Research on Indoor and Outdoor Integrated Navigation Method Based on Improved Residual Chi Square Detection

Aiming at the problems that the sudden change of sensor availability in indoor and outdoor multi-source integrated navigation during indoor and outdoor environment switching is easy to cause positioning jump, and the traditional residual detection method is not sensitive to gradual change GNSS offset, resulting in mode switching delay or false triggering, a method of indoor and outdoor integrated navigation based on improved residual chi square detection is proposed. This method decouples the residuals in the horizontal and vertical directions, and adopts the dynamic detection threshold related to the carrier speed in both directions, taking into account the characteristics of error changes in both directions and reducing the impact of carrier motion on the residuals; When the GNSS signal is recovered, the gradual recovery strategy is used to avoid the system position jump. In order to verify the effectiveness of the proposed method, a simulation experiment environment is built for simulation experiments. Simulation results show that the positioning accuracy of the proposed method is improved by more than 26% compared with the traditional residual chi square detection method, and the robustness of the system is effectively improved.