Characterisation of microano CMM probes

摘要

Microano CMM probes need to be characterised thoroughly for design optimisation and signal interpretation. Calibrations of spring constants of microano CMM probes in all three probing directions using reference springs are introduced. A new cantilever cube is presented which includes three cantilevers acting as reference springs, whose spring constants are calibrated using a high accurate weight balance. Stiffnesses of a piezoresistive probe and an assembled cantilever ball probe are investigated. For instance, the piezoresistive probe has spring constants of 208.8 N/m, 313.8 N/m and 5642.9 N/m in the x, y, and z probing directions, respectively. In addition, a method for estimating the adhesive forces between probing sphere and sample is introduced. Experimental results show an adhesive force of 2.06 μN for a sapphire probing sphere with a diameter of 120 μm on a sapphire sample surface.