2. Model of Launch Vehicle Dynamics and Redundant Strapdown IMUs

The design of control system is based on the dynamics equations and motion equation of the controlled object. The launch vehicle is taken as the controlled object in this section. First, the coordinate system was defined, the force acting on the launch vehicle was analyzed, the motion equation was established, and then its dynamics was analyzed to provide the basis for trajectory re-planning. The zero error, installation error and scale factor error were considered in establishing of the combined error model and the digital pulse output model of redundant strapdown IMUs. The noise model of single-meter gyro was analyzed. The information reliability model is established in view of common outliers in the information. Finally, the number of reconfigurable units and the minimum included angle are proposed as intuitive reference indicators for evaluating the performance of system after failure.