{"id":3747,"date":"2016-02-03T12:00:48","date_gmt":"2016-02-03T17:00:48","guid":{"rendered":"http:\/\/mseas.mit.edu\/?p=3747"},"modified":"2021-07-06T13:07:07","modified_gmt":"2021-07-06T17:07:07","slug":"energy-based-path-planning-by-stochastic-dynamically-orthogonal-level-set-optimization","status":"publish","type":"post","link":"https:\/\/mseas.mit.edu\/?p=3747","title":{"rendered":"Energy-optimal Path Planning by Stochastic Dynamically Orthogonal Level-Set Optimization"},"content":{"rendered":"A stochastic optimization methodology is formulated for computing energy&#8211;optimal paths from among time&#8211;optimal paths of autonomous vehicles navigating in a dynamic flow field. Based on partial differential equations, the methodology rigorously leverages the level&#8211;set equation that governs time&#8211;optimal reachability fronts for a given relative vehicle speed function. To set up the energy optimization, the relative vehicle speed is considered to be stochastic and new stochastic Dynamically Orthogonal (DO) level&#8211;set equations are derived. Their solution provides the distribution of time&#8211;optimal reachability fronts and corresponding distribution of time&#8211;optimal paths. An optimization is then performed on the vehicle&#8217;s energy&#8211;time joint distribution to select the energy&#8211;optimal paths for each arrival time, among all stochastic time&#8211;optimal paths for that arrival time. Numerical schemes to solve the reduced stochastic DO level&#8211;set equations are obtained and accuracy and efficiency considerations are discussed. These reduced equations are first shown to be efficient at solving the governing stochastic level-sets, in part by comparisons with direct Monte Carlo simulations.To validate the methodology and illustrate its overall accuracy, comparisons with `semi&#8211;analytical&#8217; energy&#8211;optimal path solutions are then completed. In particular, we consider the energy&#8211;optimal crossing of a canonical steady front and set up its `semi&#8211;analytical&#8217; solution using a dual energy&#8211;time nested nonlinear optimization scheme. We then showcase the inner workings and nuances of the energy&#8211;optimal path planning, considering different mission scenarios. Finally, we study and discuss results of energy-optimal missions in a strong dynamic double&#8211;gyre flow field. ","protected":false},"excerpt":{"rendered":"<p>A stochastic optimization methodology is formulated for computing energy&#8211;optimal paths from among time&#8211;optimal paths of autonomous vehicles navigating in a dynamic flow field. Based on partial differential equations, the methodology rigorously leverages the level&#8211;set equation that governs time&#8211;optimal reachability fronts for a given relative vehicle speed function. To set up the energy optimization, the relative [&hellip;]<\/p>\n","protected":false},"author":2,"featured_media":0,"comment_status":"open","ping_status":"closed","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[183,35,5,63],"tags":[],"class_list":["post-3747","post","type-post","status-publish","format-standard","hentry","category-science-of-autonomy","category-optimal-path-planning","category-publications","category-papers-in-refereed-journals-optimal-path-planning"],"_links":{"self":[{"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=\/wp\/v2\/posts\/3747","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=3747"}],"version-history":[{"count":4,"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=\/wp\/v2\/posts\/3747\/revisions"}],"predecessor-version":[{"id":3889,"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=\/wp\/v2\/posts\/3747\/revisions\/3889"}],"wp:attachment":[{"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=3747"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=3747"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/mseas.mit.edu\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=3747"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}