JP7224843B2 - Robot, transport vehicle equipped with this robot, control method and control program for this robot - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a robot, a transport vehicle equipped with this robot, and a control method and control program for this robot.

2. Description of the Related Art Conventionally, robots are known that can accurately perform work based on information about an object. For example, in Patent Document 1, an arm is provided, and a predetermined area within an imaging area that can be imaged by an imaging unit provided on the arm is the above-mentioned The imaged image in which the object is imaged by the imaging unit at the position that matches the image area including the object or an area smaller than the image area in the image area of the imaged image imaged by the imaging unit. is described as a robot that detects information about the object based on and grips the object based on the detected information. In this robot, an image of a captured image captured by the imaging unit when the arm is moved to a position where each of a plurality of objects is captured in a predetermined area within an imaging area that can be captured by the imaging unit provided on the arm. Information about an object based on a captured image in which the object is captured by an imaging unit at a position where each of a plurality of objects is captured, the image area including the object or an area smaller than the image area of the area. is detected and the object is gripped based on the detected information, it is possible to accurately perform the work based on the information about the object.

JP 2018-34243 A

However, in the robot described in Patent Document 1, since only the information about the object is obtained using the imaging means, the arm cannot move in a predetermined manner due to the presence of obstacles or the like in the movement path of the arm. In some cases, there is a problem that the movement of the arm may be hindered, the arm may be damaged, or the arm may not be able to move to the position of the object. In addition, when performing a shift operation to cope with a change in the position of an object, the movement path of the arm differs from the predetermined path, so the movement of the arm is hindered and the arm may be damaged. , there is a problem that the possibility of being unable to move to the position of the object increases.

The present invention has been made in view of such problems, and by detecting an obstacle that hinders the movement of the arm, it is possible to prevent the arm from colliding or breaking, and move the object more reliably. The main purpose is to provide a robot that can Another object of the present invention is to provide a transport vehicle equipped with this robot that can reliably transport an object.

The present invention employs the following means to achieve at least one of the above objects.

The robot of the present invention is
A robot equipped with an arm having a moving part for moving an object,
an imaging means for imaging an area including the arm and acquiring imaging information including an arm area corresponding to the arm;
In the photographing information, it is determined whether or not the distance between the obstacle area corresponding to the obstacle and the arm area is within a predetermined approach range. control means for regulating movement of the arm;
characterized by comprising
It is.

This robot includes an imaging means for imaging an area including an arm, and a control means for controlling movement of the arm. Movement of the arm is controlled by the control means, and a moving section moves an object. At this time, the photographing means obtains photographing information by photographing an area including the arm, and the arm area corresponding to the arm and the obstacle area corresponding to the obstacle included in the photographing information are within a predetermined proximity range. The control unit determines whether or not the arm is within the proximity range, and restricts the movement of the arm when it is determined that the arm is within the proximity range. By doing so, the distance between the arm and the obstacle can be kept larger than the predetermined proximity range, so the possibility of collision between the arm and the obstacle can be reduced.

The robot of the present invention includes reference information obtained by photographing an area including the arm area in advance, and the control means compares the reference information and the photographing information to determine whether the obstacle area is included in the photographing information. If it is determined that the obstacle area is included in the photographing information, it is determined whether or not the distance between the obstacle area and the arm area is within the approach range. , the movement of the arm may be restricted when it is determined that the arm is within the approach range. By comparing the photographing information and the reference information in this manner, it is possible to easily determine whether or not an obstacle area corresponding to an obstacle exists in the photographing information. In addition, by more reliably determining the presence or absence of an obstacle, it is possible to further reduce the possibility of contact between the obstacle and the arm.

In the robot of the present invention, when the control means determines that the moving area corresponding to the moving part is positioned between the obstacle area and the lowest part of the arm in the photographing information, It may be characterized by regulating movement. By doing so, it is possible to reduce the possibility that the moving part will be positioned between the obstacle and the lowest part of the arm. In addition, since the moving part is provided at the tip of the arm, if the moving part is positioned between the obstacle and the lowest part of the arm, there is a high possibility that the arm will come into contact with the obstacle. Therefore, by reducing the possibility that the moving part will be positioned between the obstacle and the lowermost part of the arm, the possibility of contact between the arm and the obstacle can be reduced.

In the robot of the present invention, the moving part may have a feature point that becomes a feature when being photographed by the photographing means. In this way, when the photographing information is analyzed, by providing the moving part with a feature point that can be easily extracted, the moving part can be easily extracted as compared with the case where the feature point is not provided.

In the robot of the present invention, the photographing means may acquire the photographing information multiple times at photographing intervals determined based on the movement speed of the arm. Specifically, for example, when the movement speed of the arm is fast, the number of times of photographing information is acquired by increasing the number of times of photographing per unit time. The number of acquisitions of imaging information may be reduced by reducing the number of imagings. By doing so, it is possible to reduce the possibility that the distance between the arm and the obstacle will come closer than the approach range, reduce the possibility that the arm and the obstacle will come into contact with each other, and reduce the number of times of photographing. can reduce the amount of processing.

The transport vehicle of the present invention is
A carrier equipped with the robot according to any one of the above,
A plurality of the photographing means are provided at a position for photographing the area including the robot from above,
It is.

Since this transport vehicle includes the above-described robot as part of its configuration, it has the same effects as the above-described robot, for example, the distance between the arm and the obstacle can be kept wider than the predetermined proximity range. An effect is obtained in that the possibility of contact between the arm and the obstacle can be reduced in advance.

The robot control method of the present invention includes:
an imaging means for imaging an area including an arm and acquiring imaging information including an arm area corresponding to the arm; and a distance between an obstacle area corresponding to an obstacle and the arm area is predetermined in the imaging information. determining whether or not the object is within the approach range, and if it is determined that the object is within the approach range, an arm having a moving part for moving the object; A control method for controlling a robot comprising
a photographing step of acquiring the photographing information;
In the photographing information, it is determined whether or not the distance between the obstacle area corresponding to the obstacle and the arm area is within a predetermined approach range. a regulating step of regulating movement of the arm;
characterized by comprising
It is.

A robot control method of the present invention includes imaging means for imaging an area including an arm, and control means for controlling movement of the arm. do. At this time, the photographing means obtains photographing information by photographing an area including the arm, and whether the arm area corresponding to the arm and the obstacle area corresponding to the obstacle included in the photographing information are within a proximity range in advance. If it is determined that it is within the proximity range, the movement of the arm is restricted. By doing so, the distance between the arm and the obstacle can be kept longer than the predetermined proximity range, so the possibility of contact between the arm and the obstacle can be reduced.

A program of the present invention is a program for causing one or more computers to execute each step of a robot control method. This program may be recorded on a computer-readable storage medium (for example, hard disk, ROM, CD, DVD, flash memory, etc.), or may be recorded on a transmission medium (communication network such as the Internet or wired/wireless LAN). It may be sent from one computer to another via a computer, or sent or received in any other manner. Moreover, even if each step of the control method is executed by a device, the device that executes the program and the device that executes the process may be different. In either case, the same effect as the control method described above can be obtained by causing one computer to execute this program or by causing a plurality of computers to share and execute each step.

FIG. 1 is a side view showing an outline of the configuration of the transport vehicle 20. FIG. FIG. 2 is a rear view showing the outline of the configuration of the carrier 20. As shown in FIG. FIG. 3 is a block diagram for explaining the electrical connection of the carrier 20. As shown in FIG. FIG. 4 is a flow chart showing an example of a movement control processing routine.

Next, the carrier 20 including the robot 30 will be described in detail as an example of an embodiment of the present invention. The embodiments and drawings described below illustrate a part of the embodiments of the present invention, and are not used for the purpose of limiting to these configurations, and within the scope of the gist of the present invention It can be changed as appropriate. The same or similar reference numerals are given to corresponding components in each figure. In addition, by showing an example of the control method of the carrier 20 including the robot 30, an example of the robot control method and the control program of the present invention will also be clarified.

As shown in FIGS. 1 and 2, a guided vehicle 20, which is an example of an embodiment of the present invention, has a robot 30 and is an unmanned automated guided vehicle capable of self-propelled along a predetermined route. The robot 30 automatically travels along a predetermined route according to communication or a predetermined transport route, and loads and unloads objects with the robot 30 . In this transport vehicle 20, a robot 30 having a moving part 34 at the tip of an arm 32 on the upper surface of a body part 22 is arranged above the robot 30 with photographing means 40a and photographing means 40b (hereinafter also referred to as "photographing means 40"). ) are respectively provided. Each is electrically connected as shown. When the transport vehicle 20 moves an object with the arm 32, the photographing means 40 photographs an area including the arm 32 at predetermined intervals to acquire photographing information. When an obstacle is included in this photographing information, it is determined whether or not the arm 32 and the obstacle are within a predetermined approach range. Regulate movement. By doing so, it is possible to prevent the distance between the obstacle and the arm 32 from being included in the approach range, and reduce the possibility of contact between the obstacle and the arm 32 .

As shown in FIG. 1, the robot 30 is a six-axis arm robot having an arm 32 provided on the main body 22 of the carrier 20, and a moving section 34 is provided at the tip of the arm 32. As shown in FIG. Each of the six axes of the arm 32 and the moving portion 34 is provided with a red circular feature point as a feature point. In this way, by providing feature points on each axis and moving part 34, when extracting each axis and moving part 34 from imaging information obtained by imaging an area including the arm 32, compared to the case where no feature point is provided. can be easily extracted. Further, as shown in FIG. 3, the robot 30 is electrically connected to the control means 50, and when the moving part 34 moves the object, the movement of the arm 32 is controlled by the control means 50. The object is moved by the part 34 . By doing so, the robot 30 can load or unload the object on the transport vehicle 20 by pushing or pulling the object. Further, since the moving portion 34 is provided with a red circular characteristic point, when the image is captured by the image capturing means 40, the moving portion 34 can be easily extracted from the image capturing information. As a method for moving the object, the object may be moved by gripping or holding a part of the object, or by pressing or pulling one side of the object.

As shown in FIGS. 1 and 2, the photographing means 40 is a known photographing device provided above the carrier 20 and facing each other with the robot 30 interposed therebetween. The area containing the image is photographed and transmitted to the RAM 53, which will be described later, as photographing information. At this time, since the photographing means 40 are provided at positions facing each other with the robot 30 interposed therebetween, any of the photographing means 40 can photograph the area including the moving part 34 regardless of the state of the arm 32 . . In FIGS. 1 and 2, the photographing means 40a is provided on the upper right front side of the carrier 20, and the photographing means 40b is provided on the upper left rear side of the carrier 20. The positions are not limited, and for example, the photographing means 40a may be provided on the upper left front side and the photographing means 40b may be provided on the upper right rear side.

As shown in FIG. 3, the control means 50 is configured as a microprocessor with a CPU 51 at its center. A RAM 53 for temporarily storing reference information, photographing information, and the like, and an interface 54 (hereinafter referred to as "I/F 54") for transmitting and receiving various signals between the robot 30 and the photographing means 40, etc. They are electrically connected via a bus 55 . In addition to controlling the operations of the robot 30 and the photographing means 40, the control means 50 receives photographing information photographed by the photographing means 40 and determines whether or not an obstacle area corresponding to an obstacle is included. . By controlling the motion of the arm 32 based on this determination result, the possibility of contact between the arm 32 and an obstacle is reduced.

Next, a movement control processing routine executed by the control means 50 will be described as an example of a movement control processing method for preventing contact between the arm 32 and an obstacle. This movement control processing routine is executed when the arm 32 is moved, and is repeatedly executed while the arm 32 is moving. Here, FIG. 4 is a flowchart showing an example of the movement control processing routine.

A movement control processing routine is pre-stored in the ROM 52 and executed by the CPU 51 . When the movement control processing routine is executed by the CPU 51, the CPU 51 determines whether or not there is reference information in the RAM 53 (step S110). is transmitted, and the photographing information photographed by the photographing means 40 is temporarily stored in the RAM 53 as reference information (step S120). Since this reference information is stored in the RAM 53 while the robot 30 is running, step S120 is performed as a calibration operation when the robot 30 is started and the movement control processing routine is executed for the first time. will be executed only

Subsequently, after the CPU 51 executes step S120, or when it is determined that there is reference information in step S110, the CPU 51 transmits a photographing signal to the photographing means 40, and the photographing information photographed by the photographing means 40 is transmitted. It is temporarily stored in the RAM 53 (step S130), and the presence or absence of an obstacle is determined by determining whether or not obstacle information corresponding to an obstacle is included in the photographing information (step S140). Specifically, the reference information stored in the RAM 53 is compared with the photographing information, and it is determined whether or not the photographing information includes area information not included in the reference information. If the information is included in the shooting information, it is determined that the area corresponds to an obstacle, and that the obstacle is included.

If the CPU 51 determines in step S140 that there is no obstacle, this routine ends. In such a case, since there is no obstacle that hinders the movement of the arm 32, the arm 32 can be moved to the movement position for moving the object without obstruction.

On the other hand, when the CPU 51 determines in step S140 that there is an obstacle, the area corresponding to the obstacle in the imaging information is set as the obstacle area, and the area corresponding to the arm 32 in the imaging information is set as the arm area. A region corresponding to the moving portion 34 in the photographing information is extracted as a moving portion region (step S150). Specifically, image analysis processing of the imaging information is performed, and the area corresponding to the arm 32, the area corresponding to the moving part 34, and the area corresponding to the obstacle included in the imaging information are divided into the arm area, the moving part area, and the obstacle area, respectively. Each is extracted as an obstacle area.

Next, the positions of the moving part area and the obstacle area are compared to determine whether or not the moving part 34 is positioned above the obstacle (step S160). If it is determined that the arm 32 is not positioned, the movement of the arm 32 is restricted (step S190), and the routine ends. In such a case, the moving part 34 is positioned below the obstacle, and when the arm 32 is moved, there is a high possibility that the arm 32 will come into contact with the obstacle at some point. Therefore, by restricting the movement of the arm 32 in advance, the possibility of contact between the arm 32 and an obstacle can be reduced.

On the other hand, when the CPU 51 determines in step S160 that the moving part 34 is positioned above the obstacle, the distance between the arm 32 and the obstacle is calculated by calculating the distance between the arm area and the obstacle area. Calculate (step S170). Specifically, the distance from the obstacle area to the closest position of the arm area is calculated, and this distance is taken as the distance between the arm 32 and the obstacle. As a method of calculating the distance between the arm 32 and the obstacle, various methods of extracting spatial information from a still image and calculating the spatial information can be used. It may be calculated using a probability model such as

Subsequently, the CPU 51 determines whether or not the distance between the arm 32 and the obstacle calculated in step S160 is within the proximity range (step S180). finish. In such a case, there is no immediate contact between the arm 32 and the obstacle, so no control is required at this time. Here, the "proximity range" is a predetermined value, and when the distance between the arm and the obstacle is within the proximity range, the arm and the obstacle are approaching each other, This is a range indicating that there is a high possibility that the arm will come into contact with an obstacle as the arm moves. This range may be, for example, 0 mm or more and 100 mm or less, or 0 mm or more and 50 mm or less.

On the other hand, when the CPU 51 determines in step S180 that the distance between the arm 32 and the obstacle is within the proximity range, the movement of the arm 32 is restricted (step S190), and this routine ends. In such a case, since there is a high possibility that the arm 32 will come into contact with the obstacle by moving it, the possibility of contact between the arm 32 and the obstacle is reduced by restricting the movement of the arm 32. be able to.

According to the embodiment detailed above, the photographing means 40 photographs the area including the arm 32 to obtain photographing information, and in step S180, the arm area corresponding to the arm 32 and the obstacle area corresponding to the obstacle are captured. is within a predetermined proximity range, and if it is within the proximity range, the movement of the arm 32 is stopped. By doing so, it is possible to restrict the approach between the arm 32 and the obstacle, and reduce the possibility of the arm 32 colliding with the obstacle.

Further, before step S170, by comparing the reference information acquired in step S120 with the photographing information acquired in step S130, the presence or absence of an obstacle is determined in step S140. , there is no need to execute the processing after step S150. By doing so, it is possible to simplify the processing and improve the processing speed by determining in advance whether or not there is an obstacle.

Further, in step S160, the positional relationship between the moving part 34 and the obstacle is determined. , the movement of the arm 32 is stopped in step S190. If the arm 32 is moved in such a case, there is a high possibility that the arm 32 will collide with the obstacle. can be reduced.

Further, since the moving part 34 is provided with the feature points, it is easy to extract the feature points included in the reference information and the photographing information. In other words, it is possible to easily extract the grip portion region and the arm region included in the reference information and the imaging information, compared to the case where no feature point is provided.

It goes without saying that the present invention is not limited to the above-described embodiments, and can be implemented in various forms as long as they fall within the technical scope of the present invention.

For example, in the embodiment described above, the movement of the arm 32 is restricted in step S190, but the arm 32 may be moved in a direction other than the advancing direction, or the movement of the arm 32 may be stopped. and may control movement to avoid colliding with obstacles. In any case, by changing the movement of the arm 32, the same effect as the above-described embodiment can be obtained.

In the embodiment described above, it is determined whether or not there is reference information in step S110, but the reference information may be stored in the ROM 52 or the like in advance. This eliminates the need to execute steps S110 and S120.

In the above-described embodiment, in step S140, if an obstacle area corresponding to an obstacle is included in the photographing information, it is determined that there is an obstacle. It may be determined that there is an obstacle if the This allows the arm 32 to continue moving even if the imaging information includes a small obstacle that does not affect the movement of the arm 32 .

In the above-described embodiment, the feature point is assumed to be a red circle, but the feature point is not limited to this as long as it has a predetermined feature. Alternatively, various shapes such as a triangle, a square, and a cross may be used. Moreover, it may have a specific shape such as a concave portion or a convex portion. By providing a code that can be easily extracted during image processing in advance, the same effects as in the above-described embodiment can be obtained in either case.

In the embodiment described above, the value of the proximity range is determined in advance, but it may be determined based on the photographing interval of the photographing means 40 and the moving speed of the arm 32 . Specifically, a value obtained by multiplying the moving speed of the arm 32 by the photographing interval of the photographing means 40 may be used as the value of the proximity range. In this way, the arm 32 does not move more than the proximity range between the photographing means 40 next photographing the photographing information and the determination in this routine. If it is larger, there is no chance of arm 32 colliding with an obstacle.

In the above-described embodiment, the movement control processing routine is repeatedly executed, but when repeatedly executed, it may be executed after waiting for a predetermined period of time, such as 10 milliseconds or 1 second. . By doing so, the number of times of processing can be reduced and the load on the control means 50 can be reduced as compared with the case of continuous execution. Also, this standby time may be determined according to the moving speed of the arm 32, or may be determined based on the moving speed of the arm 32 and the value of the proximity range. For example, by setting the waiting time so that the product of the waiting time and the moving speed of the arm 32 is shorter than the value of the proximity range, the movement control processing routine is always executed while the arm 32 moves the distance of the proximity range. , the possibility of contact between the arm 32 and an obstacle can be reduced.

In the above-described embodiment, two photographing means 40 are provided, but four may be provided around the arm 32, or one may be provided. In either case, the possibility of collision between the arm 32 and the obstacle can be reduced in the same manner as in the above-described embodiments.

As shown in the above embodiments, it can be used in the field of robot control, particularly as contact prevention control means for a moving arm.

DESCRIPTION OF SYMBOLS 20... Carrier, 22... Main body part, 30... Robot, 32... Arm, 34... Moving part, 40... Photographing means, 40a... Photographing means, 40b... Photographing means, 50... Control means, 51... CPU, 52... ROM , 53...RAM, 54...interface, 55...bus.

Claims (8)

A robot equipped with an arm having a moving part for moving an object,
an imaging means for imaging an area including the arm and acquiring imaging information including an arm area corresponding to the arm;
In the photographing information, the distance between the obstacle area corresponding to the obstacle and the arm area is within a close proximity range obtained by multiplying the moving speed of the arm by the photographing interval of the photographing means. a control means for determining whether or not the arm is within the approach range, and regulating the movement of the arm when it is determined that the arm is within the approach range;
characterized by comprising
robot. The robot according to claim 1, wherein
Reference information obtained by photographing an area including the arm area in advance;
with
The control means determines whether or not the obstacle area is included in the imaging information by comparing the reference information and the imaging information, and determines that the obstacle area is included in the imaging information. In this case, it is determined whether or not the distance between the obstacle area and the arm area is within the approach range, and if it is determined that the distance is within the approach range, the movement of the arm is restricted. characterized by
robot. The control means regulates the movement of the arm when the moving part is positioned between an obstacle and a main body having an arm on the upper surface in the imaging information,
The robot according to claim 1 or 2. The moving unit is characterized by having a feature point that becomes a feature when photographed by the photographing means,
A robot according to any one of claims 1 to 3. The imaging means acquires the imaging information multiple times at imaging intervals determined based on the moving speed of the arm,
A robot according to any one of claims 1 to 4. A carrier equipped with the robot according to any one of claims 1 to 5,
A plurality of the photographing means are provided at a position for photographing the area including the robot from above,
transport vehicle. a photographing means for photographing an area including an arm and obtaining photographing information including the arm area corresponding to the arm; and in the photographing information, a distance between an obstacle area corresponding to an obstacle and the arm area is predetermined and control means for determining whether the object is within the approach range, and if it is determined that the object is within the approach range, the arm having a moving part for moving the object. A control method for controlling a robot comprising
a photographing step of acquiring the photographing information;
In the photographing information, whether or not the distance between the obstacle area corresponding to the obstacle and the arm area is within the proximity range obtained by multiplying the moving speed of the arm by the photographing interval of the photographing means. determining whether or not, and if it is determined that the arm is within the approach range, a restricting step of restricting the movement of the arm;
characterized by comprising
How to control the robot. A program for causing one or more computers to execute each step of the robot control method according to claim 7.

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