The Design Of Attitude Detection System For The Shipboard Satellite Antenna Servo System

This paper comes from a particular research project, the shipboard satellite antenna servo system, to study the design of attitude detection system for the shipboard satellite antenna servo system, which views Micro Inertial Measurement Unit and the Encoder Uint as the core of the attitudes measurement. To improve the accuracy of MEMS inclinometers and gyroscopes, temperature compensation and software algorithms are applied to MEMS inclinometers, alongside with hardware difference processing and software algorithms are used for MEMS gyroscopes. This article proposes solution to calibrate the zero of MEMS inclinometers and gyroscopes, calibrate electromagnetic compass through looking up table; At the same, the attitude detection system for the shipboard satellite antenna servo system is developed, supported by experimental data.This paper mainly studies the following aspects:(1) According to the stage of the development of the shipboard satellite antenna servo system, combined with the accuracy requirements of the attitude detection for the shipboard satellite antenna servo system, the reliability, size, cost and complexity of different type of the attitude detection system for the shipboard antenna, proposing to put MEMS gyro, MEMS accelerometer, electronic compass into use in the attitude detection system for the shipboard satellite antenna.(2) Hareware differential circuit and software differential circuit are designed for tilt sensor in the same series but different models. Through a large number of comparative tests, finally the attitude detection system for the ship choose biaxial software differential circuit to use, and the attitude detection system for the shipboard antenna uses single-axis hareware differential circuit.(3) When ship moves on the sea, resulting in linear acceleration. The linear acceleration interferences MEMS accelerometers, causing the test inclination angle incompatible with the real value, at the same time, the zero drift and the temperature drift are very likely to influence gyro signal in the static state, so information of inclinometers and gyroscopes is integrated through the Kalman filter algorithm.(4) Two methods of signal processing, IIR filtering and Recursive least squares fit, are suggested through error analysis of MEMS gyro signal. Then Recursive least squares fit is selected, by verifying date of MEMS gyro, using algorithm in the actual detection system.(5) Two methods of signal processing, IIR filtering and Recursive least squares fit, are suggested through error analysis of MEMS gyro signal. Then Recursive least squares fit is selected, by verifying date of MEMS gyro, using algorithm in the actual detection system.(6) Test and analyze the magnetic encoder, use high-precision turntable to compensate for magnetic encoder signal, improving the accuracy of the magnetic encoder.(7) In this paper, the error of plane electronic compass with the structure of biaxial magnetometer. Combined with the measured data in actual use, in order to improve the measurement accurary of the electronic compass, the signal of electronic compass is calibrated by magnetic encoder, which is highly accurate and stable, and compensated by the algorithm of Luo Poor.At the end, this system is fully tested, and research results and system accuracy are showed. At the same time, the shortcomings of attitude detection system for the shipboard satellite antenna servo system, and some ideas to improve the system accurary are proposed.