Experimental comparison of nonlinear guidance laws for unmanned aircraft

Two aircraft guidance algorithms from the literature, the Non-Linear Guidance Law (NLGL) and the Nonlinear Differential Geometric Path-Following Guidance Law (NDGPFG), are assessed using a 25 kg unmanned aerobatic aircraft. The paper provides experimental results of the first flight test with the NDGPF. Prior to the real world application, a simulation study is performed to mitigate the risk. For both guidance laws, tracking performance is investigated on a purely kinematic model with unlimited control bandwidth first. Both laws provide superb tracking and the NDGPFG achieves exact path-following, i.,e. zero track error. In a second simulation, a high-fidelity model of the aircraft is used. This model includes parasitic dynamics and hence has a finite control bandwidth. In contrast to the results with the purely kinematic model, neither of the algorithms achieves exact path-following with the high-fidelity model. Nevertheless, both guidance laws provide good tracking performance and prove feasible in varying environmental conditions. This observation is finally confirmed in the flight test experiment.
Subjects
control of vehicles
navigation
guidance
flight control
aircraft control
nonlinear control
guidance systems
control application
experimental validation
DDC Class
620: Engineering
600: Technology