Input-shaping-based improvement in the machining precision of laser micromachining systems

Abstract

Laser machining is widely used in micro/nanomachining owing to its noncontact nature, environmental friendliness, high level of automation, and short process time. Notably, for micro/nanomachining, the precisions of both the laser and optical systems and motion control systems are crucial. Typically, residual vibrations generated during the motion of machine parts reduce precision at the micro/nanoscales. The input-shaping method is simple and effective for reducing such residual vibrations. Hence, traditional input-shaping methods are primarily used in flexible systems, such as cranes, robots, and motion systems. This is because a flexible system has a low rigidity, damping ratio, and natural frequency; thus, its residual vibration is higher than that of a high-rigidity motion system. In this study, residual vibrations were reduced by applying the input-shaping method to a high-rigidity motion system for precision laser machining. A modified zero-vibration (ZV) shaper was used to apply input shaping to the high natural frequency of a high-rigidity motion system. The modified ZV shaper was evaluated, and its residual vibration suppression performance was confirmed based on its application to a flexible system. Furthermore, errors caused by accelerations in corner machining were quantified, and residual vibrations were suppressed via the application of the modified ZV shaper.