Research On Test And Calibration Techniques Of Fog

Fiber optic gyro has become the new mainstream instrument. The techniques of hardware design, initial alignment, testing and calibration of the Fiber inertial measurement unit are the keys to research the optical strap-down inertial navigation system. In this paper, modeling and testing experiment for the random errors of fiber optic IMU are presented and error parameters are obtained, which improve the accuracy of the navigation system.Firstly, based on analyzing the requirements of the system, the signal acquisition circuit of fiber optic IMU, with the technology of SOPC and FPGA, is designed. Then the hardware and software for collecting data from fiber optic gyroscope and accelerometer are constructed.Secondly, in order to improve the efficiency of calibration and testing experiment, the software of automatic calibration and testing is designed, which includes the interface of data acquisition under the Delphi programming environment and the interface of real-time controlling turntable under the Visual Basic programming environment.Thirdly, a series of experiments are designed to test and validate random noise of the fiber optic gyro. The Allan variance method and the method in the National Military standard are adopted to calculate the experimental data to obtain the error parameters.At last, through the calibration of fiber optic IMU, the scale factor, zero-bias, mounting error angle and other information are obtained. With such parameters, the navigation algorithm is implemented to verify the calibration results. The results algorithm indicates that the data transmitting from acquisition system is accurate and reliable. The segmented compensation is presented and the output errors are smaller than before. Furthermore, the calibration result is correct.