Search results for "Mod"
showing 10 items of 39605 documents
Assessing Urban System Vulnerabilities to Flooding to Improve Resilience and Adaptation in Spatial Planning
2018
Fluvial, pluvial and coastal flooding are the most frequent and costly natural hazard. Cities are social hubs and life in cities is reliant on a number of services and functions such as housing, healthcare, education and other key daily facilities. Urban flooding can cause significant disruption to these services and wider impacts on the population. These impacts may be short or long with a variably spatial scale: urban systems are spatially distributed and the nature of this can have significant effects on flood impacts. From an urban-planning perspective, measuring this disruption and its consequences is fundamental in order to develop more resilient cities. Whereas the assessment of phys…
The role of urban growth, climate change, and their interplay in altering runoff extremes
2018
Changes in climate and urban growth are the most influential factors affecting hydrological characteristics in urban and extra-urban contexts. The assessment of the impacts of these changes on the extreme rainfall–runoff events may have important implications on urban and extra-urban management policies against severe events, such as floods, and on the design of hydraulic infrastructures. Understanding the effects of the interaction between climate change and urban growth on the generation of runoff extremes is the main aim of this paper. We carried out a synthetic experiment on a river catchment of 64 km2to generate hourly runoff time series under different hypothetical scenarios. We impos…
Feasibility Analysis For Constrained Model Predictive Control Based Motion Cueing Algorithm
2019
International audience; This paper deals with motion control for an 8-degree-of-freedom (DOF) high performance driving simulator. We formulate a constrained optimal control that defines the dynamical behavior of the system. Furthermore, the paper brings together various methodologies for addressing feasibility issues arising in implicit model predictive control-based motion cueing algorithms.The implementation of different techniques is described and discussed subsequently. Several simulations are carried out in the simulator platform. It is observed that the only technique that can provide ensured closed-loop stability by assuring feasibility over all prediction horizons is a braking law t…
Improving the Training Methods for Designers of Flexible Production Cells in Factories of the Future
2020
This work proposes a design method for flexible manufacturing systems (FMS). The method reduces the learning curve by helping employees to solve problems related to the design and optimization of the layout, operation and control of FMS, avoiding the drawbacks of current tools. The approach uses Domain Specific Modeling Languages (DSML) for specification of FMS. The paper presents the definition of the DSML and the implementation of the graphical modeling and simulation tool bringing important contributions to development of the domain through the use of constructions from categories theory for DSML specifications. This mathematical basis allows the definition of constraints to avoid supple…
Dynamic Design Intents Capture with Formal Ontology and Perdurants Object Concept for Collaborative Product Design
2016
Loss of design intents and related information throughout the lifecycle of products are common. Capturing design intents of an assembly, which include a temporal (dynamic) stages, is even harder. This research work aims to enhance the spatiotemporal mereotopology (STM) based ontology in tune with the contemporary efforts in this research domain. The main idea with such STM ontology is to capture dynamic design intents and develop an integrated data translation framework from Computer Aided Design (CAD) system to a visualization system. This integration framework is intended to enhance design sharing in a collaborative environment. In this paper, the framework is demonstrated with a simple m…
Large multiple neighborhood search for the soft-clustered vehicle-routing problem
2021
Abstract The soft-clustered vehicle-routing problem (SoftCluVRP) is a variant of the classical capacitated vehicle-routing problem. Customers are partitioned into clusters and all customers of the same cluster must be served by the same vehicle. In this paper, we present a large multiple neighborhood search for the SoftCluVRP. We design and analyze multiple cluster destroy and repair operators as well as two post-optimization components, which are both based on variable neighborhood descent. The first allows inter-route exchanges of complete clusters, while the second searches for intra-route improvements by combining classical neighborhoods (2-opt, Or-opt, double-bridge) and the Balas-Simo…
Decoupled nonlinear adaptive control of position and stiffness for pneumatic soft robots
2020
This article addresses the problem of simultaneous and robust closed-loop control of joint stiffness and position, for a class of antagonistically actuated pneumatic soft robots with rigid links and compliant joints. By introducing a first-order dynamic equation for the stiffness variable and using the additional control degree of freedom, embedded in the null space of the pneumatic actuator matrix, an innovative control approach is introduced comprising an adaptive compensator and a dynamic decoupler. The proposed solution builds upon existing adaptive control theory and provides a technique for closing the loop on joint stiffness in pneumatic variable stiffness actuators. Under a very mi…
Comparison of Model-Based Simultaneous Position and Stiffness Control Techniques for Pneumatic Soft Robots
2020
Soft robots have been extensively studied for their ability to provide both good performance and safe human-robot interaction. In this paper, we present and compare the performance of two model-based control techniques with the common aim to independently and simultaneously control position and stiffness of a pneumatic soft robot’s joint. The dynamic system of a robot arm with flexible joints actuated by a pneumatic antagonistic pair of actuators, so-called McKibben artificial muscles, will be regarded, while its dynamic parameters will be considered imprecise. Simulation results are provided to verify the performance of the algorithms.
UJI RobInLab's approach to the Amazon Robotics Challenge 2017
2017
This paper describes the approach taken by the team from the Robotic Intelligence Laboratory at Jaume I University to the Amazon Robotics Challenge 2017. The goal of the challenge is to automate pick and place operations in unstructured environments, specifically the shelves in an Amazon warehouse. RobInLab's approach is based on a Baxter Research robot and a customized storage system. The system's modular architecture, based on ROS, allows communication between two computers, two Arduinos and the Baxter. It integrates 9 hardware components along with 10 different algorithms to accomplish the pick and stow tasks. We describe the main components and pipelines of the system, along with some e…
Analysis of hybrid vehicle transmissions with any number of modes and planetary gearing: kinematics, power flows, mechanical power losses
2021
Abstract This paper is focused on upgrading a unified parametric model, available in the literature, that can perform both the analysis and the design of Power-Split Continuously Variable Transmissions (PS-CVTs), which are particularly promising to deploy in the hybrid electric powertrain. In particular, this work is focused on the analysis of PS-CVTs and proposes a new matrix approach for identifying the basic functional parameters underlying the model from the constructive layout of the transmission. This new method does not rely on a case-specific formulation, thus befits any power-split transmission, regardless of the number of planetary and ordinary gear sets and their constructive arr…