Path planning in uncertain flow fields using ensemble method

Handle URI:
http://hdl.handle.net/10754/622233
Title:
Path planning in uncertain flow fields using ensemble method
Authors:
Wang, Tong ( 0000-0001-8267-716X ) ; Le Maître, Olivier P.; Hoteit, Ibrahim ( 0000-0002-3751-4393 ) ; Knio, Omar
Abstract:
An ensemble-based approach is developed to conduct optimal path planning in unsteady ocean currents under uncertainty. We focus our attention on two-dimensional steady and unsteady uncertain flows, and adopt a sampling methodology that is well suited to operational forecasts, where an ensemble of deterministic predictions is used to model and quantify uncertainty. In an operational setting, much about dynamics, topography, and forcing of the ocean environment is uncertain. To address this uncertainty, the flow field is parametrized using a finite number of independent canonical random variables with known densities, and the ensemble is generated by sampling these variables. For each of the resulting realizations of the uncertain current field, we predict the path that minimizes the travel time by solving a boundary value problem (BVP), based on the Pontryagin maximum principle. A family of backward-in-time trajectories starting at the end position is used to generate suitable initial values for the BVP solver. This allows us to examine and analyze the performance of the sampling strategy and to develop insight into extensions dealing with general circulation ocean models. In particular, the ensemble method enables us to perform a statistical analysis of travel times and consequently develop a path planning approach that accounts for these statistics. The proposed methodology is tested for a number of scenarios. We first validate our algorithms by reproducing simple canonical solutions, and then demonstrate our approach in more complex flow fields, including idealized, steady and unsteady double-gyre flows.
KAUST Department:
Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division
Citation:
Wang T, Le Maître OP, Hoteit I, Knio OM (2016) Path planning in uncertain flow fields using ensemble method. Ocean Dynamics 66: 1231–1251. Available: http://dx.doi.org/10.1007/s10236-016-0979-2.
Publisher:
Springer Nature
Journal:
Ocean Dynamics
Issue Date:
20-Aug-2016
DOI:
10.1007/s10236-016-0979-2
Type:
Article
ISSN:
1616-7341; 1616-7228
Sponsors:
This work was supported in part by the Uncertainty Quantification Center at King Abdullah University of Science and Technology.
Additional Links:
http://link.springer.com/article/10.1007%2Fs10236-016-0979-2
Appears in Collections:
Articles; Computer, Electrical and Mathematical Sciences and Engineering (CEMSE) Division

Full metadata record

DC FieldValue Language
dc.contributor.authorWang, Tongen
dc.contributor.authorLe Maître, Olivier P.en
dc.contributor.authorHoteit, Ibrahimen
dc.contributor.authorKnio, Omaren
dc.date.accessioned2017-01-02T08:42:39Z-
dc.date.available2017-01-02T08:42:39Z-
dc.date.issued2016-08-20en
dc.identifier.citationWang T, Le Maître OP, Hoteit I, Knio OM (2016) Path planning in uncertain flow fields using ensemble method. Ocean Dynamics 66: 1231–1251. Available: http://dx.doi.org/10.1007/s10236-016-0979-2.en
dc.identifier.issn1616-7341en
dc.identifier.issn1616-7228en
dc.identifier.doi10.1007/s10236-016-0979-2en
dc.identifier.urihttp://hdl.handle.net/10754/622233-
dc.description.abstractAn ensemble-based approach is developed to conduct optimal path planning in unsteady ocean currents under uncertainty. We focus our attention on two-dimensional steady and unsteady uncertain flows, and adopt a sampling methodology that is well suited to operational forecasts, where an ensemble of deterministic predictions is used to model and quantify uncertainty. In an operational setting, much about dynamics, topography, and forcing of the ocean environment is uncertain. To address this uncertainty, the flow field is parametrized using a finite number of independent canonical random variables with known densities, and the ensemble is generated by sampling these variables. For each of the resulting realizations of the uncertain current field, we predict the path that minimizes the travel time by solving a boundary value problem (BVP), based on the Pontryagin maximum principle. A family of backward-in-time trajectories starting at the end position is used to generate suitable initial values for the BVP solver. This allows us to examine and analyze the performance of the sampling strategy and to develop insight into extensions dealing with general circulation ocean models. In particular, the ensemble method enables us to perform a statistical analysis of travel times and consequently develop a path planning approach that accounts for these statistics. The proposed methodology is tested for a number of scenarios. We first validate our algorithms by reproducing simple canonical solutions, and then demonstrate our approach in more complex flow fields, including idealized, steady and unsteady double-gyre flows.en
dc.description.sponsorshipThis work was supported in part by the Uncertainty Quantification Center at King Abdullah University of Science and Technology.en
dc.publisherSpringer Natureen
dc.relation.urlhttp://link.springer.com/article/10.1007%2Fs10236-016-0979-2en
dc.subjectOptimal path planningen
dc.subjectHeading controlen
dc.subjectEnsemble forecasten
dc.subjectPolynomial chaosen
dc.titlePath planning in uncertain flow fields using ensemble methoden
dc.typeArticleen
dc.contributor.departmentComputer, Electrical and Mathematical Sciences and Engineering (CEMSE) Divisionen
dc.identifier.journalOcean Dynamicsen
dc.contributor.institutionLIMSI-CNRS, BP 133, Orsay, 91403, Franceen
kaust.authorWang, Tongen
kaust.authorHoteit, Ibrahimen
kaust.authorKnio, Omaren
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