Research On The Mechanical Characteristics And Motion Control Of The Air Bearing Micro Cutting Platform

Micro products have been widely used in bioengineering, medical equipment and aerospace areas. Micro cutting technology is one of the main methods which could realize micro products’ effective and high precision fabricating. Micro machine tool’s processing performance has important effects on products’ quality. Based on the self-develop air bearing micro cutting platform, the mechanical characteristics of the aerostatic bearing and the motion control are researched. The verification micro cutting experiment is also conducted. The main research work is as follows:1. An air bearing micro cutting platform is developed according to the requirement of micro cutting. In the cutting platform, the marble base improves the holistic vibration suppressing performance; the aerostatic bearing realizes the near-zero-friction movement between the sliding block and the slide; the linear motor decreases platform’s transmission error; the open motion control system realizes the two-axis cooperation and motors’ stable computation.2. The mechanical characteristics of the aerostatic bearing are researched. The inherent relationship between the first five step natural frequency of the cutting platform’s moving component and the inlet air pressure is revealed. Based on the Fluent simulation, the nonlinear pressure distribution in the air film area is researched. The air film’s bearing capability and stiffness under different air film thickness are analyzed through the bearing capacity testing experiment.3. The model which could represent the dynamics of the cutting platform’s moving components is established, then a two-degree-of-freedom control strategy is employed. The controller’s control performance is analyzed and the parameters are tuned in the Simulink simulation. The verification experiment demonstrates the cutting platform’s desirable positioning accuracy and velocity stability under two-degree-of-freedom controller whose parameters are tuned.4. The optimizing of the controller parameters improves the platform’s capability of machining under high load and suppressing the moving components’ vibration, which could enhance the cutting force measurement accuracy. The micro turning experiment shows that the air bearing micro cutting platform could fulfill the requirement of micro cutting.