CAN-based distributed control for autonomous vehicles

Through the work of researchers and the development of commercially available products, automated guidance has become a viable option for agricultural producers. One limiting factor of many commercially available technologies is that they only automate one function of an agricultural vehicle and that their control systems are proprietary to a single machine model. The objective of this project was to evaluate a controller area network (CAN bus) as the basis of an automated agricultural vehicle. The prototype system utilized several microcontroller-driven nodes to act as control points along a system wide CAN bus. Messages were transferred to the steering, transmission, and hitch control nodes from a task computer. The task computer utilized global positioning system data to determine the appropriate control commands. Infield testing demonstrated that each of the control nodes could be controlled simultaneously over the CAN bus. Results showed that the task computer adequately applied a feedback control model to the system and achieved guidance accuracy levels well within the desired range. Testing also demonstrated the system's ability to complete normal field operations such as headland turning and implement control.