Abstract: The camera extension mechanism needs to obtain and maintain sufficient stiffness and dimensional stability after unfolding and locking, and at the same time, for the demand of high precision and high spread ratio of specific space optical remote sensing camera, a one-dimensional space optical remote sensing camera with high precision, high spread ratio extension support mechanism and high stiffness volute springs is designed to realize the elimination of the hinge gap and the maintenance of high stiffness of the structure after unfolding. The extension support mechanism uses a scroll spring to drive the folding spreading bar to realize the mechanism unfolding, a speed control mechanism to control the speed of deploying, and a hinged positioning surface to locate the hinge when deployed, with the residual driving force of the scroll spring and the tension cable to maintain the stiffness. The unfolding dynamics analysis, modal analysis, unfolding accuracy analysis considering the length error of the member and the hinge rotary gap, and thermal deformation analysis under the working environment are carried out for the unfolding support mechanism. The camera extension support mechanism is completed, and the base frequency of the mechanism is above 20Hz. The ground repeatable unfolding accuracy of the prototype extension mechanism is measured, and the unfolding accuracy is better than ±0.05mm. The performance of the extension support mechanism is good, and it can satisfy the requirements of the special tasks of the space optical remote sensing camera.

Key words: extension support mechanism, dynamics, modal analysis, precision analysis, repetitive deployable accuracy measurement