SUMMARY

A helicopter can be used as a flying crane by hanging a load from cables attached to the helicopter. The flying crane is extremely versatile -- it can carry water to put out forest fires, install transmission towers in remote locations, and deliver supplies to stranded ships and offshore oil rigs. Tasks such as these are often too expensive, too slow, or physically impossible to perform with other types of vehicles. Unfortunately, the suspended load swings, which hinders load placement and can significantly degrade control of the helicopter.

This thesis investigates the use of a command-filtering technique (input shaping) to reduce the swing of helicopter suspended loads. Human operator experiments are used to test the manual control of lightly-damped flexible systems, and to study the effects of adding input shaping to the system. In addition, horizontal-load-repositioning tasks are performed using simulated and experimental helicopters, both with and without input shaping. Performance is quantified by task completion time and residual load swing.

Using these analyses, the best conventional input shapers for the helicopter-load system will be identified, and methods for designing input shapers that maximize performance of a human-controlled flexible system will be proposed.