Problem Analysis of Conoprobe in Gear Measurement Application

Conoprobe is used for non-contact measurement utilizing conoscopic holography technology, which has characteristics of high measurement precision and large measuring angle range. However, the conoprobe performs inaccurate and instable in gear measurement applications. To verify its accuracy, an experiment setup is built using high performance coordinate measuring machine (CMM) to measure surfaces of gaugeblocks that have similar material as gear workpieces. Compared the collected data from the CMM with the conoprobe values, those problems mentioned above are validated. In this study it can be stated that measuring accuracy of conoprobe drops dramatically when measuring bright metal surfaces, and even its measuring error could be more than dozens of microns when the measurement is in large angle, therefore it is completely not fit for precision measurement applications.