Control of Crane Payloads That Bounce During Hoisting

Crane payloads exhibit unwanted motions such as swings, twists, and bounces that cause safety hazards and decrease performance. Numerous controllers have been developed to reduce payload swing. However, much less consideration has been given to bouncing in the vertical direction, which in some cases can also excite pitching of the payload. This dynamic effect most often arises when the payload is heavy and the suspension cables are long. This brief presents a mathematical model of a bouncing crane payload. Then, a method for generating commands to suppress the oscillations is developed and evaluated. Experiments on a tower crane demonstrate the improved performance provided by the proposed control method.