Optimized Anchor Node Selection Algorithm Considering Power and Accuracy for Indoor Integrated Navigation System Based on INS/UWB

This paper introduces an indoor integrated navigation system for the auto-control of unmanned aerial vehicle (UAV) and robot that fuses inertial sensors and ultra wide band (UWB) networks. In this paper, we concentration on the problem of selecting the optimized UWB anchor node to obtain the distance measurement between the selected anchor node and the tag node for this indoor integrated navigation system. Taking the navigation accuracy and system power consumption into account according to the requirements and features of UWB system, we propose and analyze the performance of four kinds of anchor node selection algorithms, named alternation algorithm, power-first algorithm, accuracy-first algorithm and the optimized algorithm considering power and accuracy. In the fourth algorithm, we introduce dynamic local dilution of precision (DOP) values which reflect the impact of the geometric distribution of anchor nodes to guarantee precision and define a cost function of DOP values and UWB communication distance for a complementary consideration of power consumption. To fuse the inertial sensor data and the selected UWB distance measurement, an extended Kalman filter (EKF) is applied in this integrated system to correct the state errors. Simulations and experiments with low-cost Micro-electromechanical inertial sensors and Decawave UWB transceivers have been done to evaluate the performance of these four anchor node selection algorithms. The simulation and experiments results verify that the fourth algorithm proposed in this paper can achieve a good balance in system multiple demands of navigation accuracy and system power consumption.