JP2023090642A - Robot device, robot device control method, program, recording medium, robot device teaching method, and article manufacturing method - Google Patents

Abstract

To improve operability when a robot is moved by human hands.SOLUTION: A robot device includes a robot having a contact detection part for outputting a signal in response to contact from a user, and a control part, wherein the control part controls resistance when the robot is moved by the user, according to the number of contact parts from the user, on the basis of the signal of the contact detection part.SELECTED DRAWING: Figure 9a

Description

The present invention relates to a robot device, a control method for a robot device, and the like.

For example, in a robot device having a 6-axis articulated robot arm or the like, when installed in a manufacturing line, the trajectory (position including attitude) for driving the robot arm is taught according to the work content. At this time, the trajectory is mainly taught by operating the robot arm using a remote controller called a teaching pendant, for example. However, it is difficult to remotely control the robot arm with a remote controller, and the operability of teaching with a teaching pendant is not good.

Therefore, there has been proposed a so-called direct teaching mode in which a robot arm is directly moved manually to teach the trajectory of the robot arm. In Patent Document 1, a brake that restrains each joint so that the robot arm does not move unexpectedly is released according to the part gripped by the human hand, thereby facilitating the movement of the robot arm by the human hand. It is stated that

JP 2020-151807 A

By the way, when the robot is manually moved, it is better to use one hand for rough movement and both hands for fine movement. However, if the resistance of each joint is reduced so that the robot can be easily moved with one hand, there is a problem that the robot is too light to move with both hands, making fine adjustment difficult. On the other hand, if the joint resistance is increased in accordance with the movement of the robot with both hands, there is a problem that it becomes difficult to move the robot with one hand. Also, for example, consider a case where a user holds a teaching pendant for inputting commands to the robot with one hand and operates the robot with the other hand. The user needs to apply force with one hand to hold the teaching pendant and the other hand to operate the robot arm, which tends to cause fatigue in the hand operating the robot. There is also the problem of

SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a robot apparatus, a method for controlling the robot apparatus, and the like, which can improve operability when the robot is manually operated.

A first aspect of the present invention includes a robot having a contact detection unit that outputs a signal according to contact from a user, and a control unit, wherein the control unit detects the The robot apparatus is characterized in that resistance when the user moves the robot is controlled according to the number of contact points from the user.

A second aspect of the present invention is a robot having a contact detection unit that outputs a signal in response to contact from a user and an end effector contact detection unit that outputs a signal in response to contact of an object with an end effector; and, when the control unit detects contact of an object with the end effector by the signal from the end effector contact detection unit, the control unit detects the user for any of the links of the robot by the signal from the contact detection unit. The robot apparatus is characterized in that the end effector is controlled so that the resistance when moving the attitude of the end effector is greater than when the contact is detected.

A third aspect of the present invention is a control method for a robot apparatus comprising: a robot having a contact detection unit that outputs a signal in response to contact from a user; and a control unit, wherein the control unit detects the contact The control method is characterized by controlling the resistance when the user moves the robot according to the number of contact points from the user, based on a signal from the unit.

A fourth aspect of the present invention is a teaching method for a robot apparatus comprising: a robot having a contact detection unit that outputs a signal in response to contact from a user; and a control unit, wherein the control unit detects the contact A trajectory of the robot is obtained based on the movement of the robot by the user while controlling the resistance when the user moves the robot according to the number of contact points from the user based on the signal from the unit. , is a teaching method characterized by:

A fifth aspect of the present invention operates a robot device comprising a robot having a contact detection unit that outputs a signal in response to contact from a user, and a control unit to manufacture an article by the robot device. In the article manufacturing method, the control unit controls the resistance when the user moves the robot according to the number of contact points from the user, based on the signal from the contact detection unit. and acquiring a trajectory of the robot based on movement of the robot by means of a trajectory, and operating the robot based on the trajectory to manufacture the article.

According to the present invention, operability can be improved when a robot is manually moved.

1 is a perspective view showing a schematic configuration of a robot device according to a first embodiment; FIG. FIG. 2 is a schematic diagram showing a robot arm and contact sensors according to the first embodiment; 1 is a block diagram showing a control device for a robot device according to a first embodiment; FIG. 3 is a control block diagram showing the control system of the robot device according to the first embodiment; FIG. 4 is a flow chart when force-controlling a robot arm in the first embodiment. 4 is a flow chart for position control of the robot arm in the first embodiment. FIG. 4 is a schematic diagram showing an example of a state in which a robot arm is held and operated with one hand; FIG. 4 is a schematic diagram showing an example of a state in which a robot arm is held and operated with both hands; 4 is a flow chart when detecting a contact point using the contact sensor according to the first embodiment and executing control in a direct teach mode; 4 is a flow chart when detecting a contact point using the torque sensor according to the first embodiment and executing control in a direct teach mode. It is a schematic diagram which shows the state which hold|grips and operates a 4th link and a 6th link. FIG. 11 is a schematic diagram showing a state in which the fifth link and the sixth link are gripped and operated; FIG. 10 is a schematic diagram showing a state in which the fifth link is gripped and operated while the weight of the robot arm is supported by the third link. 7 is a graph relating to resistance when starting movement of the robot arm 251 when performing control in the direct teach mode according to the first embodiment; (a) is a schematic diagram showing a state in which the fourth link and the sixth link are held and operated, (b) is a schematic diagram showing a state in which the fourth link is released from the state of (a), (c) ) is a schematic diagram showing a state in which the third link is gripped from the state of (b). 9 is a flow chart showing control in a direct teach mode according to the second embodiment; FIG. 11 is a schematic diagram showing a state in which the sixth link is held and operated with both hands; FIG. 11 is a schematic diagram showing a state in which the sixth link is held and operated with one hand and brought into contact with an object. FIG. 4 is a schematic diagram showing a state in which the tool is held and operated with one hand; FIG. 4 is a schematic diagram showing a state in which a tool is held and operated with both hands; FIG. 11 is a schematic diagram showing a robot arm according to a fifth embodiment; FIG. 11 is a schematic diagram showing a robot arm according to a fifth embodiment; FIG. 11 is a schematic diagram showing a robot arm according to a fifth embodiment; (a) is a schematic diagram showing a teaching pendant according to a sixth embodiment. FIG. 11B is a schematic diagram of directly teaching a robot arm while holding a teaching pendant according to the sixth embodiment; FIG. 14 is a flow chart showing control in a direct teach mode according to the sixth embodiment; FIG. FIG. 12 is a schematic diagram showing a distance sensor that acquires the distance between the teaching pendant and the robot arm according to the seventh embodiment; FIG. 16 is a flow chart showing control in a direct teach mode according to the seventh embodiment; FIG. FIG. 16 is a flow chart showing control in a direct teach mode according to the eighth embodiment; FIG. 1 is a schematic diagram of a robot system when detecting a contact point using an imaging device according to an embodiment; FIG. (a) is a schematic diagram of an image from the imaging device 500 when the imaging device determines that there is one contact point. (b) is a schematic diagram of an image from the imaging device 500 when the imaging device determines that there are two contact points.

<First Embodiment>
A first embodiment for carrying out the present invention will be described below with reference to FIGS. 1 to 12. FIG. First, an overview of the robot apparatus according to the first embodiment will be described with reference to FIGS. 1 to 6. FIG.

[Configuration of robot device]
FIG. 1 is a perspective view showing a schematic configuration of a robot apparatus according to the first embodiment, and FIG. 2 is a schematic diagram showing a robot arm and contact sensors according to the first embodiment. As shown in FIG. 1 , the robot apparatus 100 includes an articulated robot 200 and a controller 300 as a controller that controls the motion of the robot 200 . The robot device 100 also includes a teaching pendant 400 as a teaching device (operation terminal) that transmits teaching data to the control device 300 . The teaching pendant 400 is operated by an operator, and is used to designate actions of the robot 200 and the control device 300 .

The robot 200 is a vertically articulated robot. Specifically, the robot 200 includes a vertically articulated robot arm 251 and a hand tool 252 as an end effector attached to the tip of the robot arm 251 . A case where the end effector is the hand tool 252 will be described below, but the end effector is not limited to this, and may be, for example, a dedicated tool for performing dedicated work. A base end of the robot arm 251 is fixed to the pedestal B. As shown in FIG. The hand tool 252 grips (supports) articles such as parts and works.

The robot 200, that is, the robot arm 251 has a plurality of joints, eg, six joints (six axes) J ₁ to J ₆ . The robot arm 251 has a plurality (six) of servo motors 201 to 206 that rotationally drive the joints J ₁ to J ₆ about the joint axes A ₁ to A ₆ , respectively.

The robot arm 251 has first to sixth links (frames) 10 to 15 rotatably connected at joints J ₁ to J ₆ . Here, the first link 10, the second link 11, the third link 12, the fourth link 13, the fifth link 14, and the sixth link 15 are connected in series in this order from the proximal side to the distal side. . The robot arm 251 can orient the hand of the robot 200 (the tip of the robot arm 251) in any three-dimensional position and any three orientations within the movable range.

The position and orientation of the robot arm 251 can be expressed in a coordinate system. A coordinate system To represents a coordinate system fixed to the base end of the robot arm 251, that is, the pedestal B, and a coordinate system Te represents a coordinate system fixed to the tip of the robot 200 (tip of the robot arm 251).

Here, the hand of the robot 200 is the hand tool 252 when the hand tool 252 does not grip (support) an object in the first embodiment. When the hand tool 252 grips (supports) an object, the robot 200 includes the hand tool 252 and the gripped (supported) object (for example, parts and tools). In other words, regardless of whether the hand tool 252 is gripping an object or not gripping an object, the tip of the robot arm 251 is referred to as the tip.

Each of the servo motors 201 to 206 includes electric motors (motors) 211 to 216 as drive sources for driving the joints J ₁ to J ₆ , respectively, and sensor units 221 to 226 connected to the electric motors 211 to 216, respectively. have. Each sensor unit 221 to 226 is a position sensor (angle sensor) 551 to 556 as a position detection unit that detects the position (angle) of each joint J ₁ to J ₆ , that is, generates a signal corresponding to the position (angle). (see FIG. 4). Further, each of the sensor units 221-226 has torque sensors 541-546 (see FIG. 4) that detect the torque of each joint J ₁ -J ₆ , that is, generate a signal corresponding to the torque. Each of the servo motors 201 to 206 has a speed reducer (not shown) and is connected to the frame driven by the joints J ₁ to J ₆ directly or via transmission members such as belts and bearings (not shown). ing.

These torque sensors 541 to 546 detect torque as driving force output by the electric motors 211 to 216 and torque as external force applied to the first to sixth links 10 to 15 of the robot arm 251. , that is, it also functions as an external force detection sensor. In addition, by detecting the external force applied to the first to sixth links 10 to 15 of the robot arm 251, it can also be made to function as a contact detection unit that detects that an object (person or object) has come into contact with those links. can.

Inside the robot arm 251, a servo controller 230 is arranged as a drive controller for controlling the driving of the electric motors 211-216 of the servo motors 201-206.

The servo control unit 230 supplies current to the electric motors 211 to 216 based on the input torque command values corresponding to the joints J ₁ to J ₆ so that the torques of the joints J1 to J6 follow the torque command values. and controls the driving of the electric motors 211-216. In the first embodiment, the servo control unit 230 is described as being composed of one control device. may be Also, in the first embodiment, the servo control unit 230 is arranged inside the robot arm 251 , but may be arranged inside the housing of the control device 300 .

Further, the robot arm 251 of the robot 200 has a plurality of brakes (for example, disk brakes) 231-236 for respectively braking the joints J ₁ -J ₆ . By operating the brakes 231 to 236, the joints J ₁ to J ₆ can be fixed so that the joints J ₁ to J ₆ do not move.

The teaching pendant 400 has a stop button 401 as a stop operation unit that transmits a stop command to the control device 300 by an operator's operation.

As shown in FIG. 2, the robot 200 includes a plurality of robots that output a signal to the control device 300 in response to contact of an object such as a person or an object with each of the first to sixth links 10 to 15 of the robot arm 251 . of contact sensors are arranged. Specifically, the first link 10 is provided with two contact sensors 710 , the second link 11 is provided with two contact sensors 711 , and the third link 12 is provided with two contact sensors 712 . The fourth link 13 is provided with two contact sensors 713 , the fifth link 14 is provided with two contact sensors 714 , and the sixth link 15 is provided with two contact sensors 715 . Furthermore, two contact sensors 716 are provided on the tip flange 16 as a connecting portion to which the hand tool 252 is attached. That is, a plurality of contact sensors are basically arranged (at least two locations) so as to form a plurality (at least two locations) on each link.

Contact sensors include contact sensors such as resistive film type and capacitance type, non-contact sensors such as ultrasonic wave type, optical (infrared) type, and electromagnetic induction type, other piezoelectric elements, force sensors such as strain gauges, etc. can be used. Among these sensors, any sensor capable of outputting a signal corresponding to an external force may have a function as a sensor for detecting external force as well as a function as a contact sensor for detecting contact with an object. Also, the arrangement of the contact sensors is an example, and may be arranged in any way. Further, the contact of an object to each of the first to sixth links 10 to 15 is detected by estimating and calculating the external force from the signals of the sensor units 221 to 226 that detect the torque of each of the joints J ₁ to J ₆ described above. You may make it In addition, a hand guide attached to a predetermined portion of the robot arm 251 and a sensor for detecting application of an external force to the hand guide may be provided. In this case, for example, since the external force is applied to the hand guide, the locations where the external force is applied to the robot arm 251 are limited.

[Configuration of control device]
Next, the control device 300 that controls the robot 200 will be described using FIG. FIG. 3 is a block diagram showing the control device of the robot device according to the first embodiment. The control device 300 is configured by a computer, and includes a CPU (Central Processing Unit) 301 as a processing unit. The control device 300 also includes a ROM (Read Only Memory) 302, a RAM (Random Access Memory) 303, and a HDD (Hard Disk Drive) 304 as storage units. The control device 300 also includes a recording disk drive 305 and various interfaces 306-309.

A ROM 302 , a RAM 303 , an HDD 304 , a recording disk drive 305 and various interfaces 306 to 309 are connected to the CPU 301 via a bus 310 . The ROM 302 stores basic programs such as BIOS. A RAM 303 is a storage device that temporarily stores various data such as the result of arithmetic processing by the CPU 301 .

The HDD 304 is a storage device for storing arithmetic processing results of the CPU 301 and various data obtained from the outside, and also records a program 330 for causing the CPU 301 to execute arithmetic processing, which will be described later. The CPU 301 executes each step of the robot control method based on a program 330 recorded (stored) in the HDD 304 .

The recording disk drive 305 can read various data and programs recorded on the recording disk 331 .

Teaching pendant 400 is connected to interface 306 . CPU 301 receives input of teaching data from teaching pendant 400 via interface 306 and bus 310 .

Servo controller 230 is connected to interface 309 . The CPU 301 acquires signals from the sensor units 221 to 226 via the servo control unit 230 , the interface 309 and the bus 310 . In addition, the CPU 301 outputs torque command value data for each joint to the servo control unit 230 via the bus 310 and the interface 309 at predetermined time intervals.

A monitor 321 is connected to the interface 307 , and various images are displayed on the monitor 321 under the control of the CPU 301 . The interface 308 is configured to be connectable with an external storage device 322 such as a rewritable non-volatile memory or an external HDD.

In the first embodiment, the HDD 304 is the computer-readable recording medium, and the HDD 304 stores the program 330. However, the present invention is not limited to this. The program 330 may be recorded on any computer-readable recording medium. For example, as a recording medium for supplying the program 330, the ROM 302, the recording disk 331, the external storage device 322, etc. shown in FIG. 3 may be used. Specific examples of recording media include flexible disks, hard disks, optical disks, magneto-optical disks, DVD-ROMs, CD-ROMs, CD-Rs, magnetic tapes, nonvolatile memories, HDDs, ROMs, and the like. can.

Although not shown in FIG. 3, the contact sensors 710 to 715 described above, angle sensors 551 to 556 and torque sensors 541 to 546 of the sensor units 221 to 226, which will be described later, are also connected to the bus 310 via interfaces. ing.

[Control system of robot device]
Next, the control system of the robot apparatus according to the first embodiment will be explained using FIG. FIG. 4 is a control block diagram showing the control system of the robot apparatus according to the first embodiment. The CPU 301 of the control device 300 functions as a force detection section 504 , a force control section 505 and a position target value generation section 506 by executing the program 330 . The servo control unit 230 includes a plurality (six because there are six joints) switching control units 511 to 516, a plurality (six because there are six joints) of position control units 521 to 526, and a plurality (six joints). Therefore, it functions as six motor control units 531 to 536).

Each sensor unit 221-226 has angle sensors (position sensors) 551-556 and torque sensors 541-546. Each angle sensor 551 to 556 is a rotary encoder (encoder) that detects the angle (position) of each electric motor 211 to 216 or each joint J ₁ to J ₆ , that is, generates a signal corresponding to the angle (position). be.

In the first embodiment, the angle sensors 551-556 directly detect the angles θ ₁ -θ ₆ of the electric motors 211-216. The angles q ₁ to q ₆ of the joints J ₁ to J ₆ can be obtained from the angles θ ₁ to θ ₆ based on the speed reduction ratio of the speed reducer (not shown). Therefore, the angle sensors 551-556 indirectly detect the angles q ₁ -q ₆ of the joints J ₁ -J ₆ .

Each torque sensor 541-546 is a sensor that detects the torque τ ₁ -τ ₆ of each joint J ₁ -J ₆ , that is, generates a signal corresponding to the torque. A plurality of angle sensors 551 to 556 constitute a position detection unit 550 which detects the position (including posture) P of the hand of the robot 200, ie, generates a signal corresponding to the position P. FIG. Further, a force detection unit 540, which is a sensor that detects a force (hand force) F acting on the hand of the robot 200 with a plurality of torque sensors 541 to 546, that is, generates a signal corresponding to the force F, is configured.

Teaching pendant 400 outputs force target value F _ref included in force teaching data 501 and position target value P _ref included in position teaching data 502 to CPU 301 by an operator's operation. The target force value F _ref is a target force value of the hand force of the robot 200 and is set by the operator using the teaching pendant 400 . The position target value P _ref is a target value for the hand position of the robot 200 and is set by the operator using the teaching pendant 400 . A robot model 503 is stored in the external storage device 322 .

Teaching pendant 400 also outputs a stop command to force control unit 505 of CPU 301 when stop button 401 is operated by the operator.

The force detection unit 504 uses signals corresponding to the torques τ ₁ to τ ₆ obtained from the torque sensors 541 to 546 and the angles q ₁ to q ₆ obtained from the angle sensors 551 to 556 to detect the current state of the hand of the robot 200. The position P(t) and the hand force F of the robot 200 at that time are obtained. At this time, force detection unit 504 obtains current position P(t) of the hand of robot 200 using signals corresponding to angles q ₁ -q ₆ obtained from angle sensors 551-556. Note that the force detection unit 504 may calculate the hand force F of the robot 200 using a force sensor (not shown) attached to the hand.

The force control unit 505 controls the robot model 503 (virtual mass M _ref ), force target value F _ref , position target value P _ref , stiffness coefficient (spring coefficient) K _ref , viscosity coefficient (damper coefficient) D _ref , current position P ( t) and a signal indicative of the value of the force F. Using these values, the force control unit 505 obtains torque command values τ _MFref1 to τ _MFref6 for the joints J ₁ to J ₆ . At this time, the force deviation between the hand force F and the force target value F _ref , the position deviation between the hand position P(t) and the position target value P _ref , the hand speed P(t)(·) and the speed target value Torque command values τ _MFref1 to τ _MFref6 are obtained so as to reduce the speed deviation from P _ref (·). The force control unit 505 outputs the calculated torque command values τ _MFref1 to τ _MFref6 to the switching control units 511 to 516 . Here, the velocity P(t)(.) is obtained by differentiating the position P(t) with respect to time, and the velocity target value P _ref (.) is obtained by differentiating the position target value P _ref with respect to time. . Therefore, in the first embodiment, the force control unit 505 obtains the speed P(t)(·) of the hand from the position P(t) of the hand, which is the detection result of the position detection unit 550 . It should be noted that the position detection unit 550 may perform calculations and output the data of the hand speed P(t)(·) itself. It also serves as a sensor that generates a signal corresponding to the speed of the hand. In addition, (·) means performing first-order differentiation with respect to time.

A position target value generation unit 506 obtains angle command values (position command values) q _ref1 to q _ref6 for each of the joints J ₁ to J ₆ by inverse kinematics calculation from the hand position target value P _ref , and obtains each angle command value q _ref1 to q _ref6 are output to the position control units 521 to 526, respectively.

Position control units 521 to 526 issue torque commands so that angle deviations between angles q ₁ to q ₆ of joints J ₁ to J ₆ and angle command values q _ref1 to q _ref6 of joints J ₁ to J ₆ are small. Obtain the values τ _MPref1 to τ _MPref6 . Reducing this angular deviation means reducing the angular deviation between the angles of the electric motors 211 to 216 and the angle command values obtained by converting the angle command values q _ref1 to q _ref6 by the reduction ratio of the speed reducer or the like. are equivalent. Position controllers 521-526 output torque command values τ _MPref1 -τ _MPref6 to switching controllers 511-516, respectively.

Each of the switching control units 511 to 516 performs switching control between a force control mode in which torque-based force control is performed and a position control mode in which position control is performed. In the force control mode, the switching control units 511 to 516 output the torque command values τ _MFref1 to τ _MFref6 to the motor control units 531 to 536 as the torque command values τ _Mref1 to τ _Mref6 . In the position control mode, the switching control units 511 to 516 output the torque command values τ _MPref1 to τ _MPref6 as the torque command values τ _Mref1 to τ _Mref6 to the motor control units 531 to 536, respectively.

Based on the angles (positions) θ ₁ to θ ₆ of the electric motors 211 to 216, the motor control units 531 to 536 control the currents Cur ₁ to Cur ₆ so as to achieve the torque command values τ _Mref1 to τ _Mref6 . Electric motors 211 to 216 are energized.

[Robot force control]
Next, force control of the robot 200 will be described. FIG. 5 is a flow chart for force control of the robot 200 in the first embodiment.

First, the operator inputs a force target value F _ref and a position target value P _ref to the teaching pendant 400 (S1). The force target value F _ref is stored in force teaching data 501 and the position target value P _ref is stored in position teaching data 502 . The position target value P _ref is the position at which the force control operation begins.

The force control unit 505 calculates torque command values (forces) τ _MFref1 to τ _MFref6 for the respective electric motors 211 to 216 using the robot model 503 so that the hand force F follows the force target value F _ref (S2). That is, the force control unit 505 calculates the torque command values (forces) τ _MFref1 to τ _MFref6 for the electric motors 211 to 216 using the robot model 503 so that the deviation between the hand force F and the force target value F _ref becomes small. do.

The switching control units 511 to 516 output the torque command values (force) τ _MFref1 to τ _MFref6 as the torque command values τ _Mref1 to τ _Mref6 to the motor control units 531 to 536 (S3).

The motor control units 531 to 536 perform energization control so as to realize the torque command values τ _Mref1 to τ _Mref6 based on the angles θ ₁ to θ ₆ of the electric motors 211 to 216 (S4).

The electric motors 211 to 216 generate joint torques τ ₁ to τ ₆ when energized (S5).

Angle sensors 551 to 556 detect angles q ₁ to q ₆ of joints J ₁ to J ₆ (angles θ ₁ to θ ₆ of electric motors 211 to 216). Torque sensors 541 to 546 detect torques τ ₁ to τ ₆ of joints J ₁ to J ₆ (S6). The angles q ₁ to q ₆ of the joints J ₁ to J ₆ and the torques τ ₁ to τ ₆ of the joints J ₁ to J ₆ are fed back to the CPU 301 of the controller 300 .

The force detection unit 504 (CPU 301) detects the torques τ 1 to _τ 6 _of the joints J ₁ to J ₆ based on the robot model 503 and the angles q ₁ to q ₆ of the joints J ₁ to J ₆ at the current position P At (t), it is converted into a hand force F applied to the hand of the robot 200 (S7). The angles θ ₁ to θ ₆ of the electric motors 211 to 216 may be used instead of the angles q ₁ to q ₆ of the joints J ₁ to J ₆ .

The CPU 301 determines whether or not the driving has ended (S8), and if it has not ended (S8: No), steps S2 to S7 are repeated. By driving the electric motors 211 to 216 according to the above flow, the force F applied to the hand of the robot 200 can be controlled to a desired force target value F _ref . Note that the order of the flow chart shown in FIG. 4 is not restrictive, and force control can be performed in other orders.

[Robot position control]
Next, position control of the robot 200 will be described. FIG. 6 is a flowchart for position control of the robot 200 in the first embodiment.

First, the operator inputs the position target value P _ref to the teaching pendant 400 (S11). The position target value P _ref is stored in position teaching data 502 .

The position target value generator 506 converts the position target value P _ref into angle command values q _ref1 to q _ref6 for the joints J ₁ to J ₆ based on the robot model 503 (S12).

The position control units 521 to 526 control the electric motors 211 to 216 so that the angles _{q 1 to} q ₆ of the joints J ₁ to J ₆ follow the angle command values q _ref1 to _{q ref6 of} the joints J 1 to J 6 . Torque command values (angles) τ _MPref1 to τ _MPref6 are calculated (S13). Angles θ ₁ to θ ₆ of the electric motors 211 to 216 may be used instead of the angles q ₁ to q ₆ as the signals indicating the angles of the joints J ₁ to J ₆ .

The switching control units 511 to 516 output the torque command values (angles) τ _MPref1 to τ _MPref6 as the torque command values τ _Mref1 to τ _Mref6 to the motor control units 531 to 536 (S14).

Note that steps S15, S16, S17, and S18 are the same as steps S4, S5, S6, and S8, and description thereof will be omitted. By driving the electric motors 211 to 216 according to the above flow, it is possible to control the hand position P of the robot 200 so as to follow the desired position target value P _ref .

Force control in steps S1 to S8 and position control in steps S11 to S18 are switched by switching control units 511 to 516, and one of the controls is selected according to the work.

[Robot direct teach mode]
Next, direct teaching in which the robot 200 is manually operated to memorize the trajectory will be described with reference to FIGS. 7 to 9b. FIG. 7 is a schematic diagram showing an example of a state in which the robot arm is held and operated with one hand, and FIG. 8 is a schematic diagram showing an example of a state in which the robot arm is held and operated with both hands. 9a and 9b are flow charts showing control of the direct teach mode according to the first embodiment. FIG. 9a is a diagram for explaining a form of acquiring information about a contact point using contact sensors 710-716. FIG. 9b is a diagram for explaining a mode of obtaining information on contact points using the torque sensors 541 to 546. FIG.

The control device 300 of the robot device 100 according to the first embodiment actually moves the robot arm 251 and teaches the trajectory when the robot device 100 is installed in a factory production line or the like. Then, the robot device 100 is operated along the taught trajectory to manufacture the article (manufacturing process). For example, by using a predetermined work and another work as materials and performing a process of assembling the predetermined work and the other work, an assembled work can be manufactured as a product. As described above, the article can be manufactured by the robot arm 251 . In this embodiment, an example of manufacturing an article by assembling workpieces by the robot arm 251 has been described, but the present invention is not limited to this. For example, the robot arm 251 may be provided with a tool such as a cutting tool or a polishing tool to process a work to manufacture an article.

When performing this teaching, a normal teaching mode and a direct teaching mode (direct teaching mode) can be executed. In normal teaching mode, the trajectory is stored while the robot arm 251 is being moved using the teaching pendant 400 . In the direct teaching mode, the trajectory is stored while the robot arm 251 is manually moved. A case where the control device 300 is executing this direct teaching mode will be described in detail below.

While the control device 300 is executing the direct teaching mode, the robot arm 251 can be operated (moved) with one hand by a teacher as shown in FIG. 7 or with both hands as shown in FIG. There are cases where it is done. Humans often use one hand when roughly operating (moving) the robot arm 251, and often use both hands when performing a precise operation.

Also, during execution of the direct teach mode (hereinafter simply referred to as “direct teach”), the control device 300 performs the above-described force control of the robot. In this case, a force target value is set, but usually only the magnitude and direction of the applied force are considered. The force target value generated according to the force detected by the human hand is determined by force control parameters (hereinafter referred to as "force control parameters"), and the force control parameters are set in advance. It is done. Therefore, for example, regardless of whether the operation is performed with one hand or with both hands, the same force target value is generated if the force detected by the hand operation is the same, unless the force control parameter is changed. . Moreover, since it takes a lot of time and effort to set force control parameters each time direct teaching is performed, conventionally, force control was executed with the set force control parameters during operation.

On the other hand, with respect to the operability of the robot arm 251, it is desirable that the robot arm 251 should move greatly with a light force for rough operation, and that it should move slightly even with a large force for precise operation. Therefore, in the first embodiment, the control shown in FIGS. 9a and 9b, which will be described below, is performed. To make it difficult to change the position/orientation of a robot when there are a plurality of locations where external forces are detected.

In the first embodiment, impedance control, which is a type of force control, will be described as an example of a technique for changing the operability of direct teaching. In impedance control, there is a virtual spring and damper between the hand position (current position) of the robot 200 and the target position, and a force based on the size of the spring and damper is generated at the hand of the robot 200. It refers to control that operates as

Assuming that the damper coefficient D, the spring coefficient K, the current position x, the target position (the fulcrum of the spring) x _d , the force target value (the force generated at the hand of the robot) F is expressed as follows.
D(x(・)−x(・) _d )+K(x−x _d )=F

In direct teaching, the target position _xd is set from the magnitude of the force applied by the human operation, and the force target value F is determined according to the damper coefficient D and the spring coefficient K. In short, the force control parameters in the first embodiment refer to the damper coefficient D and the spring coefficient K in impedance control. However, using the damper coefficient D and the spring coefficient K as the force control parameters as in the first embodiment is an example, and the force control parameters are not limited to these.

Next, direct teaching control in the first embodiment will be described with reference to FIG. 9a. When the control device 300 starts direct teaching, first, default values of various force control parameters are read (S19). The default values of various parameters read here are values set in advance by the user.

Next, the angles (positions) of the joints J ₁ to J ₆ are detected from the angle sensors 551 to 556, and the attitude of the robot arm 251 is calculated. Also, the torque applied to each joint J ₁ to J ₆ by the weight of the robot arm 251 itself is calculated from mechanical model information registered in advance (including the end effector attached to the tip of the robot). Then, in order to maintain the posture of the robot arm 251, servo control is applied to cancel the calculated torque applied to each of the joints _J1 to _J6 . (S20).

That is, if the torque sensors 541 to 546 incorporated in the joints J ₁ to J ₆ of the robot 200 are used as sensors for detecting an external force when direct teaching is performed, even when a person is not holding the robot 200 and operating it. A force due to the weight of the robot 200 is applied to the torque sensors 541 to 546, and the force is detected. It is not in line with the intention of the operator that the detected force (in this case, the weight of the robot 200) changes the position/orientation of the robot 200 even though the robot 200 is not operated by a human. In order to prevent such a problem, self-weight compensation in step S20 is performed.

Subsequently, according to the detection of each torque sensor 541-546 of each joint _J1 - _J6 , the external force acting on the first-sixth links 10-15 and tip flange 16 (that is, human operation) is detected. (S21). If no external force is detected (No in S21), it is checked whether direct teaching is continued (S24). If the execution of direct teaching is continued (Yes in S24), the process returns to step S19. The external forces acting on the first to sixth links 10 to 16 are detected not only by the respective torque sensors 541 to 546, but also by the contact sensors 710 to 716 described above, if they are capable of detecting external forces. External force may be detected from

On the other hand, when an external force acting on the first to sixth links 10 to 15 and the tip flange 16 (that is, human operation) is detected (Yes in S21), according to the contact detection by the contact sensors 710 to 716, , it is determined whether or not there are a plurality of places in contact with a person (S22). That is, it is determined whether the object is held with one hand or with both hands. If the contact is detected at one point, that is, if the object is held with one hand (No in S22), the process directly returns to step S21.

When the robot arm 251 is gripped and operated with one hand in this manner, the motor control units 531 to 536 are controlled with force control parameters of default values. That is, the electric motors 211 to 216 of the joints J ₁ to J ₆ are force-controlled, and the resistance of each joint J ₁ to J ₆ is adjusted so as to become the first resistance corresponding to the damper coefficient D and the spring coefficient K of default values. set (first resistance control). Even when the robot arm 251 is operated with one hand in this way, the angle sensors (position sensors) 551 to 556 of the joints J ₁ to J ₆ are used to control the robot arm 251 (the first link 10 to the sixth link). 15) and the position of the hand tool 252 is detected. The controller 300 stores the trajectory of the robot 200 in response to detection of this position (first teaching step).

Then, if there are a plurality of contact detection points (two points), that is, if the grip is made with both hands (Yes in S22), the damper coefficient D and the spring coefficient K of the force control parameters described above are changed (S23) (second 2 resistance control). Here, the force control parameters are changed to increase the resistance of the joints J ₁ to J ₆ , basically making it difficult to move the joints J ₁ to J ₆ and to make the first to sixth links 10 to 15 difficult to move. do. To make the joint difficult to move, the damper coefficient D of the force control parameters of the impedance control described above is set to be large. Although it is possible to make the movement difficult by increasing the spring coefficient K, the force to return to the original position is also increased, so it is not set too large in direct teaching. Therefore, in the present embodiment, the damper coefficient D is set to be larger for two-handed operation than for one-handed operation, thereby achieving operability that reflects the operator's intention. In short, each joint J ₁ to J ₆ of the robot arm 251 becomes difficult to move, and can be made to move slightly even with a large force.

When the robot arm 251 is gripped and operated with both hands in this manner, the motor control units 531 to 536 are controlled by the changed force control parameters. That is, the electric motors 211 to 216 of the joints J ₁ to J ₆ are force-controlled so that the second resistance is larger than the first resistance according to the damper coefficient D and the spring coefficient K changed from the default values. , the resistance of each joint J ₁ to J ₆ is set. Further, even when the robot arm 251 is being operated with both hands in this way, the angle sensors (position sensors) 551 to 556 of the joints J ₁ to J ₆ are used to control the robot arm 251 (the first link 10 to the sixth link). 15) and the position of the hand tool 252 is detected. Control device 300 stores the trajectory of robot 200 in response to detection of this position (second teaching step).

After that, when the state of being held with both hands changes to the state of being held with one hand (No in S22), the force control parameters are returned to default values, although not shown. If the grip with one hand and the grip with both hands are switched each time, the above control is repeated. Further, when the external force is no longer detected (No in S21), and the end of direct teaching is input through the teaching pendant 400 or the like (No in S24), direct teaching ends.

Here, in the above description, in S22 of FIG. 9a, an example is shown in which it is determined whether or not there are a plurality of places where a person is in contact according to detection of contact by the contact sensors 710-716. The sensors 541 to 546 may be used for determination. S22 will be described in detail with reference to FIG. 9b. FIG. 9b is a flow chart when performing S22 for determining the contact point using the torque sensors 541 to 546.

In FIG. 9b, when the determination of the contact point is started (when S22 is started), it is first determined based on the output value of the torque sensor 546 whether or not an external force is acting on the sixth link 15 in S22-1. Here, if an external force is acting on the sixth link 15, S22-1: Yes, and proceeds to S22-2. If no external force is acting on the sixth link 15, S22-1: No, and the process proceeds to S22-5.

In S22-2, based on the external force acting on the sixth link 15 and the current posture of the robot arm 251 acquired by the position sensors 551 to 556, the first link 10 to the fifth link 14 are controlled. Estimate the external force Based on the external force acting on the 6th link, the output values of the position sensors 551 to 556, and the link parameters of the robot arm 251, when the external force acts on the 6th link at one point, it will act on each link. Estimate the external force. In other words, the external forces to be detected by the torque sensors 541-545 are estimated.

Next, in S22-3, it is determined whether or not the external force estimated in S22-2 differs from the external force actually detected by each of the torque sensors 541 to 545 for each of the first link 10 to fifth link 14. . If the estimated external force differs from the actually detected external force on any link, it can be determined that another external force is applied to the different link. Proceeding to 4, it is determined that there are a plurality of contact points, and S22 is ended. If there is no link where the estimated external force differs from the actually detected external force, it can be determined that the external force is acting at only one point on the sixth link. Proceeding to S22-6, it is determined that there is one (single) contact point, and S22 is ended. Whether or not they are different is determined by determining whether or not the difference between the estimated external force and the detected external force exceeds a preset threshold range.

On the other hand, if the external force is not acting on the sixth link 15, in S22-5, among the links on which the external force is acting, the link closest to the tip (the sixth link 15 and the tip flange 16) is acted on. The external force applied is acquired from the output values from the torque sensors 541-545. Then, based on the external force of the link near the tip and the current posture of the robot arm 251 acquired by the position sensors 551 to 556, when the external force acts on the link at one point, it acts on the other links. Estimate the external force that would be applied. In other words, the external force to be detected by another torque sensor is estimated.

Then, in S22-3, it is determined whether or not the external force estimated in S22-5 differs from the actually detected external force for each of the other links. Since subsequent processing is as described above, description thereof is omitted.

To summarize the above control, the operator moves the robot 200 based on the location of contact from the operator (user) detected by the signals of the plurality of contact sensors 710 to 716 or the torque sensors 541 to 546 (S22). Then, the resistance is controlled (S23). In other words, the resistance when the operator changes the posture of the robot is controlled based on the (number of) points with which the operator is in contact.

[When the parts to be grasped by both hands are different]
Next, the control when the external force is detected at different locations will be described with reference to FIGS. 10 and 11. FIG. FIG. 10 is a schematic diagram showing a state in which the fourth link and the sixth link are grasped and operated, and FIG. 11 is a schematic diagram showing a state in which the fifth link and the sixth link are grasped and operated.

As shown in FIG. 10, when the operator grips the sixth link 15, the force (hand side external force) of gripping and operating the sixth link 15 is transmitted to the joint _J1 at the most proximal side. However, the force of gripping and operating the sixth link 15 is received by the fourth link 13 due to the force of the operator gripping the fourth link 13 (external force on the proximal side). is suppressed from being transmitted to the joints J ₁ to J ₃ of . Furthermore, as shown in FIG. 11 , when the operator grips the sixth link 15 and the fifth link 14 , the force of gripping and operating the sixth link 15 is received by the fifth link 14 . Transmission to the joints J ₁ to J ₄ on the proximal side of 14 is suppressed.

In such a case, since the hand side external force and the proximal side external force are detected by both hands, there is a difference in movability between the joints between the two places and the other joints. That is, the force control parameters (damper coefficient D and spring coefficient K) are set so as to make it difficult to move the other joints with respect to the movement of the joints between the two locations where the external force (contact) is being detected. In other words, the resistance when the operator changes the posture of the robot 200 is controlled based on (the position of) the point where the operator is in contact. As a result, when the operator operates with both hands, the movement of the robot 200 that comprehends the intention of the operator can be realized.

[When operating with both hands and supporting its own weight with one hand]
Next, the case where the operator operates with both hands and supports the weight with one hand will be described with reference to FIG. 12 . FIG. 12 is a schematic diagram showing a state in which the fifth link is gripped and operated while supporting the weight of the robot arm with the third link.

In the case shown in FIG. 12, for example, when the operator grabbed the fifth link 14 and operated the robot 200, he applied force in the falling direction, and immediately supported the third link 12 with the other hand. state. The hand holding the third link 12 is held to prevent the robot 200 from unintentionally falling. At this time, the external force (contact) is detected at a plurality of locations, and the torque sensor 542 of the joint _J2 that detects the proximal side external force is applied with the external force in the direction supporting the self weight of the robot 200. detected.

In such a case, it is possible to prevent an unintended drop by making it difficult to move the joints J ₁ to J ₂ closer to the base than the third link 12 where the external force on the base end is detected. Specifically, the joint torque applied to each of the joints J ₁ to J ₆ is calculated from the position/orientation of the robot 200 . Next, the joint torque detection values of the joints J ₁ to J ₂ on the proximal side of the location where the proximal external force was detected are compared with the calculated joint torque estimated values. As a result of the comparison, if the detected value is smaller than the estimated value, it is determined that the operator is supporting the fall of the robot 200, and the joints J ₁ to J ₂ move more than the other joints J ₃ to J ₆ . Set the force control parameters to make it harder. As a result, when the operator operates with both hands, the movement of the robot 200 that comprehends the intention of the operator can be realized.

[Summary of the first embodiment]
As described above, in the robot apparatus 100, when an object such as a person or an object touches the robot 200 at one point (that is, with one hand) during execution of direct teaching, the position of the robot arm 251 is moved. The resistance is controlled to be the first resistance. This control is performed by force-controlling the electric motors 211 to 216 of the joints J ₁ to J ₆ . When the object contacts the robot 200 at a plurality of points (that is, both hands), the robot arm 251 is controlled so that the second resistance is greater than the first resistance when moving the position of the robot arm 251 . Thereby, the operability can be improved whether the robot arm is moved with one hand or with both hands.

In addition, the robot apparatus 100 controls the resistance when moving the position of the robot arm 251 during execution of direct teaching to be the first resistance when the contact of the object is at one point. I do. Further, a second control step is performed to control the resistance to the second resistance when the contact of the object is at a plurality of points. Accordingly, it is possible to provide a robot control method including the first control process and the second control process.

Further, the robot apparatus 100 performs control so that the resistance when moving the position of the robot arm 251 becomes the first resistance when the contact of the object is at one point during execution of the direct teaching. A first teaching step of teaching the trajectory is performed. Further, a second teaching step is performed in which the trajectory of the robot 200 is taught by controlling so as to provide the second resistance when the object touches at a plurality of points. Accordingly, it is possible to provide a robot teaching method including the first teaching step and the second teaching step. Furthermore, in addition to the first teaching process and the second teaching process, the manufacturing of the article includes a manufacturing process of manufacturing the article by operating the robot arm on the trajectory memorized by the first teaching process and the second teaching process. can provide a method.

In the first embodiment, the control is performed so that the second resistance when both hands are in contact is greater than the first resistance when one hand is in contact. However, the control is not limited to this, and the size is not limited as long as the control is such that the first resistance and the second resistance are different. For example, when operating the robot 200 with both hands, it is possible to easily adjust the position and posture by increasing the resistance on the proximal side to make it difficult to move and decreasing the resistance on the distal side to less than the first resistance. Conceivable.

Further, in the above-described embodiment, the resistance of each joint J ₁ to J ₆ is changed depending on whether or not there are a plurality of places in contact with the person. However, when an external force is applied by direct teaching, for example, the relationship between the external force acting on the link and the amount of movement of the robot arm is set as shown in FIG. In some cases, control is also performed so that the is not moved. In such a case, the threshold may be changed depending on whether there are a plurality of contact points. Specifically, when there are a plurality of contact detection points (two points), that is, when the object is held with both hands, the threshold value is set larger than the default value, and when there is one contact detection point, that is, when the object is held with one hand, the threshold value is set larger than the default value. If so, set the value to be smaller than the default value. As a result, when the robot arm 251 is operated with both hands, the movement of the robot arm 251 can be made heavy, and when the robot arm 251 is operated with one hand, the movement of the robot arm 251 can be lightened. It is possible to improve the operability.

<Second embodiment>
Next, a second embodiment, which is a partial modification of the first embodiment, will be described with reference to FIGS. Fig. 14(a) is a schematic diagram showing a state in which the fourth link and the sixth link are gripped and operated, and Fig. 14(b) is a schematic diagram showing a state in which the fourth link is released from the state of (a). FIG. 14(c) is a schematic diagram showing a state in which the third link is gripped from the state of (b). FIG. 15 is a flow chart showing control of the direct teach mode according to the second embodiment. In addition, in the description of the second embodiment, the same reference numerals are used for the same parts as in the first embodiment, and the description thereof will be omitted.

In the robot apparatus 100 according to the second embodiment, the control performed when the robot 200 is held with both hands and held with one hand is changed from that of the first embodiment. . For example, as shown in FIG. 14(a), the operator releases the grip of the fourth link 13 from the state in which the operator grips the fourth link 13 and the fifth link 14 with both hands, and Thus, only the fifth link 14 is held by one hand. After that, as shown in FIG. 14(c), the third link 12 is gripped with the hand released from the fourth link 13, and the third link 12 and the fifth link 14 are gripped with both hands. In this way, when the operator changes the position/orientation of the robot 200, it is likely that the gripping part will be changed.

However, for example, as shown in FIG. 14B, there occurs a moment when the external force is temporarily detected at one location. If the force control parameter is changed immediately due to a temporary change in state, and the joint resistance that makes it difficult to change the position and posture of the robot is changed immediately, it may be difficult for the operator to grasp the operation feeling. Therefore, in the second embodiment, the control shown in FIG. 15 below is performed, and the force control parameter is appropriately set.

In the second embodiment, when the control device 300 starts direct teaching, first, the default values of various force control parameters are read, and the value of the counter N is set to 1 (S25).

Next, the angles (positions) of the joints J ₁ to J ₆ are detected from the angle sensors 551 to 556, and the attitude of the robot arm 251 is calculated. Also, the torque applied to each joint J ₁ to J ₆ by the weight of the robot arm 251 itself is calculated from mechanical model information registered in advance (including the end effector attached to the tip of the robot). Then, in order to maintain the posture of the robot arm 251, servo control is applied so as to cancel the calculated torque applied to each of the joints J ₁ to J ₆ (self-weight compensation). Torque is output (S26).

Subsequently, according to the detection of each torque sensor 541-546 of each joint _J1 - _J6 , the external force acting on the first-sixth links 10-15 and tip flange 16 (that is, human operation) is detected. (S27). If no external force is detected (No in S27), it is checked whether direct teaching is continued (S33). If the execution of direct teaching is continued (Yes in S33), the process returns to step S25. The external forces acting on the first to sixth links 10 to 16 are detected not only by the respective torque sensors 541 to 546, but also by the contact sensors 710 to 716 described above, if they are capable of detecting external forces. External force may be detected from

On the other hand, if an external force acting on the first to sixth links 10 to 15 and the tip flange 16 (that is, human operation) is detected (Yes in S27), the process proceeds to step S28. Here, only when the value of the counter N is greater than a set value (for example, 5), the damper coefficient D and the spring coefficient K of the force control parameters are set to the default values for one position (for one hand), If the value of the counter N is equal to or less than the set value, the force control parameters are not changed (S28).

Subsequently, it is determined whether or not there are a plurality of places touched by a person according to detection of contact by the contact sensors 710 to 716 (S29). That is, it is determined whether the object is held with one hand or with both hands. If there are multiple (two) contact detection points, that is, if the object is held with both hands (Yes in S29), the damper coefficient D and spring coefficient K of the force control parameters are changed for multiple points (S31). In other words, when the robot is held with both hands, the resistance of each joint J ₁ to J ₆ is set so that the force control parameter is changed to become the second resistance, making it difficult to move each joint J ₁ to J ₆ . To make the first to sixth links 10 to 15 difficult to move. Then, the counter N is reset (S32), and the process returns to step S27.

It should be noted that even when the robot arm 251 is being operated with both hands in this manner, the angle sensors (position sensors) 551 to 556 of the joints J ₁ to J ₆ are used to control the robot arm 251 (the first link 10 to the sixth link). 15) and the position of the hand tool 252 is detected. Control device 300 stores the trajectory of robot 200 in response to detection of this position (second teaching step).

On the other hand, if the contact is detected at one point, that is, if the object is held with one hand (No in S29), 1 is added to the counter N (S30), and the process returns to step S27. In other words, the state where the robot arm 251 is gripped with both hands changes to the state where it is gripped with one hand, but until the value of the counter N becomes larger than the set value (for example, 5), the force control parameters are set for a plurality of locations. It remains set (see S31). Then, the determination in step S29 and step S30 are repeated in a control cycle, and the counter N becomes larger than the set value (for example, 5) after the set time has passed (for example, after several seconds). Then, the force control parameter is set for one position, and switching is performed so that the resistance of each joint J ₁ to J ₆ is set to the first resistance. That is, the joints J ₁ to J ₆ are made easier to move, and the first to sixth links 10 to 15 are made easier to move.

Even if the state of being gripped with both hands temporarily changes to the state of being gripped with one hand in this way, each joint J ₁ to J ₆ remains difficult to move until a set time (for example, several seconds) elapses. This prevents the robot arm 251 from suddenly becoming lighter when the operator grips one hand again as described above, so that the operator can easily grasp the operation feeling.

Note that when the robot arm 251 is gripped and operated with one hand in this manner, even if the resistance of each joint J ₁ to J ₆ is the second resistance, each joint J ₁ to J ₆ may be the first resistor. However, even between these, the positions of the robot arm 251 (first link 10 to sixth link 15) and the hand tool 252 are detected by angle sensors (position sensors) 551 to 556 of the joints J ₁ to J ₆ . . Then, the control device 300 stores the trajectory of the robot 200 according to the detection of this position. In the second embodiment, when the resistance of each of the joints J ₁ to J ₆ is the second resistance, the teaching is the second teaching step, and the resistance of each of the joints J ₁ to J ₆ is the first resistance. Teaching in the case of the first teaching step constitutes a first teaching step.

After that, the external force is no longer detected (No in S27), and when the end of direct teaching is input by, for example, the teaching pendant 400 (No in S33), direct teaching ends. Note that the present embodiment and modified examples may be combined with the various embodiments and modified examples described above.

As described above, the control of the present embodiment can be summarized as follows. The resistance is controlled (No in S29, S31). In other words, the resistance when the operator changes the posture of the robot is controlled based on the (number of) points with which the operator is in contact.

<Third Embodiment>
Next, a third embodiment obtained by partially modifying the first and second embodiments will be described with reference to FIGS. 16 and 17. FIG. FIG. 16 is a schematic diagram showing a state in which the sixth link is held and operated with both hands, and FIG. 17 is a schematic diagram showing a state in which the sixth link is held and operated with one hand and brought into contact with an object. In the description of the third embodiment, the same reference numerals are used for the same parts as in the first and second embodiments, and the description thereof will be omitted.

Unlike the first and second embodiments, the third embodiment is provided with a plurality of contact sensors in the same link. The control in the case of contact will be described. That is, in the robot 200 according to the third embodiment, two contact sensors 710 to 716 are arranged on the surface of each of the first to sixth links 10 to 15 and the tip flange 16, as shown in FIG. It is assumed that These contact sensors 710 to 716 are preferably arranged so that the operator cannot touch both of them with one hand at the same time (it is difficult to touch them). Three or more contact sensors may be arranged for one link. Furthermore, even if one contact sensor is arranged for one link, the size and distribution of the contact area can be used to determine whether the operation is performed with one hand, with both hands, or with other operations. Any configuration can be used.

As shown in FIG. 16, when the operator holds and operates the same link (sixth link 15 in FIG. 16) with both hands, he/she is often performing a fine operation (fine adjustment). Humans are not good at continuously applying the same force in a certain direction, and since the operation is accompanied by camera shake, the device may meander to some extent when moving toward the target position/posture. When fine manipulation (fine adjustment) is required when direct teaching is performed, the target position/orientation is often close to the target. Therefore, when operating the same link with both hands, the resistance when moving the link gripped with both hands is greater in all directions than when different links are gripped with both hands. Change force control parameters. As a result, the influence of unstable force components due to camera shake can be reduced, and the operability of the robot 200 can be increased so that it is difficult to overshoot the target.

Further, as shown in FIG. 17, the force control parameter is similarly changed so that the resistance increases when the object 900 is touched while the link (the sixth link 15 in FIG. 17) is gripped with one hand. do. In particular, it is preferable to change the force control parameter so that the resistance is greater than when different links are gripped with both hands as described above. As a result, when the robot 200 comes into contact with the object 900, the operability of the robot 200 becomes difficult, so that it becomes difficult for the robot 200 to sink into the object 900 any further. Note that the present embodiment and modified examples may be combined with the various embodiments and modified examples described above.

<Fourth Embodiment>
Next, a fourth embodiment obtained by partially modifying the above first to third embodiments will be described with reference to FIGS. 18 and 19. FIG. FIG. 18 is a schematic diagram showing a state in which the tool is held and operated with one hand, and FIG. 19 is a schematic diagram showing a state in which the tool is held and operated with both hands. In the description of the fourth embodiment, the same reference numerals are used for the same parts as in the first to third embodiments, and the description thereof will be omitted.

In the fourth embodiment, unlike the first to third embodiments, a hand tool 252 is attached to the tip flange 16 of the robot 200, and the control when the operator grips and operates the hand tool 252 will be described. do. That is, in the robot 200 according to the fourth embodiment, a contact sensor as an end effector contact detection section (not shown) is arranged on the surface of the hand tool 252 or on the connecting portion of the tip flange 16 of the hand tool 252. is assumed. A torque sensor can also be substituted for this contact sensor.

As shown in FIG. 18, during execution of direct teaching, when the operator holds and operates the hand tool 252 with one hand (or both hands), the hand tool 252 is placed on the work to be worked. alignment is often performed. In this case, it is not preferable to change the posture of the hand tool 252, that is, the angle of the tip flange 16.

Furthermore, as shown in FIG. 19, when the hand tool 252 is gripped with both hands and the tool is opened and closed during direct teaching, the robot arm 251 receives the force associated with the opening and closing operation. put away. When performing operations such as opening and closing the tool of the hand tool 252, it is often the case that the work plane (position and posture in some cases) for approaching the work 910, which is the work object, is fixed. Therefore, it is not preferable that the angle of the tip flange 16 of the robot arm 251 is changed when the operator operates the tool of the hand tool 252 .

Therefore, a contact sensor arranged on the surface of the hand tool 252 or at the connecting portion of the hand tool 252 of the tip flange 16 detects that an external force is being applied to the hand tool 252 or that the hand tool 252 is being gripped and operated. to detect Then, when contact with the hand tool 252 is detected, the force control parameters are changed as described above. As a result, the resistance of each of the joints J ₁ to J ₆ is increased and the tip flange 16 moves in the direction in which the angle changes compared to when the contact (external force) is detected by the first link 10 to the sixth link 15 . make it difficult In this case, the resistance in the direction in which the angle of the tip end flange 16 changes should be greater than the first resistance when the first to sixth links 10 to 15 are held with one hand. Preferably, the resistance in the direction in which the angle of the tip flange 16 changes is preferably greater than the second resistance when the first link 10 to the sixth link 15 are gripped with both hands. As a result, when the operator holds the hand tool 252 with one hand or both hands and performs direct teaching, the work plane relationship between the workpiece 910 and the hand tool 252 can be maintained. Therefore, it is possible to facilitate adjustment such as alignment between the hand tool 252 and the workpiece 910 by the operator.

In addition, in the above-described fourth embodiment, when contact with the hand tool 252 is detected, the content of changing the force control parameter to change the operability has been described. However, the control change method is not limited to this. For example, it is also possible to perform position control such that the hand tool 252 operates in the direction in which the external force is detected, with a movement amount set in advance as an operation unit. The operability at this time may be changed by adjusting the amount of movement. Note that the present embodiment and modified examples may be combined with the various embodiments and modified examples described above.

<Fifth Embodiment>
Next, a fifth embodiment, which is a partial modification of the first to fourth embodiments, will be described with reference to FIG. FIG. 20 is a schematic diagram showing a robot arm 251, handles 811 to 816, and contact sensors 821 to 826 according to the fifth embodiment. In the description of the fifth embodiment, the same reference numerals are used for the same parts as in the first to fourth embodiments, and the description thereof will be omitted.

As shown in FIG. 20, each of the first to sixth links 10 to 15 of the robot arm 251 has a plurality of (at least two) handles 811 to 816 for moving the robot arm 251 during direct teaching. are provided. Also, the handle has a different color from each link. Contact sensors 821 to 826 are provided on the portions of the handles 811 to 816 (portions that are gripped by the user), respectively. Since the handle with the contact sensor is provided, the user can grasp any one of the handles 811 to 816 of the robot arm to perform direct teaching. Therefore, the contact sensors 821 to 826 can reliably detect where the user is in contact with the robot arm 251 .

Also, each link has two or more handles, and each handle is provided with a contact sensor. Therefore, based on the output value of the contact sensor, when the user touches the robot arm 251 with one hand, when the user touches the same link with both hands, and when each hand touches a different link and can be easily distinguished. Therefore, the robot can appropriately change the force control parameters (damper coefficient D, spring coefficient K, etc.) and control the resistance of each joint J ₁ to J ₆ according to the manner of contact.

In this embodiment, the handle is not attached to the hand tool 252 portion, but a handle having a contact sensor may also be attached to the hand tool 252 portion. In addition, to prevent the operator from moving the robot arm by grabbing a link part other than the handle, as shown in FIG. A note (instruction part) and an arrow may be displayed to call the operator's attention. Also, as shown in FIG. 22, an indicator may be provided on each of the handles 811 to 816 so that the user can grasp a predetermined portion by lighting the indicator. Note that the present embodiment and modifications may be combined with the various embodiments and modifications described above.

<Sixth Embodiment>
Next, a sixth embodiment obtained by partially modifying the above first to fifth embodiments will be described with reference to FIGS. FIG. 23(a) is a diagram for explaining a situation in which the robot arm 251 is directly taught while holding the teaching pendant 410, and FIG. 23(b). FIG. 24 is a flow chart showing control of the direct teach mode according to the sixth embodiment.

As illustrated in FIG. 23(a), a teaching pendant 410 has a display screen 411, an emergency stop button 412, and an operation panel 413 on its surface, and a three-position enable button 414 on its side. ing. This three-position type enable button 414 is a button that turns off when no operation is performed, turns on when pressed lightly, and turns off when pressed more strongly. It is similar to the one installed in the device. Then, as shown in FIG. 23(b), when the user operates the robot arm 251 with the enable button 414 lightly pressed, the user often operates with one hand. Therefore, when performing direct teaching while lightly pressing the enable button 414, the robot arm is operated with one hand, and the user is likely to get tired.

Next, direct teaching control in the sixth embodiment will be described with reference to FIG. In order to simplify the explanation, the explanation of the same processing as in the various embodiments described above will be omitted.
From FIG. 24, after S20, in S41, it is determined whether the enable button 414 of the teaching pendant 410 is ON. If the enable button 414 is not turned on (No in S41), the processing relating to the robot arm operation based on external force detection is not performed, and the process proceeds to S24 to confirm whether or not direct teaching is continuing. If the execution of direct teaching is continued (Yes in S24), the process returns to step S19. If the execution of direct teaching is not continued (No in S24), the direct teaching process is terminated.

In S41, if the enable button of teaching pendant 410 is ON (Yes in S41), the process proceeds to S21. Then, according to the detection of each torque sensor 541-546 of each joint _J1 - _J6 , the external force acting on the first to sixth links 10-15 and tip flange 16 (that is, human operation) is detected. . When the external force is not detected (No in S21), the process proceeds to step S24 described above.

If an external force (that is, a human operation) is detected (Yes in S21), the process proceeds to S22, and the human contact is detected according to the detection of contact by the contact sensors 710 to 716 or the output values of the torque sensors 541 to 546. It is determined whether or not there are a plurality of (two) locations. If there are a plurality of contact detection points (Yes in S22), the process returns to step S41.

On the other hand, if there is a single contact detection point (one point), that is, if the robot arm 251 is operated with one hand while operating the teaching pendant 410 (No in S22), the process proceeds to step S23. Then, in S23 in this embodiment, the damper coefficient D and the spring coefficient K of the force control parameters described above are changed so as to correspond to values (third resistance) made smaller than the default values. That is, the control is changed so that the robot arm 251 can be easily moved by the user. Then, it returns to immediately before step S41 and repeats the above-described processing.

Although illustration is omitted as in FIG. 9A, in FIG. 24 as well, when the state of operation with one hand changes to the state of operation with both hands (Yes in S22), the force control parameter is changed to the default value. back to Further, in the present embodiment, the user's contact point on the robot arm 251 is detected in S22, but S22 may be omitted and the process may proceed to S23. This is because, as shown in FIG. 23B, in direct teaching with the enable switch turned ON, the robot arm is often operated with one hand.

As described above, in the sixth embodiment, only when the enable button 414 of the teaching pendant 410 is ON, it is possible to operate the robot arm 251 according to the action of an external force, thereby unintentionally moving the robot arm 251. You can reduce the danger. It is also possible to reduce fatigue of the user operating the robot arm 251 with one hand. Therefore, the operability can be improved whether the robot arm is moved with one hand or with both hands. Note that the present embodiment and modifications may be combined with the various embodiments and modifications described above.

<Seventh Embodiment>
Next, a seventh embodiment obtained by partially modifying the first to sixth embodiments will be described with reference to FIGS. 25 and 26. FIG. FIG. 25 is a diagram showing a robot arm 251 and a teaching pendant 410 in the seventh embodiment. FIG. 26 is a flow chart showing control of the direct teach mode according to the seventh embodiment. In order to simplify the description, the description of the same processing as in the above-described embodiment will be omitted.

As shown in FIG. 25, in the seventh embodiment, distance sensors 901 and 902 that wirelessly detect the distance between the teaching pendant 410 and the robot arm 251 are mounted, and depending on the measured distance, force is applied as described later. Change control parameters. A distance sensor 901 is provided on the teaching pendant 410 , and a distance sensor 902 is provided at a position (first link 10 ) that does not move due to a change in posture of the robot arm 251 . The acquired distance information is transmitted from teaching pendant 410 or robot arm 251 to control device 300 .

As a specific example of the distance sensor, the distance sensor 901 is equipped with radio wave transmitting means, the distance sensor 902 is equipped with radio wave receiving means, and the radio wave receiving means detects the distance by measuring the strength of the radio waves transmitted from the radio wave transmitting means. It should be configured to Conversely, the distance sensor 901 may be equipped with radio wave receiving means, and the distance sensor 902 may be equipped with radio wave transmitting means. Of course, other means may be used as long as the distance between the teaching pendant 410 and the robot arm 251 can be detected.

From FIG. 26, following S20, in S41, it is determined whether the enable button 414 of the teaching pendant 410 is ON. If the enable button 414 is not turned on (No in S41), the processing relating to the robot arm operation based on external force detection is not performed, and the process proceeds to S24 to confirm whether or not direct teaching is continuing. If the execution of direct teaching is continued (Yes in S24), the process returns to step S19. If the execution of direct teaching is not continued (No in S24), the direct teaching process is terminated.

If the enable button 414 of the teaching pendant 410 is ON (Yes in S41), the process proceeds to S21, and the first to sixth links 10 to 15 and the tip flange 16 are acted on based on the respective torque sensors 541 to 546. Detect external force (i.e., human operation). If no external force is detected (No in S21), the process proceeds to step S24 described above. If an external force (i.e., human operation) is detected (Yes in S21), the process proceeds to S42 to detect (acquire) the distance between the teaching pendant 410 and the robot arm 251 and determine if the distance is within a predetermined threshold range. determine whether

If the distance is within the range of the threshold value in S42 (Yes in S42), the process proceeds to S43, and according to the detection of the contact point by the contact sensors 710 to 716 or the torque sensors 541 to 546, the point where the person is in contact is determined. is plural. If two contact points are detected, that is, if the operation is performed with both hands (Yes in S43), the process returns to step S41.

On the other hand, if there is a single contact detection point (one point), that is, if the operation is performed with one hand (No in S43), the process proceeds to S44, and the damper coefficient D and spring coefficient K of the force control parameters are set to the third resistance (default value). That is, the robot arm 251 is made easier to move by the user. Then, it returns to S41 and repeats the above-described processing.

If the distance is not within the range of the threshold value in S42 (No in S42), the process proceeds to S45, and according to the detection of contact by the contact sensors 710 to 716 or the torque sensors 541 to 546, the point where the person is in contact is determined. is plural. If the contact is detected at one point, that is, if the operation is performed with one hand (No in S45), proceed to S47 so that the damper coefficient D and the spring coefficient K of the force control parameters correspond to the first resistance value (default value). change to Then, the process returns to S41 and repeats the above-described processing.

On the other hand, if there are a plurality of contact detection points (two points), that is, if the operation is performed with both hands (Yes in S45), the process proceeds to S46, and the damper coefficient D and spring coefficient K of the force control parameters are set to the second resistance (default value greater than the value). That is, it is made difficult for the user to move the robot arm 251 . Then, it returns to S41 and repeats the above-described processing.

As described above, in the seventh embodiment, the difficulty (or ease of movement) of the robot arm 251 can be changed according to the distance between the teaching pendant 410 and the robot arm 251 . In S44, since the teaching pendant 410 exists near the robot arm 251 and the operator operates with one hand, the operator may be operating the robot arm 251 with one hand while holding the teaching pendant 410. can be determined to be high. Therefore, the force control parameter is set so as to correspond to the third resistance, which is the most easily movable value. By doing so, it is also possible to reduce fatigue of the user operating the robot arm 251 with one hand.

In S46, it can be determined that the teaching pendant 410 is not in the vicinity of the robot arm 251 and that the operator is in contact with both hands. Therefore, it can be determined that there is a high possibility that someone other than the operator is holding the teaching pendant 410 and the operator is operating the robot arm 251 with both hands without holding the teaching pendant 410 . Therefore, the force control parameter is set to correspond to the second resistance, which is the most difficult value to move. By doing so, it becomes easier for the operator to perform operations such as precisely moving the robot arm 251 by a minute distance using both hands, and the operability when operating the robot arm 251 with both hands can be improved. .

In S47, it can be determined that the teaching pendant 410 is not in the vicinity of the robot arm 251 and that the operator is in contact with one hand. Therefore, it can be determined that there is a high possibility that someone other than the operator is holding the teaching pendant 410 and the operator is operating the robot arm 251 with one hand without holding the teaching pendant 410 . Therefore, the force control parameter is set to correspond to the first resistance (default value). By doing so, it is possible to reduce the possibility that the operator will excessively move the robot arm 251 because it is too easy to move, causing the robot arm 251 to come into contact with someone other than the operator. In addition, since it can be determined that the operator is operating the robot arm 251 without holding the teaching pendant 410, even if it is the first resistance, fatigue can be suppressed to some extent.

As described above, in addition to the contact point of the operator, by combining the distance between the teaching pendant 410 and the robot arm 251 to appropriately change the difficulty (or ease of movement) of the robot arm 251, more flexible resistance setting is possible. It becomes possible. In the above description, the force control parameter is changed according to two conditions, that is, whether the distance between the teaching pendant 410 and the robot arm 251 is within the range of the threshold value or not. Accordingly, it is also possible to adopt a configuration in which the force control parameter is changed step by step. Although illustration is omitted in the same manner as in FIG. 9(a), when the state of operation with one hand changes to the state of operation with both hands (Yes in S43) in FIG. return. Note that the present embodiment and modified examples may be combined with the various embodiments and modified examples described above.

<Eighth Embodiment>
Next, an eighth embodiment obtained by partially modifying the above first to seventh embodiments will be described with reference to FIG. FIG. 27 is a flow chart showing control of the direct teach mode according to the eighth embodiment. In order to simplify the explanation, the explanation of the same processing as in the various embodiments described above will be omitted.

When the control device 300 starts direct teaching control, first, in S51, the control device 300 uses the teaching pendant 410 to prompt the operator to enter an ID (operator identification information). When the ID is entered in S51, the user list stored in advance in the control device 300 is referred to in S52 to search for the ID entered in S51.
Although the ID is used as the identification information in this embodiment, the means for authenticating the operator is not limited to this. For example, an IC tag may be used. Also, a one-dimensional barcode or a two-dimensional barcode may be used. Examples of one-dimensional barcodes include JAN, CODE39, Code128, ITF, NW7, and the like. Examples of two-dimensional barcodes include QR code (registered trademark) and DataMatrix. A data writable card and a card reader for reading information on the card may also be used. Alternatively, an imaging device capable of recognizing the operator's face may be used, and the operator may be authenticated using face information as identification information. In addition, the robot system is equipped with an interface that can acquire iris information, brain waves, blood flow patterns, fingerprint information, etc. of the operator, and biological information such as iris information, brain waves, blood flow patterns, fingerprint information, etc. is used as identification information. I don't mind.

Next, in S53, it is determined whether or not there is an ID that matches the ID input in S51 in the user list. If there is a matching ID (Yes in S53), the process advances to S54 to read the force control parameter corresponding to the first resistance stored in advance in association with the ID. Then, the process proceeds to S20, in which robot self-weight compensation is performed, but since the process is the same as that of S20 in the above-described embodiment, the description is omitted here. If there is no matching ID in the user list (No in S53), proceed to S55, load the force control parameters corresponding to the first resistance for default, and then perform robot self-weight compensation in S20. conduct.

The first resistance stored in association with each operator's ID is set according to, for example, the operator's physical strength and physique. When the operator is strong, the first resistance corresponding to the operator's ID is set higher than the default first resistance. Conversely, if the operator is weak, the first resistance corresponding to the operator's ID is set lower than the default first resistance. Further, the standard for setting the first resistance is not limited to the strength of the operator's force. For example, the first resistance corresponding to each operator's ID may be set according to the skill of each operator. .

Then, in S21, according to the detection of each torque sensor 541-546 of each joint _J1 - _J6 , the external force acting on the first to sixth links 10-15 and the tip flange 16 (that is, the operation by a person) is detected. ). If no external force is detected (No in S21), the process proceeds to S24 to determine whether or not direct teaching is continued. If the execution of direct teaching is continued (Yes in S24), the process returns to step S53. If the execution of direct teaching is not continued (No in S24), the direct teaching process is terminated.

On the other hand, if an external force (that is, a human operation) is detected in S21 (Yes in S21), the process proceeds to S22. It is determined whether or not there are multiple locations. If one contact is detected, that is, if the operation is performed with one hand (No in S22), the process returns to S21.

On the other hand, if there are multiple contact detection points (two points), that is, if the user is operating with both hands (Yes in S22), the process advances to S56 to check again whether or not there is a matching ID in the user list. . Then, if a matching ID exists (Yes in S56), the process proceeds to S57, where the second resistor for the ID stored in advance (which is larger than the first resistor for the ID) is matched. The force control parameters are read, and the process returns to S21. If there is no matching ID in the user list (No in S56), proceed to S58 to read the force control parameter corresponding to the default second resistance (which is larger than the default first resistance). Then, the process returns to step S21 to repeat the above process.

The second resistance stored in association with each operator's ID is set, for example, according to the operator's physical strength and physique. When the operator is strong, the second resistance corresponding to the operator's ID is set higher than the default second resistance. Conversely, if the operator is weak, the second resistance corresponding to the operator's ID is set lower than the default second resistance. Further, the reference for setting the second resistance is not limited to the strength of the operator's force. For example, the first resistance corresponding to each operator's ID may be set according to the skill level of each operator.

As described above, in the eighth embodiment, by confirming the ID, the robot is controlled using the force control parameter corresponding to each operator. When a specific operator operates with one hand, the force control parameter is set to correspond to the one-handed first resistance corresponding to the specific operator. When a specific operator operates with both hands, the force control parameter corresponding to the second resistance for both hands, which is a larger value than that for one hand, is set for the specific operator. As a result, it is possible to make the ease and difficulty of moving the robot arm 251 suitable for the operator according to the operator's unique information such as the operator's physical strength, physique, and skill level. becomes.
Although illustration is omitted in the same manner as in FIG. 9a, when the state of operation with both hands changes to the state of operation with one hand in FIG. back to the force control parameters corresponding to . However, in the eighth embodiment, if the ID exists in the list, the force control parameter corresponding to the first resistance for that ID is restored, and if the ID does not exist in the list, the force control parameter corresponding to the default first resistance is returned. Return to control parameters. Note that the present embodiment and modifications may be combined with the various embodiments and modifications described above.

<Possibility of Other Embodiments>
In the above-described first to eighth embodiments, the force control parameter is changed when the contact sensor detects contact at two points (operator's grip or contact with an object). However, the present invention is not limited to this, and for example, two or more operators may operate, so it is conceivable to change the force control parameter by contact at two or more locations (multiple locations).

Further, in the first to eighth embodiments, it has been described that when the contact person touches a plurality of places, the force control parameters are changed from the case of contact at one place. However, on the contrary, the force control parameters for contact at a plurality of locations may be set as default values, and the force control parameters may be changed when contact at one location is detected.

Further, in the first to eighth embodiments, the robot arm has been described as an example of a 6-axis articulated robot arm, but the present invention is not limited to this. That is, the number of joints can be any number. Furthermore, although the tip flange that connects the end effector has been described as being fixed to the sixth link, a joint may be further provided between the connecting portion of the end effector. Therefore, this connecting portion can also be considered as one of the links.

Also, in the first to eighth embodiments, the hand tool 252 was described as an example of the end effector, but the end effector is not limited to this, and any tool or device may be used. For example, it may be a polishing tool for polishing a workpiece, a cutting tool for cutting, or a welding tool for welding. Moreover, it may be a driver tool for screw tightening or the like.

Further, in the first to eighth embodiments, the contact sensors 711 to 715 or the torque sensors 541 to 546 are used as contact detection units, but the present invention is not limited to this. For example, as shown in FIG. 28, an imaging device 500 installed at a position where the robot arm 251 can be imaged may be used to acquire the contact point of the robot arm 251 by the user. In FIG. 28 , the imaging device 500 is connected to the control device 300 , and the control device 300 includes an image processing section that performs image processing on the image acquired from the imaging device 500 . This time, a configuration in which an image processing unit is provided for the control device 300 will be described as an example, but a configuration in which an image processing device is provided separately from the control device 300 may be employed.

29(a) and 29(b) exemplify captured images when acquiring the contact location on the robot arm 251 based on the image from the imaging device 500. FIG. FIG. 29(a) is an example of an image when it is determined that there is one contact point, and FIG. 29(b) is an example of an image when it is determined that there are two contact points. Preferably, the color of the robot arm 251 and the background on which the robot arm 251 is arranged is different from the color of the user's hand. For example, when the user operates the robot arm 251 with bare hands, the color of the robot arm 251 and the background on which the robot arm 251 is arranged should be a different color from the skin color of the user. Alternatively, the user may wear gloves of a color different from the color of the robot arm 251 and the background on which the robot arm 251 is arranged.

By doing so, the image processing unit performs known edge extraction processing on the image acquired from the image pickup device 500, so that as shown in FIGS. 29A and 29B, can easily obtain the approximate position of the user's hand in the As illustrated in FIGS. 29(a) and 29(b), it is also possible to display an image showing the rough position of the user's hand with the marker 501 on the monitor 321 during the direct teaching of the robot arm 251. be. Then, based on the approximate positions and number of the user's hands (or markers 501), it is possible to acquire the user's contact points on the robot arm 251. FIG.

Also, in the first to eighth embodiments, the robot arm 251 is a multi-joint robot arm having a plurality of joints, but the number of joints is not limited to this. Although a vertical multi-axis configuration is shown as the type of robot arm, the configuration equivalent to the above can also be implemented for different types of joints such as horizontal multi-joint type, parallel link type, and orthogonal robot. Also, instead of the robot arm 251, it is possible to apply a machine that can automatically perform expansion, contraction, bending, vertical movement, horizontal movement, turning, or a combination of these operations based on the information in the storage device provided in the control device. is.

The present disclosure provides a program that implements one or more functions of the above-described embodiments to a system or device via a network or storage medium, and one or more processors in a computer of the system or device reads and executes the program. It can also be realized by processing to It can also be implemented by a circuit (for example, ASIC) that implements one or more functions.

Further, the disclosure of this specification includes the following configurations and methods.
(Configuration 1)
A robot having a contact detection unit that outputs a signal according to contact from a user, and a control unit,
The control unit controls the resistance when the user moves the robot according to the number of contact points from the user, based on the signal from the contact detection unit.
A robot device characterized by:
(Configuration 2)
The control unit controls resistance when the user changes the posture of the robot based on the number.
The robot apparatus according to configuration 1, characterized by:
(Composition 3)
The control unit
When it is determined that the contact points are not plural, controlling the resistance to be the first resistance,
When it is determined that the contact points are plural, the resistance is controlled to be a second resistance different from the first resistance,
The robot device according to configuration 1 or 2, characterized by:
(Composition 4)
The control unit controls the second resistance to be greater than the first resistance.
The robot apparatus according to configuration 3, characterized by:
(Composition 5)
The robot includes a plurality of joints and a plurality of position detection units that output signals according to the positions of the joints,
The control unit
a direct teaching mode in which a trajectory of the robot is acquired and stored by signals from the plurality of position detection units when the robot is moved by the user, and
controlling the resistance when the user moves the robot during execution of the direct teaching mode;
The robot apparatus according to any one of configurations 1 to 4, characterized by:
(Composition 6)
The contact detection unit has a contact sensor that is arranged corresponding to each link of the robot and outputs a signal when the user touches the link.
The robot apparatus according to any one of configurations 1 to 5, characterized by:
(Composition 7)
The contact detection unit has an external force detection sensor that is arranged corresponding to each link of the robot and outputs a signal due to an external force acting on the link.
The robot apparatus according to any one of configurations 1 to 6, characterized by:
(Composition 8)
Based on the signal from the external force detection sensor, the control unit generates a hand-side external force acting on a hand-side link of the robot, a base-side external force acting on a link closer to the base end than the hand-side link, and is detected, the resistance of the joint on the proximal side of the link that detects the proximal side external force is controlled to be greater than the resistance of the joint on the distal side of the link that detects the proximal side external force. do,
The robot apparatus according to configuration 7, characterized by:
(Composition 9)
When the proximal-side external force is an external force in the direction of supporting the robot's own weight, the resistance of a joint closer to the proximal side than the link that detected the proximal-side external force is greater than that of the link that detected the proximal-side external force. is greater than the resistance of the joint on the hand side,
The robot apparatus according to configuration 8, characterized by:
(Configuration 10)
The control unit switches from the second resistance to the first resistance after the lapse of a predetermined time when the contact locations change from a plurality of states to a non-plural state,
The robot apparatus according to configuration 3, characterized by:
(Composition 11)
The contact detection unit is arranged at two or more locations on each link of the robot,
The control unit controls the robot when there is a plurality of contacts from the user detected by signals from contact detection units arranged at two or more locations on one of the links of the robot. controlling a plurality of links among each of the links so that the resistance is greater than when the user is in contact;
The robot apparatus according to any one of configurations 1 to 10, characterized by:
(Composition 12)
The robot has a connection section to which an end effector can be attached to the tip of a link on the hand side, and an end effector contact detection section that outputs a signal when the user touches the end effector,
When the control unit detects the user's contact with the end effector based on the signal from the end effector contact detection unit, the resistance when moving the end effector is greater than when there are a plurality of contact points. control to be
The robot apparatus according to any one of configurations 1 to 11, characterized by:
(Composition 13)
Each link of the robot is provided with a handle that can be used when the user moves the robot,
The contact detection unit is provided for each of the handles,
The robot apparatus according to any one of configurations 1 to 10, characterized by:
(Composition 14)
Two or more handles are provided for each link of the robot,
The robot apparatus according to configuration 13, characterized by:
(Composition 15)
The robot includes at least one of an indicator or an indicator for allowing the user to use the handle.
The robot apparatus according to configuration 13 or 14, characterized by:
(Composition 16)
An operation terminal for outputting commands to the robot by a user,
When the enable switch of the operation terminal is input and it is determined that the contact point is not plural, the control unit controls the resistance to be a third resistance that is smaller than the first resistance.
The robot apparatus according to configuration 3, characterized by:
(Composition 17)
an operation terminal for outputting a command to the robot by the user;
a distance sensor that acquires the distance between the operation terminal and the robot,
The control unit
When it is determined that the distance is within a predetermined threshold and the number of contact points is not plural, the resistance is controlled to be a third resistance smaller than the first resistance,
When it is determined that the distance is out of a predetermined threshold and the number of contact points is plural, controlling to the second resistance,
When it is determined that the distance is out of a predetermined threshold and the number of contact points is not plural, the first resistance is controlled.
The robot apparatus according to configuration 3, characterized by:
(Composition 18)
comprising a user interface for obtaining identification information of the user;
The control unit controls the first resistor corresponding to the identification information and the second resistor corresponding to the identification information,
The robot apparatus according to configuration 3, characterized by:
(Composition 19)
The control unit changes resistance when starting movement of the robot according to the number of contact points.
19. The robot apparatus according to any one of configurations 1 to 18, characterized by:
(Configuration 20)
a robot having a contact detection unit that outputs a signal in response to contact from a user and an end effector contact detection unit that outputs a signal in response to contact of an object with the end effector; and a control unit,
When the control unit detects contact of an object with the end effector from the signal from the end effector contact detection unit, the user's contact with any of the links of the robot is detected from the signal from the contact detection unit. control so that the resistance when moving the posture of the end effector is greater than in the case of
A robot device characterized by:
(Composition 21)
The robot has a plurality of drive sources,
The control unit controls the resistance using the plurality of drive sources.
21. The robot apparatus according to any one of configurations 1 to 20, characterized by:
(Method 22)
a robot having a contact detection unit that outputs a signal in response to contact from a user;
In a control method for a robot device comprising a control unit,
The control unit controls the resistance when the user moves the robot according to the number of contact points from the user, based on the signal from the contact detection unit.
A control method characterized by:
(Composition 23)
A program for causing a computer to perform the control method described in Method 22.
(Composition 24)
A computer-readable recording medium in which the program according to configuration 23 is recorded.
(Method 25)
a robot having a contact detection unit that outputs a signal in response to contact from a user;
In a teaching method for a robot device comprising a control unit,
The control unit controls the resistance when the user moves the robot according to the number of contact points from the user, based on the signal from the contact detection unit, while controlling the movement of the robot by the user. obtaining a trajectory of the robot based on
A teaching method characterized by:
(Method 26)
An article manufacturing method comprising operating a robot device comprising a robot having a contact detection unit that outputs a signal in response to contact from a user and a control unit to manufacture an article by the robot device,
The control unit controls the resistance when the user moves the robot according to the number of contact points from the user, based on the signal from the contact detection unit, while controlling the movement of the robot by the user. obtaining the trajectory of the robot based on
Operating the robot based on the trajectory to manufacture the article;
A method for manufacturing an article characterized by:

10... 1st link (link) / 11... 2nd link (link) / 12... 3rd link (link) / 13... 4th link (link) / 14... 5th link (link) / 15... 6th link (Link) / 16 ... Tip flange (connection part) / 100 ... Robot device / 211 ... Electric motor (driving source) / 212 ... Electric motor (driving source) / 213 ... Electric motor (driving source) / 214 ... Electric motor ( Drive source) / 215 Electric motor (drive source) / 216 Electric motor (drive source) / 251 Robot arm / 252 Hand tool (end effector) / 300 Control device (control unit) / 541 Torque sensor ( Contact detection unit, external force detection sensor) / 542 Torque sensor (contact detection unit, external force detection sensor) / 543 Torque sensor (contact detection unit, external force detection sensor) / 544 Torque sensor (contact detection unit, external force detection sensor) /545...Torque sensor (contact detection section, external force detection sensor)/546...Torque sensor (contact detection section, external force detection sensor)/551...Position sensor (position detection section)/552...Position sensor (position detection section)/553 Position sensor (position detection unit)/554 Position sensor (position detection unit)/555 Position sensor (position detection unit)/556 Position sensor (position detection unit)/710 Contact sensor (contact detection unit)/711 Contact sensor (contact detection unit)/712 Contact sensor (contact detection unit)/713 Contact sensor (contact detection unit)/714 Contact sensor (contact detection unit)/715 Contact sensor (contact detection unit)/716 ... Contact sensor (contact detection unit) / J ₁ ... Joint / J ₂ ... Joint / J ₃ ... Joint / J ₄ ... Joint / J ₅ ... Joint / J ₆ ... Joint

Claims (26)

A robot having a contact detection unit that outputs a signal according to contact from a user, and a control unit,
The control unit controls the resistance when the user moves the robot according to the number of contact points from the user, based on the signal from the contact detection unit.
A robot device characterized by: The control unit controls resistance when the user changes the posture of the robot based on the number.
2. The robot apparatus according to claim 1, wherein: The control unit
When it is determined that the contact points are not plural, controlling the resistance to be the first resistance,
When it is determined that the contact points are plural, the resistance is controlled to be a second resistance different from the first resistance,
2. The robot apparatus according to claim 1, wherein: The control unit controls the second resistance to be greater than the first resistance.
4. The robot apparatus according to claim 3, characterized in that: The robot includes a plurality of joints and a plurality of position detection units that output signals according to the positions of the joints,
The control unit
a direct teaching mode in which a trajectory of the robot is acquired and stored by signals from the plurality of position detection units when the robot is moved by the user, and
controlling the resistance when the user moves the robot during execution of the direct teaching mode;
2. The robot apparatus according to claim 1, wherein: The contact detection unit has a contact sensor that is arranged corresponding to each link of the robot and outputs a signal when the user touches the link.
2. The robot apparatus according to claim 1, wherein: The contact detection unit has an external force detection sensor that is arranged corresponding to each link of the robot and outputs a signal due to an external force acting on the link.
2. The robot apparatus according to claim 1, wherein: Based on the signal from the external force detection sensor, the control unit generates a hand-side external force acting on a hand-side link of the robot, a base-side external force acting on a link closer to the base end than the hand-side link, and is detected, the resistance of the joint on the proximal side of the link that detects the proximal side external force is controlled to be greater than the resistance of the joint on the distal side of the link that detects the proximal side external force. do,
8. The robot apparatus according to claim 7, characterized in that: When the proximal-side external force is an external force in the direction of supporting the robot's own weight, the resistance of a joint closer to the proximal side than the link that detected the proximal-side external force is greater than that of the link that detected the proximal-side external force. is greater than the resistance of the joint on the hand side,
9. The robot apparatus according to claim 8, characterized by: The control unit switches from the second resistance to the first resistance after the lapse of a predetermined time when the contact locations change from a plurality of states to a non-plural state,
4. The robot apparatus according to claim 3, characterized in that: The contact detection unit is arranged at two or more locations on each link of the robot,
The control unit controls the robot when there is a plurality of contacts from the user detected by signals from contact detection units arranged at two or more locations on one of the links of the robot. controlling a plurality of links among each of the links so that the resistance is greater than when the user is in contact;
2. The robot apparatus according to claim 1, wherein: The robot has a connection section to which an end effector can be attached to the tip of a link on the hand side, and an end effector contact detection section that outputs a signal when the user touches the end effector,
When the control unit detects the user's contact with the end effector based on the signal from the end effector contact detection unit, the resistance when moving the end effector is greater than when there are a plurality of contact points. control to be
2. The robot apparatus according to claim 1, wherein: Each link of the robot is provided with a handle that can be used when the user moves the robot,
The contact detection unit is provided for each of the handles,
2. The robot apparatus according to claim 1, wherein: Two or more handles are provided for each link of the robot,
14. The robot apparatus according to claim 13, characterized by: The robot includes at least one of an indicator or an indicator for allowing the user to use the handle.
14. The robot apparatus according to claim 13, characterized by: An operation terminal for outputting commands to the robot by a user,
When the enable switch of the operation terminal is input and it is determined that the contact point is not plural, the control unit controls the resistance to be a third resistance that is smaller than the first resistance.
4. The robot apparatus according to claim 3, characterized in that: an operation terminal for outputting a command to the robot by the user;
a distance sensor that acquires the distance between the operation terminal and the robot,
The control unit
When it is determined that the distance is within a predetermined threshold and the number of contact points is not plural, the resistance is controlled to be a third resistance smaller than the first resistance,
When it is determined that the distance is out of a predetermined threshold and the number of contact points is plural, controlling to the second resistance,
When it is determined that the distance is out of a predetermined threshold and the number of contact points is not plural, the first resistance is controlled.
4. The robot apparatus according to claim 3, characterized in that: comprising a user interface for obtaining identification information of the user;
The control unit controls the first resistor corresponding to the identification information and the second resistor corresponding to the identification information,
4. The robot apparatus according to claim 3, characterized in that: The control unit changes resistance when starting movement of the robot according to the number of contact points.
2. The robot apparatus according to claim 1, wherein: a robot having a contact detection unit that outputs a signal in response to contact from a user and an end effector contact detection unit that outputs a signal in response to contact of an object with the end effector; and a control unit,
When the control unit detects contact of an object with the end effector from the signal from the end effector contact detection unit, the user's contact with any of the links of the robot is detected from the signal from the contact detection unit. control so that the resistance when moving the posture of the end effector is greater than in the case of
A robot device characterized by: The robot has a plurality of drive sources,
The control unit controls the resistance using the plurality of drive sources.
21. The robot apparatus according to any one of claims 1 to 20, characterized in that: a robot having a contact detection unit that outputs a signal in response to contact from a user;
In a control method for a robot device comprising a control unit,
The control unit controls the resistance when the user moves the robot according to the number of contact points from the user, based on the signal from the contact detection unit.
A control method characterized by: A program for causing a computer to execute the control method according to claim 22. A computer-readable recording medium on which the program according to claim 23 is recorded. a robot having a contact detection unit that outputs a signal in response to contact from a user;
In a teaching method for a robot device comprising a control unit,
The control unit controls the resistance when the user moves the robot according to the number of contact points from the user, based on the signal from the contact detection unit, while controlling the movement of the robot by the user. obtaining a trajectory of the robot based on
A teaching method characterized by: An article manufacturing method comprising operating a robot device comprising a robot having a contact detection unit that outputs a signal in response to contact from a user and a control unit to manufacture an article by the robot device,
The control unit controls the resistance when the user moves the robot according to the number of contact points from the user, based on the signal from the contact detection unit, while controlling the movement of the robot by the user. obtaining the trajectory of the robot based on
Operating the robot based on the trajectory to manufacture the article;
A method for manufacturing an article characterized by:

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