Optical Horizontal-Displacement Sensors for Crane Payloads

Sensors made largely of commercially available optical and electronic components are being developed for use in measuring small horizontal displacements of payloads suspended below cranes at the ends of nominally vertical cables. The outputs of these sensors would be used in computer-based automated and manual crane-control systems to guide the horizontal movements of the cranes with respect to the payloads or with respect to nearby objects. For example, in the original intended application, the horizontal displacement would be produced by manually pushing a heavy payload in a desired direction, and the output of an optoelectronic sensor that measured this displacement would be sent to a computer-based crane-control system, which would apply power to move the crane in that direction.