Patent ID: 8423189

Claim:
A robot system comprising: a robot arm driven by a motor; a collision detector that detects a collision between the robot arm and an obstacle; and a stopping method selector that controls the robot arm by selecting a stopping method from among a plurality of stopping methods on the basis of the information obtained by the collision detector, wherein the stopping method selector selects the stopping method on the basis of the information obtained by the collision detector and information indicating at which joint axis of the robot arm the collision is detected, wherein, when the joint axis for which the collision is detected is a fundamental axis, the stopping method selector causes all parts of the robot arm moving around respective axes to be pulled back upon detection of the collision, and wherein, when the joint axis for which the collision is detected is a wrist axis, the stopping method selector is configured to cause: a part of the robot arm moving around the wrist axis to be stopped by flexible stopping processing and a second part of the robot arm moving around the fundamental axis to be stopped by immediate stopping processing upon detection of the collision, or all parts of the robot arm moving around respective axes to be pulled back upon detection of the collision.