Ph.D. Student, Queen's University
Maintain a good Navigation Solution in GNSS Challenging Environments
GPS is the primary source of navigation solution for both Autonomous and Land Vehicles. Unfortunately, GPS receivers can't provide a reliable solution without having a line of sight (LOS) connection with at least four satellites. Moreover, in some environments such as urban canyons, Tunnels, and underwater the LOS can't be achieved because of low signal strength, Multipath, or blockage due to high rising buildings in such environments. Therefore, alternative source of navigation solution is required to provide the user with the demanded information. Inertial Sensor Systems as the RISS or the INS which are depending on measuring the vehicle situation from accelerations and rotation rates and immune to the radio signals perturbations. In spite of these advantages, these systems are suffering from error drift over time. Another solution should take place and provide a reliable and continuous navigation solution. Many approaches were investigated to deal with such situations. Among these approaches, utilizing the fact that the land vehicles don't fly so adjusting the heading should reflect on the overall solution because obtaining velocity and position vectors depends on the heading angle measuring. Starting from this fact, a calibrated magnetometers with fluxgate shield should help in getting a good solution enhancing the overall system especially when the GPS Signals blocked.