JP5223788B2 - Gimbal equipment - Google Patents

Description

  The present invention relates to a gimbal device, and more particularly to a gimbal device in which a camera is mounted.

  When a camera is mounted on an aircraft, a method of installing the camera in a gimbal device (space stabilization device) is generally used in order to prevent camera image blurring caused by vibration of the airframe. The most important requirement for gimbal equipment is high spatial stability, but in recent years there has been a demand for mounting multiple cameras, side distance devices, etc. on an aircraft, and there has been a strong demand for smaller size, lighter weight and lower power consumption. It is like that.

  The problem in securing the space stability of the gimbal device is the vibration transmitted from the airframe and the deflection of the gimbal device itself due to this. In order to solve these problems, it is conceivable to use a method of using a vibration-proof mount or a method of increasing the rigidity of the gimbal, but both increase the weight of the device and cannot satisfy the above-mentioned demands. .

  Therefore, conventionally, a technique has been used in which an angular velocity sensor is attached to the camera installation portion of the gimbal device and vibration correction control is performed based on a signal detected by the angular velocity sensor. Is disclosed.

Japanese Patent Laid-Open No. 11-252461

  However, in the control device using such an angular velocity sensor, due to the influence of the deflection of the gimbal device, the drive power for control is saturated, the control deviation increases, and image blurring may occur in the camera image.

  The gimbal device is easily bent in the left-right direction for structural reasons, and the angular velocity sensor attached to the camera unit is greatly affected by the deflection as the visual axis of the camera approaches the vertical direction. When the deflection becomes large and the detected value of the angular velocity sensor exceeds a certain magnitude, the influence of the deflection cannot be attenuated in the control device, and the control deviation is deteriorated to cause image blurring.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a gimbal apparatus that can ensure high spatial stability by eliminating the influence of flexural vibration with a simple configuration.

From one perspective,
A gimbal portion that is mounted on the moving body and moves the viewing axis of the camera installed by being driven by the driving portion with respect to the moving body;
A first angular velocity around a vertical axis of the visual axis of the camera, a second angular velocity around a second axis in a direction different from the vertical axis of the visual axis of the camera, and a third angular velocity around the visual axis depression axis direction. An angular velocity detector for detecting angular velocity;
Control means for performing drive control of the drive unit based on the acceleration detection unit,
The control means includes
A first visual axis computing unit for obtaining a first corrected angular velocity for correcting deflection using the first angular velocity;
A second visual axis computing unit for obtaining a second corrected angular velocity for correcting deflection using the second angular velocity;
A switching processor that is connected to the first and second visual axis computing units and determines whether to output the first correction angular velocity or the second correction angular velocity based on an angle of the visual axis in the depression axis direction; ,
A gimbal apparatus is provided that includes a compensator that controls driving of the driving unit based on the first or second corrected angular velocity determined by the switching processor.

  The disclosed gimbal device can simplify the configuration and can eliminate the influence of flexural vibration to ensure high spatial stability.

FIG. 1 is a perspective view showing an outline of a gimbal device. FIG. 2A is an explanatory diagram for explaining the influence of deflection when the camera faces the horizontal direction, and FIG. 2B shows a camera image when the camera faces the horizontal direction. It is. FIG. 3A is an explanatory diagram for explaining the influence of deflection when the camera is oriented in the vertical direction, and FIG. 3B is a diagram illustrating a camera image when the camera is oriented in the vertical direction. It is. FIG. 4 is a diagram for explaining the mechanism of occurrence and detection of deflection. FIG. 5 is a diagram illustrating an example of platform vibration conditions. FIG. 6 is a diagram illustrating an example of gimbal mechanism transmission characteristics. FIG. 7 shows a gimbal device which is an example of the present embodiment. FIG. 7A is a front view and FIG. 7B is a side view. It is a functional block diagram which shows the structure of the angular velocity control apparatus which concerns on the example of this embodiment. It is a block diagram which shows the switching process of the angular velocity control apparatus which concerns on this embodiment. It is a functional block diagram which shows the structure of the angular velocity control apparatus which is a reference example of the angular velocity control apparatus which concerns on this embodiment. FIG. 11 is a diagram illustrating the relationship between the angle of the visual axis in the depression axis direction and the corrected angular velocity reflected by the compensator. FIG. 12 is a diagram for explaining the reflection ratio of the angle of the visual axis in the depression axis direction and the first and second corrected angular velocities (No. 1). FIG. 13 is a diagram for explaining the reflection ratio of the angle of the visual axis in the depression axis direction and the first and second corrected angular velocities (part 2).

  Next, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 shows a gimbal device 1 according to an embodiment of the present invention. In this embodiment, a gimbal device mounted on an aircraft will be described as an example. However, the application of the present invention is not limited to an aircraft, and can be applied to other transfer devices such as ships.

  The gimbal device 1 includes an airframe attachment surface 2 attached to an aircraft platform, an AZ turning portion 3 that is rotatable about an AZ (azimuth) axis with respect to the airframe attachment surface 2, and an EL relative to the AZ turning portion 3. (Elevation) It has a camera mounting portion 4 that is rotatable about an axis and in which a camera is mounted.

  Driving torque motors are arranged on the AZ axis and the EL axis. When each torque motor is driven, the AZ turning unit 3 is oriented in the horizontal direction of 0 to 360 degrees, and the camera mounting unit 4 is oriented in the horizontal to vertical directions. To do. The camera is housed in the camera mounting unit 4 that rotates around the EL axis as described above. In addition, an angular velocity sensor serving as the angular velocity detection unit 210 is also mounted in the camera mounting unit 4 and has a mechanism for detecting the magnitude of camera axis blur as an angular velocity.

  By the way, the gimbal device 1 is easily bent in the left-right direction of the visual axis, which is the weakest direction of the structure. FIG. 2A is an explanatory diagram for explaining the influence of deflection when the camera is oriented in the horizontal direction. As shown in the figure, when the camera visual axis is oriented in the horizontal direction, the camera visual axis moves to the left and right small on an arc centered on the central position of the airframe mounting surface 2.

  FIG. 2B is a sample diagram of a camera image when the camera is oriented in the horizontal direction. As shown in the figure, when the camera is oriented in the horizontal direction, the camera image appears to be slightly rotated in the roll direction under the influence of deflection.

  When the angular velocity sensor 210 is mounted on the visual axis, the angular velocity sensor 210 detects the rotational angular velocity and is not affected at all by deflection. When viewed on the imaging screen, the above-described deflection appears as rotational vibration of the image. However, since the displacement angle component is small, the rotational vibration of the image is at a level that cannot be recognized, and there is no problem.

  On the other hand, as the elevation angle θEL (EL angle) of the visual axis increases, it is detected as a roll direction rotation component. That is, the influence of the deflection of the gimbal device 1 increases as the camera viewing axis approaches the vertical direction. FIG. 3A is an explanatory diagram for explaining the influence of deflection when the camera is oriented in the vertical direction. As shown in the figure, when the camera visual axis is oriented in the vertical direction, the camera visual axis reciprocates greatly to the left and right while facing the outside of the arc.

  FIG. 3B is a sample diagram of a camera image when the camera is oriented in the vertical direction. As shown in the figure, when the camera is oriented in the vertical direction, the camera image appears to vibrate greatly in the left-right direction under the influence of deflection. When the angular velocity sensor 210 is mounted on the visual axis, the angular velocity sensor 210 detects this large horizontal vibration as a flexural vibration component.

  When the angular velocity sensor 210 is mounted on the camera visual axis, the angular velocity signal detected by the angular velocity sensor 210 includes an AZ axis rotation component in addition to the roll direction rotation component and the flexural vibration component. This is due to a lack of strength at the airframe mounting portion, an insufficient output of the torque motor, or the like.

  Here, the mechanism of occurrence and detection of deflection will be described. FIG. 4 is an explanatory diagram for explaining the mechanism of occurrence and detection of deflection. The intensity of vibration transmitted to the gimbal device is expressed as acceleration (G), and this acceleration (G) is obtained by the vibration condition 10 of the platform (aircraft mounting surface) and the transfer function 20 of the gimbal mechanism.

  The platform vibration condition 10 represents the strength of vibration for each frequency of the platform (aircraft mounting surface of the aircraft). FIG. 5 is a sample diagram showing an example of the platform vibration condition 10. The figure shows that there is a random wave of a certain intensity at a frequency in the range of F1 to F2, and that there is a specifically strong sine wave at the frequency of F3. Such a sine wave is caused by, for example, engine characteristics.

  The gimbal mechanism transfer function 20 represents the ease of transmission of vibration for each frequency of the gimbal device. FIG. 6 is a sample diagram showing an example of the gimbal mechanism transfer function 20. The figure shows that vibration is amplified by resonance near the frequency of F0.

  The acceleration (G) of the vibration transmitted to the gimbal device is multiplied by the deflection angle T [rad / G] determined by the structural rigidity by the multiplier 35, whereby the deflection (displacement angle) [rad]. Occurs. Next, the deflection (displacement angle) is multiplied by sin (θEL) 40 to convert it into a deflection angle [rad] around the visual axis. The deflection angle [rad] around the visual axis is differentiated by the differentiator 50, and the angular velocity sensor 210 detects the angular velocity component [rad / s] of the differentiated deflection.

  Next, the angular velocity control of the gimbal device that is a premise of the present embodiment will be described. FIG. 10 is a block diagram for explaining the angular velocity control for driving the gimbal device. As shown in the figure, the gimbal device has a gimbal part 201 and a controller 101. The gimbal unit 201 includes an AZ turning unit 3 that rotates about the AZ axis, and a camera mounting unit 4 that rotates about the EL axis (see FIG. 1).

  The AZ turning unit 3 includes an amplifier 230 and a torque motor 240. The amplifier 230 is an amplifying device that amplifies electric power for driving the torque motor based on a control signal from the controller 101 in order to ensure space stability. The torque motor 240 drives the drive part of the gimbal part 201 and realizes space stability.

  The camera mounting unit 4 includes a camera and an angular velocity detection unit 210. The angular velocity detection unit 210 is an angular velocity sensor that detects an angular velocity, and is attached so as to always face the visual axis direction of the camera.

  The controller 101 is a control device that performs feedback control based on the signal detected by the angular velocity detection unit 210 so that there is no image blur of the camera installed in the gimbal unit 201. The controller 101 includes a noise removal filter 141, an AZ axis calculator 151, and a compensator 181.

  The noise removal filter 141 is an arithmetic unit that removes a noise component from the signal detected by the angular velocity detection unit 210. The AZ axis calculator 151 is a calculator that converts the angular velocity component around the visual axis detected by the angular velocity detector 210 into an angular velocity component around the AZ axis. The compensation unit 181 is an arithmetic unit that calculates a control amount necessary for realizing the angular velocity command 0 [rad / s] and transmits the control amount to the amplifier 230 of the gimbal unit 201.

  The reason why the AZ axis calculator 151 converts the angular velocity is that the vibration correction control in the gimbal unit 201 is performed in the direction around the AZ axis. This conversion is performed when the elevation angle of the visual axis of the camera is θEL. This is done by multiplying the angular velocity signal by / cos (θEL). For this reason, as the visual axis of the camera approaches the vertical direction, the signal is greatly amplified. When the elevation angle θEL is 85 degrees, the signal is amplified 11 times.

  As already described with reference to FIGS. 2 and 3, the flexural vibration component in the angular velocity signal detected by the angular velocity detector 210 increases as the visual axis of the camera approaches the vertical direction. Then, this is further amplified by the conversion of the AZ axis calculator 151. For this reason, in the angular velocity control which is the premise of the present embodiment shown in FIG. 10, when the camera visual axis approaches the vertical direction, the deviation from the command angular velocity increases, and the drive command to the amplifier 230 is saturated, resulting in a space. There was a situation that could not be stabilized.

  In the actual operation of the gimbal device, noise such as vibration synergizes with the signal from the angular velocity detection unit 210. Therefore, in the conventional controller 101, a limit (for example, −75 ° to + 75 °) is provided for the elevation angle θEL, and when the signal from the angular velocity detection unit 210 exceeds this limit, the controller 101 is stopped. Was done.

  As another angular velocity control, a first angular velocity detection unit is mounted on the camera mounting unit 4, and a second angular velocity detection unit is mounted on the AZ turning unit 3. Based on the signals of the two angular velocity detection units. There is a method for controlling the angular velocity of the gimbal device. In this method, the AZ axis rotation included in the signal detected by the first angular velocity detector is obtained by subtracting the signal detected by the second angular velocity detector from the signal detected by the first angular velocity detector. Components are removed in advance to improve the accuracy of angular velocity control. Further, when the camera elevation angle θEL is larger than a predetermined angle, the two angular velocity detectors are switched so that an angular velocity signal consisting only of the AZ axis rotation component is output.

  However, since this method requires two angular velocity detection units, there is a problem that the mounting space for the angular velocity detection unit is necessary for each of the AZ turning unit and the camera mounting unit, and the cost is increased.

  Next, the angular velocity control applied to the gimbal device 1 according to the present embodiment will be described.

  FIG. 7 shows an arrangement position of the angular velocity detection unit 210 (angular velocity sensor) used in the gimbal device 1 according to the present embodiment. The angular velocity detection unit 210 is mounted in the camera mounting unit 4, and its arrangement position is a position near the camera 6. The angular velocity detection unit 210 detects a spatial angular velocity around the visual axis of the camera. Specifically, the angular velocity detection unit 210 used in this embodiment includes an angular velocity u [1] around the visual axis vertical direction axis, an angular velocity u [2] around the visual axis back direction axis of the camera, and the visual axis elevation axis. It is possible to detect acceleration around all three axes with the angular velocity u [EL] in the direction.

  FIG. 8 is a block diagram for explaining the angular velocity control method of the gimbal device 1 according to this embodiment, and FIG. 9 is a block diagram for explaining the calculation contents of the switching processor 160 shown in FIG. 9 and 8, the components corresponding to those shown in FIG. 10 used for explaining the angular velocity control method which is the premise of the present embodiment are described with the same reference numerals.

  As shown in FIG. 8, the gimbal device has a controller 100 and a gimbal part 200. The gimbal unit 200 includes an AZ turning unit 3 that rotates about the AZ axis, and a camera mounting unit 4 that rotates about the EL axis (see FIG. 7).

  The AZ turning unit 3 includes an amplifier 230 and a torque motor 240. The amplifier 230 is an amplifying device that amplifies electric power for driving the torque motor based on a control signal from the controller 100 in order to ensure space stability. The torque motor 240 drives the drive part of the gimbal part 200, and implement | achieves space stability.

  The camera mounting unit 4 includes a camera and angular velocity detection unit 210. The angular velocity detection unit 210 is an angular velocity sensor that detects an angular velocity, and is attached so as to always face the visual axis direction of the camera. As the angular velocity detection unit 210, one that can detect accelerations around the three axes of the angular accelerations u [1], u [2], and u [EL] is selected.

  The controller 100 is a control device that performs feedback control based on the signal detected by the angular velocity detection unit 210 so that there is no image blurring of the camera installed in the gimbal unit 200. The controller 100 includes a first visual axis calculator 110A, a second visual axis calculator 110B, a switching processor 160, an EL visual axis angle 130, a first input range limiter 120A, a second input range limiter 120B, A compensator 180 is provided.

  The angular velocity u [1] around the visual axis vertical direction detected by the angular velocity detection unit 210 is input to the first visual axis calculator 110A. Further, the angular velocity u [2] around the rear axis of the visual axis of the camera detected by the angular velocity detection unit 210 is input to the second visual axis calculator 110B.

  The first visual axis calculator 110A is a processor that converts the input angular velocity signal u [1] around the visual axis vertical direction axis into angular velocity u [3] around the AZ axis. Specifically, the first visual axis calculator 110A calculates u [3] = u [1] ÷ cos (θEL).

  The first visual axis calculator 110A performs the above calculation process only when the calculation permission of the first input range limiter 120A is obtained. The first input range limiter 120A is a condition determination flag generator that prevents the cos (θEL) division result from being ∞ (NAN).

  Then, the first input range limiter 120A refers to the EL visual axis angle 130 (calculates the elevation angle θEL of the visual axis), and when the division result is ∞ (NAN), “u [8] = 0” Otherwise, “u [8] = 1” is output. Then, the first visual axis calculator 110A refers to the output u [8] determined by the first input range limiter 120A, and performs the visual axis conversion calculation only when u [8] is “1”.

  On the other hand, the second visual axis calculator 110B is a processor that converts the input angular velocity signal u [2] around the vertical axis of the visual axis into angular velocity u [4] around the AZ axis. Specifically, the second visual axis calculator 110B calculates u [4] = u [2] ÷ sin (θEL).

  The second visual axis calculator 110B performs the above calculation process only when the calculation permission of the second input range limiter 120B is obtained. The second input range limiter 120B is a condition determination flag generator that prevents the sin (θEL) division result from being ∞ (NAN).

  Then, the second input range limiter 120B refers to the EL visual axis angle 130, and when the division result is ∞ (NAN), “u [9] = 0”, otherwise “u [9] = 1. Is output. Then, the second visual axis calculator 110B refers to the output u [9] determined by the second input range limiter 120B, and calculates the visual axis conversion only when u [9] is “1”.

  The angular velocities u [3] and u [4] around the AZ axis calculated by the first and second visual axis calculators 110A and 110B as described above are sent to the switching processor 160. In addition, the elevation angle θEL of the visual axis obtained from the EL visual axis angle 130 is also sent to the switching processor 160.

  Based on the angle u [5] (u [5] = θEL) in the elevation direction of the visual axis, the switching processor 160 is connected to the angular velocity u [3] around the AZ axis sent from the first visual axis calculator 110A. The mixing ratio with the angular velocity u [4] around the AZ axis sent from the second visual axis calculator 110B is changed and reflected in the processing of the compensator 180. The compensator 180 is an arithmetic unit that calculates a control amount necessary for realizing the angular velocity command 0 [rad / s] and transmits the control amount to the amplifier 230 of the gimbal unit 200.

  Here, the process performed by the switching processor 160 will be described in detail. FIG. 9 is a block diagram showing the switching process of the switching processor 160. The angular velocity u [3] in the visual axis elevation axis direction from the first visual axis calculator 110A is multiplied by the reflection rate u [6] of the first visual axis calculator 110A in the switching processor 160. Further, the angular velocity u [4] around the AZ axis from the second visual axis calculator 110B is multiplied by the reflection rate u [7] of the second visual axis calculator 110B in the switching processor 160.

  Then, the calculated value obtained by multiplying the angular velocity u [3] in the visual axis elevation axis direction by the reflection rate u [6] of the first visual axis calculator 110A and the angular velocity u [4] around the AZ axis are set to the second visual axis. The calculated value multiplied by the reflection ratio u [7] of the calculator 110B is added by the adder 190. The calculation result u [8] (hereinafter referred to as the reflected angular velocity u [8]) thus obtained is output as a feedback signal from the switching processor 160 to the compensator 180.

  Here, the reflection ratio u [6] of the first visual axis calculator 110A and the reflection ratio u [7] of the second visual axis calculator 110B are based on the reflection ratio map 140 stored in the switching processor 160 in advance. It is determined. The reflection ratio map 140 is based on the angle u [5] in the elevation direction of the visual axis input from the EL visual axis angle 130, and the reflection ratio u [6] of the first visual axis calculator 110A and the second visual axis calculator. It is a binary map which determines the reflection ratio u [7] of 110B.

  As shown in the figure, the reflection ratio map 140 is a map in which the horizontal axis represents the angle u [5] (θEL) in the elevation direction of the visual axis and the vertical axis represents the reflection ratio [%]. As shown in the figure, the reflection rate u [6] of the first visual axis calculator 110A is such that the angle u [5] in the elevation direction of the visual axis is −180 ° to −140 °, −40 ° to + 40 °, +140. In the case of ° to +180, it is 100%. On the other hand, when the angle u [5] in the elevation direction of the visual axis is −130 ° to −50 °, + 50 ° to + 130 °, the reflection rate u [6] of the first visual axis calculator 110A is 0. %.

  On the other hand, the reflection rate u [7] of the second visual axis calculator 110B is 100% when the angle u [5] of the visual axis in the elevation direction is −130 ° to −50 °, + 50 ° to + 130 °. It has become. On the other hand, when the angle u [5] in the elevation direction of the visual axis is −180 ° to −140 °, −40 ° to + 40 °, + 140 ° to + 180 °, the second visual axis calculator 110B The reflection rate u [7] is 0%.

  Further, the angle u [5] in the elevation direction of the visual axis is −140 ° to −130 ° (referred to as the first mixing region M1), −50 ° to −40 ° (referred to as the second mixing region M2), + 40 ° to +50. The range of ° (referred to as the third mixing region M3) and + 130 ° to + 140 ° (referred to as the fourth mixing region M4) is the reflection ratio u [6] of the first visual axis calculator 110A and the second visual axis calculator 110B. The reflection rate u [7] is set to change gradually.

  Specifically, in the first mixing region M1 and the third mixing region M3, the reflection rate u [6] of the first visual axis calculator 110A gradually decreases from 100% to 0%, and conversely the second visual axis calculation. The reflection rate u [7] of the container 110B gradually increases from 0% to 100%. In the second mixing region M2 and the fourth mixing region M4, the reflection ratio u [6] of the first visual axis calculator 110A gradually increases from 0% to 100%, and conversely, the second visual axis calculator 110B. The reflection rate u [7] gradually decreases from 100% to 0%. Accordingly, in each mixing region M1 to M4, the reflection ratio u [6] of the first visual axis calculator 110A and the reflection ratio u [7] of the second visual axis calculator 110B are smoothly switched.

  FIG. 11 is a diagram showing the relationship between the angle u [5] of the visual axis in the elevation direction and the magnification u [8] of the reflected angular velocity. As shown in the figure, when the angle u [5] of the visual axis is −180 ° to −140 °, −40 ° to + 40 °, + 140 ° to + 180 °, the reflected angular velocity u [8] An angular velocity u [3] in the visual axis elevation axis direction is output. In addition, when the angle u [5] in the elevation direction of the visual axis is in the range of −130 ° to −50 ° and + 50 ° to + 130 °, the angular velocity u [4] around the AZ axis is output as the reflected angular velocity u [8]. ing. Further, in each of the first mixing region M1 to the fourth mixing region M4, the angular velocities u [3], u at a rate corresponding to each reflection rate u [6], u [7] shown in the reflection rate map 140. The value obtained by mixing [4] is output as the reflected angular velocity u [8].

  Next, using FIG. 12 and FIG. 13, the angle u [5] in the elevation direction of the visual axis and the acceleration around the three axes detected by the angular velocity detection unit 210 (the angular velocity u [1 around the visual axis vertical direction axis). ], Angular velocity u [2] around the back axis of the visual axis of the camera, and angular velocity u [EL] in the visual axis elevation axis direction will be described.

  FIG. 12A shows a state where the angle u [5] in the elevation direction of the visual axis is + 90 °. At this time, the visual axis is directed directly above, the angular velocity u [1] around the vertical axis of the visual axis is directed horizontally, and the angular velocity u [2] around the rear axis of the visual axis of the camera is It faces vertically downward.

  Here, assuming that the angular velocity u [1] around the visual axis vertical axis is used for the calculation of the reflected angular velocity u [8], the first visual axis calculator 110A uses the angular velocity u [1 around the visual axis vertical direction. ] Is divided by cos (θEL), the angular velocity u [3] in the visual axis elevation axis direction approaches infinity, and the deviation between the command value and the feedback value increases, making it impossible to control the torque motor 240. There is a fear. For this reason, in the present embodiment, when the angle u [5] of the visual axis in the elevation direction is + 90 °, only the angular velocity u [2] around the visual axis back direction axis of the camera is used for the calculation of the reflected angular velocity u [8]. Used.

  FIG. 12B shows a state where the angle u [5] in the elevation direction of the visual axis is + 45 °. At this time, the visual axis is inclined 45 ° obliquely upward with respect to the horizontal direction, and the angular velocity u [1] around the vertical axis of the visual axis and the angular velocity u [2] around the back axis of the visual axis of the camera are vertically downward It is in a state tilted ± 45 ° around the center.

  Here, referring to the reflection ratio map 140 shown in FIG. 9, the reflection ratio u [6] of the first visual axis calculator 110A and the reflection ratio of the second visual axis calculator 110B when u [5] is + 45 °. Both u [7] are 50%. Therefore, when the angle u [5] in the elevation direction of the visual axis is + 45 °, the angular velocity u [1] around the vertical axis of the visual axis and the back axis of the camera's visual axis are used to obtain the reflected angular velocity u [8]. The reflected angular velocity u [8] is obtained by using both of the angular velocities u [2] and adding (mixing) each at a reflection ratio of 50%.

  FIG. 12C shows a state where the angle u [5] in the elevation direction of the visual axis is ± 0 °. At this time, the visual axis is oriented horizontally, the angular velocity u [1] around the visual axis vertical axis is oriented vertically downward, and the angular velocity u [2] around the rear axis of the camera's visual axis is horizontal. Facing the direction.

  For the same reason as above, when the angular velocity u [2] around the vertical axis of the visual axis is used to calculate the reflected angular velocity u [8], the angular velocity u [4] around the AZ axis approaches infinity, The deviation between the value and the feedback value becomes large, and the torque motor 240 may not be controlled. Therefore, in this embodiment, when the angle u [5] of the visual axis in the elevation direction is ± 0 °, only the angular velocity u [1] around the visual axis vertical axis is used for the calculation of the reflected angular velocity u [8]. ing.

  FIG. 13A shows a state where the angle u [5] of the visual axis in the elevation direction is −45 °. At this time, the visual axis is inclined 45 ° obliquely downward with respect to the horizontal direction. The angular velocity u [1] around the vertical axis of the visual axis and the angular velocity u [2] around the rear axis of the visual axis of the camera are in the horizontal direction. It is in a state tilted ± 45 ° around the center.

  Here, referring to the reflection ratio map 140 shown in FIG. 9, when u [5] is −45 °, the reflection ratio u [6] of the first visual axis calculator 110A and the reflection of the second visual axis calculator 110B. The proportions u [7] are both 50%. Therefore, when the angle u [5] in the elevation direction of the visual axis is −45 °, the angular velocity u [1] around the vertical axis of the visual axis and the back axis of the visual axis of the camera are used to obtain the reflected angular velocity u [8]. The reflection angular velocity u [8] is obtained by using both of the angular velocities u [2] around and adding (mixing) each at a reflection ratio of 50%.

  FIG. 13B shows a state where the angle u [5] of the visual axis in the elevation direction is −90 °. At this time, the visual axis is directed vertically downward, the angular velocity u [1] around the visual axis vertical direction is oriented in the horizontal direction, and the angular velocity u [2] around the visual axis rear direction axis of the camera is true. It faces upward.

  For the same reason as described above, when the angular velocity u [1] around the vertical axis of the visual axis is used to calculate the reflected angular velocity u [8], the angular velocity u [3] in the visual axis elevation axis direction approaches infinity. The deviation between the command value and the feedback value becomes large, and the torque motor 240 may not be controlled. For this reason, in the present embodiment, when the angle u [5] of the visual axis in the elevation direction is −90 °, only the angular velocity u [2] around the visual axis back direction axis of the camera is reflected to calculate the angular velocity u [8]. Used for.

  Further, FIG. 13C shows a state where the angle u [5] of the visual axis in the elevation direction is −135 °. At this time, the visual axis is inclined 45 ° obliquely downward with respect to the horizontal direction, and the angular velocity u [1] around the vertical axis of the visual axis and the angular velocity u [2] around the rear axis of the camera's visual axis are directly above. It is in a state tilted ± 45 ° around the direction.

  Here, referring to the reflection ratio map 140 shown in FIG. 9, the reflection ratio u [6] of the first visual axis calculator 110A and the reflection of the second visual axis calculator 110B when u [5] = − 135 °. The proportions u [7] are both 50%. Therefore, when the angle u [5] in the elevation direction of the visual axis is −135 °, the angular velocity u [1] around the vertical axis of the visual axis and the back axis of the visual axis of the camera are used to obtain the reflected angular velocity u [8]. The reflection angular velocity u [8] is obtained by using both of the angular velocities u [2] around and adding (mixing) each at a reflection ratio of 50%.

  As described above, the switching processor 160 uses the angular velocity u [3] in the visual axis elevation axis direction and the angular velocity u [4] around the AZ axis based on the reflection ratio map 140 to the angle u [5] in the visual axis elevation direction. By switching with reference to, deflection amplification can be suppressed to amplification of about 45 °. For this reason, according to the acceleration control method according to the present embodiment, the influence of the deflection disturbance can be suppressed by about 1/6 (θEL-80 degrees) compared to the conventional acceleration control method, and the spatial stability in the direction of the entire visual axis. Can be achieved.

  Further, since the angular velocity control method used in this embodiment is not easily affected by the flexural vibration as described above, the stability of the control loop can be ensured compared to the conventional angular velocity control method, and the power consumption of the torque motor 240 can be reduced. Can be achieved. In addition, since only one angular velocity detection unit 210 is used, the size of the gimbal device 1 can be reduced.

  The preferred embodiments of the present invention have been described in detail above. However, the present invention is not limited to the specific embodiments described above, and various modifications are possible within the scope of the gist of the present invention described in the claims. It can be modified and changed.

  For example, in the present embodiment, the range of each of the mixing regions M1 to M4 is set to 10 °, but the range of the mixing regions M1 to M4 is not limited to this, and can be set as appropriate.

Regarding the above embodiment, the following additional notes are disclosed.
(Appendix 1)
A gimbal portion that is mounted on the moving body and moves the viewing axis of the camera installed by being driven by the driving portion with respect to the moving body;
A first angular velocity around a vertical axis of the visual axis of the camera, a second angular velocity around a second axis in a direction different from the vertical axis of the visual axis of the camera, and a third angular velocity around the visual axis depression axis direction. An angular velocity detector for detecting angular velocity;
Control means for performing drive control of the drive unit based on the acceleration detection unit,
The control means includes
A first visual axis computing unit for obtaining a first corrected angular velocity for correcting deflection using the first angular velocity;
A second visual axis computing unit for obtaining a second corrected angular velocity for correcting deflection using the second angular velocity;
A switching processor that is connected to the first and second visual axis computing units and determines whether to output the first correction angular velocity or the second correction angular velocity based on an angle of the visual axis in the depression axis direction; ,
A gimbal apparatus comprising: a compensator that controls driving of the drive unit based on the first or second corrected angular velocity determined by the switching processor.
(Appendix 2)
The gimbal device according to appendix 1, wherein the second angular velocity is an angular velocity around a back-direction axis with respect to the visual axis.
(Appendix 3)
The supplementary note 1 or 2, wherein the switching processor gradually changes a ratio of the first correction angular velocity and the second correction angular velocity reflected in the output correction angular velocity based on an angle of the visual axis in the depression axis direction. Gimbal device.
(Appendix 4)
The first visual axis calculator is configured to perform the first correction angular velocity based on a depression angle of the visual axis,
When the depression angle value of the visual axis is a value that makes the first correction angular velocity calculated by the first visual axis calculator infinite, the depression angle value of the visual axis is calculated as the first visual axis calculation. 4. The gimbal device according to any one of appendices 1 to 3, further comprising a first input controller that prohibits input to the instrument.
(Appendix 5)
The second visual axis calculator is configured to perform the second corrected angular velocity based on a depression angle of the visual axis,
When the depression angle value of the visual axis is a value that makes the second correction angular velocity calculated by the second visual axis calculator infinite, the depression angle value of the visual axis is calculated as the second visual axis calculation. The gimbal device according to any one of appendices 1 to 4, further comprising a second input controller that prohibits input to the instrument.

DESCRIPTION OF SYMBOLS 1 Gimbal apparatus 2 Airframe attachment surface 3 AZ turning part 4 Camera mounting part 100 Controller 110A 1st visual axis calculator 110B 2nd visual axis calculator 120A 1st input range limiter 120B 2nd input range limiter 130 EL visual axis Angle 140 Reflection ratio map 160 Switching processor 180 Compensator 200 Gimbal part 210 Angular velocity detection part 240 Torque motor
u [1] Angular velocity around the visual axis
u [2] Angular velocity around the back axis of the camera's visual axis
u [3] Angular velocity in visual axis / elevation axis direction
u [4] Angular velocity around the AZ axis
u [5] Angle of elevation of the visual axis
u [6] Reflection ratio of the first visual axis calculator 110A
u [7] Reflection ratio of second visual axis calculator 110B
u [8] Reflected angular velocity

Claims (3)

A gimbal portion that is mounted on the moving body and moves the viewing axis of the camera installed by being driven by the driving portion with respect to the moving body;
A first angular velocity around a vertical axis of the visual axis of the camera, a second angular velocity around a second axis in a direction different from the vertical axis of the visual axis of the camera, and a third angular velocity around the visual axis depression axis direction. An angular velocity detector for detecting angular velocity;
Control means for performing drive control of the drive unit based on the acceleration detection unit,
The control means includes
A first visual axis computing unit for obtaining a first corrected angular velocity for correcting deflection using the first angular velocity;
A second visual axis computing unit for obtaining a second corrected angular velocity for correcting deflection using the second angular velocity;
A switching processor that is connected to the first and second visual axis computing units and determines whether to output the first correction angular velocity or the second correction angular velocity based on an angle of the visual axis in the depression axis direction; ,
A gimbal apparatus comprising: a compensator that controls driving of the drive unit based on the first or second corrected angular velocity determined by the switching processor.   The gimbal apparatus according to claim 1, wherein the second angular velocity is an angular velocity around a back axis with respect to the visual axis.   3. The switching processor gradually changes the ratio of the first correction angular velocity and the second correction angular velocity reflected in the output correction angular velocity based on the angle of the visual axis in the depression axis direction. The gimbal device described.

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