Kinematic analysis and optimal design of a 3D compliant probe

The difference of the probe´s stiffness in the different measuring direction and its dynamic characteristics will influence the measuring precision of a coordinate measuring machine (CMM), so the consistency of directional compliance of the probe is demanded. In this paper, we introduce a 3D probe used in a CMM, which takes advantage of delta structure and flexure hinges. The freedom of the 3D compliant probe is analyzed in screw theory, and its kinematic analysis is done in the matrix method. After simulation and experiments on the probe, the output to input displacement transforming matrix is built up and the finite element model of the probe is verified by modal test and the finite element analysis (FEA). Finally, the optimization of key dimensions is implemented based on the verified finite element model, the optimized model of the 3D compliant probe is obtained.