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Robotic Planning under Uncertainty in Spatiotemporal Environments in Expeditionary Science

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arXiv 2022年

作者： Preston, Victoria Flaspohler, Genevieve Michel, Anna P.M. Fisher, John W. Roy, Nicholas MIT-WHOI Joint Program Massachusetts Institute of Technology CambridgeMA02139 United States Applied Ocean Physics and Engineering Woods Hole Oceanographic Institution United States Computer Science and Artificial Intelligence Laboratory Massachusetts Institute of Technology CambridgeMA02139 United States

In the expeditionary sciences, spatiotemporally varying environments - hydrothermal plumes, algal blooms, lava flows, or animal migrations - are ubiquitous. Mobile robots are uniquely well-suited to study these dynamic, mesoscale natural environments. We formalize expeditionary science as a sequential decision-making problem, modeled using the language of partially-observable Markov decision processes (POMDPs). Solving the expeditionary science POMDP under real-world constraints requires efficient probabilistic modeling and decision-making in problems with complex dynamics and observational models. Previous work in informative path planning, adaptive sampling, and experimental design have shown compelling results, largely in static environments, using data-driven models and information-based rewards. However, these methodologies do not trivially extend to expeditionary science in spatiotemporal environments: they generally do not make use of scientific knowledge such as equations of state dynamics, they focus on information gathering as opposed to scientific task execution, and they make use of decision-making approaches that scale poorly to large, continuous problems with long planning horizons and real-time operational constraints. In this work, we discuss these and other challenges related to probabilistic modeling and decision-making in expeditionary science, and present some of our preliminary work that addresses these gaps. We ground our results in a real expeditionary science deployment of an autonomous underwater vehicle (AUV) in the deep ocean for hydrothermal vent discovery and characterization. Our concluding thoughts highlight remaining work to be done, and the challenges that merit consideration by the reinforcement learning and decision-making community. Copyright © 2022, The Authors. All rights reserved.

关键词： Decision making

Glacial isostatic adjustment shifted early Holocene river hydrology in Maine, USA

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Geology 2025年第5期53卷 446-450页

作者： Sanborn, Lily H. Pico, Tamara Donnelly, Jeffrey P. Perron, J. Taylor Massachusetts Institute of Technology Woods Hole Oceanographic Institution Joint Program in Oceanography/Applied Ocean Science and Engineering Cambridge 02139 Woods HoleMA02543 United States Earth & Planetary Sciences Department University of California Santa Cruz Santa CruzCA95064 United States Department of Geology & Geophysics Woods Hole Oceanographic Institution Woods HoleMA02543 United States Department of Earth Atmospheric & Planetary Sciences Massachusetts Institute of Technology CambridgeMA02139 United States

Glacial isostatic adjustment produces crustal deformation capable of altering the slope of the landscape and diverting surface water drainage, thereby modulating the hydraulic conditions that govern river evolution. These effects can be especially important near the margins of ice sheets. In Maine, USA, post-glacial changes in sedimentation within major river systems have been interpreted as the result of regional tilting and drainage rerouting due to glacial isostatic adjustment. In this study, we model isostatic adjustment driven by retreat of the Laurentide Ice Sheet, quantify the associated tilting and drainage rerouting, and explore how these changes impacted sediment transport in Maine’s rivers. Through an analysis of changes to river slope and drainage area produced by glacial isostatic adjustment, we show that ice sheet retreat altered the median sediment grain size that rivers could entrain. We also find support for previous estimates of the timing and direction of drainage reversal at Moosehead Lake, Maine’s largest lake. Our results suggest that the history of sedimentation in Maine’s rivers reflects time-dependent effects of glacial isostatic adjustment that are superimposed on any changes in runoff associated with deglaciation. Further, our case study demonstrates that isostatic adjustment affects alluvial channel evolution and sediment delivery to the coastline for several millennia after an ice sheet retreats. © 2025 Geological Society of America.

关键词： Glacial geology

Impact of El Niño-Southern Oscillation on the Alkalinity and Salinity of a Coral Reef Lagoon in the Equatorial Pacific—Observations and a Model

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Journal of Geophysical Research: oceans 2025年第6期130卷

作者： Steven J. Lentz Anne L. Cohen Nathaniel R. Mollica Michael Fox Weifeng (Gordon) Zhang Phadtaya Poemnamthip Daniel C. McCorkle Woods Hole Oceanographic Institution Woods Hole MA USA Biological and Environmental Sciences and Engineering Division (BESE) Red Sea Research Center Marine Science Program King Abdullah University of Science and Technology Thuwal Kingdom of Saudi Arabia MIT-WHOI Joint Program in Oceanography/Applied Ocean Science and Engineering Woods Hole MA USA

The impacts of El Niño-Southern Oscillation (ENSO) on salinity and alkalinity in an equatorial coral reef lagoon (Kanton) are investigated using water samples collected in three non-El Niño years (1973, 2012, and 2018) and one El Niño year (2015). A one-dimensional, advective-diffusive model is developed to aid in the interpretation of the sparse observations and make estimates of net ecosystem calcification (NEC) rates. The Kanton lagoon experiences extreme salinity and alkalinity variations driven by ENSO variations in precipitation. During the non-El Niño years, salinity increases from the ocean (35.5 psu) to the back of the lagoon (38 psu) because evaporation exceeds precipitation, and water resides in the back of the lagoon for ∼180 days. Early in the 2015–2016 El Niño, the back of the lagoon is only ∼1 psu saltier than the ocean because precipitation had begun to exceed evaporation. The model suggests that during El Niño events, when precipitation substantially exceeds evaporation, the back of the lagoon is less salty than the ocean (30–32 psu). Alkalinity variations in the lagoon are primarily due to dilution or concentration driven by the ENSO variations in precipitation and NEC that causes an alkalinity deficit of ∼250 μmol/kg in the back of the lagoon. The estimated NEC rate in 2015 is ∼25% lower (4.1 mmol/day) than in the non-El Niño years (5.3–5. 7 mmol/day). The NEC rates and coral cover measurements indicate that the Kanton lagoon has recovered from the complete loss of coral cover during the 2002–2003 El Niño. Rainfall variations cause the Kanton lagoon to be much saltier than the ocean between El Niño events and probably much fresher during El Niño events Large variations in alkalinity in the Kanton lagoon are due to dilution driven by precipitation and ecosystem calcification Calcification rate estimates suggest the Kanton lagoon has recovered from a complete loss of coral during the 2002–2003 El Niño This study examines the impact of large variatio

关键词： coral reef lagoon El Nino–Southern Oscillation alkalinity salinity net ecosystem calcification residence time

Active reward learning for co-robotic vision based exploration in bandwidth limited environments

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arXiv 2020年

作者： Jamieson, Stewart How, Jonathan P. Girdhar, Yogesh MIT-WHOI Joint Program in Applied Ocean Science and Engineering United States United States

We present a novel POMDP problem formulation for a robot that must autonomously decide where to go to collect new and scientifically relevant images given a limited ability to communicate with its human operator. From this formulation we derive constraints and design principles for the observation model, reward model, and communication strategy of such a robot, exploring techniques to deal with the very highdimensional observation space and scarcity of relevant training data. We introduce a novel active reward learning strategy based on making queries to help the robot minimize path "regret" online, and evaluate it for suitability in autonomous visual exploration through simulations. We demonstrate that, in some bandwidth-limited environments, this novel regret-based criterion enables the robotic explorer to collect up to 17% more reward per mission than the next-best criterion. Copyright © 2020, The Authors. All rights reserved.

关键词： Machine design

Active Reward Learning for Co-Robotic Vision Based Exploration in Bandwidth Limited Environments

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Active Reward Learning for Co-Robotic Vision Based Explorati...

IEEE International Conference on Robotics and Automation (ICRA)

作者： Stewart Jamieson Jonathan P. How Yogesh Girdhar MIT-WHOI Joint Program in Applied Ocean Science and Engineering Department of Aeronautics and Astronautics at the Massachusetts Institute of Technology (MIT) Applied Ocean Physics and Engineering Department The Woods Hole Oceanographic Institution (WHOI)

ISBN: (数字)9781728173955

ISBN: (纸本)9781728173962

We present a novel POMDP problem formulation for a robot that must autonomously decide where to go to collect new and scientifically relevant images given a limited ability to communicate with its human operator. From this formulation we derive constraints and design principles for the observation model, reward model, and communication strategy of such a robot, exploring techniques to deal with the very high-dimensional observation space and scarcity of relevant training data. We introduce a novel active reward learning strategy based on making queries to help the robot minimize path "regret" online, and evaluate it for suitability in autonomous visual exploration through simulations. We demonstrate that, in some bandwidth-limited environments, this novel regret-based criterion enables the robotic explorer to collect up to 17% more reward per mission than the next-best criterion.

关键词： Robot sensing systems Semantics Bandwidth Computational modeling Visualization Trajectory

Reprocessing the NEAT Dataset: Preliminary Results

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arXiv 2025年

作者： Nugent, C.R. Bauer, J.M. Benitez, O. Blain, M. D’Souza, N. Garimella, S. Goldwater, M. Kim, Y. Larsen, H.C.G. Linder, T. Mackowiak, K. McGinnis, Z. Pan, E. Pedersen, C.C. Sadhwani, P. Spoto, F. Tan, N.J. Vereš, P. Xue, C. Olin College of Engineering 1000 Olin Way NeedhamMA02492 United States Department of Astronomy University of Maryland College ParkMD20742 United States Department of Earth and Space Sciences College of the Canyons Santa ClaritaCA91355 United States MIT-WHOI Joint Program in Applied Ocean Science & Engineering Cambridge and Woods Hole MA United States Department of Applied Ocean Physics & Engineering Woods Hole Oceanographic Institution 266 Woods Hole Road MS #55 Woods HoleMA02543-1050 United States Aalborg University Fibigerstræde 16 Aalborg9220 Denmark Planetary Science Institute TucsonAZ85719 United States Minor Planet Center Smithsonian Astrophysical Observatory 60 Garden Street CambridgeMA02138 United States School of Physical and Chemical Sciences Te Kura Matū University of Canterbury Private Bag 4800 Christchurch8140 New Zealand

We have created a new image analysis pipeline to reprocess images taken by the Near Earth Asteroid Tracking survey and have applied it to ten nights of observations. This work is the first large-scale reprocessing of images from an asteroid discovery survey in which thousands of archived images are re-calibrated, searched for minor planets, and resulting observations are reported to the Minor Planet Center. We describe the software used to extract, calibrate, and clean sources from the images, including specific techniques that accommodate the unique features of these archival images. This pipeline is able to find fainter asteroids than the original pipeline. © 2025, CC BY.

关键词： Asteroids

Symptomatic and asymptomatic domoic acid exposure in zebrafish (Danio rerio) revealed distinct non-overlapping gene expression patterns in the brain

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Aquatic Toxicology 2022年 252卷 106310页

作者： Hidayat, Alia S. Lefebvre, Kathi A. MacDonald, James Bammler, Theo Aluru, Neelakanteswar MIT-WHOI Joint Program in Oceanography/Applied Ocean Science & Engineering Cambridge and Woods Hole MA United States Biology Department and Woods Hole Center for Oceans and Human Health Woods Hole Oceanographic Institution Woods Hole MA United States Environmental and Fisheries Science Division Northwest Fisheries Science Center National Marine Fisheries Service NOAA Seattle WA United States Department of Environmental and Occupational Health University of Washington Seattle WA United States

Domoic acid (DA) is a naturally produced neurotoxin synthesized by marine diatoms in the genus Pseudo-nitzschia. DA accumulates in filter-feeders such as shellfish, and can cause severe neurotoxicity when contaminated seafood is ingested, resulting in Amnesic Shellfish Poisoning (ASP) in humans. Overt clinical signs of neurotoxicity include seizures and disorientation. ASP is a significant public health concern, and though seafood regulations have effectively minimized the human risk of severe acute DA poisoning, the effects of exposure at asymptomatic levels are poorly understood. The objective of this study was to determine the effects of exposure to symptomatic and asymptomatic doses of DA on gene expression patterns in the zebrafish brain. We exposed adult zebrafish to either a symptomatic (1.1 ± 0.2 μg DA/g fish) or an asymptomatic (0.31 ± 0.03 µg DA/g fish) dose of DA by intracelomic injection and sampled at 24, 48 and 168 h post-injection. Transcriptional profiling was done using Agilent and Affymetrix microarrays. Our analysis revealed distinct, non-overlapping changes in gene expression between the two doses. We found that the majority of transcriptional changes were observed at 24 h post-injection with both doses. Interestingly, asymptomatic exposure produced more persistent transcriptional effects - in response to symptomatic dose exposure, we observed only one differentially expressed gene one week after exposure, compared to 26 in the asymptomatic dose at the same time (FDR <0.05). GO term analysis revealed that symptomatic DA exposure affected genes associated with peptidyl proline modification and retinoic acid metabolism. Asymptomatic exposure caused differential expression of genes that were associated with GO terms including circadian rhythms and visual system, and also the neuroactive ligand-receptor signaling KEGG pathway. Overall, these results suggest that transcriptional responses are specific to the DA dose and that asymptomatic exposure can

关键词： Domoic acid Excitotoxin Glutamate Harmful algal bloom toxin

Streaming scene maps for co-robotic exploration in bandwidth limited environments

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arXiv 2019年

作者： Girdhar, Yogesh Cai, Levi Jamieson, Stewart McGuire, Nathan Flaspohler, Genevieve Suman, Stefano Claus, Brian MIT Media Lab MIT-WHOI Joint Program in Applied Ocean Science and Engineering Mechanical Engineering Department Northeastern University

This paper proposes a bandwidth tunable technique for real-time probabilistic scene modeling and mapping to enable co-robotic exploration in communication constrained environments such as the deep sea. The parameters of the system enable the user to characterize the scene complexity represented by the map, which in turn determines the bandwidth requirements. The approach is demonstrated using an underwater robot that learns an unsupervised scene model of the environment and then uses this scene model to communicate the spatial distribution of various high-level semantic scene constructs to a human operator. Preliminary experiments in an artificially constructed tank environment as well as simulated missions over a 10m×10m coral reef using real data show the tunability of the maps to different bandwidth constraints and science interests. To our knowledge this is the first paper to quantify how the free parameters of the unsupervised scene model impact both the scientific utility of and bandwidth required to communicate the resulting scene model. Copyright © 2019, The Authors. All rights reserved.

关键词： Bandwidth

Correction: Reverse engineering environmental metatranscriptomes clarifies best practices for eukaryotic assembly

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BMC bioinformatics 2023年第1期24卷 185页

作者： Arianna I Krinos Natalie R Cohen Michael J Follows Harriet Alexander MIT-WHOI Joint Program in Oceanography and Applied Ocean Science and Engineering Cambridge and Woods Hole MA USA. akrinos@mit.edu. Department of Biology Woods Hole Oceanographic Institution Woods Hole MA USA. akrinos@mit.edu. Department of Earth Atmospheric and Planetary Science Massachusetts Institute of Technology Cambridge MA USA. akrinos@mit.edu. Skidaway Institute of Oceanography University of Georgia Savannah GA USA. Department of Earth Atmospheric and Planetary Science Massachusetts Institute of Technology Cambridge MA USA. Department of Biology Woods Hole Oceanographic Institution Woods Hole MA USA. halexander@whoi.edu.