| With the acceleration of China’s exploration of the space field,the resolution requirements for space optical telescopes are also getting higher and higher.Today’s mainstream optical telescopes mainly use splicing technology to synthesize the main mirror required.Thin film sprites are "folded" due to their own characteristics that are susceptible to temperature and vibration in the orbital environment,so it is particularly important to develop a soft tensioning platform that is more compact and easier to control than the current solution.This paper is based on such application requirements,the design of a soft multi-dimensional tensioning actuation platform based on the supple mechanism technology,compared with the tension actuator for optical films at home and abroad,it avoids the energy loss and load increase caused by the joint drive of multiple actuators.In addition,the advantages of integrated processing of the supple mechanism and frictionless wear also ensure the realization of the kinematic performance of the tensioning platform.Further,the design of the synergistic vibration isolation superstructure achieves output stability of the tensioning platform.In order to realize the design of the soft tensioning platform scheme that meets the application requirements,first of all,on the basis of the selection of flexible hinges,the selection of materials,the selection of soft amplification mechanisms and the selection of intelligent material drivers,the flat three-stage soft scaling tensioning operation scheme I was designed,and the spatial tensioning operation scheme was designed after analyzing its advantages and disadvantages to meet the application needs.Finally,the displacement amplification mechanism is briefly introduced by using the pseudo-rigid body model method.In order to further optimize the performance of the soft tensioning action platform,the orthogonal test data of the optimized size is generated by sensitivity analysis,and on this basis,an optimization mathematical model is established,and the optimization function is used in Matlab to solve the optimized size according to the actual application environment.The tensioning platform is followed by a systematic modeling of the tensioning platform,and the first-order natural frequency expression of the system is obtained from the kinetic analysis and the Lagrange equation.Finally,the static analysis and modal analysis of the soft tensioning platform are carried out,and the motion amplification ratio and natural frequency of the tensioning platform are obtained.Then,the vibration-suppressing superstructure of the tensioning platform is designed and analyzed.After the superstructure model material is determined,on the basis of the theoretical analysis of the superstructure equivalent single degree of freedom model,the mechanism analysis of the equivalent four-degree-of-freedom superstructure model is carried out,and the influence of superstructure parameters on vibration isolation performance is discussed.Based on the above research conclusions,four types of superstructure schemes are proposed and their finite element harmonic response analysis is proposed,the ideal superstructure scheme is selected based on the vibration isolation effect,and the optimization scheme is improved,combined with modal analysis and harmonic response analysis,which proves that it has good vibration inhibition potential in the expected low frequency range.Finally,the dynamic performance of the soft tensioning platform is simulated and analyzed and its vibration suppression performance is simulated and verified.Firstly,multiple sets of static analysis were performed on the tensioning platform,and the response displacement under different displacement excitations was linearly related.Then,by tightening the platform input amplitude value and the sinusoidal excitation of the variable frequency,the platform has good displacement output stability.Finally,the harmonic response analysis and transient dynamic simulation under different sets of excitations are used to verify that it has a good vibration suppression effect. |
