Development of a Remote Control System for Autonomous Agricultural Vehicles

This paper presents a method to develop a system, which will enable an autonomous agricultural vehicle to follow a leading vehicle with a given lateral and longitudinal offset. With the aid of the RTK GPS systems the position of the leading tractor was obtained every 500 ms with accuracy in the range of centimeters. To provide the target position for the guidance of the following agricultural vehicle, the position information of the leading vehicle was transmitted by wireless modems to the following vehicle continuously. With the method of curve fitting a desired path for the following vehicle could be dynamically created. Based on the target position and the generated path the desired speed and the desired steering angle of the following tractor are calculated. In order to ensure the precise navigation of the driverless following tractor, a course tracking controller and a speed controller were designed and implemented. Wireless communication was used to transmit process data and operation commands between the agricultural vehicles and a data protocol was developed to make the vehicles working collaboratively. In addition to the motion control algorithms which could keep the autonomous agricultural vehicle following the leading tractor, considerations about safety and robustness of the whole platooning control system will also be issued in this paper. The whole research work is supported by the Federal Ministry of Food, Agriculture and Consumer Protection of the German Government.