Integration of Low-Cost IMU with MEMS and NavIC/IRNSS Receiver for Land Vehicle Navigation

Global Navigation Satellite System (GNSS) based navigation is ubiquitous for land vehicles to any known or unknown location. Location coordinates of the land vehicles are obtained with GNSS and maps for choosing the route and guidance for driving. Similarly, in near future driver-less cars are expected to enter into the market. For this purpose only GNSS is not sufficient for navigation, the best complementary system for GNSS is Inertial Navigation System (INS). In this paper, we proposed the loosely coupled integration of low cost Micro Electro Mechanical Systems (MEMS) based Inertial Measurement Unit (IMU) with NavIC (Navigation with Indian Constellation). As the NavIC is a regional navigational satellite system, it can be used only in India and surroundings. Low-cost MEMS based IMU BMI160 and a NavIC enabled receiver is used to evaluate the performance of the loosely coupled integrated navigation solution. The calibration of the IMU is done using Allan variance with stationary data. Generally, low cost IMU is calibrated or updated using GNSS measurements. However, in the absence of GNSS and the vehicle is stationary, IMU is calibrated and updated using Zero Velocity Update (ZVU) method. In this paper, the performance of loosely coupled integration of IMU with GNSS is analysed in three different modes with NavIC, GPS and NavIC+GPS in the urban scenario, mainly in terms of outage period and the statistical accuracy measures within the outages. The experimental results shows that integration of low-cost IMU with NavIC+GPS outperforms the integration with NavIC and GPS separately.