Underwater Thruster Saturation Detection and Prevention Considering Battery Voltage Sag

ABSTRACT This paper reports on the development of a control module that detects and effectively prevents thruster saturation for an autonomous underwater vehicle (AUV). A model has been developed to approximate the maximum available thrust, per thruster, as a function of the battery voltage sag. A thruster would be considered to be in saturation if its reference input exceeds its particular output limit. This ratio can be expressed as a scalar value, which can be used to adjust the reference thrust vector that is fed to the thruster control system. This approach can minimize the total error vector in the vehicle kinematics

Editorial: Robotic In-Situ Servicing, Assembly and Manufacturing

This research topic is dedicated to articles focused on robotic manufacturing, assembly, and servicing utilizing in-situ resources, especially for space robotic applications. The purpose was to gather resource material for researchers from a variety of disciplines to identify common themes, formulate problems, and share promising technologies for autonomous large-scale construction, servicing, and assembly robots. The articles under this special topic provide a snapshot of several key technologies under development to support on-orbit robotic servicing, assembly, and manufacturing

Genetic mechanisms of critical illness in COVID-19.

Host-mediated lung inflammation is present1, and drives mortality2, in the critical illness caused by coronavirus disease 2019 (COVID-19). Host genetic variants associated with critical illness may identify mechanistic targets for therapeutic development3. Here we report the results of the GenOMICC (Genetics Of Mortality In Critical Care) genome-wide association study in 2,244 critically ill patients with COVID-19 from 208 UK intensive care units. We have identified and replicated the following new genome-wide significant associations: on chromosome 12q24.13 (rs10735079, P = 1.65 × 10-8) in a gene cluster that encodes antiviral restriction enzyme activators (OAS1, OAS2 and OAS3); on chromosome 19p13.2 (rs74956615, P = 2.3 × 10-8) near the gene that encodes tyrosine kinase 2 (TYK2); on chromosome 19p13.3 (rs2109069, P = 3.98 ×  10-12) within the gene that encodes dipeptidyl peptidase 9 (DPP9); and on chromosome 21q22.1 (rs2236757, P = 4.99 × 10-8) in the interferon receptor gene IFNAR2. We identified potential targets for repurposing of licensed medications: using Mendelian randomization, we found evidence that low expression of IFNAR2, or high expression of TYK2, are associated with life-threatening disease; and transcriptome-wide association in lung tissue revealed that high expression of the monocyte-macrophage chemotactic receptor CCR2 is associated with severe COVID-19. Our results identify robust genetic signals relating to key host antiviral defence mechanisms and mediators of inflammatory organ damage in COVID-19. Both mechanisms may be amenable to targeted treatment with existing drugs. However, large-scale randomized clinical trials will be essential before any change to clinical practice

Guidance and control for underactuated Autonomous Underwater Vehicles

The main focus of this paper is on the motion planning problem for an under-actuated, submerged, Omni-directional autonomous vehicle. Underactuation is extremely important to consider in ocean research and exploration. Battery failure, actuator malfunction and electronic shorts are a few reasons that may cause the vehicle to lose direct control of one or more degrees-of-freedom. Underactuation is also critical to understand when designing vehicles for specific tasks, such as torpedo-shaped vehicles. An under-actuated vehicle is less controllable, and hence, the motion planning problem is more difficult. Here, we present techniques based on geometric control to provide solutions to the under-actuated motion planning problem for a submerged underwater vehicle. Our results are validated with experiments

Efficient control of an Autonomous Underwater Vehicle while accounting for thruster failure

This paper is concerned with the design and implementation of control strategies onto a test-bed vehicle with six degrees-of-freedom. We design our trajectories to be efficient in time and in power consumption. Moreover, we also consider cases when actuator failure can arise and discuss alternate control strategies in this situation. Our calculations are supplemented by experimental results

SCHEMI INTEROPERABILITA' BIM-BPS: CONTROLLO DELLA IAQ IN UNA CLASSE TRAMITE DCV-CO2 BASED

Conversione dinamica del modello BIM nei modelli di analisi prestazionale (BPS), stato attuale dell'interoperabilità dei vari software disponibili per la simulazione energetica dinamica nell'ambito BIM. La modellazione BIM è riconosciuta come uno dei processi e tecnologie più importanti che può migliorare la qualità della progettazione, della costruzione e della gestione operativa del bene "edificio". Si tratta intrinsecamente di un processo di digitalizzazione che consente la simulazione ed ottimizzazione per migliorare le performance, ridurre i costi e ridurre i tempi di costruzione. BIM emerge come uno degli strumenti più importanti per una progettazione sostenibile, energeticamente. Caso studio sull'utilizzo della Ventilazione meccanica per il controllo della CO_2 (DCV-CO2 Based) in una classe scolastica, tramite simulazione dinamica energyplus/designbuilder, analisi dei risparmi ottenibili e confronto con un sistema CAV, secondo le normative sulla IAQ

Introduction to autonomous manipulation: case study with an underwater robot, SAUVIM

“Autonomous manipulation” is a challenge in robotic technologies. It refers to the capability of a mobile robot system with one or more manipulators that performs intervention tasks requiring physical contacts in unstructured environments and without continuous human supervision. Achieving autonomous manipulation capability is a quantum leap in robotic technologies as it is currently beyond the state of the art in robotics. This book addresses issues with the complexity of the problems encountered in autonomous manipulation including representation and modeling of robotic structures, kinematic and dynamic robotic control, kinematic and algorithmic singularity avoidance, dynamic task priority, workspace optimization and environment perception. Further development in autonomous manipulation should be able to provide robust improvements of the solutions for all of the above issues. The book provides an extensive tract on sensory-based autonomous manipulation for intervention tasks in unstructured environments. After presenting the theoretical foundations for kinematic and dynamic modelling as well as task-priority based kinematic control of multi-body systems, the work is focused on one of the most advanced underwater vehicle-manipulator system, SAUVIM (Semi-Autonomous Underwater Vehicle for Intervention Missions). Solutions to the problem of target identification and localization are proposed, a number of significant case studies are discussed and practical examples and experimental/simulation results are presented. The book may inspire the robot research community to further investigate critical issues in autonomous manipulation and to develop robot systems that can profoundly impact our society for the better

Algorithmic singularities avoidance in task-priority based controller for redundant manipulators

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A real-time approach for singularity avoidance in Resolved Motion Rate Control of Robotic Manipulators

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