Research On High Stability Temperature Control Technology For Optomechanics

Space cameras are the main payloads for applications such as ground observation,atmospheric and ocean detection,and cosmic detection.According to different detection requirements,camera observation accuracy and imaging quality also have different requirements.The influence of the temperature of the optical machine on the imaging quality of high-precision cameras has attracted wide attention.When the temperature changes,the radius of curvature of the lens surface,the thickness of the lens,and the refractive index of the optical material will change,this will cause the focus deviation and the system misalignment,which leads to blurry camera imaging,and even imaging failure in severe cases.As more and more occasions demand space cameras with wide field of view and high resolution,optical machines have put forward higher requirements for temperature control stability.In response to these problems,this thesis studied the following aspects of the temperature control technology of the space optical machine:First,the research established a mathematical model using heat transfer theory for the opto-mechanical structure(Frame)of a space opto-mechanical machine that uses active thermal control measures for precise temperature control.Because the established mathematical model of the frame temperature control system changes with the change of the ambient temperature,the optimal PID controller parameters will change accordingly.In view of this phenomenon,this work combines the PID parameter tuning method with the mathematical model of the space optical machine,and proposed a self-adaptive PID temperature control algorithm based on the space opto-mechanical thermal model,making the parameter self-tuning of the PID temperature control algorithm more concise.Then,the adaptive PID temperature control method based on the opto-mechanical thermal model is applied to the temperature control of the frame,and the relationship between the PID parameters of the best dynamic response and the temperature of the shade and the frame is obtained.The performance of the temperature control method was verified through simulations when the temperature of the hood changes periodically.Finally,the adaptive PID temperature control method based on opto-mechanical thermal model was applied to the temperature control of the frame and the experiment was verified.The results show that the temperature control method can achieve the stability of the temperature control of the frame is ± 0.1 ?,indicating that the method has good adaptability and temperature control stability to the changes of the mathematical model parameters caused by the change of the ambient temperature.In the end,the full text is summarized,and the improvement direction of the shortcomings is put forward.