Development and testing of a stationary dynamometer using cross-beam-type force-sensing elements for three-axis cutting force measurement in milling operations

Abstract

This study focused on the development and testing of a stationary dynamometer using force-sensing elements capable of measuring three axes of cutting force during milling operations. The force-sensing element was based on the Maltese cross-beam concept but has been improved and modified to increase sensitivity and reduce interference or cross-talk error. A Finite element analysis was conducted to study strain distribution and determine sensor positions in the force-sensing element. By using four force-sensing elements and several piezoresistive strain sensors, a stationary dynamometer prototype was constructed. A series of calibration tests were performed to evaluate the dynamometer’s sensitivity, linearity, hysteresis, and repeatability over three orthogonal axes. The dynamometer’s dynamic features and functionality for milling applications were examined through modal analysis and real milling tests. Additionally, the end-milling and slot-milling cutting force values were compared to those of a reference dynamometer (Kistler 9129AA). Overall, the experimental results indicated that the proposed stationary dynamometer is a reliable and accurate alternative for measuring cutting force during machining operations and other force measurements.