Low Cost, Radiation Hardened, Noise Resistant Inertial Measurement Unit

Space Photonics, Inc. (SPI) is proposing development of a revolutionary integrated optical encoder-IMU that is the “last piece of the puzzle” for applying our beam steering technologies to long distance link systems (GEO-to-GEO, GEO-to-LEO) and high-precision IR object tracking. This MEMS sensor innovation utilizes an optical encoding technique whereby an optical fiber input and an optical fiber “collector” are used to measure variations in optical power induced by relative motion of an illuminated encoder. The collected signal varies in optical intensity based on the motion and acceleration of the beam steering system, thereby providing not only precise (e.g., gimbal) position information but also vibration/jitter data. This innovation will enable very fast acquisition and tracking over very long distances through the precise measurement and compensation of initial pointing errors (by autonomous knowledge of vehicle location and orientation) and vibration induced vehicle errors. Further, our compact, low power integrated optical encoder-IMU design effectively addresses the three primary problems with existing IMUs; integration errors, lack of co-location with the pointing device (end-effector), and electromagnetic interference (EMI). This greatly improves the precision and significantly reduces the corruption of measurement data into the controller. Another benefit is that this device may be incorporated in any existing system as a drop-in enhancement (e.g., as a low-level, autonomous device in the control loop).