Abstract:
In response to the on-orbit reconfiguration challenges faced by future large aperture segmented optical systems, a lightweight design method with a wide range of curvature adjustability is proposed. This study initially analyzes the relationship between the characteristics of piezoelectric ceramics and the constitutive equations of thermal strain, deducing that piezoelectric strain can be precisely equivalent to thermal strain. Based on the flexural curve equation, the deformation of piezoelectric ceramics is calculated, enabling the parameterized modeling of an ultra-low expansion (ULE) glass segmented mirror with an edge distance of 510 mm and a curvature radius of 9000 mm. Simulation results indicate that 54 interlaced actuators can achieve a curvature radius reconfiguration of 240.07 mm with a control voltage range of ±20 V, exhibiting a highly linear relationship. Experimental results further demonstrate that when the control voltage is varied between -25 V and 20 V, the change in the curvature radius of the segmented mirror reaches 233.44 mm, with the positive unit voltage corresponding to a greater change in curvature radius than the negative. The proposed method for a wide range of curvature adjustable segmented mirrors provides new insights for the engineering application of large aperture segmented optics in on-orbit reconfiguration.