Vehicle GPS locator requires inertial navigation for supplementary backup

When driving in urban canyons, tunnels, or under bridges, the signal reception of on-board GPS locators may deteriorate. Even worse, it may suffer a complete interruption. Therefore, we need a supplementary or standby system, such as Inertial navigation system.

However, this efficiency cannot be maintained during a long interruption of the vehicle GPS locator, especially for low-cost and commercial inertial sensors of the Inertial navigation system. This disadvantage is mainly because the Inertial navigation system solution will suffer from cumulative error growth over time. This error can cause path or trajectory drift, which becomes very serious in the long run.

The integration between the Inertial navigation system and the system based on the vehicle GPS locator provides a more powerful solution than each system alone. In particular, the integration of Inertial navigation system and vehicle GPS locator requires the two systems to provide accurate solutions for vehicles.

However, when the vehicle is in a challenging environment, the on-board GPS locator receiver cannot successfully update the integrated filter, so the Inertial navigation system becomes the only source of solutions. In some extreme cases, when the interruption time of the on-board GPS locator is prolonged, the quality of the solution will decline rapidlydue to the drift of the Inertial navigation system.