Systems Engineering of Agricultural Robot Design

The design of an agricultural robot is a complex task since in addition to the many closely related design parameters that must be determined, the design is highly affected by crop parameters which are uncertain and loosely structured. This paper presents a systems engineering method to evaluate the performance of an agricultural robot by Simulating and comparing different types of robots, number of arms, multiple arm configurations, workspace design and dynamic characteristics. Numerical simulation tools were developed to quantify measures of machine performance such as cycle time and percentage of successful cycles based on an extensive statistical analysis using measured fruit locations and simulated crop parameters. The methodology developed was applied to determine design parameters for a robotic melon harvester. Simulation results indicated that the cartesian robot was faster than the cylindrical robot for the melon harvesting task. Activating two arms in tandem was the fastest configuration evaluated. Simulation provided an important tool for evaluating the multitude of design and crop parameters and for comparing alternatives in a timely manner prior to prototype construction. Through systems engineering design parameters and preferable crop conditions were recommended based on which a prototype robotic melon harvester has been constructed.