Enhancing a RNAV guidance system for UAS with fly over waypoints and track to a fix path terminators

Abstract

The ICARUS research group is developing an UAS (Unmanned Aerial System) architecture so as to take advantage of them in civil applications, such as fire detection. Such architecture is based on different services, which include the flight service. The flight service is responsible for flying the UAS according to a flight plan. The aim of this project is to emulate a control loop so as to enable the UAS on-board autopilot perform FO+TF (Fly Over + Track to a Fix) transitions, taking into account RNAV legs and WPs (Waypoints). Regarding this autopilot capability, then new WPs are computed to deceive this autopilot so as to fly other types of WPs and transitions such as FO+DF (Fly Over + Direct to a Fix), FO+RF (Fly Over + Radius to a Fix) and FB+TF (Fly by + Track to a Fix). The work has been divided in four main blocks. Firstly, there is a brief introduction to the ICARUS UAS Architecture and the basic RNAV parameters. Next, the second block defines the main characteristics of the FO+TF control loop. Next to that, by using several equations, the position of otherWPs is defined, in order to fly other types of transitions. The third chapter includes the implementation of the first two chapters in the code. Finally, the experimental part includes the testing with the aid of FGFS (Flight Gear Flight Simulator) and Google Earth. One of the main limitations of our system is the effect of wind and that is referred in the last sections of this project. It is important to understand the limitations and to be aware of them. However, the result of the project is completely satisfying.