In inertial navigation (INS), initial bias refers to the constant sensor error present at the start of operation, particularly in gyroscopes and accelerometers. This bias can cause navigation drift, affecting position, velocity, and orientation accuracy over time.
Sources of Initial Bias in INS
Gyroscope Bias – Small errors in measuring angular velocity lead to incorrect heading estimation.
Accelerometer Bias – Tiny deviations in acceleration measurements cause position drift.
Manufacturing & Environmental Factors – Sensor imperfections, temperature variations, and aging contribute to bias errors.
How Initial Bias Affects INS Performance
✔ Causes Position & Heading Drift – Even a small bias accumulates over time, leading to significant navigation errors.
✔ Reduces Long-Term Accuracy – Without correction, INS performance degrades in GNSS-denied environments.
How to Correct Initial Bias in INS?
✔ Calibration Before Deployment – Pre-calibrating sensors minimizes initial bias errors.
✔ In-Field Bias Estimation – Using Kalman filters and sensor fusion to correct bias dynamically.
✔ GNSS & External Aiding – GPS updates reset drift errors, improving INS accuracy.
