Dynamic Disturbance and Error Analysis of Flexible Support System for Large Optical Mirror Processing

Featured Application This study adopts the method of mathematical model-simulation-experiment to study the non-linear influence relationship between the ambient temperature and the air content in the working medium. The parameters of the model are modified by simulation analysis and combined with experimental parameters to verify that the established mathematical model can be consistent with the actual working conditions. The established mathematical model provides a theoretical basis for the subsequent modal analysis of the flexible support system (FSS) and provides an experimental basis for the design of the controller and the study of error compensation control strategies. At the same time, this method can be extended to studies on the error mechanisms of other nonlinear, time-varying, uncertain, and externally disturbed systems. To improve the accuracy of a flexible support system (FSS) used for optical mirror processing, the influence of air content in the working medium and ambient temperature change on the FSS is analyzed and studied. First, the disturbance model of the FSS and single support cylinder affected by different air contents in the working medium and ambient temperature is established, and the mapping relationship between the influencing factors and the affected factors is analyzed. Then, the effects of ambient temperature change on volume, support height, and support pressure for different air contents are simulated and analyzed separately. The results of the simulation obtained show that when the working medium is mixed with different volume fractions of air and the ambient temperature changes, upper and lower chamber volumes, support rigidity, and support height of the support cylinder are also changed. Finally, an experimental study of pressure changes in the upper and lower chambers, support height, and support rigidity changes at different ambient temperatures and air contents are carried out. By measuring the support height, support pressure, and support rigidity error, the effectiveness of the established mathematical disturbance model of FSS is further verified. It not only provides a theoretical basis for improving the support accuracy of the FSS but also provides a foundation for the application of the FSS in the processing stage of large optical mirrors.