Micro-Optomechanical Orientation Sensor

The U.S. Army is seeking innovative autonomous onboard orientation sensors for munitions and other orientation measurement applications as alternatives to rate gyros and GPS. Conventional rotating wheel accelerometers lack long-term reliability, and are limited in accuracy and resolution. Precision fiber optic and ring laser gyroscopes are too expensive and too large for use in most munitions. MEMS accelerometers fabricated by surface micromachining are too thin to be sufficiently accurate. To address this need, Physical Optics Corporation (POC) proposes to develop a new cost-effective Micro-OptoMechanical Orientation Sensor (MOMOS) based on a grating and an integrated optical chip, capable of measuring angles less than 0.05 mrad. MOMOS is a novel design and integration of commercially available microelements, diode lasers, microlenses, and photodetectors in a waveguide or free-space configuration, with a Bragg grating element mounted on a bulk micromachined torsion base. This new design overcomes the limitations of bulk (3D) MEMS, increasing angular sensitivity and accuracy by orders of magnitude. In Phase I, POC will design, fabricate, and test the proposed angular orientation sensor technology, and demonstrate its feasibility by analytical calculation, computer modeling, and experiment. In Phase II an advanced MOMOS prototype will be fabricated and field tested.