Energy-Based Long-Range Path Planning for Soaring-Capable Unmanned Aerial Vehicles

To enable long-distance, long-duration flights by small soaring-capable uninhabited aircraft, a graph-based method for planning energy-efficient trajectories over a set of waypoints is presented. It introduces the energy map, which is an upper bound on the minimum energy required to reach a goal from anywhere in the environment while accounting for arbitrary three-dimensional wind fields. The energy map provides the path to the goal as a sequence of waypoints, the optimal speeds to fly for each segment between waypoints, and the heading required to fly along a segment. Trajectories computed using the energy map are compared with trajectories planned using an A * -based approach. Results are presented for simple wind fields representative of orographic lift. Finally a high-fidelity numerical simulation of a realistic wind field (ridge lift and wave over complex terrain) is used as a test case. The energy-map approach is shown to perform very well without the need for the heuristics associated with A * .

[1]  J. Hedrick,et al.  Optimal Flight Paths for Soaring Flight , 1975 .

[2]  Michael J. Allen Guidance and Control of an Autonomous Soaring Vehicle with Flight Test Results , 2007 .

[3]  Yiyuan Zhao,et al.  Optimal patterns of glider dynamic soaring , 2004 .

[4]  Paul B. MacCready,et al.  REGENERATIVE BATTERY-AUGMENTED SOARING , 1999 .

[5]  G. Sachs,et al.  SHEAR WIND STRENGTH REQUIRED FOR DYNAMIC SOARING AT RIDGES , 2001 .

[6]  David A. Anisi,et al.  On-line Trajectory planning for aerial vehicles : a safe approach with guaranteed task completion , 2006 .

[7]  J. L. de Jong The "Convex-Combination Approach": a Geometric Approach to the Optimization of Sailplane Trajectories , 1984 .

[8]  R. Davis,et al.  The autonomous underwater glider "Spray" , 2001 .

[9]  Michael Morrow,et al.  A Self-Sustaining, Boundary-Layer-Adapted System for Terrain Exploration and Environmental Sampling , 2005 .

[10]  D. C. Webb,et al.  SLOCUM: an underwater glider propelled by environmental energy , 2001 .

[11]  Daniel J. Edwards Implementation Details and Flight Test Results of an Autonomous Soaring Controller , 2008 .

[12]  John H. Cochrane,et al.  MacCREADY THEORY WITH UNCERTAIN LIFT AND LIMITED ALTITUDE , 1999 .

[13]  C. C. Eriksen,et al.  Seaglider: a long-range autonomous underwater vehicle for oceanographic research , 2001 .

[14]  G. J. Sander,et al.  On Global Optimal Sailplane Flight Strategy , 1979 .

[15]  Steven M. LaValle,et al.  Planning algorithms , 2006 .

[16]  Arthur E. Bryson,et al.  Neighboring Optimal Aircraft Guidance in Winds , 2001 .

[17]  J.W. Langelaan Tree-based trajectory planning to exploit atmospheric energy , 2008, 2008 American Control Conference.

[18]  Anthony Stentz,et al.  The Focussed D* Algorithm for Real-Time Replanning , 1995, IJCAI.