High-accuracy heading determination

In a system of systems context, a variety of applications are dependent on the knowledge of location and attitude of individual agents in order to collaborate. For example, a soldier on the battle field observing a potential target transmits this information to a base station which then is shared with an unmanned air vehicle for surveillance. Without precise knowledge of the soldier´s position and azimuth angle to the target, the handoff to the UAV would not carry much merit. The availability of low-cost MEMS inertial measurement units (IMU) increases the feasibility of realizing a compact inertial navigation systems (INS) capable of operating in a variety of environments, including GPS degraded or denied scenarios. Due to errors in the IMU, it is very challenging to self-initialize the attitude of the device in a reasonable time frame. In this paper, we present a novel approach that utilizes a unique magnetohydrodynamic (MHD) angular rate sensor (ARS) in a carouseling configuration in order to perform attitude self-initialization to within 4-milli radians in less than a minute. Further more, real environmental issues, such as platform vibration and base motion (e.g. sinking) are also addressed.