Simulation and Analysis of Accelerometer Bias Estimation in Inertial Navigation System

The Inertial Navigation System (INS) is a navigation system that determines the position, velocity, and orientation of a moving object without the aid of outside references. It does this by using gyroscopes and accelerometers. The most severe errors of INS are Direct Current (DC) offset or bias drift and scale factor variation. The estimate and correction of these limitations are necessary for accurate navigation. While measuring these errors measurement noise and process noise are the error sources that affect the measurement. The proposed method for measuring the bias from the accelerometer uses a Kalman filter. Estimation is done by using the Kalman filter, which has the predict and update stages, a recursive filter that uses state space techniques. Three accelerometer output is used for analyzing the bias factors of all three axes of INS. Accelerometer output is filtered using a Kalman filter to get the noisy free output. The proposed method effectively filters out the noises which present in the measurement and can estimate the accelerometer bias without the help of a turntable.