Integration of a piezoresistive microprobe into a commercial gear measuring instrument
Various microprobes have been developed in the last decade to address the needs of micrometrology. However, most microprobes are only employed in specialized measuring machines located in a few research institutes and are not widespread in the industry. This work aims to extend the capabilities of conventional coordinate measuring machines (CMMs) towards measuring microgeometries through the low-cost integration of a tactile microprobe. In order to demonstrate this, a gear measuring instrument (GMI), which is a commercial CMM not specialized for measurements at the microscale, has been equipped with a recently developed silicon-membrane-based microprobe. In the first part of this work, the working principle of the microprobe, its assembly and its integration into the GMI are described. Two different mounting setups of the microprobe onto the GMI were evaluated and tested. Measurements on the GMI were performed solely with the microprobe or by combining the microprobe and the measurement system already present on the GMI. This combination makes it possible to use the microprobe advantageously and to exchange it in a comfortable semi-automatic way. To test these two mounting setups, a new involute scanning artifact (SAFT) with superimposed waviness was measured.