Research On MEMS Rotating Modulation Navigation System Based On Miniature Ultrasonic Motor

Constrained by the volume and power consumption of microsatellite,it tends to use the systems of low-cost and low-performance,which greatly limits the application and promotion of microsatellite.In this paper,a MEMS rotary inertial gyroscope with low cost and low accuracy is rotated by a high precision and torque micro-ultrasonic motor turntable,to form a miniature rotary MEMS navigation system,and then to realize the high accuracy application of the low cost inertial navigation system.Firstly,the research status of rotation modulation navigation system at home and abroad is studied,and the theoretical model of the rotating modulation and navigation system is analyzed.The different modulation schemes and the influence factors of the rotation modulation are simulated and analyzed.The optimal modulation scheme suitable for low precision MEMS navigation system is proposed.Based on the quaternion attitude dynamics,the application model of the rotating gyro in the satellite attitude measurement system is deduced.Simulation results show that the rotation modulation technique can improve the accuracy of MEMS gyroscope more than an order of magnitude.Secondly,the influence of turntable control accuracy on the accuracy of rotary-modulated navigation system is analyzed theoretically.A high-precision turntable is one of the key technologies to improve the effect of rotary modulation.In this paper,a high precision,nonmagnetic micro-rotating turntable is developed by using a new type of ultrasonic motor.The nonlinear control of the turntable is realized by using PID technology.The angular velocity accuracy is of 10-3 order of magnitude,the angular position error is in the order of 0.01°,the response time is better than 40",and the repeatability of reciprocating rotation is very good.Finally,a miniature rotary modulation navigation system is built by using the ultrasonic motor turntable and ADI inertial measurement module.The results show that the rotary gyro can improve the accuracy of attitude measurement and extend the application range of MEMS inertial components in aviation and aerospace field.It provides a theoretical basis for the development of low-cost,medium-precision navigation systems suitable for micro satellites,and has a certain role in promoting its development.