Calibration Research on a 10-Axis Laser Gyro Redundant Strapdown Inertial Measurement Unit
According to calibration problem of ten redundant laser gyroscopes'three-autonomy'strapdown inertial measurement units,A calibration model and calibration scheme are deduced,which includes five-axis gyros and five-axis accelerometers.The ten-axis redundant inertial measurement unit is divided into two groups known as straight assemble X\Y\Z and oblique assemble S\T.A system level calibration method is adopted for the straight assemble,by establishing a state equation about the calibration error model,taking navigation speed error as the measurement,and estimating the calibration error parameters through Kalman filtering.Using the calibration results of the straight assemble as reference,separate calibration models are established for the accelerometer,gyros scale coefficient and gyro bias.Finally,the calibration of ten re-dundant laser strapdown inertial units is verified by combining the 19-position system-level calibration meth-od with the discrete calibration method.The calibration results are correct and the characteristics of the cali-bration errors are analyzed.