Design of a Rule-Based Tuned PID Controller for Tether Management of a Suspended Tethered UAV
Abdul Hakim C. Abantas, Winston A. Sabellona, Carl John O. Salaan · 2022
Unmanned Aerial Vehicles (UAVs) have become more popular in recent years for various uses. Despite their popularity, UAVs have one major disadvantage: a short flight time. This is undesirable for critical applications that require prolonged periods of UAV operation. Recent research has found a solution, and that is to use a tether to connect the UAV to a ground station that supplies power.Recent innovations have led to the development of the suspended or hanging tethered UAV, where the tether source is located above the UAV rather than below. This setup is useful for situations where a high, elevated area is more accessible than the base area of the point of interest. The use of tether cables, however, also presents one problem, which is a drag. Too much tension or slack on the cable can impede the flight of the UAV, and the cable might also get entangled with the spinning rotors. Therefore, a fast and responsive tether-cable management controller must be devised as a solution.This study focuses on developing a PID-based controller for the tether management system of a suspended tether-powered drone. This study employs a modified Ziegler-Nichols’ rule-based tuning method to identify the potential gains of Kp and Kd. The study utilizes a heuristic approach to determine the optimum Ki value. Several tests were conducted to determine the appropriate PID gains. Finally, the performance of the PID-based controller was verified through an actual flight test.