Research On Thermal Characteristic And Thermal Error Control Of High-performance Aerostatic Motion System

With the increasing development of high performance equipment, more strict requirements was proposed for high performance precision motion system, such as the high precision, high-speed, high dynamic performance and high cleanliness. The precision motion system which use air bearings and direct drive motor has become a hot research, the related research abroad has been a wide range of industrial applications. Due to the thermal deformation error is an important factor affecting system precision, so analysis of thermal characteristics and control about thermal error of precision air movement system is very necessary.In this article, a new aerostatic direct-drive rotary stage system was designed, the thermal properties was analyzed, and thermal error was researched, the main content are as follows:(1) The3D model of high performance of aerostatic rotary stage system is designed and built; the key part of the air bearing structure is designed; preparation and debugging are completed.(2) The finite element model was built in ANSYS, the thermal deformation equation, elastic mechanics and the theory of finite element mathematic model of the rotary stage is established based on thermal deformation, laying the theoretical foundation for further analysis of the thermal characteristics of the rotary stage.(3) The rotary stage boundary conditions and the heat source was calculated through the relevant theories, the results are applied to the finite element model. Temperature field distribution of the rotary stage system were analyzed, analysis by method of the indirect coupling, the temperature field was calculated for the conditions of the thermal deformation of the rotary stage system.(4) Two ways of changing boundary condition of rotary stage system have been analyzed to find their influence on thermal deformation, which are as follows:the improvement of rotary stage system structure and forced convection cooling of the rotary stage system. Through the optimization of the two methods, the thermal error of the rotary stage system can be suppressed effectively.(5) A temperature measurement system was established, the PT1000platinum was used as resistance sensor, the experiment result show that the FEA method can used for aerostatic systems.The experimental results have proved that the thermal error control scheme proposed in this article is feasible and effective.