Research On The Construction And Integrated Simulation Technology Of Space Interferometry Measurement Platform

The space laser interference ranging system is one of the key technologies of space gravitational wave detection and the source of the scientific signal of gravitational wave.Ground-based gravitational wave measurement is limited by the earth’s gravity and the size of the scale,the range of gravitational waves detected is mainly concentrated in high frequencies,and its sensitivity is difficult to extend to within 1HZ.Space gravitational wave detection is an option to understand the nature of a wider range of gravitational waves and wave sources.For space interferometry systems,in order to reduce the optical-process coupling noise of the system,the noise suppression method needs to be considered during the design phase of the scheme,and the beam is required to have more stringent absolute position accuracy.At the same time,in order to ensure that the system can function in orbit,the interferometry platform is usually required to have sufficient structural strength and stability to resist the damage of emission offset and the impact of space environment disturbance.Therefore,it is the key to guide the system optimization design and construction by integrated simulation means.In order to develop China’s space gravitational wave detection plan,the Chinese Academy of Sciences formally put forward and launched China’s space gravitational wave detection "TaiJi 1 program".In this paper,the space TaiJi program technology verification satellite "TaiJi 1 program" as the research object,the space interferometry platform construction process involved in the key technology research,to ensure that the space interferometry measurement system in the target frequency band of 10 mHz-1Hz to achieve the position measurement accuracy of the 10 p meters.The main research work of this paper is as follows:In this paper,the optical scheme of the space interferometry platform is analyzed and simulated.Based on theoretical derivation,various noises affecting the stability of the light range of the system are discussed.The corresponding suppression method is considered to effectively suppress the ambient noise and frequency noise of the system.Based on the basic principle of laser Gaussian beam,its interference signal is analyzed and calculated,and the necessary scientific signal is defined for system simulation and construction.The optical simulation link is established and the correctness is verified by numerical analysis method.The structural design of the space interferometry platform is studied as an integrated optimization.In view of the initial structural design scheme,the system’s main support structure is lightweighted by combining topological optimization method and parametric modeling method.The sensitivity analysis of structural parameters is carried out for different performance indicators,which makes the optimization design scheme improve the lightweight degree relative to the empirical design in the case of meeting the mechanical and conditioning indicators.This paper analyzes the effect of in-orbit temperature fluctuation on the measurement accuracy of the system,and constructs the integrated simulation model of the system light machine heat combined with the finite element analysis software.The space temperature fluctuation is simulated according to the thermal control index,and the system light range stability is the target function.By calculating the optical range noise caused by changes in structure size and component refractive index in extreme cases,it is proved that the system scheme design has sufficient thermal stability.Aiming at the problem of absolute position measurement of space beam in specific coordinate system,a scheme of absolute position measurement of space beam based on three coordinate measuring machine is proposed,and the prototype is developed.Further improvements are proposed,including the replacement of the refractor and the setting of the magnifying glass.Based on the hydroxide catalysis bonding technology,a targeted assembly scheme is proposed,and an integrated interferometer prototype is built,with a measurement accuracy of 6 pm/(?).On the basis of the above-mentioned research,the engineering integration and environmental test of the interferometry platform are completed.According to the sensitivity analysis method,the key division and tolerance distribution of the device are carried out,and a targeted adjustment scheme is proposed.Finally,the integrated interferometry platform was tested with force and heat,after the test,the signal contrast of the measuring platform was still greater than 80%,and the measurement accuracy was better than 400 pm/(?) in the measurement band,which meets the design index requirements of "TaiJi 1 program" of ~100pm/(?) pm level.