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An acceleration Feedback(AFB) is introduced to the servo system to improve the dynamic performance of a moving base optoelectronic stability platform.As it is difficult to establish a model for the moving base optoelectronic platform according to a moving object,the proposed acceleration feedback is realized by measuring angle acceleration signals directly.Simulation and analysis indicate that the dynamic stiffness of servo system can be enhanced and the starting and braking performance is improved with the AFB.Experiments show that the capability of resisting friction moment is increased significantly.The capability of resisting periodic disturbance is increased by 9.3db and the overshoot of speed step response is decreased by 4.9%,while the transition process has been greatly improved.The servo system has simpler structure,higher robustness,and shows better universality.

In order to improve the measuring accuracy of a steel ring reflective grating,a grating signal compensation system is designed.The system is used to compensate the signal amplitude,DC voltage and the phase of the grating,respectively,for which two grating signals have a better orthogonality.First,according to the sampling method for steel ring reflective grating signals,an electronic processing system is created.And then several compensation algorithms are established aiming at the signal amplitude,DC voltage and the phase.By taking the steel ring reflective grating with 8 192 lp/mm as a platform and the results of testing precision as a basis of adjudication,the proposed signal compensation system is verified.The results show that the precision compensated has been improved by 2.28″ with an increasing magnitude of 50%.Obtained results prove that the signal compensation system is feasible.

A centrifugal coating technology was researched to coating the uniform thickness photoresist on a concave spherical surface.Firstly,the critical factors affecting the uniform of photosensitive resist and the film forming force were investigated.Then,the centrifugal glue adhesive force during the flow state was analysed in the spherical photoresist spin coating down opening based on the hydrodynamic theory.A mathematical model to describe the relationship among the film thickness and centrifuge speed,viscosity of photoresist and the spin coating time was derived.Finally,in order to verify the correctness of the formula,some experiments of photoresist spin coating on the K9 glass concave sphere with a diameter of 120 mm,radius of 300 mm,vector height of 12.5 mm were performed.The experimental results certify that the proposed theory is consistent with the actual situation well.On the theoretical analysis,the uniform film thickness on the inner surface of an entire sphere can be obtained with the disalignment of photoresis pin coating axis and the main axis of electric engine.When the viscosity of photoresist is 1.1~1.9 Pa and the speed of main axis is 3 000-6 000/r·min-1,the uniform film thickness is 0.5~1 μm on a concave sphere.

In order to reduce the influence of vibration on the image quality and precision stability of a airborne electro-optical surveillance platform,a vibration damping design was performed.Based on the detailed analysis of complex damping theory,a two-grade damping system between the inter and outer frames of the platform was designed to isolate the vibration from inter frame to outer frame effectively in view of the shortcoming of the single-stage vibration isolation system.By using the two-dimensional parameter optimization method,the optimum natural frequency ratio fopt and the optimum damping ratio ζopt of the vibration damping system were calculated to be 1.43 and 0.243,respectively.Finally,the vibration damping effect was illustrated through a vibration test.Compared with the previous single-stage vibration isolation system,experimental results show that the maximum vibration transmissibility of vibration damping system is lower by 50%,the frequency range of vibration transmission rate less than 1 is wider,and the amplitude range of transmissibility on high frequency is much better than that of the single-stage vibration isolation system.It is concluded that the vibration damping design is feasible and effective for electro-optical surveillance platforms.