Comparison of Motion Behaviors of a Machine Tool Examined by Position Acquisition Device (PAD) and Laser Interferometry System (LIS)

With increasing needs of data acquisition for a legacy machine, the position acquisition device (PAD) developed was used to record the motion behaviors of a machining tool. The PAD has a real-time (RT) controller with field programmable gate array (FPGA) input/output modules, which can real-time record the motion behaviors of linear, rotary, and multi-axis simultaneous motions. In this study, to verify the PAD, a laser interferometry system (LIS) was employed to exam the linear motions of the machine tool and compared the results with the PAD. Both the measurements indicated that the feeding speed fluctuated in a certain range. In addition, the experiments for examining the repeatability of linear motions were performed to demonstrate the effectiveness of the PAD. Compared with the LIS, the PAD features cost-effectiveness and easy-to-use. It can be applied to the Industry 4.0 production for data collection and enable a legacy machine with position sensing function for developing a smart machine.