JP2016168650A5

JP2016168650A5 -

Info

Publication number: JP2016168650A5
Application number: JP2015050260A
Authority: JP
Filing date: 2015-03-13
Publication date: 2018-04-19
Anticipated expiration: 2035-03-13

Claims

A robot arm having a joint;
An end effector attached to the robot arm;
A movement control mode for controlling the operation of the robot arm so that the end effector moves to a work start position for performing a predetermined work, and a force in a predetermined direction among the forces acting on the end effector during the predetermined work. A control device having a compliance control mode for controlling the operation of the robot arm so as to reduce the component, and
The joint of the robot arm includes a motor and a joint driving device having a speed reducer that decelerates the rotation of the motor, a first angle detection unit that detects a rotation angle of the motor, and a second that detects the angle of the joint. An angle detection unit,
The control device calculates torque acting on the joint using the angle detection result of the first angle detection unit and the angle detection result of the second angle detection unit, and uses the calculation result of the torque of the joint. A robot apparatus that calculates a force acting on the end effector.

In the compliance control mode, the control device includes a force component in the predetermined direction out of the force calculated before starting the predetermined work and a force component in the predetermined direction out of the forces calculated during the predetermined work. The robot apparatus according to claim 1, wherein the operation of the robot arm is controlled so as to reduce a difference from the robot arm.

The control device includes a difference between a result of converting the angle detection result of the first angle detection unit into an angle of the joint with a reduction gear ratio of the reduction gear set in advance and an angle detection result of the second angle detection unit. 3. The robot apparatus according to claim 1, wherein a torque acting on the joint is calculated from a torsional rigidity of the speed reducer set in advance. 4.

The said control apparatus calculates the force which acts on the said end effector from the calculation result of the torque of the said joint, and the preset link parameter of the said robot arm, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. The robot apparatus as described in.

The end effector is a robot hand having a plurality of fingers,
The predetermined work is a fitting work for fitting a work gripped by the robot hand to another work, or an extraction work for extracting the work gripped by the robot hand from another work. Item 5. The robot apparatus according to any one of Items 1 to 4.

The robot arm includes a plurality of the joints including the joint driving device, the first angle detection unit, and the second angle detection unit,
The said control apparatus calculates the torque which each acts on these joints, and calculates the force which acts on the said end effector using the calculation result of these torques, The any one of Claim 1 thru | or 5 characterized by the above-mentioned. The robot apparatus according to item 1.

The controller is
A plurality of joint control units for supplying a current to the motor to control a joint angle of the robot arm so that a rotational position of the motor approaches an input position command;
The robot apparatus according to claim 6, further comprising: a main control unit that outputs a position command to each joint control unit.

Each joint control unit calculates a torque acting on each joint, and outputs a torque calculation result to the main control unit,
The main control unit generates a position command based on a preset teaching point,
In the movement control mode, a position command based on the teaching point is output to each joint control unit,
In the compliance control mode, a force acting on the end effector is calculated using a calculation result of torque received from each joint control unit, and a force component in the predetermined direction is reduced among the calculated forces. The robot apparatus according to claim 7, wherein the position command based on the teaching point is corrected, and the corrected position command is output to each joint control unit.

The joint of the robot arm has a motor and a joint driving device having a speed reducer that decelerates the rotation of the motor, a first angle detection unit that detects the rotation angle of the motor, and a second angle that detects the angle of the joint A robot control method in which the control device controls the operation of the robot arm,
A movement control step in which the control device controls the robot arm so that an end effector attached to the robot arm moves to a work start position for performing a predetermined work;
A torque calculating step in which the control device calculates a torque acting on the joint using an angle detection result of the first angle detection unit and an angle detection result of the second angle detection unit;
A force calculating step in which the control device calculates a force acting on the end effector using a calculation result of the torque of the joint;
A compliance control step for controlling the operation of the robot arm so that a force component in a predetermined direction out of the force acting on the end effector is reduced during the predetermined work. A robot control method characterized by the above.

In the compliance control step, the control device includes a force component in the predetermined direction out of the force calculated before starting the predetermined operation, and a force component in the predetermined direction out of the force calculated during the predetermined operation. The robot control method according to claim 9, wherein the operation of the robot arm is controlled so as to reduce a difference between the robot arm and the robot arm.

In the torque calculation step, the control device converts the angle detection result of the first angle detection unit into the angle of the joint by a preset reduction gear ratio, and the second angle detection unit. The robot control method according to claim 9 or 10, wherein a torque acting on the joint is calculated from a difference from an angle detection result and a torsional rigidity of the reduction gear set in advance.

10. The force calculating step, wherein the control device calculates a force acting on the end effector from a calculation result of the joint torque and a preset link parameter of the robot arm. 12. The robot control method according to any one of 11 above.

The robot arm includes a plurality of the joints including the joint driving device, the first angle detection unit, and the second angle detection unit,
In the torque calculation step, the control device calculates torques acting on the plurality of joints,
The said control apparatus calculates the force which acts on the said end effector using the calculation result of the several torque calculated in the said torque calculation process at the said force calculation process. The robot control method according to any one of claims.

The program for making a computer perform each process of the robot control method of any one of Claim 9 thru | or 13.

The computer-readable recording medium which recorded the program of Claim 14.

14. A method for manufacturing an article, wherein the robot arm is controlled by the robot control method according to claim 9, and the article is manufactured by assembling the first workpiece to the second workpiece.