JPH1124718A - Device and method for controlling robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a controller and method for a space robot by which a manipulator can be smoothly operated even when information which is different in detection cycle is used. SOLUTION: The controller for the space robot which is mounted on an artificial satellite has a sensor group of an inertia sensor which detects the position and speed of the satellite, a visual sensor which detects the relative position and speed of a floating target to be acquired, a proximity sensor mounted on the manipulator, etc., a main body position and speed interpolating means 40 which interpolates information obtained from the inertia sensor with control cycles of the manipulator, and a target position and speed interpolating means 39 which performs interpolation with the control cycles of the manipulator on the basis of visual sensor information so as to allow the satellite to trace the target and also positions the gripper of the manipulator where the part to be gripped of the target can be gripped on the basis of proximity sensor information.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device and a control method for controlling a robot used for assembling work or maintenance work in a floating space such as underwater or space.

[0002]

2. Description of the Related Art Conventionally, a space robot 21 configured by mounting a manipulator on an artificial satellite includes an artificial satellite 22 and a manipulator 23 mounted on the artificial satellite 22, as shown in FIG.

The artificial satellite 22 includes an inertial sensor 24 for detecting the position and speed of the artificial satellite, a relative position between a target (not shown) to be captured and the artificial satellite 22,
A visual sensor 25 for recognizing the speed and an artificial satellite 22
Devices 26a and 26 for controlling the flight and attitude of the aircraft
b, 26c.

On the other hand, the manipulator 23 is provided with a gripper 27 at its tip. This gripper 27
Is mounted with a force sensor 28 for detecting a force applied to the gripper 27. Also, the gripper 27
A proximity sensor 29 for detecting the relative position and posture of the gripper 27 and a portion to be gripped by a target (not shown) is provided in the vicinity of.

In the control device of the space robot, the position and speed of the artificial satellite and the target are detected by the visual sensor 25 mounted on the artificial satellite, and the manipulator tip speed generator 34 operates the manipulator 23 based on this information. Then, the manipulator follows the flight target in the outer space by generating the tip speed of the manipulator in consideration of the change in the position and attitude of the artificial satellite 22 accompanying the above. Further, the manipulator trajectory generator 23 generates an approach trajectory of the target using information on the relative position and posture of the gripped portion of the target and the gripper obtained by the proximity sensor 29. The position of the tip of the manipulator is controlled by the sensation sensor 28 according to the external force.

Here, the joint angle from the position detector of each joint of the manipulator, the force sensor 28 at the tip of the manipulator,
Is detected at a period of the manipulator control device of the space robot of about several msec to about several tens msec.
On the other hand, translation, rotation speed, and the like from sensors mounted on the artificial satellite 22 are detected at a period of the space robot attitude control device of about ten to several tens msec.

On the other hand, visual information from a visual sensor mounted on an artificial satellite and target position / posture information from a proximity sensor at the tip of the manipulator are used to remove noise, perform frame processing, Because it takes time for image processing such as binarization, several tens of msec to several hundreds of ms
It is generally detected at the ec cycle.

For this reason, the manipulator trajectory generator 33
Target position input, the speed, the body velocity ^A V _C ^m to be input to the manipulator tip velocity generator 34, the body angular velocity omega _C ^m, the current position of the manipulator generated by the coordinate converter 37 ^A P _m ^m, rotating The rotation matrix ^C T _A generated by the matrix generator 38 is updated at the above-described detection cycle.

[0009]

As described above, the speed information of the satellite main body from the inertial sensor 24 and the visual sensor 2
When driving each joint of the manipulator 23 using the position and orientation information of the target from the proximity sensor 5 and the proximity sensor 29, if the above information is used as it is, the manipulator 23
Operates intermittently in a cycle in which the information of the inertial sensor 24, the visual sensor 25, and the proximity sensor 29 is detected.

For this reason, there has been a demand for a control method for smoothly interpolating information from the visual sensor 25 and the proximity sensor 29 in the control cycle of the manipulator control device of the space robot.

Accordingly, the present invention satisfies the above-mentioned demands and provides a robot control apparatus and method capable of operating a robot smoothly using information from an inertial sensor 24, a visual sensor 25, and a proximity sensor 29. It is intended to provide.

[0012]

A first feature of the present invention is as follows.
A robot having a robot body and a manipulator mounted on the robot body, a robot control device for controlling the robot so as to be able to capture a target floating in space, the position of the robot body,
An inertial sensor mounted on the robot body to detect the speed, a relative position between the robot body and the target, a visual sensor to detect the speed, and a relative position and speed between the gripper of the manipulator and the target Proximity sensor mounted on the manipulator, a body position / velocity interpolation means for interpolating information obtained from the inertial sensor in the control cycle of the manipulator, and a robot body based on the information obtained from the visual sensor. Proximity sensor to interpolate the visual sensor information at the control cycle of the manipulator to track the target, and to position the gripper at the position where the gripped portion of the target can be gripped based on the information obtained from the proximity sensor. Target position / velocity interpolation means for interpolating information at the control cycle of the manipulator. And it is that it is.

Therefore, the manipulator can be smoothly operated by interpolating information from the inertial sensor, the visual sensor, and the proximity sensor in the control cycle of the manipulator control device, and the target can be captured with a stable operation. .

A second feature of the present invention is that the visual sensor mounted on the robot body also has a function of a proximity sensor for recognizing the relative position and speed between the gripped portion of the target and the gripper at the tip of the manipulator. It is. Further, a third feature of the present invention is that the proximity sensor mounted on the manipulator also has the function of a visual sensor for recognizing the relative position and speed between the target and the robot body.

Therefore, the number of necessary devices can be reduced, and the cost of the robot as a whole can be reduced.

According to a fourth feature of the present invention, an inertial sensor mounted on the robot body for detecting the position and speed of the robot body, and a relative position and speed between the robot body and a target to be captured are detected. A robot equipped with a visual sensor mounted on the robot body, and a proximity sensor mounted on the manipulator for detecting a relative position / velocity between a gripper of the manipulator provided on the robot body and the target. A robot body that interpolates information obtained from a visual sensor in a control cycle of a manipulator and, based on the interpolated information, matches a tip of the manipulator to a gripped portion of a target. Trajectory, and then generate a drive command to drive the propulsion device of the robot body to track the target. The stage and the change of the position and posture of the robot body due to the operation of the manipulator are detected by the inertial sensor, and the detected information is interpolated in the control cycle of the manipulator. Driving the manipulator to position the tip of the manipulator to the gripped portion of the target in consideration of the position change, and interpolating the information obtained from the proximity sensor in the manipulator control cycle, and interpolating this interpolated information Based on this information, the relative position and speed of the target to be gripped are generated, and based on this information, the manipulator is driven to position the gripper at a grippable position of the target to be gripped, and the target is moved by the gripper. And the step of capturing.

Therefore, the manipulator can be operated smoothly by interpolating the information from the inertia sensor, the visual sensor, and the proximity sensor in the control cycle of the manipulator control device. can do.

[0018]

An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows the appearance of a space robot 21 controlled by a robot controller according to one embodiment of the present invention.

The space robot 21 includes an artificial satellite 22 and a manipulator 23 mounted on the artificial satellite 22.

The artificial satellite 22 has an inertial sensor 24 for detecting the position and speed of the artificial satellite 22, and a position and speed for recognizing a relative position between a target (not shown) to be captured and the artificial satellite 22. Visual sensor 25 and a propulsion device 26 for controlling the flight and attitude of the artificial satellite 22
a, 26b, 26c.

On the other hand, at the tip of the manipulator 23,
A gripper 27 is attached. This gripper 27
A force sensor 28 for detecting a force applied to the gripper 27 and a proximity sensor 29 for detecting a relative position and speed between the gripper 27 and a target (not shown) are mounted in the vicinity of.

As shown in FIG. 2, a control system 31 for starting operation by an external radio signal is provided inside the artificial satellite 22, and this control system 31 is provided between the artificial satellite and the manipulator. It is connected to the dynamics 32.

The control system 31 includes a target position / speed interpolator 39 for interpolating the position and orientation of the target detected by the visual sensor 25 or the proximity sensor 29 in the control cycle of the manipulator, and the position, orientation and speed of the target. Manipulator trajectory generator 33 that generates a trajectory of the tip of manipulator 23 from, a trajectory of manipulator 23, force information acting on manipulator 23, artificial satellite 2
Input the translation, rotation speed, etc. of the manipulator 23
Manipulator tip speed generator 3 for generating tip speed
4, a manipulator joint speed generator 35 for generating the joint speed of the manipulator 23 from the tip speed of the manipulator 23, and a Jacobian matrix generator 36 for generating a Jacobian matrix from the joint angles of the manipulator 23 and providing the same to the manipulator joint speed generator 35 A coordinate converter 37 for inputting the joint angle of the manipulator 23, the position and attitude of the artificial satellite 22, and generating the tip position of the manipulator 23 in a coordinate system fixed in outer space; and the position and attitude of the artificial satellite 22 A body position / velocity interpolator 40 for inputting information and generating the position and attitude of the body of the artificial satellite 22; a coordinate system fixed to space from the position and attitude of the body of the artificial satellite and the joint angle of the manipulator; And a rotation matrix generator 38 that generates a rotation matrix between coordinate systems.

When the space robot 21 captures a flight target, first, the visual sensor 2 mounted on the artificial satellite 22 is used.
In step 5, the relative position and speed with respect to the target are recognized.
Based on this recognition result, the target is the space robot 21
The space robot is guided toward the target by operating the propulsion devices 26a to 26c so as to be within the operation range of the manipulator 23 mounted on the target.

Next, changes in the position and speed of the artificial satellite 22 accompanying the operation of the manipulator 23 are detected by an inertial sensor 24 mounted on the artificial satellite 22. And artificial satellite 22
The manipulator 23 is moved so that the gripper 27 is located at the position to be gripped by the target (not shown) while taking into account the change in the position.

The control of the manipulator 23 is specifically performed as follows.

That is, in the outer space, the gripper 2
The target position / velocity interpolator 39 generates a trajectory interpolated in the control cycle of the manipulator 22 from the current position 7 to the position of the gripped portion of the target (not shown). Based on this, the manipulator trajectory generator 33 generates a sequential target value ^A P _m ^d in the coordinate sigma _A fixed in space. At that time, the sequential target value ^A P
the current position of the manipulator 23 in _m ^d and space
From ^A P _m ^m, the manipulator tip velocity generator 34 to calculate the following values by the PID control. That is, the use of tip speed command value ^A V _m ^d of the manipulator 23, the translation of the artificial satellite 22 in the coordinate system sigma _A interpolated in the control cycle of the manipulator 23 at the body position and velocity interpolator 40 is detected by the inertial sensor 24 using the velocity ^a V _C ^m and the rotational angular velocity _{^{ω C m, C V m d}} = C T a · (a V m d - a V C m) -C · C P m m · ω C m (1) According to the equation, a coordinate system fixedly provided on the artificial satellite 22 Σ
calculating the tip velocity ^C V _m ^d of the manipulator 23 in _c. However, the ^C T _A, a rotation matrix for converting the coordinate system Σc fixed to the satellite 22 to the fixed coordinate system sigma _A in space. This rotation matrix ^C T _A is
2 is interpolated from the position of the main body by the main body position / velocity interpolator 40 in the control cycle of the manipulator 23, and the rotation matrix generator 3
8 is generated. C is a constant conversion matrix.

Then, the manipulator joint velocity generator 3
In 5, the _{^{ω m d = J -1 · C}} V m d (2), the speed command value for each joint of the manipulator 23 omega _m
^d is obtained, and each axis motor of the manipulator 23 is driven.

Here, J is the Jacobian matrix of the manipulator, which is calculated by the Jacobian matrix generator 36 using the joint angle information of the manipulator.

After reaching the target gripping position, the relative velocity ^C V _t ^m between the gripper 27 and the target (not shown) detected by the proximity sensor 29 and interpolated by the target position / velocity interpolator 39 in the control cycle of the manipulator.
Using, in the manipulator tip velocity generator 34 generates the manipulator tip speed command value ^C V _m ^d. That is, the (k-1) th and successive target position ^C P _m ^d of the end of the arm in the control period of the k-th [k], ^C P _m
^d [k-1], and the relationship of the arm tip speed command value _{^{C V m d, C P m}} d [k] = C P m d [k-1] + C V m d · t 0 (3) C V _{^{m d = G p · (C}} P t d [k-1] - C P m d [k-1]) + from ^C V _t ^m (4), to produce a tip speed command value ^C V _m ^d. Furthermore, the manipulator joint velocity generator 35, by the equation (2), and generates a speed command value omega _m ^d of each joint of the manipulator 23 to drive the motors of the respective axes.

Further, when the gripper 27 grips the target gripping portion of the target (not shown), the manipulator tip speed generator 34 assumes a tamper (viscosity damping coefficient C) having a dead zone at the tip position of the manipulator 23, This produces a tip speed ^C V _m ^d of as the manipulator 23 detected force F at the force sensor 28 attached to the manipulator 23 is the same movement and in the case of action. Then, the gripper 27 of the gripped portion of the target
Swing of the target due to contact with the target.

[0033] That is, the force information F detected by the force sensor 28, the set value F _a preset force, using a viscous damping coefficient C, and when the F> F _a is, ^C V _m ^d = when the _{^{C -1 · (F-F a}} ) (5) F ≦ F a is the ^{_{C V m d = 0 (6}} ), determine the tip speed ^C V _m ^d of the manipulator 23. Then, in the manipulator joint velocity generator 35 uses this value, obtain a speed command value omega _m ^d of each joint of the manipulator 23 to drive the motors of the respective axes of the manipulator 23. Then, the operation is finally shifted to the gripping operation.

As described above, the relative position between the target to be captured by the visual sensor 25 and the space robot 21,
Recognizing the speed, the space robot body is made to track the target based on the information obtained by the visual sensor 25 and interpolated by the target position / speed interpolator 39 in the control cycle of the manipulator 23. Thereafter, the proximity sensor 29 detects the relative position and speed between the grasped portion of the target and the tip of the manipulator of the space robot 21, and information obtained by interpolating this information in the control cycle of the manipulator 23 by the target position / speed interpolator 39. Based on the above, the manipulator tip position obtained by the proximity sensor 29 is tracked to the target. Next, a target speed at the tip of the manipulator 23 is generated in consideration of a change in the attitude of the artificial satellite 22 accompanying the operation of the manipulator 23, and the tip of the manipulator 23 is positioned, thereby performing a tracking operation on the flying target. Further, a force acting between the gripped portion of the target and the gripper 27 detected by the force sensor 28 is detected, and the manipulator 23 is controlled using this information. In this manner, since the swing of the target accompanying the capture is reduced, the capture operation of the flying target can be performed stably.

In the above embodiment, an artificial satellite is used as the robot body. However, the present invention is not limited to this, and a diving body such as a diving robot floating in water may be used.

[0036]

As described above, in the robot control apparatus according to the present invention, the inertial sensor and the visual sensor mounted on the robot body for detecting the position and speed of the robot body, the gripper and the target of the manipulator are provided. A proximity sensor mounted on the manipulator to detect a relative position and orientation with respect to the body, a main body position / velocity interpolating means for interpolating information obtained from the inertial sensor at a control cycle of the manipulator, and a visual sensor In order to track the robot body to the target based on the information obtained from the robot, the visual sensor information is interpolated at the control cycle of the manipulator, and the gripped part of the target can be gripped based on the information obtained from the proximity sensor. To interpolate the information of the proximity sensor at the control cycle of the manipulator to position the gripper at the position. Target position / velocity interpolation means, the manipulator can move smoothly even if it takes time to process information from the visual sensor and the proximity sensor, and the target can be stably captured. Becomes possible.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an artificial satellite according to the present invention.

FIG. 2 is a block diagram showing a control device of the artificial satellite according to the present invention.

FIG. 3 is a block diagram showing a conventional artificial satellite control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 21 Space robot 22 Artificial satellite 23 Manipulator 24 Inertial sensor 25 Visual sensor 27 Gripper 28 Force sensor 29 Proximity sensor 39 Target position / velocity interpolator 40 Body position / velocity interpolator

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁶ Identification code FI G05B 19/4103 G05D 3/12 K G05D 3/12 1/08 A G05B 19/18 D // G05D 1/08 19/415 D

Claims (4)

[Claims] 1. A robot controller for controlling a robot having a robot main body and a manipulator mounted on the robot main body so that the robot can capture a floating target. An inertial sensor mounted on the robot main body to detect the position and speed of the main body, a relative position between the robot main body and the target, a visual sensor to detect a speed, the gripper of the manipulator and the target, A proximity sensor mounted on the manipulator to detect the relative position and speed of the main body, and a main body position / speed interpolation unit for interpolating information obtained from the inertial sensor at a control cycle of the manipulator, The robot body tracks the target based on information obtained from the visual sensor. In addition, the visual sensor information is interpolated in a control cycle of the manipulator, and the proximity is performed so that the gripper is located at a position where the gripped portion of the target can be gripped based on the information obtained from the proximity sensor. A control device for a robot, comprising: target position / velocity interpolation means for interpolating sensor information at a control cycle of the manipulator. 2. The method according to claim 1, wherein the visual sensor mounted on the robot body also has a function of a proximity sensor for recognizing a relative position and a speed between a gripped portion of the target and the gripper at the tip of the manipulator. The control device for a robot according to claim 1, wherein 3. The robot according to claim 1, wherein the proximity sensor mounted on the manipulator also has a function of a visual sensor for recognizing a relative position and a speed between the target and the robot body. Control device. 4. An inertial sensor mounted on the robot body for detecting the position and speed of the robot body, and the robot body for detecting a relative position and speed between the robot body and a target to be captured. A robot control method comprising: a mounted visual sensor; and a proximity sensor mounted on the manipulator for detecting a relative position / velocity between a gripper of the manipulator provided on the robot body and the target. The information obtained from the visual sensor is interpolated in the control cycle of the manipulator, and based on the interpolated information, the trajectory of the robot body such that the tip of the manipulator coincides with the gripped portion of the target. Then, a drive command is generated, and the propulsion device of the robot body is driven so as to track the target. Moving, the position of the robot body accompanying the operation of the manipulator,
Posture change is detected by the inertial sensor, the detected information is interpolated in the control cycle of the manipulator, and based on the interpolated information, the tip of the manipulator is considered in consideration of a change in the position of the robot body. Driving the manipulator to position the target on the grasped portion of the target; and interpolating information obtained from the proximity sensor in the manipulator control cycle, and based on the interpolated information, A relative position with respect to the gripped portion, a speed is generated, and based on this information, the manipulator is driven to position the gripper at a grippable position of the gripped portion of the target, and the target is moved by the gripper. Capturing the robot.