Zig-zag wanderer: Towards adaptive tracking of time-varying coherent structures in the ocean

Similar to the atmosphere, coherent structures, e.g., fronts, exist in the ocean. These frontal structures are known to be highly productive, supporting the whole spectrum of marine life. Ocean fronts are dynamic in time and space, and are a key component to a comprehensive knowledge of ocean dynamics and aquatic ecosystems in relation to climate change. However, dynamic features such as fronts are difficult to study through conventional oceanographic techniques. In this paper, we build upon our previous work in sampling and tracking an ocean front based on predictions and/or priors. Specifically, given a prior (that may not be accurate or up-to-date) we present and experimentally validate a method for an autonomous surface or underwater vehicle to plan a mission and adapt this mission on-the-go to track a dynamic, but coherent, structure. Experimental results using a novel indoor testbed, capable of creating controllable fluidic features in an indoor laboratory setting, are presented. These results demonstrate that the vehicle is able to adapt its path to follow a desired, time-varying contour.