Estimation of excitation forces on a structure in rotating by inverse filters

Abstract

Monitoring technology such as predictive maintenance and anomaly detection during cutting process has been required. A wireless tool holder with acceleration sensors has been developed for monitoring tool vibration. To advance the device functionally, we have proposed a method using inverse filters to estimate cutting force and torque from acceleration sensor signals during machining. In this study, excitation forces (x direction force, y direction force, torque) on a tip of a structure in rotating were estimated experimentally by the proposed method. Firstly, inverse filters were determined from single-input and single-output signals by excitation experiment of static structure on the surface of which acceleration sensors were placed in circular pattern. Secondly, the excitation forces were estimated by convolving the inverse filters with the acceleration signals when the tip of the structure on rotating was excited impulsively. In addition, the force magnitude, the angle of action, and the excitation direction were calculated by the estimated excitation forces. The estimation values of the force magnitude and the excitation direction almost exhibited corresponding measurement values when the rotation speed was 60 rpm. The experimental results show that the proposed method can effectively estimate excitation forces on the structure in rotating.