TF/TA optimal Flight trajectory planning using a novel regenerative flattener mapping method

Document Type : Article

Authors

Aerospace Group, Faculty of New Sciences and Technologies, University of Tehran, Tehran, Iran

Abstract

In this paper, a new methodology has been proposed to enhance the conformal mapping applications in the process of optimum trajectory planning in Terrain Following (TF) and Terrain Avoidance (TA) Flights. The new approach uses the conformal mapping concept as a flattener tool to transform the constrained trajectory-planning problem with flight altitude restrictions due to the presence of obstacles into a regenerated problem with no obstacle and minimal height constraints. In this regard, the Schwarz–Christoffel theorem has been utilized to incorporate the height constraints into the aircraft dynamic equations of motion. The regenerated optimal control problem then is solved employing a numerical method namely the direct Legendre-Gauss-Radau pseudospectral algorithm. A composite performance index of flight time, terrain masking, and aerodynamic control effort is optimized. Furthermore, to obtain realistic trajectories, the aircraft maximum climb and descent rates are imposed as inequality constraints in the solution algorithm. Several case studies for two-dimensional flight scenarios show the applicability of this approach in TF/TA trajectory-planning. Extensive simulations confirm the efficiency of the proposed approach and verify the feasibility of solutions satisfying all of the constraints underlying the problem

Keywords

Main Subjects


References:
1. International Civil Aviation Organization, Safety Report. A Coordinated, Risk-based Approach to Improving Global Aviation Safety, Montreal, Canada (2014).
2. Nonami, K., Kendoul, F., Suzuki, S., Wang, W., and Nakazawa, D. "Introduction", In Autonomous Flying Robots, pp. 1-29, Springer, Tokyo, Japan (2010).
3. Shiller, Z. "Off-line and on-line trajectory planning", In Motion and Operation Planning of Robotic Systems, G. Carbone and F. Gomez-Barvopp, Eds., pp. 29-62, Springer, New York (2015).
4. Kirk, D.E. "The variational approach to optimal control problems", In Optimal Control Theory: An Introduction, Dover Publication Inc., New York (2004).
5. Yang, H. and Zhao, Y. "Trajectory planning for autonomous aerospace vehicles amid known obstacles and conflicts", Journal of Guidance, Control, and Dynamics, 27(6), pp. 997-1008 (2004).
6. Vachtsevanos, G., Tang, L., Drozeski, G., and Gutierrez, L. "From mission planning to flight control of unmanned aerial vehicles: Strategies and implementation tools", Annual Reviews in Control, 29(1), pp. 101-115 (2005).
7. Karelahti, J., Virtanen, K., and  Ostrom, J. "Automated generation of realistic near-optimal aircraft trajectories", Journal of Guidance, Control, and Dynamics, 31(3), pp. 674-688 (2008).
8. Lee, S., Cho, A., and Kee, C. "Integrated waypoint path generation and following of an unmanned aerial vehicle", Aircraft Engineering and Aerospace Technology, 82(5), pp. 296-304 (2010).
9. Babaei, A.R. and Mortazavi, M. "Fast trajectory planning based on in-flight waypoints for unmanned aerial vehicles", Aircraft Engineering and Aerospace Technology, 82(2), pp. 107-115 (2010).
10. Lin, Z., Castano, L., and Xu, H. "A fast obstacle collision avoidance algorithm for fixed wing UAS", 2018 International Conference on Unmanned Aircraft Systems (ICUAS), Tokyo, Japan, pp. 559-568 (2018).
11. Naidu, D.S. "Constrained optimal control systems", In Optimal Control Systems, CRC Press LLC, Washington, D.C, pp. 293-361 (2003).
12. Menon, P.K.A., Cheng, V.H.L., and Kim, E. "Optimal trajectory synthesis for terrain-following  flight", Journal of Guidance, Control, and Dynamics, 14(4), pp. 807-813 (1991).
13. Malaek, S.M. and Kosari, A. "Dynamic based cost functions for TF/TA flights", IEEE Transactions on Aerospace and Electronic Systems, 48(1), pp. 44-63 (2012).
14. Malaek, S.M. and Kosari, A. "Novel minimum time trajectory planning in terrain following flights", IEEE Transactions on Aerospace and Electronic Systems, 43(1), pp. 2-12 (2007).
15. Kosari, A. and Kassaei, S.I. "Dynamic constrained low altitude flight maneuvers with constant energy", 2017 IEEE International Conference on Power, Control, Signals and Instrumentation Engineering (ICPCSI), India, pp. 3085-3089 (2017).
16. Denton, J.E. and Jones, R.V. "A new technique for terrain following/terrain avoidance guidance command generation", 40th AGARD Guidance and Control Symposium, New York (1985).
17. Jalali-Naini, S.H. and Sajjadi, S.H. "First-order optimal line-of-sight guidance for stationary Targets", Scientia Iranica, 23(2), pp. 588-599 (2016).
18. Kosari, A. Maghsoudi, H., and Lavaei, A. "Path generation for  flying robots in mountainous regions", International Journal of Micro Air Vehicles, 9(1), pp. 44-60 (2017).
19. Williams, P. "Three-dimensional aircraft terrainfollowing via real-time optimal control", Journal of Guidance, Control, and Dynamics, 30(4), pp. 1201- 1206 (2007).
20. Kamyar, R. and Taheri, E. "Aircraft optimal terrain/threat-based trajectory planning and control", Journal of Guidance, Control, and Dynamics, 37(2), pp. 466-483 (2014).
21. Qing, L. "Aircraft route optimization using genetic algorithms", Second International Conference on Genetic Algorithms in Engineering Systems, Glascow, UK, pp. 394-397 (1997).
22. Nikolos, I.K., Valavanis, K.P., Tsourveloudis, N.C., and Kostaras, A.N. "Evolutionary algorithm based offline/online path planner for uav navigation", IEEE Transactions on Systems, Man and Cybernetics, Part B (Cybernetics), 33(6), pp. 898-912 (2003).
23. Nikolos, I.K. and Tsourvelouds, N.C. "Path planning for cooperating unmanned vehicles over 3-D terrain", Informatics in Control, Automation and Robotics: Selected Papers from the International Conference on Informatics in Control, Automation and Robotics 2007, Berlin, pp. 153-168 (2009).
24. Sun, T.Y., Huo, C.L., Tsai, S.J., and Liu, C.C. "Optimal UAV flight path planning using skeletonization and particle swarm optimizer", 2008 IEEE Congress on Evolutionary Computation (IEEE World Congress on Computational Intelligence), Hong Kong, Chin, pp. 1183-1188 (2008).
25. Karimi, J. and Pourtakdoust, S.H. "Optimal maneuver-based motion planning over terrain and threats using a dynamic hybrid PSO algorithm", Aerospace Science and Technology, 26(1), pp. 60-71 (2013).
26. Nobahari, H. and Arab Kermani, M. "Integrated optimization of guidance and control parameters in a dual spin  flying vehicle", Scientia Iranica, 24(5), pp. 2473-2489 (2017).
27. Kosari, A., Maghsoudi, H., Lavaei, A., and Ahmadi, R. "Optimal online trajectory generation for a flying robot for terrain following purposes using neural network", Proceedings of the Institution of Mechanical Engineers, Part G: Journal of Aerospace Engineering, 229(6), pp. 1124-1141 (2015).
28. Rahim, M. and Malaek, S.M. "Intelligent operation using terrain following flight in unmanned aerial vehicles", 2007 IEEE Aerospace Conference, Big Sky, MT, USA, pp. 1-8 (2007).
29. Rahim, M. and Malaek, S.M. "Aircraft terrain following flights based on fuzzy logic", Aircraft Engineering and Aerospace Technology, 83(2), pp. 94-104 (2011).
30. Bagherian, M. "Unmanned aerial vehicle terrain following/ terrain avoidance/threat avoidance trajectory planning using fuzzy logic", Journal of Intelligent & Fuzzy Systems, 34(3), pp. 1791-1799 (2018).
31. Vachhani, L., Kumar, P.R., and Seridharan, "Advances in mapless and map-based strategies for robot navigation a review", In Robot Vision: Strategies, Algorithms and Motion Planning, K.D. Ito, Ed., Nova Science Publishers, Inc., New York (2009).
32. Megherbi, D. and Wolovich, W.A. "Real-time velocity feedback obstacle avoidance via complex variables and conformal mapping", Proceedings 1992 IEEE International Conference on Robotics and Automation, Nice, France, pp. 206-213 (1992).
33. Chuang, J.H. and Ahuja, N. "An analytically tractable potential field model of free space and its application in obstacle avoidance", IEEE Transactions on Systems, Man and Cybernetics, Part B (Cybernetics), 28(5), pp. 729-736 (1998).
34. Chen, Y., Luo, G., Mei, Y., Yu, J., and Su, X. "UAV path planning using artificial potential field method updated by optimal control theory", International Journal of Systems Science, 47(6), pp. 1407-1420 (2016).
35. Qu, Y., Zhang, Y., and Zhang, Y. "A global path planning algorithm for fixed-wing UAVs", Journal of Intelligent & Robotic Systems, 91(3), pp. 691-707 (2018).
36. Kosari, A. and Kassaei, S.I. "Using conformal mapping in developing a novel optimal obstacle-avoidance trajectory-planning for a flying robot", 2017 IEEE International Conference on Power, Control, Signals and Instrumentation Engineering (ICPCSI), India, pp. 3080-3084 (2017).
37. Roskam, J. "General equations of motion for rigid airplanes", In Airplane Flight Dynamics and Automatic Flight Controls, pp. 9-46, Roskam Aviation and Engineering Corporation, Lawrence (2001).
38. Brown, J.W. and Churchill R.V. "Conformal mapping", In Complex Variables and Applications, 8th Edn., pp. 355-372, McGraw-Hill, Michigan (2008).
39. Abolwitz, M.J. and Fokas, A.S. "Conformal mappings and applications", In Complex Variables Introduction and Applications, 2nd Edn., pp. 311-408, Cambridge University Press, New York (2003).
40. Driscoll, T.A. and Trefethen, L.N. "Numerical methods", In Schwarz-Christoffel Mapping, pp. 23-39, Cambridge University Press, New York (2003).
41. Faires, J.D. and Burden, R. "Numerical solutions of nonlinear systems of equations", in Numerical Analysis, 9th Edn., pp. 629-669, Brooks/Cole Cengage Learning, New York (2010).
42. Rao, A.V. "Survey of numerical methods for optimal control", Advances in the Astronautical Sciences, 135(1), pp. 497-528 (2009).
43. Betts, J.T. "Survey of numerical methods for trajectory optimization", Journal of Guidance, Control, and Dynamics, 21(2), pp. 193-207 (1998).
44. Huntington, G.T. "Advancement and analysis of a gauss pseudospectral transcription for optimal control problems", PhD Thesis, Department of Aeronautics and Astronautics, Massachusetts Institute of Technology (2007).
45. Garg, D., Patterson, M., Hager, W., Rao, A.V., Benson, D.A., and Huntington, G.T. "A unified framework for the numerical solution of optimal control problems using pseudospectral methods", Automatica, 46(11), pp. 1843-1851 (2010).
46. Garg, D., Hager, W., and Rao, A.V. "Pseudospectral methods for solving infinite-horizon optimal control problems", Automatica, 47(4), pp. 829-837 (2011).
47. Gill, P.E., Murray, W., and Saunders, M.A. "SNOPT: an SQP algorithm for large-scale constrained optimization", SIAM Journal on Optimization, 12(4), pp. 979- 1006 (2002).
48. Khademi, I., Maleki, B., and Nasseri Mood, A. "Optimal three dimensional terrain following/terrain avoidance for aircraft using direct transcription method", 2011 19th Mediterranean Conference on Control & Automation (MED), Corfu, Greece, pp. 254-258 (2011).