What is the tool center point and why does TCP calibration matter?
The tool center point, or TCP, is the point and orientation the controller uses to represent the working end of the tool. It might be a gripper's contact location, a welding tip, or a dispensing nozzle. The TCP differs from the bare flange position when a tool is attached.
What this means in practice
Correct TCP calibration lets the controller rotate and move the tool around its actual working point. An incorrect TCP can cause paths to shift when orientation changes, even if the robot's joints are operating consistently. Tool replacement, wear, or movement of an adapter can require recalibration.
Separate geometry from load settings
TCP calibration describes where the working point is relative to the flange. Payload configuration describes the supported mass and its distribution. These settings solve different problems, so correcting one does not automatically correct the other.
A useful verification changes tool orientation while keeping the intended working point at a reference location, using the manufacturer's approved procedure. Unexpected displacement can indicate a geometric configuration issue. Recheck after replacing a nozzle, moving an adapter, or repairing a tool, and retain the verified settings with the production program.
Key points
Define the working point for the actual task.
Follow the manufacturer's calibration procedure and verify the result.
Maintain separate tool configurations when different end effectors are used.
Practical example and next step
Verify calibration at several orientations using an appropriate reference. Record the tool configuration with the program and inspect it after changes. TCP calibration establishes tool geometry; it does not replace payload configuration, fixture calibration, or an application performance check.