A Planar Z-axis Gyroscope for MEMS Inertial Measurement Units

A planar z-axis gyroscope is necessary to develop planar Inertial Measurement Units (IMUs) for the guidance of air-deliverable munitions and armaments. An integrated IMU enables the smallest size, lowest cost, and best potential for improved performance.Together with System on Chip and embedded electronics, the full IMU can be contained in the smallest possible package. At MSSA an Integrated IMU is under development without a z-axis gyroscope. We propose to develop the z-gyroscope to meet this need. Thez-gyroscope will also be added to other IMU approaches under consideration. A particular IMU approach is based on a pyramidal mount with orthogonal faces onto which three z-gyroscopes are mounted without the need to align them since the input axis isnormal to the mounting surface. Other gyroscopes are not as attractive because their axis is normal to the mounting surface. Other advantages of the pyramidal mount are that only the z-gyroscope is needed and it is possible to use selected devices.Fabrication yield is not as important as with Integrated IMUs. The accelerometers are rugged instruments based on a dynamic tuning principle that enables high performance with the capability to withstand high-g shock The military, industrial, and consumerapplications for precision motion measurement and control are broad and valuable. These applications span missile guidance, virtual reality simulation & training, oil drilling, vehicle safety and navigation, and personal navigation. OEMs that supply theseapplications are constrained by the lack of affordable sensors with adequate performance. Low-cost MEMS gyroscopes, accelerometers, and IMUs with tactical-grade performance would enable OEMs to migrate a host of military and industrial products into muchlarger consumer markets, and to expand the number of applications that deliver economic value based on low-cost precision motion measurement. The resultant economies of scale in production and application would yield significant benefit for the militaryprograms that spawned the enabling technology.