Panasonic Intellectual Property Management Co., Ltd.

Hiroyoshi Ueda

Atsumi Hashimoto

Hiroyuki Nakata

Ryosuke Yamamoto

Masayoshi Iwatani

Yasuyoshi Honuchi

When workpiece (W) is brought into a non-gripping state after deflection compensation of robot arm () is performed in a gripping state of workpiece (W), the deflection compensation of robot arm () is performed in a non-gripping state of workpiece (W). Here, the deflection compensation of robot arm () in the non-gripping state of workpiece (W) is performed while a compensation amount is changed to gradually decrease, while hand () is moved from a first teaching point to a second teaching point.

Robot control method

Stop and start detection block () determines whether or not a joint portion is in a stopped state before a rotation direction of the joint portion is inverted based on stop flag signal (Stop_Flg). When it is determined that the joint portion is in the stopped state, filter processing block () changes a frequency component of a correction amount for correcting backlash to a low frequency lower than a predetermined threshold value.

Robot control method and robot control device

A determination value calculated based on a distance from a work point of a tip of robot arm () to virtual straight line () passing through an axis of second joint (J) and an axis of third joint (J) is compared with a predetermined threshold. A method of calculating deflection compensation amounts for second joint (J) and third joint (J) is changed depending on whether the determination value is larger or smaller than the threshold. Second joint (J) and third joint (J) are caused to pivot based on the calculated deflection compensation amounts.

Load information on a tool to be attached to a robot arm and collision sensitivity are input. Gravitational torque is calculated based on the input load information. A deflection amount of the robot arm is calculated based on the gravitational torque. A correction amount is calculated based on the collision sensitivity input. The deflection amount is corrected while the robot arm moves.

In an angular velocity calculation block, an angular velocity component is calculated based on a position command for a joint portion. In a kinetic calculation block, a kinetic torque is calculated based on the position command for the joint portion. In a command velocity component reversal detection block, a reversal timing is calculated based on the angular velocity component. In a reverse torque detection block, a reverse torque is calculated based on the kinetic torque and the reversal timing. In a backlash correction amount calculation block, the correction amount of the joint portion is calculated based on the kinetic torque, the reverse torque, and the reversal timing.

A robot control device includes the following: a main control unit; a servo control unit, which receives a position command &#x3b8;c from the main control unit; and a bending correction block (), which corrects the bending of the reduction gear connected to the servo motor. The bending correction block () includes the following: a first position-correction-value calculation means (), which finds a first position-command correction value &#x3b8;sgc based on the position command &#x3b8;c; and a second position-command-correction-value calculation means (), which finds a second position-command correction value &#x3b8;skc based on the interference torque &#x3c4;a. The servo control unit drives the servo motor based on a new position command obtained by adding the first position-command correction value &#x3b8;sgc and the second position-command correction value &#x3b8;skc to the position command &#x3b8;c.

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Osaka, Japan

Hiroyoshi Ueda