5.1.2. Experimental Scenes

Since the residual chi-square test is widely used to detect faults in the positioning domain and the traditional EKF is the most commonly used GNSS/INS integrated navigation algorithm, the proposed algorithm was compared with the EKF to verify its performance. Two experiments were carried out in typical urban canyons in Beijing. The scenarios are shown in Figure 5a,b, representing mid and deep urban canyons, respectively. We first tested the situation in which the vehicle went through the narrow viaduct and the GNSS signals were slightly affected for a short time, as shown in Figure 5a. Then, we carried out

another experiment in which the vehicle went through a wide floor hole, and the GNSS signals were seriously affected for a long time, as shown in Figure 5b.

**Figure 5.** The experimental scenes of cases 1 and 2. (**a**) Case 1: The GNSS was slightly affected when the vehicle passed the narrow viaduct. (**b**) Case 2: The GNSS was seriously affected when the vehicle passed the wide floor hole.
