JP2017205819A - Robot, control device and robot system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a robot that can perform work together with a human while securing safety of the human who handles an object in a first region without prohibiting the robot from intruding in the first region.SOLUTION: A robot includes a movable part. In a first region where a robot operation region overlaps with a prescribed region, the movable part conducts operation based on a distance between the movable part and an object disposed in the first region.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a robot, a control device, and a robot system.

  Research and development are being carried out on technologies that control robot movements when robots and humans work in the same workspace.

  In this regard, a control method is known in which a robot entry prohibition area is provided in a cooperative operation area that is an area in which both a robot and a human can operate, and the robot is controlled so that the robot does not enter the robot entry prohibition area (Patent Literature). 1).

JP 2010-188515 A

  However, in such a control method, the setting of the robot entry prohibition area may be complicated, and it may be difficult for the robot and the human to safely perform work in the same work space. Moreover, in the said control method, there existed a possibility that a robot and a user may contact outside the robot approach prohibition area | region of a cooperative operation area | region.

In order to solve at least one of the above-described problems, an aspect of the present invention is a robot including a movable unit, and in the first region, which is a region where a motion region of the robot and a predetermined region overlap, A robot in which the movable unit performs an operation based on a distance between the movable unit and an object disposed in the first region.
With this configuration, the robot can perform an operation based on the distance between the movable unit and the object arranged in the first region in the first region, which is a region where the robot operation region and the predetermined region overlap. Do. As a result, the robot can work with the human being while ensuring the safety of the human who handles the object in the first area, without prohibiting the robot from entering the first area.

According to another aspect of the present invention, in the robot, in the first region, the distance between the movable part and the object is a first distance compared to the case where the distance between the movable part and the object is the first distance. When the distance is a second distance shorter than the first distance, a configuration in which the speed of the movable part is low may be used.
With this configuration, in the first region, the robot has the second distance in which the distance between the movable part and the object is shorter than the first distance compared to the case where the distance between the movable part and the object is the first distance. In this case, the moving part has a low speed. Accordingly, when the distance between the movable part and the object is the second distance shorter than the first distance in the first area, the robot handles the object in the first area by reducing the speed of the movable part. Can be secured.

According to another aspect of the present invention, in the robot, in the first region, the movable part and the object are compared with the case where the distance between the movable part and the object is the second distance. If the distance is a third distance shorter than the second distance, a configuration in which the speed of the movable part is low may be used.
With this configuration, in the first region, the robot has the third distance in which the distance between the movable part and the object is shorter than the second distance compared to the case where the distance between the movable part and the object is the second distance. In this case, the speed of the movable part is low. Thus, when the distance between the movable part and the human being is the third distance shorter than the second distance in the first area, the robot reduces the speed of the moving part to reduce the speed of the human handling the object in the first area. Safety can be ensured.

According to another aspect of the present invention, the robot includes a force detection unit that detects a force received from an object in contact with the movable unit, and the movable unit is moved when the object contacts the movable unit in the first region. When the distance between the movable part and the object is a fifth distance shorter than the fourth distance compared to the case where the distance between the part and the object is the fourth distance, the movable part contacts the movable part The structure which makes small the force which the said movable part applies to the said object may be used.
With this configuration, when the object comes into contact with the movable part in the first region, the robot has the distance between the movable part and the target compared to the case where the distance between the movable part and the target is the fourth distance. When the fifth distance is shorter than the four distances, the force applied by the movable part to the object in contact with the movable part is reduced. Accordingly, when the distance between the movable unit and the human is the fifth distance shorter than the fourth distance in the first region, the robot reduces the force applied by the movable unit to the object in contact with the movable unit. It is possible to ensure the safety of humans who handle objects in the area.

According to another aspect of the present invention, in the robot, when the object comes into contact with the movable part in the first region, the distance between the movable part and the object is the fifth distance. When the distance between the movable part and the object is a sixth distance shorter than the fifth distance, a configuration is used in which the force applied by the movable part to the object that contacts the movable part is reduced. May be.
With this configuration, when the object comes into contact with the movable part in the first region, the robot has a distance between the movable part and the target compared to the case where the distance between the movable part and the target is the fifth distance. When the sixth distance is shorter than 5 distances, the force applied by the movable part to the object in contact with the movable part is reduced. Accordingly, when the distance between the movable part and the human being is the sixth distance shorter than the fifth distance in the first region, the robot reduces the force applied by the movable part to the object in contact with the movable part. It is possible to ensure the safety of humans who handle objects in the area.

According to another aspect of the present invention, in the robot, when the object contacts the movable part in the first region, the distance between the movable part and the object in the first region is the fourth distance. When the distance between the movable part and the object is the fifth distance shorter than the fourth distance, the force detection part detects contact between the movable part and the object. A configuration with a small threshold value may be used.
With this configuration, when the object comes into contact with the movable part in the first region, the robot has the distance between the movable part and the target compared to the case where the distance between the movable part and the target is the fourth distance. When the fifth distance is shorter than four distances, the threshold value at which the force detection unit detects contact between the movable unit and the object is small. As a result, the robot reduces the threshold at which the force detection unit detects contact between the movable unit and the object when the distance between the movable unit and the human in the first region is a fifth distance shorter than the fourth distance. Thus, it is possible to ensure the safety of a person who handles an object in the first area.

According to another aspect of the present invention, the robot includes a detection unit that is provided on the movable unit and detects an object in a non-contact manner. When the detection unit detects the object, the movable unit is A configuration that performs at least one of decelerating a part or avoiding the object may be used.
With this configuration, when the detection unit detects an object, the robot performs at least one of deceleration of the movable unit and avoidance from the object. Thereby, the robot can suppress that a movable part contacts the person who handles a target object.

In another aspect of the present invention, in the robot, when the detection unit detects that the distance between the movable unit and the object is equal to or less than a predetermined distance, the movable unit decelerates the movable unit, or A configuration that performs at least one of avoidance from the object may be used.
With this configuration, when the detection unit detects that the distance between the movable unit and the object is equal to or less than the predetermined distance, the robot performs at least one of deceleration of the movable unit and avoidance from the object. Accordingly, when the detection unit detects that the distance between the movable unit and the object is equal to or less than the predetermined distance, the robot can suppress the movable unit from coming into contact with a person who handles the object.

According to another aspect of the present invention, in the robot, the movable portion includes a plurality of arms, and two adjacent arms among the plurality of arms among the plurality of trajectories along which the movable portion moves. The structure which operates the said movable part by the track | orbit selected based on the 1st angle may be used.
With this configuration, the robot operates the movable unit according to the trajectory selected based on the first angle formed by two adjacent arms among the plurality of trajectories in which the movable unit moves. Thereby, the robot can ensure the safety of a human who handles the object by the trajectory selected based on the first angle.

In another aspect of the present invention, in the robot, a configuration in which the first angle is not less than a predetermined first threshold value in a trajectory selected based on the first angle may be used.
With this configuration, the robot operates the movable unit according to a trajectory in which the first angle is equal to or greater than a predetermined first threshold among the plurality of trajectories along which the movable unit moves. As a result, the robot can ensure the safety of a human who handles the object by a trajectory having the first angle equal to or greater than the predetermined first threshold.

According to another aspect of the present invention, in the robot, in the trajectory selected based on the first angle, a second angle formed by two adjacent arms not including at least one of the two arms is: A configuration that is greater than or equal to a predetermined second threshold different from the first threshold may be used.
With this configuration, the robot operates the movable unit by a trajectory in which the first angle is equal to or greater than a predetermined first threshold value and the second angle is equal to or greater than a predetermined second threshold value. As a result, the robot can ensure the safety of a person who handles an object by a trajectory in which the first angle is equal to or greater than the predetermined first threshold and the second angle is equal to or greater than the predetermined second threshold.

Moreover, the other aspect of this invention is a control apparatus which controls the robot as described above.
With this configuration, the control device performs an operation based on the distance between the movable unit and the object arranged in the first region in the first region, which is a region where the motion region of the robot and the predetermined region overlap. To do. As a result, the control device can cause the robot to perform the work performed with the human being while ensuring the safety of the human who handles the object in the first area, without prohibiting the robot from entering the first area.

According to another aspect of the present invention, there is provided a robot system including the robot described above and a control device that controls the robot.
With this configuration, the robot system performs an operation based on the distance between the movable unit and the object arranged in the first region in the first region, which is a region where the motion region of the robot and a predetermined region overlap. To do. As a result, the robot system can cause the robot to perform the work performed with the human being while ensuring the safety of the human who handles the object in the first area, without prohibiting the robot from entering the first area.

As described above, the robot performs an operation based on the distance between the movable unit and the object arranged in the first region in the first region, which is a region where the motion region of the robot and the predetermined region overlap. . As a result, the robot can work with the human being while ensuring the safety of the human who handles the object in the first area, without prohibiting the robot from entering the first area.
In addition, the control device and the robot system perform an operation based on the distance between the movable unit and the object arranged in the first area in the first area, which is an area where the motion area of the robot overlaps the predetermined area. Let the moving part do it. As a result, the control device and the robot system allow the robot to perform the work performed with the human being while ensuring the safety of the human who handles the object in the first area, without prohibiting the robot from entering the first area. Can do.

It is a figure showing an example of composition of robot system 1 concerning a 1st embodiment. It is a figure for demonstrating the operation | movement which the robot 20 performs. 4 is a graph showing an example of a relationship between a speed V and a distance D of a movable part R included in a robot 20. 4 is a graph illustrating an example of a relationship between a contact detection threshold TH of a movable part R included in a robot 20 and a distance D. 2 is a diagram illustrating an example of a hardware configuration of a control device 30. FIG. 3 is a diagram illustrating an example of a functional configuration of a control device 30. FIG. 4 is a flowchart illustrating an example of a process flow in which the control device 30 controls the robot 20. It is a figure which shows an example of a structure of the robot system 1a which concerns on 2nd Embodiment. It is a figure which shows an example of the object detection range of the object detection part JS. It is a figure which shows an example of the object detection range of the object detection part JS. It is a figure which shows an example of the object detection range of the object detection part JS. It is a figure which shows an example of the object detection range of the object detection part JS. It is a figure which shows an example of a function structure of the control apparatus 30a. It is a flowchart which shows an example of the flow of the process which the control apparatus 30a controls the robot 20a. It is a figure which shows an example of a structure of the robot system 1b which concerns on 3rd Embodiment. It is a figure which shows an example of the angle of a bending joint. It is a figure which shows an example of the angle of a bending joint. It is a figure which shows an example of a function structure of the control apparatus 30b. It is a flowchart which shows an example of the flow of the process which the control apparatus 30b controls the robot 20b.

<First Embodiment>
Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

<Robot system configuration>
First, the configuration of the robot system 1 will be described.
FIG. 1 is a diagram illustrating an example of a configuration of a robot system 1 according to the present embodiment. The robot system 1 includes a robot 20 and a control device 30.

  The robot 20 is a single-arm robot including a movable part R and a support base B that supports the movable part R. The single-arm robot is a robot including one movable part (arm) such as the movable part R in this example. The robot 20 may be a multi-arm robot instead of the single-arm robot. The multi-arm robot is a robot having two or more movable parts (for example, two or more movable parts R). Note that a robot having two movable parts among the multi-arm robot is also referred to as a double-arm robot. That is, the robot 20 may be a double-arm robot having two movable parts, or a multi-arm robot having three or more movable parts (for example, three or more movable parts R). The robot 20 may be another robot such as a SCARA robot or a rectangular coordinate robot. The rectangular coordinate robot is, for example, a gantry robot.

The movable part R includes an end effector E, a manipulator M, and a force detector 21.
The end effector E is an end effector that grips an object. In this example, the end effector E includes a finger portion, and holds the object by holding the object with the finger portion interposed therebetween. The end effector E may be another end effector capable of lifting an object with a magnet, a jig, or the like, instead of the end effector provided with the finger portion.

  The manipulator M includes an arm A1 to an arm A6 that are six members among the members of the movable portion R, and a joint J1 to a joint J7 that are seven joints. The support base B and the arm A1 are connected by a joint J1. Arm A1 and arm A2 are connected by joint J2. Arm A2 and arm A3 are connected by joint J3. Arm A3 and arm A4 are connected by joint J4. Arm A4 and arm A5 are connected by joint J5. Arm A5 and arm A6 are connected by joint J6. Arm A6 and end effector E are connected by joint J7. Each of the joints J1 to J7 includes an actuator (not shown). That is, the movable part R including the manipulator M is a seven-axis vertical articulated movable part. The movable portion R may be configured to operate with a degree of freedom of 6 axes or less, or may be configured to operate with a degree of freedom of 8 axes or more.

  Each of the joint J2, the joint J4, and the joint J6 is a bending joint, and each of the joint J1, the joint J3, the joint J5, and the joint J7 is a torsional joint. As described above, the end effector E is connected (mounted) to the joint J7.

  Each of the seven actuators (provided at the joints) included in the manipulator M is communicably connected to the control device 30 via a cable. Thereby, the actuator operates the manipulator M based on the control signal acquired from the control device 30. Note that wired communication via a cable is performed according to standards such as Ethernet (registered trademark) and USB, for example. Moreover, the structure connected to the control apparatus 30 by the wireless communication performed by communication standards, such as Wi-Fi (trademark), may be sufficient as some or all of the seven actuators with which the manipulator M is provided.

  The force detection unit 21 is provided between the end effector E and the manipulator M. The force detection unit 21 is, for example, a force sensor. The force detection unit 21 detects a force or a moment (torque) applied to the end effector E or an object gripped by the end effector E. The force detection unit 21 outputs force detection information including a value indicating the magnitude of the detected force or moment as a force detection value to the control device 30 through communication.

  The force detection information is used for control based on the force detection information in the control of the movable part R by the control device 30. The control based on the force detection information is, for example, compliant motion control such as impedance control. Note that the force detection unit 21 may be an end effector E such as a torque sensor or another sensor that detects a value indicating the magnitude of force or moment applied to an object gripped by the end effector E. In addition, the force detection unit 21 may be configured to be provided in some or all of the joints J1 to J7 instead of the configuration provided between the end effector E and the manipulator M, or In addition to the structure provided in the meantime, the structure provided in part or all of the joints J1 to J7 may be used.

  The force detection unit 21 is communicably connected to the control device 30 via a cable. Wired communication via a cable is performed according to standards such as Ethernet (registered trademark) and USB, for example. The force detection unit 21 and the control device 30 may be configured to be connected by wireless communication performed according to a communication standard such as Wi-Fi (registered trademark).

  Hereinafter, unless it is necessary to distinguish each of the joints J1 to J7, or when the contents common to each of the joints J1 to J7 are described, they are collectively referred to as the joint J. In the following, unless there is a need to distinguish each of the arms A1 to A6, or when the contents common to each of the arms A1 to A6 are described, they are collectively referred to as the arm A.

  In this example, the control device 30 is a robot controller. The control device 30 generates a control signal based on an operation program input in advance. The control device 30 transmits the generated control signal to the robot 20 to cause the robot 20 to perform a predetermined operation.

  The control device 30 sets a control point T1, which is a TCP (Tool Center Point) that moves together with the end effector E, at a predetermined position of the end effector E. The predetermined position is, for example, a position on the rotation axis of the joint that rotates the end effector E, and is a position that is separated from the center of gravity of the end effector E by a predetermined distance toward the finger portion of the end effector E. The joint is a joint J7 included in the manipulator M. The predetermined position may be another position associated with the end effector E instead. The predetermined distance is, for example, a distance along the rotation axis from the end portion of the finger portion opposite to the manipulator M to the center of gravity. The predetermined distance may be another distance instead.

  The control point T1 is associated with control point position information that is information indicating the position of the control point T1 and control point attitude information that is information indicating the attitude of the control point T1. The control point T1 may be configured to be associated with other information in addition to these. The control device 30 designates (determines) each of the control point position information and the control point posture information. The control device 30 operates at least one of the joints J1 to J7 of the movable part R, matches the position of the control point T1 with the position indicated by the designated control point position information, and designates the designated control point posture information. The posture of the control point T1 is matched with the posture indicated by. That is, the control device 30 operates the robot 20 by designating control point position information and control point posture information.

  In this example, the position of the control point T1 is represented by the position in the robot coordinate system RC of the origin of the control point coordinate system TC. Further, the posture of the control point T1 is represented by the direction in the robot coordinate system RC of each coordinate axis of the control point coordinate system TC. The control point coordinate system TC is a three-dimensional local coordinate system associated with the control point T1 so as to move with the control point T1. In this example, the position and posture of the end effector E are represented by the position and posture of the control point T1.

  The control device 30 sets the control point T1 based on control point setting information previously input from the user. The control point setting information is, for example, information indicating a relative position and posture between the position and posture of the center of gravity of the end effector E and the position and posture of the control point T1. Instead of this, the control point setting information may be information indicating a relative position and posture between any position and posture associated with the end effector E and the position and posture of the control point T1, It may be information indicating a relative position and posture between any position and posture associated with the manipulator M and the position and posture of the control point T1, and may include any position and posture associated with other parts of the robot 20. It may be information indicating a relative position and posture between the posture and the position and posture of the control point T.

  The control device 30 generates a route for moving the control point T1. Based on the generated route, the control device 30 designates control point position information and control point posture information every time, and moves the control point T1 along the route. At this time, the control device 30 generates a control signal including the designated control point position information and control point attitude information. The control signal includes other signals such as a signal for moving the finger of the end effector E. And the control apparatus 30 transmits the produced | generated control signal to the robot 20, and makes the robot 20 perform a predetermined | prescribed operation | work.

  In this example, the control device 30 is installed outside the robot 20. The control device 30 may be configured to be built in the robot 20 instead of the configuration installed outside the robot 20.

<Predetermined work performed by the robot>
Hereinafter, predetermined work performed by the robot 20 will be described.
In this example, the robot 20 grips the object O placed at the predetermined position Pa and carries it to the predetermined position Pb (not shown) as the predetermined work. The object O is placed at a predetermined position Pa on the upper surface of the work table TB as shown in FIG. The robot 20 moves the movable part R, and grips the object O placed at a predetermined position Pa on the upper surface of the work table TB by the end effector E, and the gripped object O is not shown in the figure. It is carried (placed) to the position Pb.

<Operations performed by the robot in a predetermined operation>
Hereinafter, with reference to FIGS. 2 to 4, an operation performed by the robot 20 in a predetermined operation will be described. FIG. 2 is a diagram for explaining an operation performed by the robot 20. FIG. 2 shows a worker operation area 100 and a robot operation area 102. The worker operation area 100 is a predetermined area where the worker can operate. The robot operation area 102 is a predetermined area in which the robot 20 can operate. The object O is placed at a predetermined position Pa in the first area, which is an area where the worker motion area 100 and the robot motion area 102 overlap. In this example, the worker places the object O at a predetermined position Pa, and the robot 20 grips the object O placed at the predetermined position Pa and carries it to a predetermined position Pb (not shown). That is, in the first area, the worker and the robot 20 work in cooperation.

The movable part R of the robot 20 performs an operation based on the distance D between the movable part R and the object O arranged at a predetermined position Pa in the first region. Accordingly, the user can cause the robot 20 to perform work together with the human being while ensuring the safety of the human who handles the object O in the first area, without prohibiting the robot 20 from entering the first area. The distance D is, for example, the distance between the position Pa of the object O and the position of the control point T1 in the robot coordinate system RC.
In FIG. 2, a range 108 in which the distance D between the position Pa of the object O and the position of the control point T1 is the first distance d1, a range 106 in which the distance D is the second distance d2, and the distance A range 104 where D is the third distance d3 is shown. In this example, the first distance d1 is the largest, the second distance d2 is medium, and the third distance d3 is the smallest.

  FIG. 3 is a graph showing an example of the relationship between the speed V and the distance D of the movable part R included in the robot 20. In the graph shown in FIG. 3, the horizontal axis represents the distance D, and the vertical axis represents the speed. The speed V is represented by the speed of the control point T1 in this example. The speed V may be the speed of another part of the movable part R. In the example shown in FIG. 3, when the distance D between the movable part R and the object O is the first distance d1, the speed V of the movable part R is the speed v1. In this example, when the distance D between the movable part R and the object O is the second distance d2, the speed V of the movable part R is the speed v2. In this example, when the distance D between the movable part R and the object O is the third distance d3, the speed V of the movable part R is the speed v3.

  As shown in FIG. 3, when the distance D between the movable part R and the object O is the second distance d2 shorter than the first distance d1, the speed v2 of the movable part R is the movable part R and the object O. The distance D is lower than the speed v1 when the distance D is the first distance d1. Further, when the distance D between the movable part R and the object O is the third distance d3 shorter than the second distance d2, the speed v3 of the movable part R is such that the distance D between the movable part R and the object O is the first. The speed is lower than the speed v2 when the distance is two distances d2. That is, the speed of the movable part R becomes lower as the distance D is shorter. Here, the shorter the distance D, the closer the movable part R is to the object O. The situation where the movable part R is located near the object O can be said to be a situation where there is a high possibility that the worker placing the object O at the position Pa and the movable part R will come into contact with each other. From this, the shorter the distance D, the lower the speed V of the movable part R, that is, the higher the possibility that the movable part R approaches the worker, the slower the speed V of the movable part R is. It can suppress that the part R contacts.

  FIG. 4 is a graph showing an example of the relationship between the contact detection threshold TH of the movable part R and the distance D provided in the robot 20. In the graph shown in FIG. 4, the horizontal axis represents the distance D, and the vertical axis represents the contact detection threshold TH. The contact detection threshold TH is a threshold for the force detection unit 21 to determine whether another object has contacted the movable unit R based on force detection information including the force detection value detected by the force detection unit 21. It is. For example, when the force detection unit 21 determines that the force detection value is greater than or equal to the contact detection threshold TH based on the force detection information, the force detection unit 21 detects that another object has contacted the movable unit R. In addition, the process which determines whether other objects contacted the movable part R based on force detection information instead of the structure which the force detection part 21 performs may be the structure which the control apparatus 30 performs.

  When the force detection unit 21 detects that another object has contacted the movable unit R, the robot 20 performs a predetermined operation. The predetermined operation is, for example, an operation of stopping the operation of the movable part R or returning the position of the movable part R by a predetermined amount. The predetermined operation eliminates the force applied to the object when the movable part R contacts another object.

  The contact detection threshold TH is the threshold th2 when the distance D between the movable part R and the object O is the second distance d2 shorter than the first distance d1, and the distance D between the movable part R and the object O is the first. It is smaller than the threshold th1 in the case of 1 distance d1. When the distance D between the movable part R and the object O is the third distance d3 that is shorter than the second distance d2, the contact detection threshold value TH is the distance D between the movable part R and the object O being the second distance d2. It is smaller than the threshold value th2 in some cases. That is, the contact detection threshold TH becomes smaller as the distance D is shorter. Here, the smaller the contact detection threshold TH, the smaller the force applied to the object when the movable part R contacts the object. Therefore, in the robot 20, when an object comes into contact with the movable part R, the distance between the movable part R and the object O compared to the case where the distance D between the movable part R and the object O is the first distance d <b> 1. When D is the second distance d2 shorter than the first distance d1, the force applied to the object in contact with the movable part R is small. In the robot 20, the distance D between the movable part R and the object O is shorter than the second distance d2 as compared with the case where the distance D between the movable part R and the object O is the second distance d2. In the case of 3 distances d3, the force applied to the object in contact with the movable part R is small.

Here, in this example, compared to the case where the distance between the movable part R and the object O is the fourth distance, the distance between the movable part R and the object O is a fifth distance shorter than the fourth distance. In a case where the force applied by the movable part R to the object O in contact with the movable part R is reduced, the first distance d1 is used as the fourth distance, and the second distance d2 is used as the fifth distance. However, as another configuration example, other values may be used as the fourth distance and the fifth distance.
Similarly, in this example, compared with the case where the distance between the movable part R and the object O is the fifth distance, the distance between the movable part R and the object O is a sixth distance shorter than the fifth distance. In some cases, in the configuration in which the force applied by the movable part R to the object O in contact with the movable part R is reduced, the second distance d2 is used as the fifth distance, and the third distance d3 is used as the sixth distance. However, as another configuration example, other values may be used as the fifth distance and the sixth distance.

  The shorter the distance D, the closer the movable part R is to the object O. It can be said that the situation where the movable part R exists closer to the object O is a situation where the operator who places the object O at the position Pa and the movable part R are more likely to contact each other. From this, the contact detection threshold value TH becomes smaller as the distance D is shorter, so that the detection sensitivity that an object contacts the movable part R becomes more sensitive as the possibility that the movable part R approaches the worker is higher. it can. Thereby, even if the movable part R contacts the worker, the shorter the distance D, the smaller the force is detected, and the movable part R is stopped by stopping the operation of the movable part R, for example. The force applied to can be reduced.

<Outline of processing performed by control device>
Hereinafter, an outline of processing performed by the control device 30 will be described.
The control device 30 calculates a distance D between the position Pa of the object O and the position of the control point T1 in the robot coordinate system RC. The position Pa of the object O in the robot coordinate system RC is input in advance to the control device 30 by the user. The control device 30 changes the speed V of the movable part R according to the distance D between the position Pa of the object O and the position of the control point T1 in the robot coordinate system RC. The control device 30 decreases the speed V of the movable part R as the distance D is shorter. The control device 30 changes the contact detection threshold TH according to the distance D between the position Pa of the object O and the position of the control point T1 in the robot coordinate system RC. The control device 30 decreases the contact detection threshold TH as the distance D is shorter.

<Hardware configuration of control device>
Hereinafter, the hardware configuration of the control device 30 will be described with reference to FIG. FIG. 5 is a diagram illustrating an example of a hardware configuration of the control device 30.
The control device 30 includes, for example, a CPU (Central Processing Unit) 31, a storage unit 32, an input reception unit 33, a communication unit 34, and a display unit 35. Further, the control device 30 communicates with the robot 20 via the communication unit 34. These components are connected to each other via a bus Bus so that they can communicate with each other.

The CPU 31 executes various programs stored in the storage unit 32.
The storage unit 32 includes, for example, a hard disk drive (HDD), a solid state drive (SSD), an electrically erasable programmable read-only memory (EEPROM), a read-only memory (ROM), and a random access memory (RAM). Note that the storage unit 32 may be an external storage device connected by a digital input / output port such as a USB instead of the one built in the control device 30. The storage unit 32 stores various information, images, and programs processed by the control device 30.

The input receiving unit 33 is, for example, a touch panel configured integrally with the display unit 35. The input receiving unit 33 may be a keyboard, a mouse, a touch pad, or other input device.
The communication unit 34 includes, for example, a digital input / output port such as USB, an Ethernet (registered trademark) port, and the like.
The display unit 35 is, for example, a liquid crystal display panel or an organic EL (ElectroLuminescence) display panel.

<Functional configuration of control device>
Hereinafter, the functional configuration of the control device 30 will be described with reference to FIG. FIG. 6 is a diagram illustrating an example of a functional configuration of the control device 30. The control device 30 includes a control unit 40.

  The control unit 40 controls the entire control device 30. The control unit 40 includes a robot control unit 41, a setting unit 42, and a contact detection unit 43. These functional units included in the control unit 40 are realized, for example, when the CPU 31 executes various programs stored in the storage unit 32. Further, some or all of the functional units may be hardware functional units such as LSI (Large Scale Integration) and ASIC (Application Specific Integrated Circuit).

  The robot control unit 41 causes the robot 20 to perform a predetermined operation. The setting unit 42 sets values used for controlling the robot 20. Examples of values used for controlling the robot 20 include the speed V of the movable part R of the robot 20 and the contact detection threshold value TH. The contact detection unit 43 detects that an object has contacted the movable unit R of the robot 20 using the force detection information output from the force detection unit 21 of the robot 20 and the contact detection threshold value TH.

<Processing where the control device controls the robot>
Hereinafter, a process in which the control device 30 controls the robot 20 will be described with reference to FIG. FIG. 7 is a flowchart illustrating an example of a process flow in which the control device 30 controls the robot 20.

  The setting unit 42 sets the target position Pt (Step S11). In this example, the target position Pt is a position in the robot coordinate system RC of the control point T1 at which the end effector E can grip the object O. The setting unit 42 obtains the target position Pt based on the position Pa of the object O in the robot coordinate system RC. The position Pa of the object O in the robot coordinate system RC is input in advance to the control device 30 by the user.

  The robot control unit 41 detects the distance D between the movable unit R and the object O (step S12). In this example, the distance D between the movable part R and the object O is the distance between the position Pa of the object O and the position of the control point T1 in the robot coordinate system RC.

  The setting unit 42 sets the contact detection threshold TH corresponding to the distance D between the movable part R and the object O and the speed V of the movable part R (step S13).

  For example, the setting unit 42 has distance-speed correspondence data representing the relationship between the distance D and the speed V shown in FIG. The setting unit 42 sets the speed V corresponding to the distance D detected by the robot control unit 41 based on the distance-speed correspondence data. For example, the setting unit 42 sets a speed (speed corresponding to the distance D) higher than the speed v1 as the speed V when the distance D exceeds the first distance d1, and the distance D is equal to or less than the first distance d1. If the distance D2 exceeds the distance d2, a speed exceeding the speed v1 and a speed exceeding the speed v2 (a speed corresponding to the distance D) is set. A speed exceeding v3 (speed corresponding to the distance D) is set, and when the distance D is equal to or smaller than the third distance d3, a speed equal to or lower than the speed v3 (speed corresponding to the distance D) is set.

  For example, the setting unit 42 has distance-threshold correspondence data representing the relationship between the distance D and the contact detection threshold TH shown in FIG. The setting unit 42 sets a contact detection threshold TH corresponding to the distance D detected by the robot control unit 41 based on the distance-threshold correspondence data. For example, the setting unit 42 sets a threshold (threshold corresponding to the distance D) that exceeds the threshold th1 when the distance D exceeds the first distance d1 as the contact detection threshold TH, and the distance D is equal to or less than the first distance d1. When the second distance d2 is exceeded, a threshold (threshold corresponding to the distance D) is set that is less than the threshold th1 and greater than the threshold th2, and when the distance D is less than the second distance d2 and greater than the third distance d3, A threshold value (threshold value corresponding to the distance D) exceeding the threshold value th3 is set, and when the distance D is equal to or less than the third distance d3, a threshold value (threshold value corresponding to the distance D) equal to or less than the threshold value th3 is set.

  The robot control unit 41 moves the movable unit R at the speed V set by the setting unit 42 so that the position of the control point T1 coincides with the target position Pt (step S14).

The contact detection unit 43 uses the force detection information output from the force detection unit 21 and the contact detection threshold TH to detect that an object has contacted the movable unit R (step S15). The contact detection unit 43 compares the value indicating the magnitude of the force or moment included in the force detection information output from the force detection unit 21 with the contact detection threshold TH set by the setting unit 42. As a result of this comparison, when the value indicating the magnitude of force or moment is equal to or greater than the contact detection threshold TH, the contact detection unit 43 detects that an object has contacted the movable unit R, and otherwise, The contact detection unit 43 does not detect that an object has contacted the movable unit R.
Here, in the process of determining the presence or absence of contact based on the value indicating the magnitude of the force or moment included in the force detection information, for example, any one of force and moment may be used, or both May be used. As the contact detection threshold value TH, for example, different values may be used for each of force and moment, or the same value may be used.

  When the contact detection unit 43 detects that an object has contacted the movable part R (step S15, YES), the robot control unit 41 causes the robot 20 to perform a predetermined operation (step S16). The predetermined operation is, for example, stopping the operation of the movable part R. Alternatively, the predetermined operation is, for example, an operation for returning the position of the movable portion R by a predetermined amount.

  The robot control unit 41 determines whether or not the position of the control point T1 has reached (matched) the target position Pt when the contact detection unit 43 does not detect that the object has contacted the movable unit R (step S15, NO). Is determined (step S17). If the result of this determination is that the position of the control point T1 has reached the target position Pt, the processing in FIG. 7 ends. On the other hand, if the position of the control point T1 has not reached the target position Pt, the process proceeds to step S12.

  As described above, in the first embodiment, the control device 30 has the object O arranged at the predetermined position Pa in the movable portion R and the region where the worker motion region 100 and the robot motion region 102 overlap. The robot 20 is controlled so that the movable part R performs an operation based on the distance D between the robot 20 and the robot. Thereby, it is not necessary to set the robot entry prohibition region in the region where the robot operation region and the predetermined region overlap.

Second Embodiment
Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

<Robot system configuration>
First, the configuration of the robot system 1a will be described.
FIG. 8 is a diagram showing an example of the configuration of the robot system 1a according to the present embodiment. 8, parts corresponding to those in FIG. 1 are denoted by the same reference numerals, and description thereof is omitted. The robot system 1a includes a robot 20a and a control device 30a. The robot 20a includes a support base B and a movable part R similar to those shown in FIG. 1, and further, an object detection part JS1 to an object detection part JS7 are provided at each of the joints J1 to J7 of the manipulator M of the movable part R. Is provided.
Below, unless it is necessary to distinguish each of the object detection unit JS1 to the object detection unit JS7, or when explaining the contents common to each of the object detection unit JS1 to the object detection unit JS7, the object detection unit This will be described as JS. In this example, the manipulator M includes object detection units JS1 to JS7 in each of the seven joints J1 to J7, but at least one of the seven joints J1 to J7. The object detection unit JSN may be provided at the joint JN (where N is an integer from 1 to 7).

  The object detection unit JS detects an object without contact. For example, the object detection unit JS is a sensor that detects an object in a non-contact manner using electromagnetic waves or sound waves such as laser light, infrared light, or ultrasonic waves. Alternatively, the object detection unit JS is an image processing device that includes an imaging device and detects an object in a non-contact manner using an image captured by the imaging device. The object detection unit JS outputs object detection information, which is information related to the detection result of the object, to the control device 30a by communication.

<Object detection range of the object detection unit>
Hereinafter, an object detection range that is a range in which the object detection unit JS detects an object in a non-contact manner will be described with reference to FIGS. 9 to 12. 9-12 is a figure which shows an example of the object detection range of the object detection part JS. In the example of FIG. 9, the object detection unit JS7 of the joint J7 has a circular object detection range 201 with the axis of the joint J7 as the central axis. In this example, the circle is a circle in a plane perpendicular to the axis of the joint J7. The object detection unit JS7 detects an object existing in the object detection range 201 in a non-contact manner.
In the example of FIG. 10, the object detection unit JS7 of the joint J7 has a conical object detection range 202 with the axis of the joint J7 as the central axis. In this example, the conical shape is a conical shape in which the circular shape increases from the joint J7 toward the end effector E along the axis of the joint J7. The object detection unit JS7 detects an object existing in the object detection range 202 in a non-contact manner.
The same applies to the object detection unit JS1 of the joint J1, the object detection unit JS3 of the joint J3, and the object detection unit JS5 of the joint J5.

In the example of FIG. 11, the object detection unit JSx of the joint Jx (in this example, x is any one of 2, 4, and 6) is a circular object detection range centering on the axis of the arm (link) in the joint Jx. 211. In this example, the arm is an arm on the side opposite to the end effector E with respect to the joint Jx. Further, in this example, the position of the center of the circle is slightly away from the joint Jx in the arm. Further, in this example, the circle is a circle in a plane perpendicular to the axis of the arm. The object detection unit JSx detects an object existing in the object detection range 211 in a non-contact manner.
In the example of FIG. 12, the object detection unit JSx of the joint Jx has a conical object detection range 212 with the axis of the arm (link) in the joint Jx as the central axis. In this example, the arm is an arm on the side opposite to the end effector E with respect to the joint Jx. Further, in this example, the position of the center of the conical shape is slightly away from the joint Jx in the arm. In this example, the conical shape is a conical shape in which a circular shape increases from the object detection unit JSx toward the end effector E along the axis of the arm. The object detection unit JSx detects an object existing in the object detection range 212 in a non-contact manner.

  Note that the object detection unit JS may change the shape of the object detection range. For example, as the shape of the object detection range, a circle and a cone may be alternately changed at a fixed time interval. Further, the control device 30a may control the object detection unit JS so as to change the shape and size of the object detection range of the object detection unit JS according to the posture of the robot 20a and the work content. As described above, the control device 30a may change the object detection range of the object detection unit JS according to one or more of the posture, work content, timing, and the like of the robot 20a.

<Operations performed by the robot>
Hereinafter, operations performed by the robot 20a will be described. The robot 20a performs a predetermined work. The predetermined operation is the same as that in the first embodiment described above. As shown in FIG. 2, the worker places the object O at a predetermined position Pa, and the robot 20a grips the object O placed at the predetermined position Pa and carries it to another predetermined position Pb. That is, in a region where the worker motion region 100 and the robot motion region 102 overlap with each other, the worker and the robot 20a work in cooperation.

  In the robot 20a, an object detection unit JS that detects an object in a non-contact manner is provided in the movable unit R. When the object detection unit JS detects an object, the movable unit R performs at least one of deceleration of the movable unit R and avoidance from the object. Thereby, it can be easy to avoid that an operator contacts the movable part R.

  Furthermore, when the object detection unit JS detects that the distance between the movable unit R and the object is equal to or less than a predetermined distance, the movable unit R performs at least one of deceleration of the movable unit R or avoidance from the object. You may go. Thereby, it can be easy to avoid that an operator contacts the movable part R. Further, when the distance between the movable part R and the object exceeds the predetermined distance, the predetermined work of the robot 20a can be advanced as planned.

<Functional configuration of control device>
Hereinafter, the functional configuration of the control device 30a will be described with reference to FIG. FIG. 13 is a diagram illustrating an example of a functional configuration of the control device 30a. The control device 30a includes a control unit 40a. Note that the hardware configuration of the control device 30a is the same as that shown in FIG. 5, and will be described using the same reference numerals.

  The control unit 40a controls the entire control device 30a. The control unit 40a includes a robot control unit 41a, a setting unit 42a, and an object detection processing unit 44. These functional units included in the control unit 40a are realized by the CPU 31 executing various programs stored in the storage unit 32, for example. Also, some or all of the functional units may be hardware functional units such as LSI and ASIC.

  The robot control unit 41a causes the robot 20a to perform a predetermined operation. The predetermined operation is the same as that in the first embodiment described above. The setting unit 42a sets values used for controlling the robot 20a. The object detection processing unit 44 determines whether the object detected by the object detection unit JS is the target object O or the robot 20a.

<Processing where the control device controls the robot>
Hereinafter, a process in which the control device 30a controls the robot 20a will be described with reference to FIG. FIG. 14 is a flowchart illustrating an example of a process flow in which the control device 30a controls the robot 20a.

  The object detection processing unit 44 performs object detection processing (step S31). In the object detection process, the object detection processing unit 44 acquires object detection information output from the object detection unit JS of the robot 20a.

  The object detection processing unit 44 determines whether or not the object detection unit JS has detected an object based on the acquired object detection information (step S32). For example, the object detection information is information including a value indicating that the object detection unit JS has detected an object. When the acquired object detection information includes the value, the object detection processing unit 44 determines that the object detection unit JS has detected the object. Otherwise, the object detection unit JS has detected the object. Do not judge. If the object detection processing unit 44 determines that the object detection unit JS has detected an object, the process proceeds to step S33, and if not, the process in step S31 is repeated.

  The object detection processing unit 44 determines whether or not the object detected by the object detection unit JS is the target object O or the robot 20a (step S33). The object detection processing unit 44 detects whether the object detected by the object detection unit JS is the target object O or the robot 20a based on the acquired object detection information, the information about the target object O, and the information about the movable part R of the robot 20a. Judge whether there is. For example, the object detection information includes information such as the position, shape, direction, and distance of the object detected by the object detection unit JS.

  For example, the object detection processing unit 44 compares the shape of the object indicated by the object detection information with the shape of the target object O indicated by the information on the target object O, and the object detection unit JS detects based on the comparison result. It is determined whether or not the obtained object is the object O. Alternatively, the object detection processing unit 44 compares, for example, the direction of the object indicated by the object detection information with the direction of the object O indicated by the information on the object O, and based on the result of this comparison, the object detection unit JS. It is determined whether or not the detected object is the object O.

The object detection processing unit 44 determines whether the object detected by the object detection unit JS is the robot 20a based on the posture indicated by the information on the movable part R of the robot 20a and the direction of the object indicated by the object detection information. To do.
Here, as the direction of the object or the direction of the object O, for example, a posture may be used.
Moreover, the method of determining whether the object detected by the object detection unit JS is the target object O or the robot 20a may be arbitrary. In this example, it is determined whether or not the object detected by the object detection unit JS is the target object O, and whether or not the object detected by the object detection unit JS is the robot 20a. However, as another example, any one of them may be performed.

  If the object detection processing unit 44 determines that the object detected by the object detection unit JS is the target object O or the robot 20a, the process proceeds to step S31. If not, the process proceeds to step S34. .

  Here, in addition to the above determination, the object detection processing unit 44 may further determine whether the distance of the object indicated by the object detection information is equal to or less than a predetermined distance. In this case, when the object detection processing unit 44 determines that the object detected by the object detection unit JS is the object O or the robot 20a, the process proceeds to step S31. On the other hand, when the object detection processing unit 44 determines that the object detected by the object detection unit JS is neither the object O nor the robot 20a, and the object distance indicated by the object detection information is equal to or less than a predetermined distance. The process proceeds to step S34, and if not, the process proceeds to step S31.

  In step S34, the robot control unit 41 causes the robot 20a to perform a predetermined operation. The predetermined operation is, for example, at least one operation of decelerating the movable part R or avoiding the object detected by the object detection unit JS.

  Note that after step S34, the object detection processing unit 44 may determine whether or not the object detection unit JS stops detecting the object. In this configuration, when the object detection processing unit 44 determines that the object detection unit JS no longer detects an object after step S34, the robot control unit 41 cancels the predetermined operation performed in step S34. The control for causing the robot 20a to perform a predetermined work is resumed.

  As described above, in the second embodiment, the robot 20a is provided with the object detection unit JS that detects an object in a non-contact manner in the movable unit R. When the object detection unit JS detects an object, the control device 30a controls the robot 20a so that the movable unit R performs at least one of deceleration of the movable unit R or avoidance from the object. Thereby, it can be easy to avoid that an operator contacts the movable part R.

  In addition, you may implement combining 1st Embodiment mentioned above and 2nd Embodiment. When the first embodiment and the second embodiment are implemented in combination, the robot 20a shown in FIG. 8 further includes a force detection unit 21 shown in FIG. Further, the control device 30a shown in FIG. 13 further includes a contact detection unit 43 shown in FIG. In the control device 30a, the robot control unit 41a further has the function of the robot control unit 41 shown in FIG. 6, and the setting unit 42a further has the function of the setting unit 42 shown in FIG.

<Third Embodiment>
Hereinafter, a third embodiment of the present invention will be described with reference to the drawings.

<Robot system configuration>
First, the configuration of the robot system 1b will be described.
FIG. 15 is a diagram illustrating an example of the configuration of the robot system 1b according to the present embodiment. In FIG. 15, parts corresponding to those in FIG. The robot system 1b includes a robot 20b and a control device 30b. The robot 20b performs a predetermined operation. The predetermined operation is the same as that in the first embodiment described above. As shown in FIG. 2, the worker places the object O at a predetermined position Pa, and the robot 20b grips the object O placed at the predetermined position Pa and carries it to another predetermined position Pb. That is, in a region where the worker motion region 100 and the robot motion region 102 overlap each other, the worker and the robot 20b work together.

  The robot 20b includes a support base B and a movable part R similar to those shown in FIG. In the robot 20b, the joint J2, the joint J4, and the joint J6 of the manipulator M of the movable part R are bending joints. A bending joint is a joint that connects adjacent arms. The joint J2 is a bending joint that connects the arm A1 and the arm A2. The joint J4 is a bending joint that connects the arm A3 and the arm A4. The joint J6 is a bending joint that connects the arm A5 and the arm A6.

<Bend joint angle>
Hereinafter, the angle of the bending joint will be described with reference to FIGS. 16 and 17. 16 and 17 are diagrams illustrating an example of the angle of the bending joint. The joint Jx (in this example, x is any one of 2, 4, and 6) is a bending joint that connects the arm Ax and the arm Ay. In this example, y is “x−1”. An angle θ formed by two adjacent arms Ax and the arm Ay to which the joint Jx is connected changes according to the posture of the movable part R.

  The angle θ2 formed by the two adjacent arms Ax and the arm Ay shown in FIG. 17 is larger than the angle θ1 formed by the two adjacent arms Ax and the arm Ay shown in FIG. The greater the angle θ formed between the two adjacent arms Ax and Ay, the lower the possibility that an operator's arm or finger will be sandwiched between the two arms Ax and Ay. Further, as the angle θ between the two adjacent arms Ax and Ay increases, the force applied to the object sandwiched between the two arms Ax and Ay decreases. Therefore, the worker is safer when the angle θ formed by the two adjacent arms Ax and Ay is larger.

<Operations performed by the robot>
Hereinafter, the operation performed by the robot 20b will be described.
In the robot 20b, the movable part R has a plurality of arms A1 to A6. In the present embodiment, among the plurality of trajectories in which the movable part R moves, the trajectory Rt selected based on the first angle θ_a formed by the two adjacent arms Ax and Ay among the plurality of arms A1 to A6. The movable part R operates. Thereby, the movable part R can be operated by the track Rt selected in consideration of the safety of the worker based on the first angle θ_a formed by the two adjacent arms Ax and Ay.

  Here, the first angle θ_a may be greater than or equal to a predetermined first threshold th_a in the trajectory in which the movable part R operates. Thereby, the first angle θ_a formed by the two adjacent arms Ax and Ay is set to be equal to or larger than the first threshold th_a, and the safety of the worker can be achieved.

Further, in the trajectory in which the movable part R operates, the second threshold θ_b formed by the two adjacent arms not including at least one of the two adjacent arms Ax and Ay is different from the first threshold th_a. It may be greater than th_b. Accordingly, the first angle θ_a and the second angle θ_b in two adjacent bending joints can be set to be equal to or greater than the first threshold th_a and equal to or greater than the second threshold th_b, respectively. Also, by changing the range of possible values of the first angle θ_a and the second angle θ_b at these bending joints, the range of selection of the trajectory on which the movable portion R operates increases, so that the movable portion R can be made more efficient. Can be operated in orbit.
Here, the first threshold th_a and the second threshold th_b may each be an arbitrary value larger than 0.

<Functional configuration of control device>
Hereinafter, the functional configuration of the control device 30b will be described with reference to FIG. FIG. 18 is a diagram illustrating an example of a functional configuration of the control device 30b. The control device 30b includes a control unit 40b. Note that the hardware configuration of the control device 30b is the same as the configuration shown in FIG.

  The control unit 40b controls the entire control device 30b. The control unit 40b includes a robot control unit 41b, a setting unit 42b, a trajectory generation unit 45, an evaluation unit 46, and a trajectory selection unit 47. These functional units included in the control unit 40b are realized by the CPU 31 executing various programs stored in the storage unit 32, for example. Also, some or all of the functional units may be hardware functional units such as LSI and ASIC.

  The robot control unit 41b causes the robot 20b to perform a predetermined operation. The predetermined operation is the same as that in the first embodiment described above. The setting unit 42b sets values used for controlling the robot 20b. The trajectory generation unit 45 generates a plurality of trajectory candidates. The trajectory candidate is a trajectory candidate along which the movable part R moves. In this example, the trajectory is represented by a sequence of positions in the robot coordinate system RC of a plurality of passing points through which the control point T1 passes when the movable part R moves.

  One trajectory candidate is associated with passing point position information indicating the position of the passing point and passing point posture information indicating the attitude of the movable part R at the passing point for each passing point of the trajectory candidate. Yes. In this example, the passing point posture information is information including a first angle θ_a formed by two adjacent arms Ax and Ay among the plurality of arms A1 to A6. That is, in this example, the passing point posture information includes an angle formed by the arm A1 and the arm A2, an angle formed by the arm A2 and the arm A3, an angle formed by the arm A4 and the arm A5, and an angle formed by the arm A5 and the arm A6. And information including.

  The evaluation unit 46 evaluates a plurality of trajectory candidates generated by the trajectory generation unit 45. In this evaluation, in this example, the ranking of whether the track is safer for the worker is determined based on the first angle θ_a formed by the two adjacent arms Ax and Ay among the plurality of arms A1 to A6. Do. For example, the plurality of trajectory candidates are ranked in descending order of the minimum value of the first angle θ_a. That is, ranking is performed higher in the orbit candidates where the minimum value of the first angle θ_a is larger. Alternatively, for example, the plurality of trajectory candidates are ranked in descending order of the average value of the first angles θ_a. That is, the higher the ranking of the trajectory candidates, the larger the average value of the first angles θ_a.

  The trajectory selection unit 47 selects one trajectory candidate based on the evaluation result of the evaluation unit 46 from among a plurality of trajectory candidates generated by the trajectory generation unit 45. For example, the top orbit candidate is selected. Alternatively, for example, one trajectory candidate with the highest work efficiency is selected from the trajectory candidates from the highest rank to a plurality of predetermined ranks. In this case, the good work efficiency may be determined according to an arbitrary standard. For example, the work efficiency is better when the track length is shorter or when the operation time is shorter. A good standard may be used.

  The trajectory selection unit 47 selects one trajectory candidate whose minimum value of the first angle θ_a is greater than or equal to a predetermined first threshold th_a from among a plurality of trajectory candidates generated by the trajectory generation unit 45. Also good. Furthermore, the trajectory selection unit 47 determines that the minimum value of the second angle θ_b formed by two adjacent arms that do not include at least one of the two adjacent arms Ax and the arm Ay that form the first angle θ_a is the first threshold value. One trajectory candidate that is equal to or greater than a second threshold th_b different from th_a may be selected.

  For example, the threshold value applied to the angle formed by the arm A1 and the arm A2 connected by the joint J2 may be larger than the threshold value applied to the angle formed by the arm A3 and the arm A4 connected by the joint J4. This is because the torque at the joint J2 is larger than the torque at the joint J4, so that the force applied to the object sandwiched between the arm A1 and the arm A2 is increased by making the threshold value at the joint J2 larger than the threshold value at the joint J4. This is to reduce. Similarly, the threshold value applied to the angle formed by the arm A3 and the arm A4 connected by the joint J4 may be larger than the threshold value applied to the angle formed by the arm A5 and the arm A6 connected by the joint J6.

<Processing where the control device controls the robot>
Hereinafter, a process in which the control device 30b controls the robot 20b will be described with reference to FIG. FIG. 19 is a flowchart illustrating an example of a process flow in which the control device 30b controls the robot 20b.

  The setting unit 42b sets the target position Pt (Step S51). In this example, the target position Pt is a position in the robot coordinate system RC of the control point T1 at which the end effector E can grip the object O. The setting unit 42b obtains the target position Pt based on the position Pa of the object O in the robot coordinate system RC. The position Pa of the object O in the robot coordinate system RC is previously input from the user to the control device 30b.

  The trajectory generation unit 45 generates a plurality of trajectory candidates for the movable part R to move to the target position Pt (step S52). In this example, the trajectory is a trajectory in which the control point T1 moves to the target position Pt and is a trajectory in the robot coordinate system RC.

  The evaluation unit 46 evaluates a plurality of trajectory candidates generated by the trajectory generation unit 45 (step S53). In this evaluation, in this example, the ranking of whether the track is safer for the worker is determined based on the first angle θ_a formed by the two adjacent arms Ax and Ay among the plurality of arms A1 to A6. Do.

  The trajectory selection unit 47 selects one trajectory candidate from the plurality of trajectory candidates generated by the trajectory generation unit 45 based on the evaluation result of the evaluation unit 46 (step S54). As the selection method, for example, the top trajectory candidate may be selected, or one trajectory candidate having the highest work efficiency is selected from the trajectory candidates from the top to a predetermined plurality of ranks. You may choose. Moreover, other selection methods other than that may be used as the selection method. The selection method may be input in advance to the control device 30 by the user.

  The robot control unit 41b moves the movable unit R according to the trajectory candidate (the trajectory Rt) selected by the trajectory selection unit 47 so that the position of the control point T1 coincides with the target position Pt (step S55).

  As described above, in the third embodiment, the movable part R of the robot 20b has the plurality of arms A1 to A6. The control device 30b is selected based on the first angle θ_a formed by the two adjacent arms Ax and Ay among the plurality of arms A1 to A6 among the plurality of tracks (orbit candidates) on which the movable part R moves. The robot 20b is controlled so that the movable part R is operated by the trajectory Rt. Thereby, the movable part R can be operated by the track Rt selected in consideration of the safety of the worker based on the first angle θ_a formed by the two adjacent arms Ax and Ay.

  As an example of application of the third embodiment, it may be applied to a robot having a redundant degree of freedom in a movable part. In a robot having a redundant degree of freedom in the movable part, there are innumerable trajectories in which the movable part moves to the target position. For example, in a 7-axis vertical articulated movable part that is increased by 1 axis as a redundant degree of freedom relative to a 6-axis vertical articulated movable part, there are innumerable trajectories in which the movable part moves to the target position. Further, for example, in a 5-axis SCARA robot that is increased by 1 axis as a redundancy degree with respect to a 4-axis SCARA robot, there are innumerable trajectories in which the movable part moves to the target position. A robot having a redundant degree of freedom in the movable part has an advantage that the movement of the movable part becomes smooth and interference with an object existing around the movable part can be easily avoided. A trajectory selected in consideration of the safety of the worker from among the countless trajectories in which the movable portion moves to the target position by applying the configuration of the third embodiment to the robot having redundant degrees of freedom in the movable portion. Thus, the movable part can be operated.

  In addition, you may implement combining 1st Embodiment mentioned above and 3rd Embodiment. When the first embodiment and the third embodiment are implemented in combination, the robot 20b shown in FIG. 15 further includes a force detection unit 21 shown in FIG. Further, the control device 30b shown in FIG. 18 further includes a contact detection unit 43 shown in FIG. In the control device 30b, the robot control unit 41b further has the function of the robot control unit 41 shown in FIG. 6, and the setting unit 42b further has the function of the setting unit 42 shown in FIG.

  Moreover, you may implement combining 2nd Embodiment and 3rd Embodiment which were mentioned above. When the second embodiment and the third embodiment are combined, the robot 20b illustrated in FIG. 15 further includes the object detection unit JS1 to the object detection unit JS6 illustrated in FIG. 8 at each of the joints J1 to J6. Prepare. Further, the control device 30b shown in FIG. 18 further includes an object detection processing unit 44 shown in FIG. In the control device 30b, the robot control unit 41b further has a function of the robot control unit 41a shown in FIG. 13, and the setting unit 42b further has a function of the setting unit 42a shown in FIG.

  Moreover, you may implement combining 1st Embodiment, 2nd Embodiment, and 3rd Embodiment which were mentioned above. When the first embodiment, the second embodiment, and the third embodiment are combined, the robot 20b shown in FIG. 15 further includes the force detection unit 21 shown in FIG. 1 and the object detection unit shown in FIG. JS1 to object detection unit JS7. 18 further includes a contact detection unit 43 shown in FIG. 6 and an object detection processing unit 44 shown in FIG. Further, in the control device 30b, the robot control unit 41b further has the function of the robot control unit 41 shown in FIG. 6 and the function of the robot control unit 41a shown in FIG. 13, and the setting unit 42b is further shown in FIG. And a function of the setting unit 42a shown in FIG.

  For example, when the above-described second embodiment and the third embodiment are combined or when the above-described first embodiment, the second embodiment, and the third embodiment are combined, a plurality of arms The joint JN that limits the first angle θ_a formed by two adjacent arms Ax and Ay among the arms A1 to A6 to a predetermined first threshold th_a and the object detection unit without limiting the first angle θ_a Seven joints J1 to J7 may be divided into a joint JN that detects an object by JSN.

  The embodiment of the present invention has been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and changes, substitutions, deletions, and the like are possible without departing from the gist of the present invention. May be.

  Further, a program for realizing the function of an arbitrary component in the device described above (for example, the control device 30, the control device 30a, or the control device 30b) is recorded on a computer-readable recording medium, and the program is recorded. The program may be loaded into a computer system and executed. Here, the “computer system” includes hardware such as an OS (Operating System) and peripheral devices. The “computer-readable recording medium” refers to a portable medium such as a flexible disk, a magneto-optical disk, a ROM, a CD (Compact Disk) -ROM, or a storage device such as a hard disk built in the computer system. . Furthermore, “computer-readable recording medium” means a volatile memory (RAM) inside a computer system that becomes a server or client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. In addition, those holding programs for a certain period of time are also included.

In addition, the above program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by a transmission wave in the transmission medium. Here, the “transmission medium” for transmitting the program refers to a medium having a function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line.
Further, the above program may be for realizing a part of the functions described above. Further, the program may be a so-called difference file (difference program) that can realize the above-described functions in combination with a program already recorded in the computer system.

DESCRIPTION OF SYMBOLS 1, 1a, 1b ... Robot system, 20, 20a, 20b ... Robot, 21 ... Force detection part, 30, 30a, 30b ... Control apparatus, 31 ... CPU, 32 ... Memory | storage part, 33 ... Input reception part, 34 ... Communication 35, display unit, 41, 41a, 41b ... robot control unit, 42, 42a, 42b ... setting unit, 43 ... contact detection unit, 44 ... object detection processing unit, 45 ... trajectory generation unit, 46 ... evaluation unit, 47: Orbit selection unit, A1 to A6 ... Arm, JS1 to JS7 ... Object detection unit, R ... Movable unit, O ... Object

Claims (13)

A robot with moving parts,
In the first area, which is an area where the movement area of the robot and a predetermined area overlap,
The movable part performs an operation based on a distance between the movable part and an object arranged in the first region.
robot. In the first region, the distance between the movable part and the object is a second distance shorter than the first distance as compared to the case where the distance between the movable part and the object is the first distance. If there is, the speed of the movable part is low,
The robot according to claim 1. In the first region, a third distance in which the distance between the movable part and the object is shorter than the second distance compared to the case where the distance between the movable part and the object is the second distance. The speed of the movable part is low,
The robot according to claim 2. A force detection unit for detecting a force received from an object in contact with the movable unit;
When the object comes into contact with the movable part in the first region,
When the distance between the movable part and the object is a fifth distance shorter than the fourth distance, compared to the case where the distance between the movable part and the object is a fourth distance, the movable part Reducing the force applied by the movable part to the object in contact with
The robot according to any one of claims 1 to 3. When the object comes into contact with the movable part in the first region,
Compared with the case where the distance between the movable part and the object is the fifth distance, the distance between the movable part and the object is a sixth distance shorter than the fifth distance. Reducing the force applied by the movable part to the object in contact with the part,
The robot according to claim 4. When the object comes into contact with the movable part in the first region,
In the first region, the distance between the movable part and the object is shorter than the fourth distance compared to the case where the distance between the movable part and the object is the fourth distance. If it is a distance, the threshold value for detecting the contact between the movable part and the object is small.
The robot according to claim 4 or 5. Provided in the movable part, comprising a detection part for detecting an object in a non-contact manner,
When the detection unit detects the object, the movable unit performs at least one of deceleration of the movable unit or avoidance from the object.
The robot according to any one of claims 1 to 6. When the detection unit detects that the distance between the movable unit and the object is equal to or less than a predetermined distance, the movable unit performs at least one of deceleration of the movable unit or avoidance from the object.
The robot according to claim 7. The movable part has a plurality of arms,
The movable unit is operated by a trajectory selected based on a first angle formed by two adjacent arms among the plurality of arms among the plurality of tracks on which the movable unit moves.
The robot according to any one of claims 1 to 8. In the trajectory selected based on the first angle, the first angle is equal to or greater than a predetermined first threshold value.
The robot according to claim 9. In a trajectory selected based on the first angle, a second angle formed by two adjacent arms not including at least one of the two arms is equal to or greater than a predetermined second threshold value different from the first threshold value. is there,
The robot according to claim 10. Controlling the robot according to any one of claims 1 to 11,
Control device. A robot according to any one of claims 1 to 11,
A control device for controlling the robot;
A robot system comprising:

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