Trajectory Optimization for Underwater Gliders Considering Depth Constraints Yoon, Sukmin; Kim, Jinwhan;
In this study, the problem of trajectory optimization for underwater gliders considering depth constraints is discussed. Typically, underwater gliders are controlled to dive and climb in a saw-tooth pattern at constant gliding angles. This approach is effective and close to optimal for deep water applications. However, the optimal path deviates from the saw-tooth path in shallow water conditions. This study focuses on finding more efficient gliding paths that can minimize the traverse time in the horizontal plane when the water depth is limited. The trajectory optimization problem is formulated into a minimum time control problem with inequality path constraints and hydrodynamic drag effects. A numerical approach based on the pseudo-spectral method is adopted as a solution approach, and the simulation results are presented.
Unmanned underwater vehicle;Trajectory optimization;Two-point boundary value problem;
Bryson, A.E., Ho, Yu-Chi, 1975. Applied Optimal Control: Optimization, Estimation and Control. Revised Edition, Hemisphere Publishing Corporation, USA.
Ericksen, C.C., Osse, T.J., Light, R.D., Timothy, W., Lehman, T.W., Sabin, P.L., Ballard, J.W., Chiodi, A.M., 2001. Seaglider: A Long-Range Autonomous Underwater Vehicle for Oceanographic Research. Journal of Oceanic Engineering, 26(4), 424-436.
Garau, B., Bonet, M., Alvarez, A., Ruiz, S., Pascual, A., 2009. Path Planning for Autonomous Underwater Vehicles in Realistic Oceanic Current Fields: Application To Glider In The Western Mediterranean Sea. Journal of Maritime Resarch, 4(2), 5-22.
Graver, J.G., Bachmayer, R., Leonard, N.E., Fratantoni, D.M., 2001. Underwater Glider Dynamics and Control. Proceedings of 12th International Symposium on Unmanned Untethered Submersible Technology(UUST). Durham UK, 1710-1742.
Isern-Gonzalez, J., Hernandez-Sosa, D., Fernandez-Perdomo, E., Cabrera-Gamez, J., Dominguez-Brito, A.C., Prieto-Maranon, V., 2011. Path Planning for Underwater Gliders Using Iterative Optimization. Proceedings of Robotics and Automation, Shanghai China, 1538-1543.
Lewis, F.L., Vrabie, D.L., Syrmos V.L. , 2012. Optimal Control. 3rd Edition, John Wiley & Sons, Inc., New Jersey.
Mertens, S., Mingramm, S., 2008. Brachistochrone with Loose Ends. European Journal of Physics, 29(6), 1119-1129.
Sherman, J., Davis, R.E., Owens, W.B., Valdes, J., 2001. The Autonomous Underwater Glider "Spray". Journal of Oceanic Engineering, 26(4), 437-446.
Smith, R.N., Yi, Chao, Li, Peggy P., Caron, D.A,, Jones, B.H., Sukhatme, G.S., 2010. Planning and Implementing Trajectories for Autonomous Underwater Vehicles to Track Evolving Ocean Precesses Based on Predictions from a Regional Ocean Model. Journal of The International Journal of Robotics Research, 29(12), 1475-1497.
Yoon, S.M., Kim, J.W., 2013. System Design and Path Optimization of a Shallow-water Underwater Glider. Proceedings of the Annual Autumn Meeting the Korea Society of Ocean Engineers, Seoul Korea, 34-37.