Filtering effects on input-shaped command signals for effective crane control

Human operators have difficulty driving cranes quickly, accurately, and safely because of the slow response of heavy crane structures, non-intuitive control interfaces, and payload oscillations. This paper presents a new type of interface that allows operators to drive a crane by moving a hand-held radio-frequency tag. Real-time location sensors are used to track the movements of the tag and the tag position is used in a feedback control loop to drive the crane. An input shaper is added to eliminate dangerous payload oscillations. Unfortunately, significant sensor noise can increase the energy-usage and settling-time during operation. To reduce these negative side effects, several filters are used on experimentally-acquired tag trajectories. The filtered trajectories are then used to drive crane simulations. The filter performance is evaluated with respect to the energy usage of the crane trolley, and the settling time of the crane payload oscillations. The effects of filter window lengths on these parameters are also investigated.