Swing Trajectory Control for Large Excavators

There is a strong push within the mining sector to automate equipment such as large excavators. A challenging problem is the control of motion on high inertia degrees of freedom where the actuators are constrained in the power they can deliver to and extract from the system and the machine’s underlying control system sits between the automation system and the actuators. The swing motion of an electric mining shovel is a good example. This paper investigates the use of predictive models to achieve minimum time swing motions in order to address the question what level of performance is possible in terms of realizing minimum time motions and accurate positional control. Experiments are described that explore these questions. The work described is associated with a project to automate an electric mining shovel and whilst the control law discussed here is a much simplified form of that used in this work, the experimental study sheds considerable light on the problem.