Self-calibration can be a desirable feature for an intelligent machine such as a computer controlled numerical machine tool that must function outside of controlled laboratory conditions. This is because it is inevitable that variations in the kinematic model arise from imperfections in the manufacturing process and changes of environment conditions. Self-calibration facilitates online compensation of errors induced by loading, thermal and other nongeometric errors.
This paper focuses the determination of the maximum number of independent kinematic parameters of a parallel-link mechanism for system self-calibration. Under the assumption of ideal joints and links, a method for obtaining this number is given. A number of examples is given to illustrate the applicability of the proposed method. The result can also be extended to tackle conventional calibration tasks.