Dynamic analysis of mechanical model for three-dimensional resonant trigger probe and experiment

A novel three-dimensional resonant trigger probe, which is fabricated with force sensitive components with good resonant characteristics and an integrated micro-stem and microsphere, is a new type of probe for micro/nano coordinating measuring machine (micro/nano CMM). In this paper, its triggering mechanical models are proposed to simulate the nano interaction between sample surface and the microsphere tip of the probe. In the models, the interaction between the sample surface and microsphere tip in Z direction is presumed in tapping mode (TM) and the interactions in X and Y directions are presumed in friction mode (FM). Taking account of air damping, energy dissipation, restoring force of elastic deformation, nanoscale interface friction, interface adhesion and van der Waals force, the models of the interactions between the microsphere tip and the sample surface in X(Y) direction and Z direction are deduced and constructed respectively. Based on the proposed models, the dynamic analysis on the triggering mechanism of the probe is presented. By experiment, the three-dimensional approaching curves of the probe are observed and they are proven to be suitable for the triggering signals of the probe. Preliminary experimental results show that the trigger resolution of the probe is about 0.24 nm in X direction, 0.20 nm in Y direction and 0.18 nm in Z direction. The theoretical analysis and experimental results demonstrate the validity of the novel resonant trigger probe.