# Part-based Hand-eye Calibration

Part-based hand-eye calibration involves using a part that is used during run-time as a calibration target. Part-based hand-eye calibration has the following advantages:

- A special fixture to hold the calibration target is not necessary. This is because the alignment system is designed to hold the part
- Special lighting is not necessary to illuminate the part. The illumination that is used during run-time can be used during calibration.

The disadvantages to using a part for hand-eye calibration are as follows:

- Unlike the checkerboard-based hand-eye calibration, the user will have to add feature finders to locate the features that are used to compute the calibration results
- On systems where lens and perspective distortion must be computed, the calibration target would have to be moved to a lot of positions to generate a dense set of features
- The quality of the hand-eye calibration result and hence alignment is adversely affected by scaling errors in their linear degrees of freedom

The following figure illustrates this with a single camera.