Profile control system for robots
AssigneeFujitsu Limited
InventorsYasuyuki Nakata, Akihiko Yabuki, Yutaka Yoshida, Katsushi Nishimoto
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Abstract
A robot profile control system permits a force control robot to perform a profiling operation on a surface of a work object having curved surfaces of unknown contours. The robot profile control system resets a profile coordinate system for the profile operation on the basis of force acting between the end of the robot and the work object. The force is detected by a force detecting section of the robot profile control system.
Claims14
A profile control system for a force control robot system including a robot, a force detecting section for detecting a force acting between an end of the robot and a work object, and a position detecting section detecting the position of the end of the robot and permitting the robot to perform a profiling operation on a surface of the work object from a known start point to a known target point, said profile control system comprising:
- calculating means for calculating a unit vector L in a target direction at a contact point between the end of the robot and the work object, by equation ##EQU19## wherein a unit vector L.sub.i at a contact point P.sub.i in a profiling operation is calculated using a position vector P.sub.i and pt at the contact point P.sub.i and the target point P.sub.E, respectively;.
- normal vector calculating means for calculating a unit vector n at a point of contact between the end of the robot and the work object based on the force detected by the force detecting section;
- movement calculating means for calculating a unit vector o in a direction of movement of the end of the robot, comprising:
- first means for finding a unit vector a as an outer product of the unit vector n and the unit vector L in a direction of an outer product of the unit vector n and the unit vector L, and
- second means for finding the unit vector o as an outer product of the unit vector a and the unit vector n in a direction of the outer product of the unit vector a and the unit vector n;
- control command generating means for generating control commands to said robot based on the unit vector o in the direction of movement of the end of the robot and the unit vector n;
- and
- force and position control means for controlling the force of the robot and the position of the end of the robot based on at least the control commands, permitting the robot to perform a profile on a surface of the work object having the known start point, the known target point, and an unknown contour.
A profile control system for a force control robot system permitting a robot to perform a profiling operation on a surface of a work object from a known start point to a known target point, said profile control system comprising:
- target position calculating unit calculating a unit vector L in the direction of movement to the target position at a point of contact between an end of the robot and the work object at the target position;
- a force detector detecting a force between the end of the robot and the work object;
- a normal vector calculating unit coupled to the force detector for calculating a unit vector n at a point of contact between the end of the robot and the work object based on the force;
- movement calculating unit coupled to the normal vector calculating unit for calculating a vector a as an outer product of unit vectors n and L in a direction of the outer product of the unit vectors n and L, and calculating a unit vector o as an outer product of unit vectors a and n in a direction of the outer product of the unit vectors a and n;
- a control command generating unit generating control commands to the robot based on the unit vector o in a direction of movement of the end of the robot and the unit vector n;
- and
- a force and position control unit controlling a force exerted by the end of the robot on the work object, and the position of the end of the robot relative to the work object, based on at least the control commands.
Dependencies are inferred from the claim text.