Manual control of crane systems

Two independent studies have been made into the man-machine systems aspects of crane control. The studies have been concerned with the analysis of a hoist operation as part of a metal-processing plant group task and the modelling of a crane operator as an element in an electric overhead travelling crane system. The unification of the results of these studies gives a comprehensive view of a crane operator's ability to control a crane system manually. The crane operator, as a complex and versatile information processor and feedback controller, utilizes aids and cues from many sources to enable him to perform his task in a skilful manner. It is suggested that the development of skill in an operator is akin to the progression in servo mechanism theory from compensatory tracking to pursuit tracking and then finally to open-loop tracking. At the pursuit tracking stage of development, the crane operator is considered to operate with a self-adaptive strategy which includes the identification of optimum switching ...