Design and characterisation of a compact 4-degree-of-freedom fast steering mirror system based on double Porro prisms for laser beam stabilization

This paper proposes a 4-degree-of-freedom (DOF) actuator for a fast steer mirror (FSM) compensation system in order to compensate for 4-DOF laser errors. The mathematic system modeling was built to design and predict the performance of the proposed 4-DOF FSM. Finite element analysis was performed by using a commercial software to analyze the characteristics of the electromagnetic structure and mechanical structure for the proposed 4-DOF FSM. This study further verifies the properties of the proposed 4-DOF FSM by using a laboratory-built prototype. The proposed 4-DOF FSM has the travel range of +/- 5 mrad and +/- 0.04 mm along X and Y axes with accuracy of 0.025 mrad and 0.0012 mm and the bandwidth of rotational part and translational part are 10 Hz and 39 Hz, respectively. (c) 2021 Elsevier B.V. All rights reserved.