Proportional-Integral-Plus (PIP) Gain Scheduling Control of an Intelligent Excavator

This paper considers the design and implementation of an electro-hydraulic control system for a robotic excavator, namely the Lancaster University Computerised and Intelligent Excavator (LUCIE). The excavator is being developed to autonomously dig trenches without human intervention. Here, a gain scheduling design, based on Proportional-Integral-Plus (PIP) control methods, is utilised to regulate the highly nonlinear joint dynamics. Simulation and initial field tests both demonstrate the feasibility of the proposed technique, with the excavator arm directed along specified trajectories in a smooth, fast and accurate manner.