The Study On The Error Estimates And Compensation Algorithm In GF-IMU

The gyroscope free micro inertial measurement unit (GF-IMU) achieves system-wide navigation only uses accelerometers. GF-IMU using accelerometers measure linear acceleration, while the use of multiple accelerometers spatial location Combination of calculated angular velocity, and thus obtain all the parameters required for navigation. Conventional navigation systems are formed by gyroscopes and accelerometers. Gyroscopes are used for measuring the angular motion parameters and accelerometers for the linear acceleration. But gyroscope has inadequate of high cost, Unable to adapt to large-angle measurement, Unable to adapt to the impact of a large linear acceleration and so on. So, GF-IMU should be given more and more attention than the traditional navigation system.In this paper, the main research work is on the method of installation error parameter calibration and compensation of GF-MIMU. Fist, the work is how to calculate the angular velocity from the accelerometer outputs in GF-MIMU, according to a nine-accelerometer configuration. And it is simulated for the method; Second, It describes the system error sources, the main research work is the installation error source. It is derived theoretically and simulated for the method on calculating angular velocity and acceleration under the installation of position error and the installation azimuth error. Last, installation error is too great impact on the angular velocity and linear acceleration Solution. So, It is proposed a method which calibration error parameters of the installation location and install the orientation error parameter. And calibration results compensates to the actual output of the accelerometer. The results show that the compensated angular velocity can be more accurate information, it is greatly improved the system's accuracy.