Functional Methods are used to determine joint parameters based on isolated joint movements. The subject has to execute joint specific movement patterns in sperate calibration trials which are used to determine joint axes (defined by a point and a direction vector) and joint centres.

Different algorithms are implemented. They show differences in the needed requirements, in the values of the determined joint parameters and also in the robustness against different sources of measurement errors, e.g. skin motion artefacts. This results in the fact that the joice of the method depends on the application.