JP2006341341A - Contact sensor system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a contact sensor system, making a contact sensor to efficiently function to thereby detect a contact with an object in a short time and with good accuracy. <P>SOLUTION: This contact sensor system 1 includes: a contact sensor 2 installed in a contact part probably coming into contact with the object W with the movement of a movable robot to detect the contact with the object W; an object information obtaining means 3 for obtaining the information on the object W; a movement plan means 4 for planning the movement of the movable robot; an actual contact part estimating means 5 for estimating the actual contact part having high possibility of coming into contact with the object in the contact part; and a sensitivity adjusting means 6 for making the detecting accuracy of the contact sensor in the actual contact part higher than that of the other parts. The detecting accuracy of the actual contact part having high possibility of coming into contact with the object W with the movement of the movable robot is thus made higher than that of the other parts, whereby the contact with the object W can be detected in a short time with good accuracy. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a system using a contact sensor that detects contact with an object. More specifically, the present invention relates to a contact sensor system for efficiently functioning a contact sensor installed at a contact site that may come into contact with an object with the operation of a movable robot.

  There is a demand for accurately detecting the presence / absence of contact and the contact state of a part that may contact an object (hereinafter referred to as a contact part). Therefore, there have been proposals for a contact sensor that detects contact with an object. As a contact sensor, a pressure detection type sensor that detects a contact state based on a pressure generated by contact of an object is widely used. For example, Patent Document 1 discloses that a plurality of row electrodes arranged substantially in parallel and a plurality of column electrodes arranged substantially in parallel are overlapped with each other via a pressure-sensitive ink layer so that the intersection of the electrodes is a plurality of pressure detection units. A pressure distribution sensor is disclosed. When such a pressure distribution sensor is used, the contact state with the object can be confirmed based on outputs from a plurality of pressure detection units.

  By the way, in recent years, robot-related technology has evolved at a remarkable speed. In manufacturing factories and the like, many robots that repeat predetermined tasks are employed, and high-accuracy robots that are anthropomorphic to the appearance and can perform complex tasks according to the situation are provided. For example, one of basic operations performed by a robot is an operation of grasping and moving an object. If the contact sensor is incorporated in the gripping portion of the robot that performs the gripping operation in this way, it is possible to confirm the contact with the object and perform the gripping operation accurately.

  In addition, it is assumed that a mobile robot having a function of moving the position will frequently encounter obstacles such as walls and people when moving. If the contact state can be accurately confirmed when the robot collides with an object, it can be used for control of the robot after the collision. Therefore, in the case of such a mobile robot, it is desirable that a contact sensor be installed on the outer skin (outer cover) so that the presence or absence of contact can be confirmed.

Japanese Patent Laid-Open No. 11-118635

  If a part that has multiple pressure detectors, such as the pressure distribution sensor described above, is used for the contact part that may come into contact with the object as the movable robot moves, the contact state with the object can be accurately determined. I can grasp. However, when a pressure distribution sensor is used, since a configuration in which a large number of pressure detection units are scanned one by one is common, the detection time becomes long if the number of pressure detection units is large. On the other hand, sensing is often performed with the same sensitivity, including a pressure detection unit in a region where there is no possibility of contact with an object. Sensing to such an unnecessary part consumes energy and time and is inefficient. For example, in a situation where you want to check the contact with an object in a short time to deal with a collision caused by the movement of the robot, if the sensing process takes a long time and exceeds a certain time, the contact sensor It also loses the significance of installing and detecting contact.

  Accordingly, an object of the present invention is to provide a contact sensor system that allows a contact sensor to function efficiently and to detect contact with an object accompanying the operation of a movable robot in a short time with high accuracy.

  The object is to provide a contact sensor for detecting contact with the object, and an object information acquisition means for obtaining information on the object, which is installed at a contact part that may come into contact with the object in accordance with the movement of the movable robot. , An operation planning means for planning the operation of the movable robot, and an actual contact site that is likely to contact the object among the contact sites based on the information on the object and the motion plan. This can be achieved by a contact sensor system comprising a contact site prediction unit and a sensitivity adjustment unit that increases the detection accuracy of the contact sensor at the actual contact site as compared with other sites.

  The contact sensor system of the present invention can detect the contact with the object with high accuracy in a short time because the detection accuracy of the actual contact portion where the sensitivity adjusting means is likely to contact the object is higher than that of other portions.

  Further, the motion plan is a motion plan for gripping the object of the movable robot, and the contact portion is a portion that may come into contact with the object when the movable robot grips the object. can do. In this case, when the movable robot performs an operation of gripping the object, it can be used to surely grip the object to be gripped.

The motion plan is a motion plan for the movable robot to move,
The contact part may be a part that may come into contact with the object when the movable robot moves. In this case, when the movable robot performs the moving operation, it can be used for confirming that the object has come into contact with the object in a short time and taking necessary measures.

  In addition, the sensitivity adjustment unit may adjust the detection accuracy by changing a detection cycle or a detection resolution of the contact sensor. When changing the detection cycle (detection frequency), the cycle of the actual contact portion may be set higher than that of other portions. In addition, when changing the detection resolution, all the detection points of the actual contact part may be made active and a part of the detection points of other parts may be paused.

  The contact sensor may be a distributed pressure sensor including a plurality of pressure detection units. Since the distributed pressure sensor can set many detection points, it is effective for detecting contact with an object with high accuracy.

  A movable robot equipped with the above contact sensor system can detect contact with an object in a short time and with high sensitivity. Therefore, the detection result can be used to perform necessary operations (for example, gripping, collision avoidance, collision handling, walking, etc.) ) Can be executed smoothly.

  ADVANTAGE OF THE INVENTION According to this invention, a contact sensor system which functions a contact sensor efficiently and can detect the contact with the object accompanying operation | movement of a movable robot accurately in a short time can be provided.

  Hereinafter, a contact sensor system according to an embodiment of the present invention will be described. In addition, this contact sensor system is a sensor system for installing a contact sensor in a contact part that may come into contact with an object in accordance with the operation of the movable robot and efficiently using the output from the contact sensor. . The configuration included in the contact sensor system of the present invention will be described with reference to the drawings. FIG. 1 is a functional block diagram showing a main part configuration of the contact sensor system 1. The contact sensor system 1 includes a contact sensor 2, an object information acquisition unit 3, an operation plan unit 4, an actual contact site prediction unit 5, and a sensitivity adjustment unit 6.

  The contact sensor 2 includes a plurality of contact detection points, and outputs a contact detection signal at a level corresponding to the contact pressure from the contact detection point where contact with the object has occurred. As the contact sensor 2, for example, a distributed pressure sensor (also referred to as a pressure distribution sensor) including a plurality of pressure detection units can be employed. The contact sensor 2 is installed at a portion that may come into contact with the object W. More specifically, a part that may come into contact with the object W in accordance with the movement of the movable robot is set in advance as a contact part, and a contact sensor 2 is installed to confirm the presence or absence of actual contact at the contact part. ing. Specifically, the contact part is, for example, a gripping part (part corresponding to a palm) that grips an object with a robot hand, or a peripheral object (equipment, material, person, etc.) within the skin (outer cover) of a position-moving type robot ). Furthermore, in the case of a walking robot, the foot part can be used as a contact site with a sidewalk or staircase as an object.

  The object information acquisition unit 3 is a unit that acquires information related to the object W that may come into contact. As the object information acquisition means 3, for example, a three-dimensional (3D) stereo camera or a laser range finder that can recognize the position and shape of the object W can be employed.

  The operation planning means 4 is means for planning the operation of the movable robot. That is, the motion planning means 4 plans the motion of the movable robot to which the contact sensor system 1 is applied. For example, when the robot grips an object, the motion planning unit 4 plans a moving operation for moving the robot's hand unit to a gripping position (grip position) and a gripping operation executed at the gripping position.

  The actual contact site prediction means 5 is highly likely to come into contact with the object W within the contact site based on the information related to the object W from the object information acquisition means 3 and the motion plan planned by the motion planning means 4. Predict actual contact area. For example, the actual contact site prediction unit 5 determines which region of the gripping part actually contacts the object W when the gripping operation is performed at the gripping position planned by the motion planning unit 4 or the surface of the position-moving robot. The actual contact portion is set by predicting which region actually collides with the object and which region of the sole part of the walking robot actually contacts the sidewalk or the like.

  And the sensitivity adjustment means 6 sets the detection accuracy of the contact sensor 2 in the said actual contact site | part high compared with another site | part. The sensitivity adjustment unit 6 sets, for example, the detection cycle or detection resolution of the actual contact site higher than that of other sites. Therefore, when the contact sensor 2 actually contacts the object W, a highly sensitive contact detection signal is output from the actual contact portion. Thus, by limiting the range of the contact sensor to be sensed (scanned) to a portion that is highly likely to contact the object W, the contact with the object W can be detected in a short time and with high accuracy.

  Further, in the following, embodiments in which the above contact sensor system is applied to various movable robots will be described.

  The first embodiment is an example where the contact sensor system 1 is applied to a movable robot having a function of gripping an object. FIG. 2 is a diagram schematically illustrating a state in which the robot 10 grips the cup CP as an object to be gripped, and FIG. 3 is a functional block diagram of the robot 10.

  As shown in FIG. 2, the robot 10 has an anthropomorphic form. A robot hand device 11 is attached to the main body 10BD of the robot 10. The robot hand device 11 includes a gripping portion 12 having an object gripping function on the distal end side. The robot hand device 11 is driven by a joint mechanism or actuator (not shown) to perform a predetermined operation. FIG. 2 shows a state where the robot 10 grips the cup CP on the table TA and moves it to another position.

  On the grip surface side (inside) of the grip portion 12, a distributed pressure sensor 13 is provided on the entire surface as shown in an enlarged manner in a circle CR. In the head 10HD of the robot 10, a 3D stereo camera 14 for checking the position and shape of the cup CP (object W) to be grasped is embedded. Further, the head 10HD is provided with a microcomputer 15 (hereinafter referred to as a microcomputer 15) formed around a CPU (Central Processing Unit) that controls the operation of the robot 10 as a whole. The microcomputer 15 acquires information on the cup CP from the 3D stereo camera 14, and performs drive control of the robot hand device 11 and sensitivity adjustment of the distributed pressure sensor 13.

  FIG. 3 is a functional block diagram illustrating the main configuration of the robot 10 according to the first embodiment. FIG. 3 is shown corresponding to FIG. 1 (a block diagram of the contact sensor system 1) shown above. As shown in FIG. 3, in the first embodiment, the object information acquisition unit 3 is realized as a 3D stereo camera, and the contact sensor 2 is realized as a distributed pressure sensor 13. Further, the operation planning unit 4, the actual contact site prediction unit 5, and the sensitivity adjustment unit 6 are realized by the microcomputer 15. A ROM (Read Only Memory) 16 and a RAM (Random Access Memory) 17 are connected to the microcomputer 15 via a bus 18. The ROM 16 stores a program for controlling the driving of the robot 10 and data related thereto. In particular, the program stored in the ROM 16 includes a control program for increasing the detection accuracy of the actual contact portion described above when the robot hand device 11 is driven to perform the operation of gripping the cup CP (object W). The RAM 17 provides a processing area when the microcomputer 15 reads a program from the ROM 16 and executes control.

  FIG. 4 is a flowchart showing an example of a routine that is executed when the microcomputer 15 performs the gripping operation of the cup CP. The microcomputer 15 acquires image information related to the cup CP to be grasped from the 3D stereo camera 14 (S101), and confirms the position and shape of the cup CP (S102). Here, the microcomputer 15 moves the robot hand device 11 to a gripping position where the cup CP can be gripped based on the standby position of the robot hand device 11 and the position of the cup CP, and further grips the cup CP by the grip portion 12. Is planned (S103).

  Further, as schematically shown in FIG. 2 surrounded by the balloon BA, the microcomputer 15 is provided with the distributed pressure sensor 13 when the gripper 12 performs the gripping operation at the planned gripping position. Of the contact parts, a part (actual contact part) that is likely to actually contact the cup CP is predicted (S104). Then, the sensitivity of the distributed pressure sensor 13 existing at the actual contact portion is changed to be higher than that of the other portions (S105), and the processing according to this routine ends.

  When the microcomputer 15 executes the above routine along with the gripping operation of the cup CP, the contact can be detected with high accuracy when the cup CP is actually gripped by the grip portion 12. In addition, since the sensitivity is increased only in the region where there is a possibility of contact with the cup CP in the distributed pressure sensor 13, the cup CP can be shortened in a shorter time compared to the case where the entire distributed pressure sensor is sensed as in the past. Can be completed. Therefore, the robot 10 to which the contact sensor system 1 of the first embodiment is applied can reliably detect the cup CP and accurately hold it.

  Next, Example 2 will be described. The second embodiment is an example in which the above-described contact sensor system 1 is applied to a position movement type robot 20 having a function to cope with a possibility of collision with an object. FIG. 5 is a diagram schematically illustrating an example of a state where the robot 20 may collide with an object. FIG. 5A illustrates a case where the robot 20 may collide with the wall WA, and FIG. It shows when there is a possibility of collision with an approaching person HU. Although the robot 20 is shown in a simplified manner in the second embodiment, the head 20HD is provided with a 3D stereo camera and a microcomputer as in the robot 10 of the first embodiment. The difference from the first embodiment is that a distributed pressure sensor is installed on the outer skin (outer cover) 21.

  In the robot 20, a distributed pressure sensor is disposed on substantially the entire outer skin 21. The head 20HD has a stereo camera. As shown in FIG. 5A, when the wall WA is confirmed on the left side while the robot 20 is moving, the microcomputer increases the sensitivity of the left pressure sensor 13L. Therefore, when the robot 20 collides with the wall WA, it is possible to detect with high sensitivity and take measures after the collision.

  FIG. 5B shows a case where an obstacle (in the illustrated example, a human HU) approaches from the front side of the robot 20. In this case, the sensitivity of the pressure sensor 13F on the front side where the possibility of collision is high is increased. Therefore, when the robot 20 collides with the human HU, this can be detected with high sensitivity to cope with the situation after the collision.

  In the case of the first embodiment, by incorporating the contact sensor system 1 into the robot 10 that performs the gripping operation, the cup CP that is the gripping target can be accurately detected and gripped reliably. That is, in the case of the first embodiment, the contact sensor system 1 performs an auxiliary function in performing an active operation performed by the robot 10. On the other hand, in the case of the second embodiment, an operation in which the microcomputer of the robot 20 moves from one position to another position is planned, and an unexpected obstacle appears when this is executed. is there. That is, in the case of the second embodiment, there is a possibility that the robot 20 may collide with an obstacle when the robot 20 operates according to the operation plan, and the contact sensor system 1 performs an auxiliary function as a collision countermeasure operation.

  Further, Example 3 will be described. The third embodiment is an example in which the above-described contact sensor system 1 is applied to a robot having an autonomous walking function. FIG. 6 is a diagram schematically showing how the robot 30 walks. Similar to the robots 10 and 20 described above, the robot 30 has anthropomorphic form and includes a microcomputer, but FIG. 6 shows only the leg portion.

  In the robot 30, the distributed pressure sensor 13 is provided on the entire sole 31 as in the first embodiment. In addition, external sensors (for example, CCD sensors) 32 are disposed at the four corners of the foot sole portion 31 so that the distance between the footpath RD and the foot sole portion 31 and the state of the footpath surface can be confirmed. That is, in the third embodiment, the contacting object is a sidewalk, and the sole part 31 of the robot 30 is a contact part. The CCD sensor 32 corresponds to the 3D stereo camera in the first and second embodiments.

  When the microcomputer of the robot 30 confirms the sidewalk RD by the external sensor 32 of the sole 31 to be stepped on, the portion of the distributed pressure sensor 13 provided on the sole 31 is likely to actually contact the sidewalk. Increase sensitivity. Here, since the heel part 31B of the sole 31 comes into contact with the sidewalk RD first, the sensitivity of the pressure sensor 13 is increased using this heel part 31B as an actual contact part. Therefore, when the robot 30 comes into contact with the sidewalk RD, the state of the sidewalk RD can be detected with high sensitivity and can be used for subsequent control (for example, posture control of the robot 30). Here, the sidewalk RD is taken as an example, but the same applies when the robot 30 goes up the stairs.

  In the case of the third embodiment, by incorporating the contact sensor system 1 into the robot 30 that performs the walking motion, the sidewalk RD that is the walking target can be detected with high accuracy and can be reliably walked. That is, as in the case of the first embodiment, the contact sensor system 1 performs an auxiliary function in performing an active operation performed by the robot.

  In the second and third embodiments, the microcomputer (not shown) mounted on the robots 20 and 30 recognizes the target object, and the object (wall, person, sidewalk) is actually detected in the distributed pressure sensor 13. ) Is executed to change the contact detection unit existing in the actual contact portion that may come into contact with high sensitivity. Since this process is the same as that of the flowchart of FIG.

  As is apparent from the above description, the robots 10, 20, and 30 according to the embodiment to which the contact sensor system is applied can detect the target object in a short time with high sensitivity. In the above embodiment, a distributed pressure sensor is used as an example of a contact sensor, but the present invention is not limited to this. Other types of contact sensors can be used in the same manner as long as they have a plurality of contact detection points and detect contact with an object.

  Although the preferred embodiments of the present invention have been described in detail above, the present invention is not limited to the specific embodiments, and various modifications and changes can be made within the scope of the gist of the present invention described in the claims. It can be changed.

It is the functional block diagram which showed the principal part structure of the contact sensor system of embodiment. It is the figure which showed typically a mode when the robot of Example 1 hold | grips a cup as an object of a holding object. FIG. 3 is a functional block diagram of the robot according to the first embodiment. 6 is a flowchart illustrating an example of a routine that is executed when the microcomputer of the robot according to the first embodiment performs a gripping operation of the cup. It is the figure which showed an example of the state with which the robot of Example 2 may collide with an object typically, (A) is a possibility of colliding with a wall, (B) is the approaching person and It shows when there is a possibility of collision. It is the figure which showed typically a mode that the robot of Example 3 walked.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Contact sensor system 2 Object information acquisition means 3 Contact sensor 4 Motion planning means 5 Actual contact site prediction means 6 Sensitivity adjustment means 10, 20, 30 Robot 12 Gripping part 13 Distributed pressure sensor (contact sensor)
14 3D stereo camera (object information acquisition means)
15 Microcomputer
(Operation planning means, actual contact site prediction means, sensitivity adjustment means)
W object CP cup (object)

Claims (5)

A contact sensor that is installed at a contact portion that may come into contact with an object in accordance with the movement of the movable robot, and detects contact with the object;
Object information obtaining means for obtaining information of the object;
Motion planning means for planning the motion of the movable robot;
Based on the information on the object and the operation plan, an actual contact site prediction unit that predicts an actual contact site that is likely to contact the object among the contact sites;
A contact sensor system comprising: a sensitivity adjustment unit that increases detection accuracy of the contact sensor at the actual contact part as compared with other parts. The motion plan is a motion plan for gripping the object of the movable robot,
The contact sensor system according to claim 1, wherein the contact part is a part that may come into contact with the object when the movable robot grips the object. The motion plan is a motion plan for the movable robot to move,
The contact sensor system according to claim 1, wherein the contact part is a part that may come into contact with the object when the movable robot moves. The contact sensor system according to claim 1, wherein the sensitivity adjustment unit adjusts the detection accuracy by changing a detection cycle or a detection resolution of the contact sensor. The contact sensor system according to claim 1, wherein the contact sensor is a distributed pressure sensor having a plurality of pressure detection units.

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