Parallel point-to-point tracking for agricultural Wide-Span Implement Carrier (WSIC)

An automatic guidance and control system for the stationary operating mode of an agricultural Wide-Span Implement Carrier (WSIC) was developed and tested on a robotic experimental platform. Control algorithms for the parallel point-to-point tracking problem (forward point tracking and periodic operation process) were designed. Two robots were instrumented with a dual-rover Real-Time Kinematic Global Positioning System, inertial measurement units, XBee-PRO wireless communication modules, and control processors. The experimental platform executes the control sequence in a master-slave cooperative manner. Results of the single point tracking experiments show that the designed velocity and steering angle control laws can effectively guide the robots from a start point to a target. The average and root-mean-square of the offset errors were less than 0.04 m for both the 2-m and 3-m implement width experiments. The lateral and orientation errors were less than 0.16 m and 11° respectively. The sequential point-to-point tracking experiments confirmed the overall effectiveness of the point tracking control and the master-slave cooperative control. The motions of the master and slave robots were in good synchronization, which can permit high efficiency during autonomous WSIC operations.