Coordinated standoff target tracking using two UAVs with only bearing measurement

A novel method for a random moving target coordinated standoff tracking was proposed to maximize the target position estimation precision by two unmanned aerial vehicles (UAVs) equipped with only bearing sensor. The analytical relationship model between the UAV observation geometry configuration and the root mean square error (RMSE) of target position estimation, which is chosen as performance index, was established, and thus the optimal UAV observation geometry configuration was obtained. Extended information filter was used to implement target states fusion and estimation. The optimal cooperative observation geometry configuration was implemented using online distributed nonlinear model predictive control (NMPC), considering the constraints of UAV platform dynamic performances, collision avoiding, and security distance. The simulation results demonstrated the pair of UAV effectively maintained the optimal observation geometry configuration and coordinated standoff target tracking performance in real-time.