Compact hybrid reluctance based tip/tilt actuator for large range fast steering mirrors

This work presents a compact tip/tilt fast steering mirror (FSM) based on a linearized hybrid reluctance actuation topology. The actuation principle is analyzed using a magnetic equivalent circuit model and finite-element method simulations. The proposed design achieves a large range of $\pm 5/10$ deg (mechanical/optical) with an optical aperture of 1 × 1.5 inch, delivering higher torque and linearity compared to the state of the art. To maintain compactness, the system uses magnetically coupled axes while achieving a decoupling of over 30 dB. Independent control loops for each yield position bandwidths of 1.06 kHz and 1.13 kHz, enabling a precision below 1.2 mdeg, and Lissajous scanning up to 110 Hz with 4 deg. Overall, the compact FSM demonstrates the highest range-bandwidth product (+22%) with the largest range of hybrid reluctance actuated systems.