A scheme for improving the performance of a gyroscope-free inertial measurement unit

A gyroscope-free inertial measurement unit (GF-IMU) uses only accelerometers to compute specific force and angular rate. It is a low-cost inertial system, but its measurement error diverges at a rate that is an order faster than that of a conventional inertial system equipped with gyroscopes. In this paper, a redundant accelerometer-aided gyroscope-free IMU is designed to achieve a stable and bounded system. In this system, a three-axis accelerometer is used in addition to a set of six accelerometers that is typical in a conventional gyroscope-free IMU. The linear error dynamics of this aided gyroscope-free IMU is derived, and the effects of accelerometer errors are analyzed.