Flexible Structure Design On Near-infrared Doppler Differential Interferometer

The middle and upper atmosphere(about 30-300km)is an important parameter for studying atmospheric science and environmental climate change.It is one of the important parameters used to characterize the dynamics of the atmosphere.It also affects the thermal structure,dynamics,matter and energy distribution of the atmosphere.Doppler differential interference spectroscopy technology is based on the Doppler effect,which is a new type of passive optical remote sensing detection technology with the characteristics of high throughput,high phase sensitivity,and no moving parts.The near-infrared Doppler differential interferometer based on the satellite platform uses oxygen molecules as the target source to achieve global-scale wind field detection in the middle and low thermal layers,which is an important technical approach.Due to the abundant near-infrared emission spectrum lines of oxygen molecules and the small distance between the spectrum lines,compared with the detection of the green and red lines of oxygen atoms,the near-infrared Doppler differential interferometer is required to have higher spectral resolution to ensure the inversion accuracy of data.Under the condition of the same grating dispersion rate,the size of the differential interferometer is approximately proportional to the spectral resolution.Compared with the visible light differential interferometer that uses the oxygen atom red line(630nm)as the source,the mass of the near-infrared differential interferometer is increased by 2.1 times.Facing the high mechanical reliability requirements of spaceborne applications,while meeting the optical performance and thermal stability of the interferometer,this article focuses on the research on the large-size interferometer flexible support structure of the near-infrared Doppler differential interferometer wind measurement system and the heat The specific research contents of deformation characteristics are as follows:1.The finite element method is used for analysis and comparison,and the flexible structure scheme design and key are focused on the connection between the interferometer base plate and the interferometer glass entity.Parameter optimization criteria,in the case of the same size of the interferometer,the simulation verification shows that after using the flexible structure installation plan,the static analysis of the following shape meets the requirements,the next natural frequency of the dynamic analysis is 765.9 Hz(> 100 Hz),and the acceleration The maximum response value is 26.516G(<30G),the maximum stress of the adhesive surface is1.4MPa(<14MPa),the maximum displacement value is 0.0027mm(<2.5mm),the safety factor of flexible joint design is sufficient,and the displacement and rotation angle under thermodynamic analysis Meet the design requirements(<±0.02mm).2.Combining the design plan proposed in Chapter 2 to carry out the flexible structure design for the near-infrared differential interferometer,and analyze its mechanical reliability,thermal stability and surface shape.The results show that the maximum stress value of the adhesive is 11MPa(< 14MPa);the maximum stress value of the flexible joint and the displacement value of the whole machine(80MPa,0.02mm)meet the design requirements;the accuracy of both sides of BS1 and BS2 has been significantly improved.