Precision Navigation Grade Fiber-Optic Gyroscope (FOG)

Development of a Precision Fiber Optic Gyro (PFOG) is proposed. The precision in the proposed PFOG is obtained by basic design and physical construction. It is a closed loop gyro where instead of measuring the Sagnac phase shift, we drive it zero continuously, thus, this driving effort becomes the measure of the angular rate. It is made up of fiber spool and a single chip hybrid. This eliminates many interfaces, and puts all the key components together, thus, reducing the errors introduced thermal gradients across the gyro. It also makes the gyro easy to assemble (only two guided splicing) and rugged in construction. The single chip hybrid consists of a LiNbO3 and silicon substrate bonded together via a strain relieved interface. Optical paths and components are micro machined in substrates using surface diffusion and bulk micromachining. Detailed design, analysis of a potential PFOG including some hardware experiments will be performed in Phase I to demonstrate the feasibility of the gyro. The device has many defense and commercial applications. It can be used in the emerging munitions systems to sense the high rates and to improve their guidance and control.