Читать книгу Global Navigation Satellite Systems, Inertial Navigation, and Integration - Mohinder S. Grewal - Страница 46

Integration of gyro outputs (to maintain the attitude solution) and accelerometer outputs (to maintain the velocity and position solution) is done digitally. This is relatively straightforward for integrating accelerations and velocities in inertially stabilized Cartesian coordinates for gimbaled systems, and gimbal servo control takes care of the attitude solution. Otherwise, more sophisticated integration methods are required for maintaining the required coordinate transformation matrices in strapdown systems.

Because sensor output errors are being integrated, the resulting navigation solution errors tend to accumulate over time. Performance of INSs is generally specified in terms of navigation error growth rates.