Precision Assessment of Tactile On-Machine Inspection for Milling Operations

The manufacturing industry faces customer demands for increased product quality and individuality to be economically successful. Established processes on the shop floor cannot overcome resulting challenges. Due to the increased quality requirements, potentially more products must be checked regarding their requirement fulfilment. In addition, customer individuality increases the number and rate of product releases. During product releases, the quality of the product is checked. Coordinate measuring machines are usually used for the quality assessment of milling processes. However, these are only suitable in the area of high quantities per batch due to downtimes of the milling machine while assessing product quality. On-machine inspection systems show particular strengths when a high proportion of the manufactured products have to be inspected and potentially reworked. These systems are criticized for their poor accuracy compared to coordinate measuring machines. This paper demonstrates the accuracy and repeatability of a tactile system in a field test at a tool manufacturer. Based on the test results, the tactile on-machine inspection system is compared with conventional coordinate measuring machines. Finally, the application area and its limits are identified for tactile on-machine inspection systems.