Robot system

Abstract

Increased security of robot operation, efficient use of the floor space in a factory or the like, and simplified facilities are achieved. A process includes defining, in a memory, arm-occupied regions including robot arms and a workpiece and a tool attached to a robot wrist, a virtual safety protection barrier with which the arms are not allowed to come into contact, and a movable range of each robot axis; estimating the coasting angle of each robot axis for which the axis will coast when the robot is stopped due to an emergency stop during execution of a command for moving the robot to a next target position, from an actually measured amount of coasting and the like; determining a post-coasting predicted position of the robot by adding the coasting angles of the axes to the next target position; checking whether or not the arm-occupied regions at the post-coasting predicted position will come into contact with the virtual safety protection barrier, or whether or not the robot axes are within the movable ranges; and performing control to cause the robot to stop moving immediately upon detection of abnormality.

Description

technical field [0001] The invention relates to a robot system that limits the range of motion of a robot. Background technique [0002] As an existing robot system, as shown in Japanese Patent Publication No. 2004-322244, the area used to limit the movement of the robot is defined as a "virtual safety barrier" on the memory, and at least two places including workpieces and tools are defined. In a part of the three-dimensional space area, the predicted position in the trajectory calculation of the three-dimensional space area is searched for the virtual safety barrier, and even if only a part of the three-dimensional space area touches the virtual safety barrier, the robot is controlled to stop. [0003] However, in the prior art, the robot is stopped when the predicted position on the trajectory calculation exceeds the virtual safety barrier, because even if the robot stops due to an emergency stop or the like when the predicted position on the trajectory calculation is not...

AI Technical Summary

Problems solved by technology

[0003] However, in the prior art, the robot is stopped when the predicted position on the trajectory calculation exceeds the virtual safety barrier, because even if the robot stops due to an emergency stop or the like when the predicted position on the trajectory calculation is not exceeded, the robot There will also be a lot of inertial movement, so the position where the robot actually stops is different from the position on the trajectory calculation

Therefore, there is the following problem, even if the trajectory calculation does not exceed the virtual safety barrier, the robot will exceed the virtual safety barrier

[0004] In addition, the range limit of each axis of the existing robot is to limit the command value and the current motor position, and the robot will exceed the limit range due to emergency stop, etc.

Therefore, there is a problem that the equipment cost is increased by realizing range limitation by a mechanical device such as a mechanical limiter.

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