BDS/IMU Integrated Auto-Navigation System of Orchard Spraying Robot

To improve the accuracy and reliability of orchard spraying robots, an integrated navigation system was developed, consisting a real-time kinematic positioning-Beidou satellite (RTK-BDS) receiver, inertial measurement unit (IMU), controller, servo motors. Using loose coupling combination method, error Kalman filter algorithm based on position heading angle is implemented to correct in real time. Combining kinematics model pure pursuit robot, path-tracking control proposed. Path planning conducted according terrain characteristics orchards. Field experiments were carried out robot evaluate proposed auto-navigation system. The results showed that when static, positioning performances BDS alone BDS/IMU combined similar, less than 1.5 cm, errors within 0.3°; moving straight line at speed 0.4 m/s, only using 5.29 3°, while 2.49 2°. significantly improved. When maximum offset lower 10.77 average not higher 3.55 root mean square (RMSE) lateral deviation 1.19 cm. could make track pre-set path smoothly stably.