16 research outputs found
Energy-Aware Ergodic Search: Continuous Exploration for Multi-Agent Systems with Battery Constraints
Continuous exploration without interruption is important in scenarios such as
search and rescue and precision agriculture, where consistent presence is
needed to detect events over large areas. Ergodic search already derives
continuous trajectories in these scenarios so that a robot spends more time in
areas with high information density. However, existing literature on ergodic
search does not consider the robot's energy constraints, limiting how long a
robot can explore. In fact, if the robots are battery-powered, it is physically
not possible to continuously explore on a single battery charge. Our paper
tackles this challenge, integrating ergodic search methods with energy-aware
coverage. We trade off battery usage and coverage quality, maintaining
uninterrupted exploration by at least one agent. Our approach derives an
abstract battery model for future state-of-charge estimation and extends
canonical ergodic search to ergodic search under battery constraints. Empirical
data from simulations and real-world experiments demonstrate the effectiveness
of our energy-aware ergodic search, which ensures continuous exploration and
guarantees spatial coverage.Comment: 7 pages, 7 figures, ICRA'2
Energy-Aware Planning-Scheduling for Autonomous Aerial Robots
In this paper, we present an online planning-scheduling approach for
battery-powered autonomous aerial robots. The approach consists of
simultaneously planning a coverage path and scheduling onboard computational
tasks. We further derive a novel variable coverage motion robust to airborne
constraints and an empirically motivated energy model. The model includes the
energy contribution of the schedule based on an automatic computational energy
modeling tool. Our experiments show how an initial flight plan is adjusted
online as a function of the available battery, accounting for uncertainty. Our
approach remedies possible in-flight failure in case of unexpected battery
drops, e.g., due to adverse atmospheric conditions, and increases the overall
fault tolerance.Comment: 8 pages, 6 figures, IROS'2
New opportunities and untapped scientific potential in the abyssal ocean
© The Author(s), 2022. This article is distributed under the terms of the Creative Commons Attribution License. The definitive version was published in Marlow, J., Anderson, R., Reysenbach, A.-L., Seewald, J., Shank, T., Teske, A., Wanless, V., & Soule, S. New opportunities and untapped scientific potential in the abyssal ocean. Frontiers in Marine Science, 8, (2022): 798943, https://doi.org/10.3389./fmars.2021.798943The abyssal ocean covers more than half of the Earthâs surface, yet remains understudied and underappreciated. In this Perspectives article, we mark the occasion of the Deep Submergence Vehicle Alvinâs increased depth range (from 4500 to 6500 m) to highlight the scientific potential of the abyssal seafloor. From a geologic perspective, ultra-slow spreading mid-ocean ridges, Petit Spot volcanism, transform faults, and subduction zones put the full life cycle of oceanic crust on display in the abyss, revealing constructive and destructive forces over wide ranges in time and space. Geochemically, the abyssal pressure regime influences the solubility of constituents such as silica and carbonate, and extremely high-temperature fluid-rock reactions in the shallow subsurface lead to distinctive and potentially unique geochemical profiles. Microbial residents range from low-abundance, low-energy communities on the abyssal plains to fast growing thermophiles at hydrothermal vents. Given its spatial extent and position as an intermediate zone between coastal and deep hadal settings, the abyss represents a lynchpin in global-scale processes such as nutrient and energy flux, population structure, and biogeographic diversity. Taken together, the abyssal ocean contributes critical ecosystem services while facing acute and diffuse anthropogenic threats from deep-sea mining, pollution, and climate change.We would like to thank the National Science Foundation for their support through grants NSF 2009117 and 2129431 to SAS
The TeamPlay project : analysing and optimising time, energy, and security for cyber-physical systems
Funding: This work was supported by the EU Horizon-2020 project TeamPlay (https://www.teamplay-h2020.eu), grant #779882.Non-functional properties, such as energy, time, and security (ETS) are becoming increasingly important for the programming of Cyber-Physical Systems (CPS). This paper describes TeamPlay, a research project funded under the EU Horizon 2020 programme between January 2018 and June 2021.TeamPlay aimed to provide the system designer with a toolchain for developing embedded applications where ETS properties are first-class citizens, allowing the developer to reflect directly on energy, time and security properties at the source code level. In this paper we give an overview of the TeamPlay methodology, introduce the challenges and solutions of our approach and summarise the results achieved. Overall, applying our TeamPlay methodology led to an improvement of up to 18% performance and 52% energy usage over traditional approaches.Postprin
Full-thickness resection device (FTRD) for treatment of upper gastrointestinal tract lesions: the first international experience.
Background and study aims The Full-Thickness Resection Device (FTRD) provides a novel treatment option for lesions not amenable to conventional endoscopic resection techniques. There are limited data on the efficacy and safety of FTRD for resection of upper gastrointestinal tract (GIT) lesions. Patients and methods This was an international multicenter retrospective study, including patients who had an endoscopic resection of an upper GIT lesion using the FTRD between January 2017 and February 2019. Results Fifty-six patients from 13 centers were included. The most common lesions were mesenchymal neoplasms (n = 23, 41 %), adenomas (n = 7, 13 %), and hamartomas (n = 6, 11 %). Eighty-four percent of lesions were located in the stomach, and 14 % in the duodenum. The average size of lesions was 14 mm (range 3 to 33 mm). Deployment of the FTRD was technically successful in 93 % of patients (n = 52) leading to complete and partial resection in 43 (77 %) and 9 (16 %) patients, respectively. Overall, the FTRD led to negative histological margins (R0 resection) in 38 (68 %) of patients. A total of 12 (21 %) mild or moderate adverse events (AEs) were reported. Follow-up endoscopy was performed in 31 patients (55 %), on average 88 days after the procedure (IQR 68-138 days). Of these, 30 patients (97 %) did not have any residual or recurrent lesion on endoscopic examination and biopsy, with residual adenoma in one patient (3 %). Conclusions Our results suggest a high technical success rate and an acceptable histologically complete resection rate, with a low risk of AEs and early recurrence for FTRD resection of upper GIT lesions
New Opportunities and Untapped Scientific Potential in the Abyssal Ocean
The abyssal ocean covers more than half of the Earthâs surface, yet remains understudied and underappreciated. In this Perspectives article, we mark the occasion of the Deep Submergence Vehicle Alvinâs increased depth range (from 4500 to 6500 m) to highlight the scientific potential of the abyssal seafloor. From a geologic perspective, ultra-slow spreading mid-ocean ridges, Petit Spot volcanism, transform faults, and subduction zones put the full life cycle of oceanic crust on display in the abyss, revealing constructive and destructive forces over wide ranges in time and space. Geochemically, the abyssal pressure regime influences the solubility of constituents such as silica and carbonate, and extremely high-temperature fluid-rock reactions in the shallow subsurface lead to distinctive and potentially unique geochemical profiles. Microbial residents range from low-abundance, low-energy communities on the abyssal plains to fast growing thermophiles at hydrothermal vents. Given its spatial extent and position as an intermediate zone between coastal and deep hadal settings, the abyss represents a lynchpin in global-scale processes such as nutrient and energy flux, population structure, and biogeographic diversity. Taken together, the abyssal ocean contributes critical ecosystem services while facing acute and diffuse anthropogenic threats from deep-sea mining, pollution, and climate change