Duration: 18 months
Today’s state-of-the-art Fast Steering Mirrors (FSM) actuation is based on at least three actuators for achieving two or three degrees of freedom (DOFs) of the mirror, namely tip, tilt, and, optionally, piston. Most designs employ four actuators in a push-pull configuration. Regardless of the underlying actuation technology, all FSM share this practice [1 .. 7]. Each actuator necessitates the assembly and alignment of multiple components, a resource-intensive process that scales with the number of actuators. This proposal introduces an innovative alternative. By employing distributed actuation uniformly applied along a circumferential path, with arc regions that can be defined as needed and independently controlled, this actuation approach: · creates flexibility, enabling performance optimizations and · streamlines its implementation by essentially decoupling the number of independently controlled actuation forces from the complexity of the physical structure. To illustrate the concept, refer to the coil structure in Fig. 1, featuring a cylindrical coil with uniformly distributed rhombic turns. This coil is electrically sectioned as needed and integrated in the actuator arrangement of Fig. 2. This arrangement facilitates the interaction between the magnetic field and the current flowing through the coil’s conductors. The result is the generation of Lorentz forces within the conductors and reaction forces on the moving magnet via its magnetic field. These forces are aligned with the cylinder’s longitudinal axis and act along the circumferential path of the cylindrical coil. Positioned at angles corresponding to each electrically sectioned portion of the coil and independently controlled in both amplitude and sign, these forces enable precise manipulation of tip, tilt, and piston DOFs of a mirror connected to the moving magnet (in closed loop). The cylindrical coil can effectively conduct heat to a support base, allowing higher current density.
