Planning the sequence of tasks for harvesting robots

A methodology for planning the sequence of tasks for a harvesting robot is presented. The fruit targets are situated at unknown locations and must be detected by the robot through a sequence of sensing tasks. Once the targets are detected, the robot must execute a harvest action at each target location. The traveling salesman paradigm (TSP) is used to plan the sequence of sensing and harvesting tasks taking into account the costs of the sensing and harvesting actions and the traveling times. Sensing is planned online. The methodology is validated and evaluated in both laboratory and greenhouse conditions for a case study of a sweet pepper harvesting robot. The results indicate that planning the sequence of tasks for a sweet pepper harvesting robot results in 12% cost reduction. Incorporating the sensing operation in the planning sequence for fruit harvesting is a new approach in fruit harvesting robots and is important for cycle time reduction. Furthermore, the sequence is re-planned as sensory information becomes available and the costs of these new sensing operations are also considered in the planning.