Low Cost, Strapdown Integrated Seeker

The cost, mass, and performance of the homing seeker in systems such as THAAD are primarily driven by the requirement for precision target detection, tracking, and imaging for aimpoint selection in the presence of shock and vibration from aerodynamic buffeting and propulsion system operation. During the Phase I effort, Radiance designed a high bandwidth Fast Steering Mirror (FSM) utilizing a new class of piezoceramic actuators with demonstrated mirror deflections mechanically amplified 4.5 times that of conventional piezoceramic actuators for the same input voltage. Results from testing of a single-axis prototype suggest significant improvements in power efficiency, size and mass reductions, and thermal management over comparable electromagnetic voice coil systems, and represents the first step in the progressive development of a flight-worthy system. The progressive demonstration in Phase II will include: demonstration of the amplification factor; integration of a microradian-accuracy measurement sensor; and development and demonstration of the power supply/controller and two-axis FSM design. The design objectives will include the performance objectives stated above for a FSM weighing less than 250 g (excluding the mirror) and requiring less than a 60 W power draw. A fast steering mirror meeting these objectives will produce a significantly higher bandwidth than an electromagnetic (voice coil) FSM meeting the other objectives. Such a system enables a kill vehicle (KV) to rapidly scan a large search area and to simultaneously track many objects. Incorporation of the micronradian-class precision measurement sensor yields pointing accuracies sufficient to direct laser pulses toward the many targets and retrieve range information. Furthermore, reduced heat generation due to the increased power efficiency associated with incorporation of the mechanical amplification serves to reduce thermal noise on the steering mirror and the other optical elements within the seeker. This noise reduction in turn serves to increase the detection range of the system.