Optimal UAS Path Planning for Convoy Overwatch
Riley A. Livermore, Richard G. Cobb · 2015
The optimal path to fly a small unmanned aerial system (SUAS) for convoy overwatch is determined. The optimal path is approximated and demonstrated onboard a SUAS in hardware in-the-loop simulations and flight test. The optimization algorithm minimizes a cost function consisting of the SUAS control effort and deviation from a desired slant range. Due to several hardware and software limitations, the SUAS autopilot is currently incapable from implementing the optimal controller onboard. Therefore, a heuristic-based algorithm is developed through a series of three iterative steps and implemented onboard the autopilot to approximate the optimal solution. The first step manipulates the autopilot loiter logic to allow target tracking. The second step identifies three parameters in the loiter logic that are tuned using a Design of Experiments (DOE) methodology. Lastly, a finite state machine (FSM) is created based on the DOE results to further optimize the real-world convoy overwatch algorithm. Each iteration is flight tested to evaluate how well they approximate the optimal path. The final algorithm using the FSM exhibits a 65% improvement in tracking performance and demonstrates an implementable, near-optimal convoy overwatch algorithm.