초록 ▼

A robot calibration system includes a calibration sensor that provides an indication of when a first reference point that remains fixed relative to a robot base is a fixed distance from a second reference point that is located on the robot arm. The robot arm is moved through a plurality of orientati

A robot calibration system includes a calibration sensor that provides an indication of when a first reference point that remains fixed relative to a robot base is a fixed distance from a second reference point that is located on the robot arm. The robot arm is moved through a plurality of orientations and each time that the fixed distance between the two reference points is achieved, robot joint position information is determined. The preferred calibration sensor includes a string that extends between the two reference points and activates a signal generator each time that the string is taut as caused by the orientation of the robot arm. The generated signal indicates that the two reference points are separated by the fixed distance. The determined robot joint positions are then used to determine a calibration factor which varies depending on the needs of a particular situation. Example calibration factors are useful for correcting errors in robot kinematic information, locating the workcell reference frame and locating the tool center point reference frame.

대표청구항 ▼

[ We claim:] [1.] A method of calibrating a robot system having a robot arm that is supported on a base and includes a plurality of joints that have a set of default positions and are moveable into a plurality of joint positions to provide a plurality of robot arm orientations, comprising the steps

[ We claim:] [1.] A method of calibrating a robot system having a robot arm that is supported on a base and includes a plurality of joints that have a set of default positions and are moveable into a plurality of joint positions to provide a plurality of robot arm orientations, comprising the steps of:(A) establishing a first reference location that remains fixed relative to the robot base;(B) establishing a second reference location on the robot arm;(C) automatically moving the robot arm into a plurality of orientations where at least one of the joints is in a position that is different from the position of the one joint in a previous orientation;(D) determining when the second reference location is at least one fixed distance from the first reference location;(E) determining each joint position associated with each orientation where the second reference location is the fixed distance from the first reference location; and(F) determining a calibration factor by comparing the default positions with the joint positions from step (E).