Marine vessel control using the tiller-motor system.

Operator performance on the tiller-motor system was investigated in a field survey and in a tracking simulator. Boat operators in Study 1 reported both control difficulties and discomfort, when using their tiller-motor system. Participants in Study 2 operated a tiller-motor simulator of a boat navigating a river over a 20 min period. Directional and speed control performance was found to be poor, particularly on the first trials and under emergency conditions. These results support the suggestion that the incompatible nature of the control/response relationship in tiller-motor systems can cause operator difficulties. The dimensions of the simulator were systematically varied and found to influence operator shoulder extension, and ratings of exertion and discomfort. Recommendations for tiller-motor system design and installation are offered.