摘要: |
Because GPS is subject to periodic failures, its use in replacing all or part of ground-based navigation for general aviation depends upon developing satisfactory backup systems. A great technical challenge for low-cost GA autonomous navigation is the need for accurate, low-cost gyroscopes. To try to develop low-cost gyroscopes researchers are focusing on MEMS technology. This paper reports the status of one such research program at the University of Alabama. The UA research program proposed improving the accuracy of MEMS gyroscopes in three ways: (1) increase mass of the gyro, that is, produce a meso-scale gyro using MEMS technology, (2) increase signal amplitude by using piezoelectric actuators and sensors (instead of conventional electrostatics), and (3) use alternatives to Silicon (for example, Quartz) that should reduce accuracy degradation caused by temperature changes. The following is a summary of the status of the development effort. Sections are devoted to fabrication issues, materials development, electronic system development, simulation, and test results. To overcome the technological challenges in building the UA X-post Gyro the following must be achieved: . Design and construct an electronic system capable of measuring both relatively large and extremely small rates of rotation . Develop a computer simulation capability to be used for device design and future design optimization . Develop the capability of producing high-quality thin films of piezoelectric materials . Develop MEMS-technology fabrication processes that have never before been done . Develop a MEMS clean room for production of the gyro devices . Develop a Navigation Laboratory capable of testing MEMS-technology gyroscopes . Develop a laser trimming system for improving the performance of the manufactured MEMS-technology gyroscopes. |