Investigation on an integrated approach to modelling and analysis of multi-axis aerostatic bearing stages for high precision performance

Abstract

Multi-axis aerostatic bearing stages are one of key enabling element units for precision and ultra-precision machines. These stages are essentially important for high precision positioning of the tool and/or workpiece and their dynamic and static actuation, while their higher and more robust dynamic performance is increasingly demanded. In this paper, an integrated modelling and analysis approach is presented for the multi-axis aerostatic bearing stages system. The approach is focused on addressing two folds of challenges, i.e. the integrated analysis of mechanical design, electric drive actuation through the advanced cross-coupling-controller with variable gains for a direct drive aerostatic bearing linear stages as a complete high precision mechatronic system, and the simultaneous tuning and further analysis of the multi-axis aerostatic bearing stage system through PID control algorithms. It thus aims to achieve the higher positioning accuracy, response time and stability of the stage motions, especially during the high-speed multi-axis synchronized actuations in a precision engineering application. The modelling and analysis are implemented in MATLAB/Simulink environment and further supported by advanced control functions particularly for coupling, tuning and dynamic performance analysis. The paper is concluded with a further discussion on the potential and application of the approach for high precision multi-axis stages.