Optimal motion planning of a mobile conveying Cartesian manipulator for maximum melon harvesting.

This paper describes a two step procedure to calculate the trajectory of a melon harvesting Cartesian mobile manipulator that results in the maximum number of melons harvested. The goal of the first step is to calculate the minimum-time trajectory required to traverse between any two melons while adhering to velocity, acceleration, location, and endpoint constraints. This is accomplished in a hierarchal manner by solving several sub problems involving optimal control and nonconvex optimization, enabling maximum melon harvesting to be formulated as the orienteering problem with time windows. In the second step, the orienteering problem is solved using the moving branch and prune method, based on dynamic programming. This allows sub-optimal sequences of melons to be eliminated on the fly without the need to solve the entire problem at once, enabling online implementation. An example is shown to demonstrate the efficacy of the algorithm.