Publications / 1989 Proceedings of the 6th ISARC, San Francisco, USA
The geometric configuration of construction tower cranes - with well defined joints and degrees of freedom - allows to transform them, via robotic technologies, to semi -automatic equipment. We wish to add a fast and accurate navigation option to be used by the operator, mainly for cyclic, routine tasks. We report here on the first completed phase of a project aimed at developing a control system, to be furnished on either existing or newly manufactured cranes. This feasibility study deals with technological, economic and safety aspects of the idea. It identifies major components for a control system, which would be capable to record and play back common paths of the crane hook , as well as automatically navigate between benchmarks at the construction site. The economic evaluation quantifies potential savings in both routine and non - routine tasks, and predicts a minimum of 10-20 percent improvement in the operational efficiency of the crane, and in the productivity of the crews who depend on its services. The safety study highlights typical problems expected from semi-automatic operation of a large crane at a busy construction site, and suggests initial solutions via sensor interaction. The additional safety means should not merely overcome newly created problems, but also enhance the overall safety performance of tower cranes, prevent overloading and reduce maintenance costs. The study concludes with performance specifications for a. basic prototype to be built at the next stages.