Development of a tethered, high-altitude, rigid-wing platform

grantor: University of TorontoA tethered, high-altitude, rigid-wing, platform (scTHARWP) was studied as a possible improvement over the helium-filled, tethered aerostats currently in use for positioning payloads at a specified altitude. The possible gains associated with implementing the scTHARWP were increased operating altitude, improved positioning accuracy, and reduced operating cost. An equilibrium analysis was developed to evaluate the trim-state and the feasibility of the scTHARWP. The scTHARWP was composed of a tether and a flight vehicle. In most research of previous tethered systems, the dynamic motions of the tether were neglected or minimally accounted for in the formulation of the dynamic stability analysis. Unlike these previous analyses, the scTHARWP stability analysis was based on a discrete-element tether model which allowed the evaluation of the tether motion and its interaction with the flight vehicle motion. The scTHARWP design was then optimized for the maximum trim-state altitude as well as the most stable dynamic response. Although the optimized scTHARWP was naturally stable, its stability characteristics were further enhanced by the inclusion of control gains which defined the behaviour of the scTHARWP'S control system. Finally, the implementation of the control system was discussed along with recommendations for how to improve upon the final control system.M.A.Sc