US 12,290,942 B2
Method for controlling robot, robot system, and storage medium
Shunsuke Toshimitsu, Azumino (JP)
Assigned to SEIKO EPSON CORPORATION, (JP)
Filed by Seiko Epson Corporation, Tokyo (JP)
Filed on Mar. 30, 2022, as Appl. No. 17/708,335.
Claims priority of application No. 2021-062362 (JP), filed on Mar. 31, 2021.
Prior Publication US 2022/0314451 A1, Oct. 6, 2022
This patent is subject to a terminal disclaimer.
Int. Cl. B25J 9/16 (2006.01); B25J 9/04 (2006.01); B25J 9/12 (2006.01)
CPC B25J 9/1692 (2013.01) 8 Claims
OG exemplary drawing
 
1. A method for controlling a robot including a base, a robot arm coupled to the base, and a drive unit including a motor for driving the robot arm, the method comprising:
a first step of acquiring height information on a height of a tip end of the robot arm at a lowering operation start position from which the tip end of the robot arm is lowered;
a second step of determining a frequency component to be removed from a drive signal for driving the motor based on the height information acquired in the first step; and
a third step of removing the frequency component determined in the second step from the drive signal to generate a correction drive signal,
wherein an end effector is attached to the robot arm,
the tip end of the robot arm is a control point on the end effector,
the robot arm is configured to execute a lifting operation in which the tip end of the robot arm is lifted from an operation start position and a lowering operation in which the tip end of the robot arm is lowered from the lowering operation start position after the lifting operation,
the determination of the frequency component in the second step is performed based on a height of the tip end of the robot arm at a position which is obtained by selecting one of the operation start position and the lowering operation start position,
in the second step, when at least one of the following conditions 1, 2, and 3 is satisfied, the frequency component is determined based on the height of the tip end of the robot arm at the lowering operation start position, and when none of the following conditions 1, 2, and 3 is satisfied, the frequency component is determined based on the height of the tip end of the robot arm at the operation start position,
condition 1: a distance between the lowering operation start position and a lowering operation end position at which the lowering operation is ended is equal to or greater than a predetermined distance,
condition 2: a height of the lowering operation start position is equal to or higher than a predetermined height, and
condition 3: the height of the lowering operation end position is equal to or higher than the predetermined height.