Autonomous Parallel Travelling of a Robot Tractor for Automatic Harvesting and Unloading of an Onion Harvester

This paper proposes an autonomous parallel travelling system for an onion harvester and a tractor. Path following control via sliding mode control is applied to each vehicle. The velocity of the tractor is also controlled using the velocity and position of the onion harvester to maintain their relative position. As the result of experiments, the lateral, longitudinal and orientation errors between the tractor and the onion harvester were less than 0.07 m, 0.11 m and 2◦, respectively. It was sufficient for the actual onion harvesting.