| Abstract: | The states depicted by system equation of SINS initial alignment are driven by system stochastic noise. The system stochastic noise acts on system states by observation noise matrix. The observation noise matrix is an identical matrix in common system equation. But the assumption that the observation noise matrix is an identical matrix is conditional. The condition is given by deduction. If horizontal accelerometers or horizontal gyros noises are not equal, there will be state estimation errors when the simple system state equation is utilized. The single-axial rotation multi-position alignment simulation is carried out to validate the conclusion. The simulation results show if horizontal gyros noises are not equal, there will be state estimation errors when the simple system equation is utilized. |
