

[0006] [Patent Document 1] JP 2021-103214 A Summary of the Invention [Problem to be solved by the invention]

[0007] However, the gimbal device described in Patent Document 1 has a problem that the gimbal device is prone to a so-called "gimbal lock" state during use. Gimbal lock refers to a state in which the two rotation axes for rotating the camera of the gimbal device are almost parallel. This gimbal lock occurs when the motor provided at the middle of the three motors is rotated to a position where the two arms extending from this motor are in a straight line. In this state, the camera cannot be rotated around the three rotation axes, and therefore the camera cannot be rotated in a desired direction by the gimbal device. In addition, even if the gimbal lock does not reach a complete state, when the gimbal lock state approaches, it becomes difficult to effectively control the attitude of the camera, and the control of the gimbal device becomes unstable.

[0008] Therefore, an object of the present invention is to provide a gimbal device that is less likely to fall into a gimbal lock state under normal usage conditions while suppressing the burden on each motor even when the center of gravity of the camera changes, and a camera system equipped with the same. [Means for solving the problem]

[0009] In order to solve the above-mentioned problems, the present invention provides a gimbal device for use with a camera attached, comprising: a camera mount section having an attachment surface for fixing the optical axis of the camera in a predetermined direction; a first motor for rotating the camera mount section about a first axis; a first connecting member for connecting the camera mount section and the first motor; a second motor for rotating the camera mount section about a second axis; a second connecting member for connecting the first motor and the second motor; a third motor for rotating the camera mount section about a third axis; The camera mount unit has a third connecting member that connects the motor and the third motor, a support portion connected to the third motor for supporting the gimbal device, and a control portion that controls the first, second, and third motors, and is characterized in that, when the first connecting member and the second connecting member form a right angle, the mounting surface of the camera mount unit is oriented in a direction inclined with respect to a first plane that includes the first axis and the second axis, and an axis that extends along the mounting surface and is parallel to the first plane is oriented obliquely with respect to the first axis and the second axis when viewed from a direction perpendicular to the first plane.

[0010] According to the present invention configured as described above, the axis parallel to the first plane extending along the mounting surface is oriented obliquely with respect to the first axis and the second axis when viewed from a direction perpendicular to the first plane, so that a motor with a lower output can be used to deal with the movement of the center of gravity in the optical axis direction of the camera. That is, in the conventional gimbal device, the rotation axis of the first motor connected to the camera mount is oriented in a direction perpendicular to the optical axis of the camera. Therefore, when the center of gravity of the camera moves in the optical axis direction, only the first motor generates torque to cancel the moment generated by this movement. Therefore, when the center of gravity of the camera moves, the first motor needs to generate extra torque equal to the movement distance of the center of gravity multiplied by the weight of the camera in order to maintain the attitude of the camera.

[0011] In contrast, according to the present invention configured as described above, the axis parallel to the first plane extending along the mounting surface is oriented obliquely with respect to the first axis and the second axis. Therefore, the torque for canceling the moment generated by the movement of the center of gravity of the camera is not concentrated in one motor, but the canceling torque is shared by multiple motors. This increases the margin of output of each motor, making it possible to respond to the movement of the center of gravity of the camera with a motor with a lower output.

[0012] Furthermore, according to the present invention configured as described above, the mounting surface of the camera mount is oriented in a direction inclined with respect to a first plane including the first axis and the second axis when the first connecting member and the second connecting member form a right angle. Therefore, the optical axis of the camera mounted on the mounting surface is oriented horizontally when the support is tilted. As a result, when the support is tilted, the gimbal device can be kept away from gimbal lock, and the occurrence of gimbal lock in the normal use range of the gimbal device can be suppressed.

[0013] The present invention also provides a camera system equipped with a gimbal device that supports a camera, the camera system comprising the gimbal device of the present invention and a camera attached to the gimbal device. Effect of the Invention

[0014] The gimbal device of the present invention and the camera system equipped with the same can reduce the burden on each motor and make it less likely to fall into a gimbal lock state under normal usage conditions, even if the position of the center of gravity of the camera changes. [Brief description of the drawings]

[0015] [Figure 1] 1 is a perspective view showing the appearance of a camera system according to a first embodiment of the present invention. [Diagram 2] 1 is a perspective view showing a gimbal device according to a first embodiment of the present invention in a basic state with a mounting surface facing horizontally. FIG. [Diagram 3] 1 is a view showing a gimbal device according to a first embodiment of the present invention, viewed from a direction perpendicular to a mounting surface. [Figure 4] FIG. 11 is an explanatory diagram illustrating a schematic relationship between the rotation shafts of motors and the attitude angle of a camera in a conventional gimbal device. [Diagram 5] FIG. 1 is an explanatory diagram that illustrates a schematic relationship between the rotation axes of motors in the gimbal device described in Patent Document 1 and the attitude angle of the camera. [Figure 6] FIG. 2 is an explanatory diagram illustrating a schematic relationship between the rotation shafts of motors in the gimbal device according to the first embodiment of the present invention and the attitude angle of the camera. [Figure 7] FIG. 1 is a perspective view showing the gimbal device described in Patent Document 1 in a basic state. [Figure 8] FIG. 1 is a perspective view showing a state in which the gimbal device described in Patent Document 1 is tilted forward at 45 degrees. [Figure 9] FIG. 1 is a perspective view showing a state in which the gimbal device described in Patent Document 1 is tilted forward by 90 degrees. [Figure 10] 1 is a perspective view showing a gimbal device according to a first embodiment of the present invention, with a grip portion facing vertically upward. FIG. [Figure 11] 1 is a perspective view showing a state in which a gimbal device according to a first embodiment of the present invention is tilted forward at 45 degrees. FIG. [Figure 12] 1 is a perspective view showing a state in which a gimbal device according to a first embodiment of the present invention is tilted forward by 90 degrees. FIG. [Figure 13] FIG. 11 is a perspective view showing a gimbal device according to a second embodiment of the present invention in a basic state. [Figure 14] 11 is a perspective view showing a gimbal device according to a second embodiment of the present invention, with a grip portion facing vertically downward and the optical axis of the camera facing horizontally. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0016] Next, a camera system according to an embodiment of the present invention will be described with reference to the accompanying drawings. Fig. 1 is a perspective view showing a camera system according to a first embodiment of the present invention, showing a state in which a gimbal device is in a basic state. Fig. 2 is a perspective view showing the gimbal device in the basic state with the mounting surface facing horizontally. Fig. 3 is a view of the gimbal device according to the first embodiment of the present invention, seen from a direction perpendicular to the mounting surface.

[0017] As shown in FIG. 1, a camera system 1 according to a first embodiment of the present invention is made up of a gimbal device 2 and a camera 4 attached to this gimbal device 2. In the camera system 1, the camera 4 can be aimed in a desired direction by operating a joystick provided on the grip of the gimbal device 2. In addition, by selecting various operation modes of the gimbal device 2, it is possible to take pictures according to the photographer's intentions while suppressing shaking of the field of view of the camera 4.

[0018] Camera 4 is a digital video camera for shooting moving images, and has a zoom function. Camera 4 is configured such that, when the angle of view is changed by the zoom function, its lens barrel 4a expands and contracts, and accordingly, the center of gravity of camera 4 moves along optical axis A of camera 4. Although camera 4 is a digital video camera for shooting moving images, gimbal device 2 can be applied to any camera for shooting moving images or still images.

[0019] 1, the gimbal device 2 has a camera mount 6 for mounting a camera 4, a first motor 8 for rotating the camera mount 6 about a first axis A1, a second motor 10 for rotating the camera mount 6 about a second axis A2, and a third motor 12 for rotating the camera mount 6 about a third axis A3. The gimbal device 2 further has a first connecting member 14 for connecting the camera mount 6 and the first motor 8, a second connecting member 16 for connecting the first motor 8 and the second motor 10, a third connecting member 18 for connecting the second motor 10 and the third motor 12, and a gripping portion 20 which is a support portion to be gripped by the photographer.

[0020] 1 also shows the basic state of the gimbal device 2 (a state in which the first connecting member 14 and the second connecting member 16 form a right angle, and the second connecting member 16 and the third connecting member 18 form a right angle). In this basic state, the first axis A1, the second axis A2, and the third axis A3 are oriented in different directions and are perpendicular to each other. That is, in the basic state shown in FIG. 1, when the grip portion 20 is oriented to extend vertically, the first connecting member 14 is oriented to extend in a vertical plane, the second connecting member 16 is oriented to extend in a horizontal plane, and the third connecting member 18 is oriented to extend in a vertical plane.

[0021] Furthermore, in the basic state, the lens barrel 4a of the camera 4 is set to the wide end (the state in which the lens barrel 4a is at its shortest), and the center of gravity of the camera 4 in this state is located at point G1. Note that in the following description, it is assumed that the masses of the first to third connecting members and the first to third motors are sufficiently small compared to the mass of the camera 4 and can be ignored.

[0022] The camera mount 6 also includes a flat mounting surface 6a for fixing the camera 4. In the present embodiment, in the basic state shown in FIG. 1, the mounting surface 6a is configured as a rectangular flat surface oriented in a direction inclined with respect to a first plane P1 including the first axis A1 and the second axis A2. In the present embodiment, the mounting surface 6a of the camera mount 6 is configured to form an angle of about 45 degrees with respect to the first plane P1. Preferably, the mounting surface 6a is configured to form an angle of about 15 degrees to about 75 degrees with respect to the first plane P1, and more preferably, the mounting surface 6a is configured to form an angle of about 30 degrees to about 60 degrees with respect to the first plane P1.

[0023] Furthermore, the front edge 6b of the mounting surface 6a is obliquely (non-parallel and non-perpendicular) oriented to the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane P1. In other words, an axis parallel to the first plane P1 extending along the mounting surface 6a, such as the front edge 6b, is obliquely oriented to the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane. In this embodiment, the front edge 6b of the mounting surface 6a is configured to form an angle of about 45 degrees with the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane P1. Preferably, the front edge 6b of the mounting surface 6a is configured to form an angle of about 15 degrees to about 75 degrees with respect to the first axis A1 when viewed from a direction perpendicular to the first plane P1, and more preferably, to form an angle of about 30 degrees to about 60 degrees.

[0024] The camera mount section 6 is configured to mount the camera 4 such that its front edge 6b is parallel to the front edge 4b ​​of the housing of the camera 4. As a result, the camera 4 is mounted to the camera mount section 6 such that the optical axis A is perpendicular to the front edge 6b of the camera mount section 6 when viewed from a direction perpendicular to the mounting surface 6a. In this state, the mounting surface 6a of the camera mount section 6 and the optical axis A of the camera 4 are oriented parallel to each other. Therefore, in the basic state shown in FIG. 1, when the grip section 20 is oriented to extend vertically upward, the optical axis A of the camera 4 is oriented obliquely upward with respect to the horizontal plane.

[0025] The first motor 8 is provided to rotate the first connecting member 14 and the second connecting member 16 relative to one another, and is connected to the camera mount unit 6 via the first connecting member 14. The first motor 8 is configured to rotate the camera mount unit 6 and the camera 4 attached thereto about the first axis A1 in the basic state via the first connecting member 14. In this embodiment, the first connecting member 14 is bent in an L-shape, so that the mounting surface 6a of the camera mount unit 6 is located below the first axis A1 in FIG. 1, and the center of gravity G1 of the camera 4 attached to the mounting surface 6a is located approximately on the first axis A1.

[0026] The second motor 10 is provided so as to rotate the second connecting member 16 and the third connecting member 18 relative to each other, and is connected to the first motor 8 via the second connecting member 16. As a result, the second motor 10 rotates the camera mount unit 6 and the camera 4 attached thereto about the second axis A2 in the basic state via the second connecting member 16, the first motor 8, and the first connecting member 14. When the grip unit 20 is oriented vertically in the basic state shown in FIG. 1, the second connecting member 16 is formed so as to bend and extend in a horizontal plane, and as a result, the second axis A2 is oriented so as to intersect the first axis A1 at a right angle in the horizontal plane. In addition, the center of gravity G1 of the camera 4 attached to the camera mount unit 6 is located approximately at the intersection of the first axis A1 and the second axis A2.

[0027] The third motor 12 is provided so as to rotate the third connecting member 18 and the gripping portion 20 relative to each other, and is connected to the second motor 10 via the third connecting member 18. As a result, the third motor 12 rotates the camera mount portion 6 and the camera 4 attached thereto about the third axis A3 in the basic state via the third connecting member 18, the second motor 10, the second connecting member 16, the first motor 8, and the first connecting member 14. In addition, the third connecting member 18 is formed so as to bend and extend within a vertical plane, so that the third axis A3 intersects at right angles with the first axis A1 and the second axis A2, which are oriented in the horizontal direction. In other words, the first axis A1, the second axis A2, and the third axis A3 are perpendicular to each other. Further, the center of gravity G1 of the camera 4 attached to the camera mount portion 6 is located approximately at the intersection of the first axis A1, the second axis A2, and the third axis A3.

[0028] The grip unit 20 is a round bar-shaped member attached to the third motor 12, extends vertically downward from the underside of the third motor 12, and is held by the photographer. An operation unit 20a is provided on the side of the grip unit 20, and by operating this operation unit 20a, the camera 4 attached to the camera mount unit 6 can be aimed in a desired direction. By operating the operation unit 20a, the operation mode of the gimbal device 2 can be selected, and a holding mode, a tracking mode, etc. can be set.

[0029] Furthermore, the gripping unit 20 has a built-in control unit 20b that controls the first motor 8, the second motor 10, and the third motor 12. The control unit 20b calculates the rotation angle of each motor required to orient the camera 4 in a predetermined direction based on detection signals from a rotary encoder (not shown) built into each motor and a gyro sensor (not shown) built into the gripping unit 20. The control unit 20b is configured to send a control signal to each motor based on the calculated rotation angle of each motor, and to control the attitude of the camera 4 attached to the camera mount unit 6.

[0030] 1, the grip portion 20 is configured from a vertically oriented round bar-shaped member, but the grip portion 20 can be configured in various shapes. For example, the grip portion can be configured from a horizontally oriented base member with handle portions provided on both ends. Alternatively, the grip portion can be configured as a support portion for attaching the gimbal device 2 to various support structures.

[0031] As described above, in the gimbal device 2 of this embodiment, the mounting surface 6a of the camera mount portion 6 is inclined at 45 degrees. Therefore, when the grip portion 20 of the gimbal device 2 in the basic state shown in FIG. 1 is directed vertically upward, the optical axis A of the camera 4 is directed 45 degrees upward. Then, by inclining the grip portion 20 forward at 45 degrees in a vertical plane including the optical axis A of the camera 4 in the state of FIG. 1, the optical axis A of the camera 4 is directed horizontally as shown in FIG. 2. Here, the center of gravity G1 of the camera 4 is located near the intersection of the axes around which the motors rotate. Therefore, even in the state shown in FIG. 2, the moment of force that the gravity acting on the center of gravity of the camera 4 acts around the axis of each motor is very small, and the camera 4 can be maintained in any posture by only outputting a small torque from each motor.

[0032] Here, in a conventional gimbal device (not shown), in a basic state, the mounting surface of the camera 4 and a first plane P1 including the first axis A1 and the second axis A2 are oriented parallel to each other. The optical axis A of the camera 4 and the second axis A2 are also oriented parallel to each other. Therefore, the camera 4 can be pitched (rotated about a horizontal axis perpendicular to the optical axis A of the camera 4) simply by rotating the first motor 8. Furthermore, in a conventional gimbal device (not shown), the camera 4 can be rolled (rotated about the optical axis A of the camera 4) simply by rotating the second motor 10.

[0033] In contrast, in the gimbal device 2 of this embodiment, as shown in Fig. 2, in the basic state, the front edge 6b of the camera mount portion 6 is oriented obliquely (non-parallel and non-perpendicular) to the first axis A1 and the second axis A2, and the camera 4 is configured to be attached parallel to this front edge 6b. For this reason, in the gimbal device 2 of this embodiment, the camera 4 cannot be pitched by only rotating the first motor 8, and the camera 4 cannot be rolled by only rotating the second motor 10. In the gimbal device 2 of this embodiment, when pitching or rolling the camera 4, it is necessary to rotate mainly the first motor 8 and the second motor 10 simultaneously by the control unit 20b.

[0034] That is, in the gimbal device 2 of this embodiment, as shown in Fig. 3, the first axis A1 and the second axis A2 are both obliquely oriented with respect to the axis AR perpendicular to the optical axis A of the camera 4 when viewed from a direction perpendicular to the mounting surface 6a of the camera mount section 6. As a result, when the camera 4 mounted on the mounting surface 6a of the camera mount section 6 is pitched, the first motor 8 and the second motor 10 are rotated simultaneously, and when the camera 4 is rolled, the first motor 8 and the second motor 10 are rotated simultaneously. Even when the camera 4 is pitched or rolled, the center of gravity G1 of the camera 4 is located near the intersection of the first to third axes around which the first to third motors rotate, so that the camera 4 can be maintained in any posture by only outputting a slight torque from each motor.

[0035] On the other hand, when the angle of view of the lens barrel 4a is changed to the telephoto end side using the zoom function of the camera 4, the lens barrel 4a is extended. Accordingly, the center of gravity G1 of the camera 4 moves a distance L in the direction of the optical axis A to the center of gravity G2 (FIG. 3). When the center of gravity moves from G1 to G2 in this way, the distance from the intersection of the first to third axes to the center of gravity G2 becomes longer. In this state, the moment of force generated around the first axis A1 and the second axis A2 by the gravity acting on the center of gravity G2 becomes large. As a result, when the center of gravity moves to G2, the torque that the first motor 8 and the second motor 10 should generate in order to maintain the attitude of the camera 4 becomes relatively large. In other words, when the center of gravity of the camera 4 is located at G1, the output torque required of each motor to maintain the attitude of the camera 4 is extremely small, but when the center of gravity moves to G2, the output torque required to maintain the attitude increases.

[0036] That is, to cancel the force moment generated by gravity, the first motor 8 generates a torque obtained by multiplying the weight of the camera 4 by the distance L1 from the first axis A1 to the center of gravity G2. The second motor 10 generates a torque obtained by multiplying the weight of the camera 4 by the distance L2 from the second axis A2 to the center of gravity G2. These torques are smaller than the torque obtained by multiplying the weight of the camera 4 by the moving distance L of the center of gravity. In this way, in the gimbal device 2 of this embodiment, the torque burden required to maintain the attitude of the camera 4 is distributed to the first motor 8 and the second motor 10, and the torque that each motor must generate is reduced.

[0037] As described above, in this embodiment, the front edge 6b of the mounting surface 6a is configured to form an angle of approximately 45 degrees with respect to the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane P1. Therefore, when the masses of the first to third connecting members and the first to third motors are ignored, the torque burden required to maintain the attitude of the camera 4 is evenly distributed to the first motor 8 and the second motor 10, making the torque burden the lightest.

[0038] In contrast, in a conventional gimbal device (not shown), the rotation axis of first motor 8 is located on axis AR perpendicular to optical axis A of camera 4, and the moment of force generated based on the movement of the center of gravity in the optical axis direction of the camera must be canceled out only by the torque generated by first motor 8. That is, in a conventional gimbal device, when the center of gravity of camera 4 is moved, in order to maintain the attitude of camera 4, it is necessary to generate a torque obtained by multiplying the weight of camera 4 by the movement distance of the center of gravity (corresponding to distance L in FIG. 3) by one motor (first motor 8).

[0039] For this reason, in a conventional gimbal device (not shown), when the center of gravity of the camera 4 is moved, the torque generated to maintain the attitude of the camera 4 is concentrated on one motor. As a result, it is necessary to adopt a large, powerful motor as the motor used to maintain the attitude of the camera 4. Furthermore, if the same motor as other motors is adopted as the motor used to maintain the attitude of the camera, there is little margin for the torque that can be generated by the motor used to maintain the attitude, and the responsiveness of the gimbal device decreases.

[0040] In the basic state of the gimbal device, the first connecting member 14 and the second connecting member 16, and the second connecting member 16 and the third connecting member 18 form a right angle with each other. This relationship changes when the gimbal device 2 deviates from the basic state. However, according to the gimbal device 2 of this embodiment, even when the basic state is deviated from, it is possible to reduce the output torque that each motor should generate.

[0041] In the above description, the camera mount, the first to third motors, and the first to third connecting members are assumed to be lightweight, and their masses are ignored. If the masses of these members cannot be ignored, the center of gravity of the entire members supported by each motor is configured to be located on the rotation axis of the motor, so that the camera 4 can be maintained in any posture without each motor actually outputting torque. That is, the center of gravity of the camera 4, the camera mount 6, and the first connecting member 14 is configured to be located on the first axis A1, the center of gravity of the camera 4, the camera mount 6, the first connecting member 14, the first motor 8, and the second connecting member 16 is configured to be located on the second axis A2, and the center of gravity of the camera 4, the camera mount 6, the first connecting member 14, the first motor 8, the second connecting member 16, the second motor 10, and the third connecting member 18 is configured to be located on the third axis A3. It is also possible to configure the gimbal device 2 so that the length of each connecting member can be adjusted to minimize the output torque of each motor required to maintain the basic state. In these cases, the center of gravity of the camera 4 itself is not necessarily located on the first to third axes.

[0042] Furthermore, even if the center of gravity of the camera 4 itself is not located on the first to third axes as described above, when the center of gravity of the camera 4 is moved by using the zoom function or the like, the output torque required for each motor to maintain the attitude of the camera 4 increases. However, even in such a case, as in the gimbal device 2 of this embodiment, by arranging the first axis A1 and the second axis A2 at an angle to the axis AR (the axis extending along the mounting surface 6a and parallel to the first plane P1) perpendicular to the optical axis A of the camera 4, the torque required to maintain the attitude of the camera 4 can be distributed to multiple motors, and the effect of reducing the torque burden of each motor can be obtained. In other words, even if the center of gravity of the camera 4 itself is not located on the first to third axes, the same effect as that of the gimbal device 2 described above can be obtained.

[0043] Next, the control of each motor in the gimbal device described in Patent Document 1 and the gimbal device 2 of this embodiment will be described with reference to FIGS. In the following description, the conventional gimbal device refers to a gimbal device in which, in the basic state, the axis AR (front edge of the camera mount) perpendicular to the optical axis A of the camera is parallel to the first axis A1, and the mounting surface of the camera mount is parallel to the first plane P1. The gimbal device described in Patent Document 1 refers to a gimbal device in which, in the basic state, the axis AR perpendicular to the optical axis A of the camera is oriented obliquely with respect to the first axis A1, and the mounting surface of the camera mount is parallel to the first plane P1. In contrast, in the gimbal device 2 of this embodiment, in the basic state, the axis AR perpendicular to the optical axis A of the camera is oriented obliquely with respect to the first axis A1, and the mounting surface 6a of the camera mount 6 is also oriented in a direction inclined with respect to the first plane P1.

[0044] Fig. 4 is an explanatory diagram that shows a typical relationship between the rotation shafts of the motors in a conventional gimbal device and the attitude angle of the camera. Fig. 5 is an explanatory diagram that shows a typical relationship between the rotation shafts of the motors in a gimbal device described in Patent Document 1 and the attitude angle of the camera. Fig. 6 is an explanatory diagram that shows a typical relationship between the rotation shafts of the motors in the gimbal device 2 of this embodiment and the attitude angle of the camera 4.

[0045] First, as shown in Fig. 4, in a conventional gimbal device, the rotational axis of the first motor 8' is oriented in the direction of the pitch axis y of the camera, the rotational axis of the second motor 10' is oriented in the direction of the roll axis x that coincides with the optical axis of the camera, and the rotational axis of the third motor 12' is oriented in the direction of the yaw axis z of the camera. Therefore, to pitch the camera by angle v, the first motor 8' is rotated by angle v. Similarly, to roll the camera by angle u, the second motor 10' is rotated by angle u, and to yaw by angle w, the third motor 12' is rotated by angle w.

[0046] The rotation matrix R corresponding to the rotation of angle u around the roll axis x, the rotation of angle v around the pitch axis y, and the rotation of angle w around the yaw axis z isx (u), R y (v), R z (w) can be expressed as the following formulas (1) to (3). TIFF2025051165000002.tif13150 TIFF2025051165000003.tif13150 TIFF2025051165000004.tif13150

[0047] Therefore, in a conventional gimbal device in which motors for the pitch axis, roll axis, and yaw axis are provided in that order from the camera side, the rotation matrix R that represents the rotation of the camera when rotations about the roll axis x, pitch axis y, and yaw axis z are performed simultaneously is gc can be calculated using formula (4). TIFF2025051165000005.tif6150

[0048] Next, in the gimbal device 2 described in Patent Document 1, as shown in FIG. 5, the optical axis A of the camera 4 is directed obliquely to the first axis A1 (pitch axis y) and the second axis A2 (roll axis x). Therefore, even if the first motor 8'' is simply rotated to rotate the camera around the first axis A1, the camera 4 does not perform a pure pitching motion (pitching motion that does not include rolling or yawing). In the gimbal device 2 described in Patent Document 1, when the camera 4 is caused to perform a pure pitching motion, in addition to the first motor 8'', the second motor 10'' and the third motor 12'' are also operated. Below, the control of each motor by the control unit when the camera 4 is attached rotated by an angle a around the yaw axis z will be described.

[0049] As described above, in the gimbal device described in Patent Document 1, as shown in Fig. 5, the optical axis A of the camera 4 is rotated by an angle a around the yaw axis z, and the optical axis A is inclined with respect to the roll axis x and the pitch axis y. Note that the absolute value of the angle a is less than 90°. The rotation matrix R that represents the attitude of the camera in this state is g is the rotation matrix R of angle a around the yaw axis z zThis can be obtained by multiplying (a) by equation (4) from the right side. That is, the rotation matrix R, which represents the camera orientation, is calculated by equation (5). g can be sought. TIFF2025051165000006.tif6150 TIFF2025051165000007.tif23170 TIFF2025051165000008.tif6150

[0050] In this way, in the gimbal device described in Patent Document 1, the optical axis A of the camera 4 is attached in a state rotated by an angle a around the yaw axis z. In such a gimbal device described in Patent Document 1, the rotation angles u, v, and w of each motor required to pitch the camera 4 by an angle b are expressed by a rotation matrix R pitch =R y Each element of (b) is transformed into the rotation matrix R calculated by the formula (5). g By equating each element of the formula (6), it can be calculated based on the formula (6). TIFF2025051165000009.tif13150

[0051] When this formula (6) is solved for the rotation angle u around the roll axis x (the rotation angle of the second motor 10″), You can get TIFF2025051165000010.tif6150.

[0052] Furthermore, when equation (6) is solved for the rotation angle v about the pitch axis y (the rotation angle of the first motor 8 ″), You can get TIFF2025051165000011.tif24150.

[0053] On the other hand, when equation (6) is solved for the rotation angle w about the yaw axis z (the rotation angle of the third motor 12″), You can get TIFF2025051165000012.tif10150.

[0054] As described above, in the gimbal device described in Patent Document 1, when pitching the camera 4 by angle b, the first motor 8'' is rotated by angle v calculated by formula (8), the second motor 10'' is rotated by angle u calculated by formula (7), and the third motor 12'' is rotated by angle w calculated by formula (9). In this manner, the gimbal device described in Patent Document 1 rotates the first to third motors as described above in order to cause the camera 4 to perform a pure pitching motion. For example, when an operation is performed by an operation unit provided on the grip unit to pitch the camera 4, the control unit calculates the rotation angle according to formulas (8), (7), and (9), and sends a control signal to each motor.

[0055] Next, the rotation angles u, v, and w of each motor required to roll the camera 4 by an angle c are expressed as the rotation matrix R roll =R x Each element of (c) is transformed into the rotation matrix R g By equating each element of the formula (10), it can be calculated based on the formula (10). TIFF2025051165000013.tif13150

[0056] When this formula (10) is solved for the rotation angle u around the roll axis x (the rotation angle of the second motor 10″), You can get TIFF2025051165000014.tif6150.

[0057] Next, solving equation (10) for the rotation angle v about the pitch axis y (the rotation angle of the first motor 8 ″) gives: You can get TIFF2025051165000015.tif23150.

[0058] Furthermore, when equation (10) is solved for the rotation angle w about the yaw axis z (the rotation angle of the third motor 12″), You can get TIFF2025051165000016.tif23150.

[0059] That is, in the gimbal device described in Patent Document 1, when the camera 4 is caused to perform a rolling motion by angle c, the first motor 8'' is rotated by angle v calculated by formula (12), the second motor 10'' is rotated by angle u calculated by formula (11), and the third motor 12'' is rotated by angle w calculated by formula (13). In this manner, the gimbal device described in Patent Document 1 rotates the first to third motors as described above in order to cause the camera 4 to perform a pure rolling motion. For example, when an operation is performed by an operation unit provided on the grip unit to cause the camera 4 to perform a rolling motion, the control unit calculates the rotation angle according to formulas (12), (11), and (13), and sends a control signal to each motor.

[0060] In the gimbal device described in Patent Document 1, when the camera 4 is caused to yaw at a predetermined angle, the control unit rotates only the third motor 12'' by that angle.

[0061] In this way, the control unit calculates the rotation angle of each motor required to orient the camera 4 in a desired direction by synthesizing the rotation matrix around each axis and performing coordinate transformation, and outputs a control signal to each motor. Specifically, the rotation matrix R of a basic gimbal device in which the rotation axes of each motor are oriented in the pitch axis, roll axis, and yaw axis directions, respectively, is gc by a rotation matrix that represents the inclination of the optical axis A of the camera 4, the rotation matrix R g Then, the orientation of the camera 4 is calculated. Furthermore, the rotation angles of the first motor 8'', the second motor 10'', and the third motor 12'' required to orient the camera 4 in a desired direction are calculated using the rotation matrix R g and a rotation matrix representing a desired rotation angle.

[0062] As shown in FIG. 4, in the conventional gimbal device, a first motor 8' for rotating the camera about a pitch axis y, a second motor 10' for rotating the camera about a roll axis x, and a third motor 12' for rotating the camera about a yaw axis z are arranged in that order from the camera's closest position, and the optical axis A of the camera is parallel to the roll axis x. In contrast to such conventional gimbal devices, in the gimbal device described in Patent Document 1, as shown in FIG. 5, the optical axis A of the camera 4 is tilted at an angle a so that it faces toward the first motor 8''. That is, in the gimbal device described in Patent Document 1, the optical axis A is tilted so that the angle between the optical axis A of the camera 4 and the roll axis x (the rotation axis of the second motor 10) is angle a in the horizontal plane.

[0063] Next, the operation of the gimbal device described in Patent Document 1 will be described with reference to FIGS. 7 to 9, and problems that arise in this gimbal device will be specifically described. Fig. 7 is a perspective view showing the gimbal device described in Patent Document 1 in a basic state. Fig. 8 is a perspective view showing the gimbal device described in Patent Document 1 in a state tilted 45 degrees forward. Fig. 9 is a perspective view showing the gimbal device described in Patent Document 1 in a state tilted 90 degrees forward. In the examples shown in Figs. 7 to 9, the angle a between the optical axis A of the camera 4 and the roll axis x is set to about 45 degrees.

[0064] In the basic state shown in FIG. 7, the grip 20'' is oriented vertically, and the optical axis A of the camera 4 is oriented horizontally. In this state, the first motor 8'' is rotated so that the first connecting member 14'' and the second connecting member 16'' form a substantially right angle when viewed from the direction of the rotation shaft of the first motor 8''. Also, the second motor 10'' is rotated so that the second connecting member 16'' and the third connecting member 18'' form a substantially right angle when viewed from the direction of the rotation shaft of the second motor 10''.

[0065] FIG. 8 shows a state in which the user tilts the grip portion 20″ forward by 45 degrees from the basic state shown in FIG. 7 (the grip portion 20″ is directed diagonally forward). In this state shown in FIG. 8, the first to third motors are controlled so that the optical axis A of the camera 4 is maintained in a substantially horizontal direction. That is, the first motor 8″ is rotated approximately 35.26 degrees from the state shown in FIG. 7, the second motor 10″ is rotated approximately 30 degrees, and the third motor 12″ is rotated approximately 9.73 degrees so that the optical axis A is maintained horizontal even when the grip portion 20″ is tilted diagonally forward. As a result, the angle between the first connecting member 14″ and the second connecting member 16″ is set to approximately 125.26 degrees, and the angle between the second connecting member 16″ and the third connecting member 18″ is set to approximately 120 degrees.

[0066] FIG. 9 shows a state in which the user has further tilted grip portion 20'' from the state shown in FIG. 8, tilting it forward by approximately 90 degrees (holding grip portion 20'' facing approximately horizontally). Even in the state shown in FIG. 9, the first to third motors are controlled so that the optical axis A of camera 4 is maintained approximately horizontal. Note that in normal use, it is considered that the gimbal device operates generally from the basic state shown in FIG. 7 through the state shown in FIG. 8 to the state in which grip portion 20'' is protruding forward as shown in FIG. 9.

[0067] In the state shown in FIG. 9, the first motor 8'' is rotated about 90 degrees from the state shown in FIG. 7, the second motor 10'' is rotated about 45 degrees, and the third motor 12'' is rotated about 45 degrees so that the optical axis A is maintained horizontal. As a result, the angle between the first connecting member 14'' and the second connecting member 16'' is set to about 180 degrees, and the angle between the second connecting member 16'' and the third connecting member 18'' is set to about 135 degrees. In other words, the second motor 10'' is rotated about 15 degrees from the state shown in FIG. 8, and the angle between the second connecting member 16'' and the third connecting member 18'' is set to about 135 degrees. Here, when the angle between the second connecting member 16'' and the third connecting member 18'' is set to about 180 degrees, the rotation axis of the first motor 8'' and the rotation axis of the third motor 12'' are aligned substantially on a straight line. In this state, there are effectively only two rotational axes about which the camera 4 can be rotated, and the gimbal device cannot orient the camera 4 in any direction. In other words, when the rotational axis of the first motor 8'' and the rotational axis of the third motor 12'' are aligned almost in a straight line, the gimbal device cannot pitch the camera 4.

[0068] This state in which the rotation axes of the two motors of the gimbal device are aligned in a nearly straight line is called "gimbal lock," and the gimbal device is unable to control the attitude of the camera. Even if the gimbal device does not reach the gimbal lock state, as it approaches the gimbal lock state, it becomes difficult for the gimbal device to effectively control the attitude, and control may become unstable. For this reason, it is preferable to operate the gimbal device in a state as far away from the gimbal lock state as possible.

[0069] The present inventors have found that in the gimbal device described in Patent Document 1, in which the optical axis A of the camera 4 and the roll axis x are set at an angle, there is a problem in that, in actual use, the gimbal device is prone to approaching a gimbal lock state as shown in FIG. 9, and control may become unstable during use. The present invention has solved this problem.

[0070] Next, the operation of the gimbal device 2 according to the first embodiment of the present invention will be described with reference to FIGS. As described above, in the gimbal device 2 according to the first embodiment of the present invention, in the basic state, the mounting surface 6a of the camera mount portion 6 is oriented in a direction inclined with respect to the first plane P1 including the first axis A1 and the second axis A2, and an axis extending along the mounting surface 6a and parallel to the first plane P1 (for example, the front edge 6b of the mounting surface 6a) is oriented obliquely with respect to the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane P1 (FIG. 1).

[0071] FIG. 10 is a perspective view showing the gimbal device 2 according to the first embodiment of the present invention in a state where the grip portion 20 is directed vertically upward. FIG. 11 is a perspective view showing the gimbal device 2 according to the first embodiment of the present invention in a state where it is tilted 45 degrees forward from the state shown in FIG. 10. FIG. 12 is a perspective view showing the gimbal device 2 according to the first embodiment of the present invention in a state where it is tilted 90 degrees forward from the state shown in FIG. 10. In the state shown in FIGS. 10 to 12, the first to third motors are controlled so that the optical axis A of the camera 4 is directed horizontally. In the first embodiment of the present invention shown in FIGS. 10 to 12, the angle between the mounting surface 6a of the camera mount portion 6 and the first plane P1 is about 45 degrees, and the front edge 6b of the mounting surface 6a is directed in a direction of about 45 degrees with respect to the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane P1.

[0072] In the state shown in FIG. 10, the grip portion 20 of the gimbal device 2 is directed vertically upward, and the optical axis A of the camera 4 is directed horizontally. In this state, the first motor 8 is rotated about 35.26 degrees with respect to the basic state, the second motor 10 is rotated about 30 degrees, and the third motor 12 is rotated about 9.73 degrees. As a result, the angle between the first connecting member 14 and the second connecting member 16 is about 54.74 degrees, and the angle between the second connecting member 16 and the third connecting member 18 is about 60 degrees. Thus, in the gimbal device 2 of this embodiment, when the grip portion 20 (third axis A3) is directed vertically upward and the optical axis A of the camera 4 is directed horizontally, the angle between the first connecting member 14 and the second connecting member 16 and the angle between the second connecting member 16 and the third connecting member 18 are both less than 90 degrees. Preferably, the first, second and third motors are controlled so that the angle between the second connecting member 16 and the third connecting member 18 is about 35 degrees to about 85 degrees when the third axis A3 is oriented vertically and the optical axis A of the camera 4 is oriented horizontally. The specific calculation of the angle of each motor will be described later.

[0073] FIG. 11 shows a state in which the user tilts the grip portion 20 from the state shown in FIG. 10 toward the subject by about 45 degrees forward (the grip portion 20 is directed diagonally forward). Even in the state shown in FIG. 11, the first to third motors are controlled so that the optical axis A of the camera 4 faces substantially horizontally. That is, the first motor 8 is rotated about 35.26 degrees from the state shown in FIG. 10, the second motor 10 is rotated about 30 degrees, and the third motor 12 is rotated about 9.73 degrees so that the optical axis A is maintained horizontally even in the state shown in FIG. 11. As a result, the angle between the first connecting member 14 and the second connecting member 16 is set to about 90 degrees, and the angle between the second connecting member 16 and the third connecting member 18 is also set to about 90 degrees. That is, the gimbal device 2 of this embodiment is in a basic state when the grip portion 20 (third axis A3) is tilted forward by about 45 degrees and the mounting surface 6a faces horizontally. Preferably, the first, second and third motors are controlled so that when the third axis A3 is tilted at a predetermined angle between approximately 15 degrees and approximately 75 degrees in a vertical plane, the second connecting member 16 and the third connecting member 18 form a right angle (basic state).

[0074] FIG. 12 shows a state where the user further tilts the grip portion 20 from the basic state shown in FIG. 11 to tilt it forward by about 90 degrees (the grip portion 20 is oriented in a substantially horizontal direction). Even in the state shown in FIG. 12, the first to third motors are controlled so that the optical axis A of the camera 4 faces in a substantially horizontal direction. That is, the first motor 8 is rotated about 35.26 degrees from the state shown in FIG. 11, the second motor 10 is rotated about 30 degrees, and the third motor 12 is rotated about 9.73 degrees so that the optical axis A is maintained horizontal even in the state shown in FIG. 12. As a result, the angle between the first connecting member 14 and the second connecting member 16 is set to about 125.26 degrees, and the angle between the second connecting member 16 and the third connecting member 18 is also set to about 120 degrees.

[0075] In this way, when the grip part 20 is tilted forward while maintaining the optical axis A of the camera 4 horizontal from the state shown in Fig. 10 to the state shown in Fig. 12, the angle between the second connecting member 16 and the third connecting member 18 increases. Then, when the angle between the second connecting member 16 and the third connecting member 18 becomes 180 degrees (or 0 degrees), a gimbal lock state is entered. Furthermore, when the angle between the second connecting member 16 and the third connecting member 18 approaches 180 degrees, it becomes difficult to control the attitude of the camera 4, and the control becomes unstable.

[0076] In the gimbal device 2 of this embodiment, when the grip part 20 is oriented vertically upward as shown in FIG. 10, the angle between the second connecting member 16 and the third connecting member 18 is set to about 60 degrees. Therefore, even when the grip part 20 is tilted forward by 90 degrees as shown in FIG. 12, the angle between the second connecting member 16 and the third connecting member 18 is suppressed to about 120 degrees or less, and a state with sufficient margin against gimbal lock is maintained. As a result, in the gimbal device 2 of this embodiment, even in the state shown in FIG. 12, the control does not become unstable and the camera 4 can be pitched by the gimbal device 2. In this way, according to the gimbal device 2 of this embodiment, the basic state, which is the furthest from the gimbal lock state, is reached at the midpoint (the state shown in FIG. 11) of the angular range of the grip part 20 where normal use is expected. As a result, a state in which gimbal lock is unlikely to occur is maintained throughout the angular range of the grip part 20 where normal use is expected, and the attitude of the camera 4 can be stably controlled.

[0077] The gimbal device 2 of this embodiment can also be used with the grip portion 20 facing further downward than the state shown in Figure 12, and can also be used with the grip portion 20 facing approximately 45 degrees downward from the horizontal plane.

[0078] Next, control of each motor in the gimbal device 2 according to the first embodiment of the present invention will be described. In the gimbal device 2 according to the first embodiment of the present invention, the rotation angle of each motor required to orient the attached camera 4 in a predetermined direction can be found as follows. First, in the gimbal device 2 of this embodiment, the optical axis A of the camera 4 is rotated around the first axis A1 by an angle e (45 degrees in this embodiment) and then rotated around the third axis A3 by an angle a (45 degrees in this embodiment) compared to the conventional gimbal device. Then, a rotation matrix R representing a state in which the grip portion 20 of the gimbal device 2 of this embodiment is tilted by an angle f in a vertical plane is calculated. gP is the rotation matrix of the conventional gimbal device in R gc (Formula (4)) It can be expressed as TIFF2025051165000017.tif6150.

[0079] Here, the rotation angles of each motor required to orient the camera 4 attached to the gimbal device 2 of this embodiment to face forward (a state in which the optical axis A faces horizontally within a vertical plane in which the grip portion 20 is tilted) can be found by equating each element of the rotation matrix E (unit matrix) representing the forward direction with each element of the rotation matrix of equation (14). That is, it can be found by solving the following equation for the rotation angles u, v, and w of each motor. TIFF2025051165000018.tif6150

[0080] First, add R to each side of equation (15) from the left. y (-f) from the right y (-e)·R z By multiplying by (-a), TIFF2025051165000019.tif12150. Equation (16) can be rearranged to give the following result. TIFF2025051165000020.tif6150

[0081] From equations (2), (3), and (4), each component of equation (17) can be expressed as follows: TIFF2025051165000021.tif26170Focusing on the components in the third row and second column of equation (18), the rotation angle u of the second motor 10 is given by The resulting file is TIFF2025051165000022.tif6150.

[0082] Furthermore, when we look at the components in the third row and first column of equation (18), the rotation angle v of the first motor 8 is given by The resulting file is TIFF2025051165000023.tif23150.

[0083] Furthermore, when attention is paid to the components in the first row and second column of equation (18), the rotation angle w of the third motor 12 is given by The resulting file is TIFF2025051165000024.tif21150.

[0084] In this way, when the grip portion 20 of the gimbal device 2 of the first embodiment of the present invention is tilted by angle f, the rotation angle of each motor required to orient the optical axis A of the camera 4 in the horizontal direction can be calculated using formulas (19), (20), and (21). That is, the rotation angle of each motor in the state illustrated in Fig. 9 can be calculated by substituting a = 45°, e = 45°, and f = 0° into these formulas. Moreover, when calculating the rotation angle of each motor in the state illustrated in Figs. 10 and 11, the value of f should be changed to 45 degrees and 90 degrees, respectively.

[0085] Next, the rotation angle of each motor required to rotate the camera 4 attached to the gimbal device 2 of this embodiment in a predetermined direction is calculated by multiplying each element of the rotation matrix representing the rotation by the rotation matrix R in Equation (14). gP That is, the rotation angle of each motor required to pitch the camera 4 by the angle b can be calculated by the rotation matrix R y (v) Rotation matrix R with angle b substituted y This can be obtained by equating (b) and (14) to get (22). TIFF2025051165000025.tif6150

[0086] By solving equation (22) for the rotation angle u of the second motor 10, the following equation (23) is obtained. TIFF2025051165000026.tif6150 Furthermore, by solving the formula (22) for the rotation angle v of the first motor 8, the following formula (24) is obtained. TIFF2025051165000027.tif23150Then, by solving equation (22) for the rotation angle w of the third motor 12, the following equation (25) is obtained. TIFF2025051165000028.tif21150

[0087] In this way, the rotation angle of each motor required to pitch the camera 4 by angle b while holding the gimbal device 2 with the gripper 20 tilted at angle f can be calculated by formulas (23), (24), and (25). That is, to pitch the camera 4 by angle b, the first motor 8 is rotated by angle v calculated by formula (24), the second motor 10 is rotated by angle u calculated by formula (23), and the third motor 12 is rotated by angle w calculated by formula (25). In this way, in the gimbal device 2 of this embodiment, in order to cause the camera 4 to perform a pure pitching motion, the first to third motors must be rotated as described above. For example, when an operation is performed by the operation unit 20a provided on the gripper 20 to pitch the camera 4, the control unit 20b calculates the rotation angle according to formulas (23), (24), and (25) and sends a control signal to each motor.

[0088] Next, in the gimbal device 2 of this embodiment, the rotation angles u, v, and w of each motor required to roll the camera 4 by an angle c are calculated by the rotation matrix R x Rotation matrix R with angle c substituted into (u) x (c) can be obtained by equating equation (14) with equation (26). TIFF2025051165000029.tif6150

[0089] When this equation (26) is solved for the rotation angle u around the roll axis x (the rotation angle of the second motor 10), You can get TIFF2025051165000030.tif6150.

[0090] Furthermore, when equation (26) is solved for the rotation angle v about the pitch axis y (the rotation angle of the first motor 8), You can get TIFF2025051165000031.tif33150.

[0091] On the other hand, when equation (26) is solved for the rotation angle w about the yaw axis z (the rotation angle of the third motor 12), You can get TIFF2025051165000032.tif33150.

[0092] As described above, in the gimbal device 2 of this embodiment, when the camera 4 is caused to perform a rolling motion by angle c, the first motor 8 is rotated by angle v calculated by formula (28), the second motor 10 is rotated by angle u calculated by formula (27), and the third motor 12 is rotated by angle w calculated by formula (29). Thus, in the gimbal device 2 of this embodiment as well, in order to cause the camera 4 to perform a pure rolling motion, the first to third motors must be rotated as described above. For example, when an operation is performed by the operation unit 20a provided on the grip unit 20 to cause the camera 4 to perform a rolling motion, the control unit 20b calculates the rotation angle according to formulas (27), (28), and (29) and sends a control signal to each motor.

[0093] Next, in the gimbal device 2 of this embodiment, the rotation angles u, v, and w of the motors required to yaw the camera 4 by an angle d are calculated by the rotation matrix R z Rotation matrix R with angle d substituted into (w) z (d) can be obtained by equating equation (14) with equation (30). TIFF2025051165000033.tif6150

[0094] When this equation (30) is solved for the rotation angle u around the roll axis x (the rotation angle of the second motor 10), You can get TIFF2025051165000034.tif6150.

[0095] Furthermore, when equation (30) is solved for the rotation angle v about the pitch axis y (the rotation angle of the first motor 8), You can get TIFF2025051165000035.tif33150.

[0096] On the other hand, when equation (30) is solved for the rotation angle w about the yaw axis z (the rotation angle of the third motor 12), You can get TIFF2025051165000036.tif33150.

[0097] In this way, in the gimbal device 2 of this embodiment, when the camera 4 is caused to yaw by angle d, the first motor 8 is rotated by angle v calculated by formula (32), the second motor 10 is rotated by angle u calculated by formula (31), and the third motor 12 is rotated by angle w calculated by formula (33). In this way, in the gimbal device 2 of this embodiment, in order to cause the camera 4 to perform a pure yawing motion, the first to third motors need to be rotated as described above. For example, when an operation is performed by the operation unit 20a provided on the grip unit 20 to cause the camera 4 to yaw, the control unit 20b calculates the rotation angle according to formulas (31), (32), and (33), and sends a control signal to each motor.

[0098] By controlling the first to third motors as described above, the optical axis A of the camera 4 attached to the gimbal device 2 according to the first embodiment of the present invention can be directed in a desired direction.

[0099] According to the gimbal device 2 of the first embodiment of the present invention, the front edge 4b, which is an axis parallel to the first plane P1 extending along the mounting surface 6a, is obliquely oriented with respect to the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane P1. Therefore, the torque for canceling the moment generated by the movement of the center of gravity G1 of the camera 4 is not concentrated in one motor, but the canceling torque is shared by multiple motors. This increases the margin of output of each motor, making it possible to respond to the movement of the center of gravity of the camera 4 with a motor with a lower output.

[0100] Furthermore, according to the gimbal device 2 of this embodiment, the mounting surface 6a of the camera mount portion 6 is oriented in a direction inclined with respect to the first plane P1 including the first axis A1 and the second axis A2 when the first connecting member 14 and the second connecting member 16 form a right angle. Therefore, the optical axis A of the camera 4 attached to the mounting surface 6a is oriented in the horizontal direction when the grip portion 20 is tilted. As a result, when the grip portion 20 is tilted, the gimbal device 2 can be kept away from gimbal lock, and the occurrence of gimbal lock in the normal range of use of the gimbal device 2 can be suppressed.

[0101] Furthermore, according to the gimbal device 2 of this embodiment, when the first connecting member 14 and the second connecting member 16 form a right angle, the angle that the front edge 6b of the mounting surface 6a, which extends along the mounting surface 6a and is oriented parallel to the first plane P1, makes with the first axis A1 is configured to be approximately 45 degrees when viewed from a direction perpendicular to the first plane P1. Therefore, when the center of gravity of the camera 4 is moved in the direction of the optical axis A, the torque required to maintain the attitude of the camera 4 can be shared approximately equally between the first motor 8 and the second motor 10, thereby reducing the burden on each motor.

[0102] Furthermore, according to the gimbal device 2 of this embodiment, when the first connecting member 14 and the second connecting member 16 form a right angle, the angle between the attachment surface 6a of the camera mount portion 6 and the first plane P1 is configured to be approximately 45 degrees. Therefore, the gimbal device 2 is in the basic state when the grip portion 20 is tilted approximately 45 degrees, and is maintained in a state away from gimbal lock over a wide range of the actual use area on both sides, allowing the attitude of the camera 4 to be stably controlled.

[0103] Furthermore, according to the gimbal device 2 of this embodiment, the control unit 20b controls the first to third motors so that the second connecting member 16 and the third connecting member 18 form a right angle when the third axis A3 is tilted by approximately 45 degrees and the mounting surface 6a is oriented horizontally. Therefore, even when the third axis A3 is brought closer to horizontal or closer to vertical from a state in which the third axis A3 is tilted by approximately 45 degrees, the angle formed by the second connecting member 16 and the third connecting member 18 is maintained at an angle relatively close to a right angle, making it possible to prevent the occurrence of gimbal lock in the actual usage range of the gimbal device 2.

[0104] Furthermore, according to the gimbal device 2 of this embodiment, the control unit 20b controls the first to third motors so that the angle between the second connecting member 16 and the third connecting member 18 is smaller than 90 degrees when the third axis A3 is oriented vertically and the mounting surface 6a is oriented horizontally. Therefore, even if the third axis A3 is tilted forward from a state in which the third axis A3 is oriented vertically, the angle between the second connecting member 16 and the third connecting member 18 is kept relatively small, making it possible to prevent gimbal lock from occurring in the actual use range of the gimbal device 2.

[0105] Next, a gimbal device according to a second embodiment of the present invention will be described with reference to FIGS. As described above, the gimbal device according to the first embodiment of the present invention is mainly intended to be used between a state in which the grip part 20 faces vertically upward and a state in which it faces horizontally. It is also possible to use the gimbal device with the grip part 20 facing downward below the horizontal plane. However, in such a state, the first motor 8, the second connecting member 16, etc. are likely to be in the field of view of the camera 4, making it difficult to use. This phenomenon also occurs in conventional gimbal devices.

[0106] In contrast, the gimbal device according to the second embodiment of the present invention is intended to be used primarily between a state in which the grip is oriented vertically downward and a state in which it is oriented horizontally. That is, the gimbal device of this embodiment is suitable for use with a camera suspended downward. Fig. 13 is a perspective view showing the basic state of the gimbal device according to the second embodiment of the present invention. Fig. 14 is a perspective view showing the gimbal device according to the second embodiment of the present invention with the grip oriented vertically downward and the optical axis of the camera oriented horizontally.

[0107] 13, a gimbal device 102 according to the second embodiment of the present invention has a camera mount 106 for mounting a camera 4, a first motor 108 for rotating the camera mount 106 about a first axis A1, a second motor 110 for rotating the camera mount 106 about a second axis A2, and a third motor 112 for rotating the camera mount 106 about a third axis A3. The gimbal device 102 further has a first connecting member 114 for connecting the camera mount 106 and the first motor 108, a second connecting member 116 for connecting the first motor 108 and the second motor 110, a third connecting member 118 for connecting the second motor 110 and the third motor 112, and a gripping portion 120 which is a support portion to be gripped by the photographer.

[0108] 13 shows the basic state of the gimbal device 102 (a state in which the first connecting member 114 and the second connecting member 116 form a right angle, and the second connecting member 116 and the third connecting member 118 form a right angle). In this basic state, the first axis A1, the second axis A2, and the third axis A3 are oriented in different directions and are perpendicular to each other. That is, in the basic state shown in FIG. 13, when the grip portion 120 is oriented to extend vertically, the first connecting member 114 is oriented to extend in a vertical plane, the second connecting member 116 is oriented to extend in a horizontal plane, and the third connecting member 118 is oriented to extend in a vertical plane.

[0109] The camera mount section 106 has a flat mounting surface 106a for fixing the camera 4. Furthermore, in this embodiment, in the basic state shown in FIG. 13, the mounting surface 106a is configured as a rectangular plane oriented in a direction inclined with respect to a first plane P1 including the first axis line A1 and the second axis line A2. In this embodiment, the mounting surface 106a of the camera mount section 106 is configured to form an angle of about 45 degrees with respect to the first plane P1. Preferably, the mounting surface 106a is configured to form an angle of about 15 degrees to about 75 degrees with respect to the first plane P1, and more preferably, the mounting surface 106a is configured to form an angle of about 30 degrees to about 60 degrees with respect to the first plane P1.

[0110] Furthermore, the front edge 106b of the mounting surface 106a is oriented obliquely (non-parallel and non-perpendicular) to the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane P1. In other words, an axis parallel to the first plane P1 extending along the mounting surface 106a, such as the front edge 106b, is oriented obliquely to the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane. In this embodiment, the front edge 106b of the mounting surface 106a is configured to form an angle of approximately 45 degrees with respect to each of the first axis A1 and the second axis A2 when viewed from a direction perpendicular to the first plane P1. Preferably, when viewed in a direction perpendicular to the first plane P1, the front edge 106b of the mounting surface 106a is configured to form an angle of about 15 degrees to about 75 degrees with respect to the first axis A1, and more preferably, to form an angle of about 30 degrees to about 60 degrees.

[0111] Moreover, the camera mount section 106 is configured to mount the camera 4 such that its front edge 106b is parallel to the front edge 4b ​​of the housing of the camera 4. As a result, the camera 4 is mounted to the camera mount section 106 such that the optical axis A is perpendicular to the front edge 106b of the camera mount section 106 when viewed from a direction perpendicular to the mounting surface 106a. Furthermore, in this state, the mounting surface 106a of the camera mount section 106 and the optical axis A of the camera 4 are oriented parallel to each other. Therefore, in the basic state shown in FIG. 13, when the grip section 120 is oriented to extend vertically downward, the optical axis A of the camera 4 is oriented obliquely downward with respect to the horizontal plane.

[0112] In this manner, when the grip portion 120 of the gimbal device 102 of this embodiment in the basic state is oriented vertically downward, the optical axis A of the camera 4 attached to the camera mount portion 106 is oriented in a diagonally downward direction of approximately 45 degrees. Therefore, in order to orient the optical axis A of the camera 4 attached to the gimbal device 102 in the basic state shown in Fig. 13 in the horizontal direction, it is necessary to orient the grip portion 120 in a direction diagonally downward and forward of approximately 45 degrees so that the optical axis A is rotated within a vertical plane including the optical axis A. In other words, when the grip portion 120 of the gimbal device 102 of this embodiment is oriented diagonally downward at approximately 45 degrees, the gimbal device 102 is in a basic state in which the first connecting member 114 and the second connecting member 116 form a right angle, and the second connecting member 116 and the third connecting member 118 form a right angle.

[0113] Then, when the grip 120 is oriented vertically downward while maintaining the optical axis A of the camera 4 in the horizontal direction, the gimbal device 102 is in the state shown in Fig. 14. In the state shown in Fig. 14, the angle between the first connecting member 114 and the second connecting member 116 is approximately 54.74 degrees, and the angle between the second connecting member 116 and the third connecting member 118 is approximately 60 degrees. Also, as shown in Fig. 14, in the gimbal device 102 of this embodiment, when the grip 120 is oriented vertically downward and the optical axis A of the camera 4 is oriented horizontally, the second connecting member 116 extends rearward, and the second connecting member 116 does not enter the field of view of the camera 4, making it easy to use.

[0114] Furthermore, when the gripping portion 120 is oriented horizontally while maintaining the optical axis A of the camera 4 horizontally (not shown), the angle between the first connecting member 114 and the second connecting member 116 is approximately 125.26 degrees, and the angle between the second connecting member 116 and the third connecting member 118 is also approximately 120 degrees.

[0115] In this way, the gimbal device 102 of this embodiment is maintained in a state sufficiently away from the gimbal lock state from at least a state in which the gripper 120 is facing vertically downward to a state in which it is facing horizontally, and can stably control the attitude of the camera 4. Furthermore, with the gimbal device 102 of this embodiment, the attitude of the camera 4 can be controlled even in a state in which the gripper 120 is facing diagonally upward up to about 45 degrees. Note that specific angles of the first motor 108, the second motor 110, and the third motor 112 in the control of the gimbal device 102 of this embodiment can be calculated using a rotation matrix, similar to the gimbal device 2 of the first embodiment of the present invention.

[0116] Although the embodiments of the present invention have been described above, various modifications can be made to the above-described embodiments. In particular, in the above-described embodiments of the present invention, the mounting surface of the camera mount is configured to be inclined at a predetermined angle with respect to the first plane P1, but this inclination angle can also be configured to be changeable. For example, the angle of the mounting surface of the camera mount can be configured to be changeable between the angle in the first embodiment of the present invention shown in FIG. 1 and the angle in the second embodiment of the present invention shown in FIG. 13. [Explanation of symbols]

[0117] 1 Camera System 2 Gimbal device 4. Camera 4a Lens barrel 4b Leading edge 6 Camera mount 6a Mounting surface 6b Leading edge 8 First Motor 10 Second motor 12 3rd motor 14 First connecting member 16 Second connecting member 18 Third connecting member 20 Gripping part (support part) 20a Control unit 20b Control section 102 Gimbal device 106 Camera mount 106a Mounting surface 106b Leading edge 108 First Motor 110 Second Motor 112 3rd motor 114 First connecting member 116 Second connecting member 118 Third connecting member 120 Gripping part

Claims

1. A gimbal device for use with a camera attached, a camera mount portion having an attachment surface for fixing the optical axis of the camera in a predetermined direction; a first motor that rotates the camera mount unit about a first axis; a first connecting member that connects the camera mount portion and the first motor; a second motor that rotates the camera mount about a second axis; a second connecting member connecting the first motor and the second motor; a third motor that rotates the camera mount unit about a third axis; a third connecting member connecting the second motor and the third motor; a support portion connected to the third motor and configured to support the gimbal device; a control unit that controls the first, second, and third motors; having a gimbal device characterized in that, when the first connecting member and the second connecting member form a right angle, the mounting surface of the camera mount portion is oriented in a direction inclined with respect to a first plane including the first axis and the second axis, and an axis extending along the mounting surface and parallel to the first plane is oriented obliquely with respect to the first axis and the second axis when viewed from a direction perpendicular to the first plane.

2. 2. The gimbal device according to claim 1, wherein, when the first connecting member and the second connecting member form a right angle, an angle between an axis extending along the mounting surface and parallel to the first plane and the first axis is 15 degrees to 75 degrees when viewed from a direction perpendicular to the first plane.

3. 3. The gimbal device according to claim 1, wherein when the first connecting member and the second connecting member form a right angle, the angle between the attachment surface of the camera mount portion and the first plane is 15 degrees to 75 degrees.

4. 3. The gimbal device according to claim 1 or 2, wherein the control unit controls the first, second, and third motors so that, when the third axis is inclined at a predetermined angle and the mounting surface is oriented horizontally, the second connecting member and the third connecting member form a right angle.

5. 3. The gimbal device according to claim 1 or 2, wherein the control unit controls the first, second, and third motors so that an angle between the second connecting member and the third connecting member is smaller than 90 degrees when the third axis is oriented vertically and the mounting surface is oriented horizontally.

6. 3. The gimbal device according to claim 1, wherein a front edge of the attachment surface of the camera mount portion is configured to extend parallel to the first plane along the attachment surface.

7. A camera system including a gimbal device for supporting a camera, The gimbal device according to claim 1 or 2, A camera attached to the gimbal device, A camera system comprising:

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