Experimental investigation into the basic application of force and position control for human-machine team lifting operations in manufacturing

Abstract

In manual material handling operations associated with manufacturing, often a two-person team lifts a container. The labor intensive task of lifting a container could be improved by replacing the two-person team with a human-machine team. It is hypothesized that a human-machine team could behave similarly to a two-person team when lifting a container. To test this hypothesis, the presented research experimentally investigated the application of force and position control to a machine that was working collaboratively with a human to lift a constructed container. A basic experimental approach to lifting and control was undertaken at a benchtop scale to evaluate the results for proof-of-concept and further development. For the experimental setup presented, the results show that a combined force and position control architecture delivered better lifting performance as compared to standalone force or position control. It was concluded that the combined force and position control strategy created better team behavior for the machine as it worked collaboratively with the human to lift a constructed container. The advantage of the control approach presented is its simplicity and its ability to be retrofitted to existing equipment. The novelty of the control approach lies within the way the force and position errors from independent controllers are combined into a single command signal with no priority given to either force or position.