Tool center point calibration device and method

A method of tool center point calibration, the method comprising the following steps:

• a) providing
• a first light beam and a second light beam at an angle to the first light beam,
• wherein an axis of the first light beam and an axis of the second light beam intersect at a reference intersection point;
• a first light detector configured to receive the first light beam and to generate a first signal when the first light beam is interrupted;
• a second light detector configured to receive the second light beam and to generate a second signal when the second light beam is interrupted;
• b) initiating a movement of a tool, which includes at least one of a cutting tool, a welding tool, a robot gripper, and a dispenser tool, along a straight first path section, wherein the tool comprises a tool tip;
• c) receiving the first signal when the tool tip crosses the first light beam at a first crossing point and storing the coordinates of the first crossing point,
• d) receiving a second signal when the tool tip crosses the second light beam at a second crossing point and storing the coordinates of the second crossing point,
• e) changing a direction of the movement of the tool to move the tool along a straight second path section;
• f) receiving the first signal when the tool tip crosses the first light beam at a third crossing point and storing the coordinates of the third crossing point with the controller,
• g) calculating coordinates of a virtual intersection point based on coordinates of the first crossing point, the coordinates of the second crossing point, and the coordinates of the third crossing point.

A tool center point calibration device comprising a substantially U-shaped body, the body holding:

• at least one light source configured to generate a first light beam and a second light beam at an angle to the first light beam, an axis of the first light beam and an axis of the second light beam intersect at a reference intersection point;
• a first light detector configured to receive the first light beam and to generate a first signal when the first light beam is interrupted;
• and
• a second light detector configured to receive the second light beam and to generate a second signal when the second light beam is interrupted,
• wherein the first light beam does not intersect the second light beam.