To meet the requirement of high precision measurement of coordinate measurement machine system, a compact microprobe has been designed for 3D measurement in this paper. Aiming to reduce the influences of signal coupling during the probing process, the probe has been designed by adopting two elastic mechanisms, in which the horizontal and vertical motions of the probe tip can be separated by differential signals of quadrant photodetectors in each elastic mechanism. A connecting rod has been designed to transfer the displacement of the probe tip in vertical direction from lower to upper elastic mechanisms. The sensitivity models in horizontal and vertical directions have been established, and the sensor sensitivity has been verified through experiments. Furthermore, the signal coupling of three axes has been analyzed, and mathematical models have been proposed for decoupling. The probing performance has been verified experimentally.
Patterned leaf springs made of a beryllium bronze sheet are the key components of certain micro/nano contact probes. The accuracy of the probe is determined based on the precision of the formed pattern. However, a traditional manufacturing method using wire-electrode discharge machining (wire-EDM) is subject to poor tolerance at the sharp edges and corners. In addition, high energy consumption and costs are incurred for complex patterns. This paper presents a new chemical etching method for the manufacturing of a patterned leaf spring with high precision. Both the principle and process are introduced. Taguchi experiments were designed and conducted and the optimal process parameters were obtained based on the mean value and a variance analysis. Four V-shaped and some other complex patterned leaf springs were successfully fabricated. Comparison experiments concerning the characteristic parameters of the leaf spring were also conducted. The experimental results reveal that the patterned leaf springs manufactured through this method are much better than those achieved using wire-EDM. This manufacturing method can be used to fabricate different high-precision patterned leaf springs or membranes for coordinate measuring machines (CMM) probes and other measuring equipment.