JPH08145682A - Gimbal mechanism - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a gimbal mechanism that can be spatially stabilized by a large torque without restricting the space in which a load can be mounted. [Configuration] Gimbal support 23a, 23b of the base 24
Is provided with a gimbal frame 25 rotatably around the X-axis, and a mounting base 26 is rotatably mounted around the Y-axis orthogonal to the X-axis on the gimbal frame 25. One end of the mounting base 26 is ferromagnetic. A yoke 29 made of material is provided. This yoke 29
Permanent magnet pieces 28a and 28b are provided opposite to each other at both ends, and an electromagnetic coil 27 supported by the base 24 is inserted between the permanent magnet pieces 28a and 28b with a slight gap. The rotation angle of the mount 26 around the X axis is detected by the X axis angular velocity sensor 30, and the rotation angle of the mount 26 around the Y axis is detected by the Y axis angular velocity sensor 31. The control unit 32 controls the energization of the electromagnetic coil 27 based on the outputs of the angular velocity sensors 30 and 31, and suppresses the vibration of the mounted object mounted on the mounting base 26 with a large torque.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gimbal mechanism, such as a space stabilizer, which is equipped with a gyro sensor, a video camera, and the like, and prevents movement of the posture due to disturbance.

[0002]

2. Description of the Related Art FIG. 5 is a perspective view showing a space stabilizer 1 using a typical prior art gimbal mechanism. In this space stabilizer 1, a pair of gimbal supports 3 and 4 are fixed to a base 2, and a gimbal frame 5 is rotatably supported around the X axis at the free ends of the gimbal supports 3 and 4.
A mounting base 6 is supported on the gimbal frame 5 so as to be rotatable around a Y axis orthogonal to the X axis. One of the gimbal supports 3 is provided with an X-axis angle detector 7 for detecting the rotation angle of the gimbal frame 5 about the X-axis, and the gimbal frame 5 is provided with Y for detecting the rotation angle of the mount 6 about the Y-axis. A shaft angle detector 8 is provided. On the other gimbal support 4,
An X-axis torque generator 9 for rotating the gimbal frame 5 around the X-axis is provided. A Y-axis torque generator 10 for rotating the mount 6 around the Y-axis is provided on one side of the mount 6 opposite to the X-axis angle detector 8. The mounting base 6 has supporting surfaces 11a, 11b, 11c called three platforms in this example, and various supporting objects such as a gyro sensor and a video camera are mounted on these supporting surfaces 11a to 11c. When a disturbance element such as wind or vibration is added to the mounted object and the posture is disturbed to cause sway, the gyro sensor placed on the platform of the mount 6 on which the mounted object is mounted causes an angular velocity around the X axis and the Y axis. To detect. This angular velocity signal is fed back, and a torque generation command for stopping the vibration caused by the disturbance is given to each of the torque generators 9 and 10, so that the mounted object can be spatially stabilized. Such prior art is, for example, "Matsushita Technique Vol 34 N".
o. 6/1988 ", pages 662-668.

[0003]

In such prior art, when a large disturbance torque is generated when a disturbance element is applied, in order to spatially stabilize the mounted object, the torque generators 9 and 10 are required. Although it is necessary to increase the output torque of the above, the torque generators 9 and 10 become larger as the output torque increases, and when the maximum size is limited, on the support surfaces 11a to 11c of the mounting base 6. The torque generator occupies a space that can be mounted on the vehicle, which is not convenient.

Accordingly, it is an object of the present invention to provide a gimbal mechanism which can be spatially stabilized by a large torque without restricting the space in which the load can be mounted.

[0005]

According to the present invention, there is provided a base, a gimbal frame rotatably supported on the base about a first axis, and a second gimbal frame orthogonal to the first axis. Of the mounting base, which is rotatably supported around the axis of, and on which a load to be spatially stabilized is mounted, and the base, about the intersection point with respect to a radius line passing through the intersection point of the first and second axes. And a flat electromagnetic coil having a spherical center as a spherical center, and a ferromagnetic material provided on the mounting base and having a magnetic pole at both ends facing the both sides in the thickness direction of the electromagnetic coil.
And a current-carrying current to the electromagnetic coil, which serves as a torque generating means of the gimbal mechanism. In the present invention, the electromagnetic coil includes a first winding that generates a torque around a first axis, a plane parallel to the first winding, and a winding direction perpendicular to the first winding. Second
And a second winding that generates torque about the axis of the.

[0006]

According to the present invention, a gimbal frame is rotatably supported on a base about a first axis, and a mounting base is mounted on the gimbal frame about a second axis orthogonal to the first axis. Is rotatably supported by. On the mount, mounted objects such as a video camera and various gyro sensors are mounted. The base is also provided with an electromagnetic coil on a spherical surface with a radius of a line passing through the intersection of the first and second axes as the center of the intersection. Further, the mounting base is provided with yokes having magnetic poles facing each other on both sides in the thickness direction of the electromagnetic coil. The yoke has a substantially C shape and is made of a ferromagnetic material. Therefore, it is possible to penetrate the electromagnetic coil and form a loop-shaped magnetic field in the substantially C-shaped yoke. Since the magnetic field penetrates the electromagnetic coil, a current proportional to the current and the magnetic flux density is generated between the electromagnetic coil and the magnetic pole portion of the yoke according to Fleming's left-hand rule by passing a current through the electromagnetic coil. In the present invention, the electromagnetic coil is fixed to the base,
Since the yoke is fixed to the rotatable mount, this thrust acts on the rotary shaft as a torque proportional to the shortest distance between the magnetic pole and the rotary shaft. The yoke does not have to be fixed directly to the rotating shaft, but can be installed at any position and can be connected to the mounting base by some means, so that the dimension between the rotating shaft and the magnetic poles is relatively easy. It is possible to increase the torque, and thus a large rotational torque can be easily generated.

As described above, the torque generating means generates the torque at a position radially outward from the rotation center of the gimbal frame and the mounting base, so that the X-shape can be achieved without increasing the size of the structure.
A large torque can be obtained around the axis and the Y axis. Moreover, since the torque generating means can be provided in the space on one side with respect to the one plane including the first and second axes, there is no fear of occupying a space in which a load can be mounted, and thus a large mounting space can be provided. Can be secured.

According to the invention, since the electromagnetic coil is composed of the first winding and the second winding whose winding directions are orthogonal to each other, the energizing amount of each winding is selectively controlled by the control means. By controlling the torque, it is possible to generate the torque around the first and second axes, whereby the structure can be downsized and a large torque can be generated.

[0009]

1 is a perspective view showing a space stabilizer 21 using a gimbal mechanism according to an embodiment of the present invention. The space stabilizer 1 according to the present embodiment basically includes a base 24 to which a pair of gimbal supports 23a and 23b are fixed on one surface of a base 22, and a base 24 around an X axis which is a first axis. Gimbal frame 25 rotatably supported, and gimbal frame 25
A mount 26, which is rotatably supported around a Y-axis that is a second axis perpendicular to the X-axis, and on which a load to be spatially stabilized is mounted, and a base 24 for the X-axis and the Y-axis. A flat electromagnetic coil 27 provided on a spherical surface with P substantially spherical with respect to a radius line passing through the intersection point P, and provided on the mount 26 and made of a ferromagnetic material such as low carbon steel,
An approximately C-shaped yoke 29 to which a pair of permanent magnet pieces 28a and 28b having magnetic poles magnetized in the thickness direction of the electromagnetic coil 27 are fixed to both ends, and an X-axis of the gimbal frame 25 provided on the mount 26. An X-axis angular velocity sensor 30, which is a first rotational angle detector that detects the rotational angular velocity around, and a second rotational angle detector that is also provided on the mounting base 26 and that detects the rotational angular velocity around the Y-axis of the mounting base 26. A certain Y-axis angular velocity sensor 3
1, X-axis angular velocity sensor 30 and Y-axis angular velocity sensor 3
The excitation current to the electromagnetic coil 27 is controlled on the basis of each output from 1 to generate a magnetic force so that each rotation angular velocity of the mounting base 26 becomes a predetermined optimum value, for example, 0 even if the base sways. And a control means 33 for controlling.

The aforementioned electromagnetic coil 27 and each permanent magnet piece 2
The torque generating means 32 is configured to include the yoke 29 having 8a and 28b. The base 24 and the gimbal frame 25
The mount 26 is made of substantially the same material as the yoke 29, for example, low carbon steel.

FIG. 2 is a partial sectional view showing a specific structure of the space stabilizer 21. The mounting base 26 is connected to the inverted U-shaped convex portion 36 and the both ends of the convex portion 36 by being bent at a substantially right angle and connected to each other and extending outwardly on both sides (left and right directions in FIG. 2).
And two horizontal portions 37, 38. The convex portion 36 is
A top plate 39 substantially parallel to each horizontal portion 37, 38 and a top plate 3
Bend at a substantially right angle from both ends of 9 and fall 2
It has two side plates 40 and 41. Bearings 42 and 43 are fitted into the side plates 40 and 41, respectively.
Pin bolts 44 and 45 are rotatably supported around Y axis by 2 and 43. The gimbal frame 25 is fixed to the ends of the pin bolts 44, 45 that project inward from the bearings 42, 43 by nuts 46, 47. In this way, the mount 26 is rotatably connected to the gimbal frame 25 about the Y axis.

The yoke 29 is fixed to the one horizontal portion 38 of the mount 26, and the X-axis angular velocity sensor 30 and the Y-axis angular velocity sensor 31 are provided on the other horizontal portion 37 (in FIG. 2). (Not shown). Angular velocity sensor 3
As an example, 0 and 31 are two thin strip-shaped piezoelectric bimorphs, one of which is a driving element, and the other of which is a sensing element. A voltage is applied to the driving element, and the driving element vibrates in parallel with its surface. When the drive element and the detection element are rotated about axes parallel to the longitudinal direction, the Coriolis force generated in proportion to the rotational angular velocity causes the detection element to bend in a direction perpendicular to the surface thereof. A so-called sound-difference-type angular velocity sensor configured to detect the rotational angular velocity by extracting the deflection amount as an electric signal can be used.

The gimbal frame 25 includes the bearings 4 described above.
2, 43, each pin bolt 44, 45 and each nut 4
6 and 47 are connected to the gimbal supports 23a and 23b of the base 24 by the same structure so as to be rotatable about the X axis.

As described above, the yoke 29 is attached to the one horizontal portion 38, the attachment portion 48, the spherical inner wall portion 49 continuous with the attachment portion 48 and having the intersection point P as the center, and the inner wall portion 49. It has a spherical outer wall portion 51 continuous with the connecting portion 50 and having the intersection P as a center. The inner wall 49 has a convex spherical surface 52 facing the outer wall 51, and the outer wall 51 has a concave spherical surface 53 facing the inner wall 49.
Have. At each free end portion of the inner wall portion 49 and the outer wall portion 51, the permanent magnet pieces 28 are arranged on a radius line L that forms an angle θ in a static state with respect to a Z axis that passes through the intersection point P and is perpendicular to the XY plane.
a and 28b are fixed to each other. One permanent magnet piece 28a fixed to the inner wall portion 50 and the other permanent magnet piece 28b.
Is magnetized to the N pole, and the other permanent magnet piece 2
The end of 8b facing the one permanent magnet piece 28a is magnetized to the S pole. Since the yoke 29 to which these permanent magnetized pieces 28a and 28b are fixed is made of a ferromagnetic material as described above, a closed loop shape is formed on the yoke 29 by the permanent magnet pieces 28a and 28b as shown by an imaginary line 55. A magnetic field is created.

Between the permanent magnet pieces 28a and 28b, an electromagnetic coil 27 wound in a spherical array is interposed. The electromagnetic coil 27 has a thickness of about 1 mm, and a gap of about 1 mm is formed between the surfaces on both sides and the permanent magnet pieces 28a, 28b. Each permanent magnet piece 28a, 2
8b is curved in an arc shape in the longitudinal direction perpendicular to the paper surface of FIG. 2, and the cross-sectional shape perpendicular to the longitudinal direction is rectangular. With this configuration, each permanent magnet piece 28a,
Compared with the case of forming 28b into a spherical shape, 28b can be processed with less labor, and the productivity can be improved.

FIG. 3 is a partially cutaway perspective view showing a part of the torque generating means 32 in an enlarged manner. The electromagnetic coil 27 has a first winding 56 that generates thrust on the yoke 29 around the X-axis, a plane parallel to the first winding 56, and a winding direction perpendicular to the first winding 56. , And a second winding 57 that generates thrust on the yoke 29 around the Y axis. First
The winding 56 is arranged to face one permanent magnet piece 28a fixed to the inner wall 49 of the yoke 29, and the second winding 57 is the other permanent magnet piece fixed to the outer wall 51 of the yoke 29. Although it is arranged to face 28b, this relationship may be reversed. These first and second windings 56,
As described above, the reference numeral 57 is flat, is formed in a spherical shape, and is fixed in a state of being stacked on each other. The second winding 57 has a cover body 5 made of a magnetically permeable material such as synthetic resin.
8, the cover body 58 is fixed to the base 22 of the base 24 at both longitudinal ends by a pair of brackets 59 shown in FIG.

When the first winding 56 is energized and a current i _A flows, a thrust force f _A is generated by Fleming's left-hand rule,
_A rotation torque of f _A × R1 can be generated around the X axis. When the second winding 57 is energized and the current i _B flows, the magnetic attraction force f _B is applied according to Fleming's left-hand rule.
To generate f _B about the Y axis, and f about the Y axis.
A rotation torque of _B × R2 can be generated. Further, when the directions of the currents i _A and i _B are reversed, magnetic attraction forces −f _A and −f _B are generated in the opposite directions, and accordingly, rotational torque can be generated in the opposite directions.

FIG. 4 is a block diagram showing the electrical construction of the control means 33. The control means 33 is basically the first
It has a winding energization control circuit 61 and a second winding energization control circuit 62. The first winding energization control circuit 61 uses the comparison operator 6
3a, the angular velocity command value given as the reference input and the X-axis angular velocity feedback amount are compared and calculated, and the calculation result is input to the compensation circuit 64a as a control amount, which is proportional to the preset target value. Integration / differentiation (abbreviation P)
ID) operation is performed, and a torque command signal which is an adjustment signal of the calculation result is input to the first winding drive circuit 65a. In the first winding drive circuit 65a, for example, pulse width modulation (abbreviated as PWM) is performed, and the output thereof outputs the first winding 56.
It is possible to control the energization amount of.

The other second winding energization control circuit 62 is
The first winding energization control circuit 61 has the same configuration as that of the first winding energization control circuit 61 described above.

With the above configuration, the X axis and the Y axis
Thrust forces f _A and f _{B at} positions having R1 and R2 respectively from the shaft
It is possible to rapidly settle the mounting base 26 due to disturbance, and hence the posture change of the mounted object mounted on the mounting base 26, with a large rotational torque. Also apparently 1
Since torque can be generated about two axes by the torque generating means 32 provided at the location, even if the overall configuration is downsized by this, the torque generator does not limit the installation space of the mounted object and is relatively small. It is possible to easily mount the mounted object on the mounting base 26.

In the above-described embodiment, the torque generating means 32 is provided at a position inclined by the angle θ with respect to the Z axis. However, as another embodiment of the present invention, the one radial line L is on the Z axis. The torque generating means 32 may be connected to the lower portion of the mounting base 26 so as to be arranged in the position. As a result, the torque generating means 32 can be arranged in the space below the gimbal frame 25 and the mounting base 26, and the mountable space of the mounted object can be further increased.

In the above embodiment, the X-axis angular velocity sensor 30 and the Y-axis angular velocity sensor 31 are used as means for detecting the rotational angular velocity of the gimbal frame 25 and the mounting base 26 with respect to the X-axis and the Y-axis. You may make it use the thing etc. which detect the biaxial angular velocity sensor by one sensor.

[0023]

As described above, according to the present invention, the torque generating means constituted by the electromagnetic coil and the yoke is provided on the mounting base to generate the torque around the first and second axes, and to the base. The mount can be stabilized against the disturbance input of. Moreover, since the torque generating means is arranged at a position away from the intersection of the first and second axes, the installation space of the object to be mounted on the mounting base is not restricted, and therefore the degree of freedom in design is not restricted, and a wide range is achieved. It becomes possible to mount a model or a type of payload.

[Brief description of drawings]

FIG. 1 is a perspective view showing a space stabilizer 21 using a gimbal mechanism according to an embodiment of the present invention.

FIG. 2 is a partial cross-sectional view showing a specific configuration of the space stabilizer 21.

FIG. 3 is a partial perspective view showing the torque generating means 32 partially cut away.

FIG. 4 is a block diagram showing an electrical configuration of control means 33.

FIG. 5 is a perspective view showing a space stabilizer 1 using a typical prior art gimbal mechanism.

[Explanation of symbols]

 21 Space Stabilizer 24 Base 25 Gimbal Frame 26 Mounting Base 27 Electromagnetic Coil 28a, 28b Permanent Magnet Piece 29 Yoke 30 X-axis Angular Speed Sensor 31 Y-axis Angular Speed Sensor 32 Torque Generating Device 33 Controlling Device 56 First Winding 57 Second Roll line

Claims (2)

[Claims] 1. A base, a gimbal frame rotatably supported on the base around a first axis, and a gimbal frame rotatable about a second axis orthogonal to the first axis. A mounting base that is supported and on which a mounting object is mounted, a flat electromagnetic coil that is provided on the base in a spherical shape with the intersection of the first and second axes as a spherical center, and a ferromagnetic material that is provided on the mounting base. And a substantially C-shaped yoke having opposite ends on both sides in the thickness direction of the electromagnetic coil and having magnetic poles, the current flowing to the electromagnetic coil is controlled to serve as a torque generating means. mechanism. 2. The electromagnetic coil comprises a first winding that generates a torque around a first axis, a plane parallel to the first winding, and a winding direction perpendicular to the first winding. The gimbal mechanism according to claim 1, further comprising a second winding that generates a torque around the second axis.