Search results for "automatic"
showing 10 items of 730 documents
On the Stability of the Soft Pendulum With Affine Curvature: Open-Loop, Collocated Closed-Loop, and Switching Control
2022
This letter investigates the stability properties of the soft inverted pendulum with affine curvature - a template model for nonlinear control of underactuated soft robots. We look at how changes in physical parameters affect stability and equilibrium. We give conditions under which zero dynamics corresponding to a collocated choice of the output is (locally or globally) stable or unstable. We leverage these results to design a switching controller that stabilizes a class of nonlinear equilibria of the pendulum, which can drive the system from one equilibrium to another.
Casting Robotic end-effectors to reach far objects in space and planetary missions
2006
In this paper we present work aimed at developing a compact robotic device able to reach objects at far distance.The work is based on the idea of casting manipulation, and that allows to deploy an end-effector at large distances from the robot’s base by throwing (casting) it and controlling its ballistic flightusing forces transmitted through a light tether connected to the end-effector itself.
Automatic surrogate modelling technique selection based on features of optimization problems
2019
A typical scenario when solving industrial single or multiobjective optimization problems is that no explicit formulation of the problem is available. Instead, a dataset containing vectors of decision variables together with their objective function value(s) is given and a surrogate model (or metamodel) is build from the data and used for optimization and decision-making. This data-driven optimization process strongly depends on the ability of the surrogate model to predict the objective value of decision variables not present in the original dataset. Therefore, the choice of surrogate modelling technique is crucial. While many surrogate modelling techniques have been discussed in the liter…
Il Laboratorio per lo Sviluppo Sostenibile e il Risparmio Energetico (SDESLab) nell’ambito industriale siciliano
2009
L’articolo presenta le attività del Laboratorio per lo Sviluppo Sostenibile ed il Risparmio Energetico (SDESLAB) dell’Università degli Studi di Palermo nei confronti dell’ambito industriale, con particolare riguardo a quello siciliano. Vengono illustrati gli ambiti di intervento del Laboratorio: ricerca scientifica di base, consulenza alle industrie e alle imprese, formazione, informazione e divulgazione nei vari campi dello sviluppo sostenibile con particolare riguardo a energie rinnov- abili, azionamenti elettrici, automazione industriale e gestione automatizzata dell’energia. Vengono descritte le attrezzature di cui il Laboratorio si avvale per le proprie attività, i progetti di ricerca i…
Feedback Linearization Based Nonlinear Control of SynRM Drives Accounting for Self- and Cross-Saturation
2022
This article proposes a nonlinear controller based on feedback linearization (FL) for synchronous reluctance motor (SynRM) drives which takes into consideration the magnetic saturation. The proposed nonlinear FL control based control technique has been developed starting from the theoretical definition of an original dynamic model of the SynRM taking into consideration both the self- and the cross-saturation effects. Such a control technique permits the dynamics of both the speed and axis flux loops to be maintained constant independently from the load and the saturation of the iron core in both constant flux and variable direct axis flux operating conditions. Finally, sensitivity of the pe…
On shape differentiation of discretized electric field integral equation
2013
Abstract This work presents shape derivatives of the system matrix representing electric field integral equation discretized with Raviart–Thomas basis functions. The arising integrals are easy to compute with similar methods as the entries of the original system matrix. The results are compared to derivatives computed with automatic differentiation technique and finite differences, and are found to be in an excellent agreement. Furthermore, the derived formulas are employed to analyze shape sensitivity of the input impedance of a planar inverted F-antenna, and the results are compared to those obtained using a finite difference approximation.
Semi-automatic literature mapping of participatory design studies 2006--2016
2018
The paper presents a process of semi-automatic literature mapping of a comprehensive set of participatory design studies between 2006--2016. The data of 2939 abstracts were collected from 14 academic search engines and databases. With the presented method, we were able to identify six education-related clusters of PD articles. Furthermore, we point out that the identified clusters cover the majority of education-related words in the whole data. This is the first attempt to systematically map the participatory design literature. We argue that by continuing our work, we can help to perceive a coherent structure in the body of PD research.
Feature Extractors for Describing Vehicle Routing Problem Instances
2016
The vehicle routing problem comes in varied forms. In addition to usual variants with diverse constraints and specialized objectives, the problem instances themselves – even from a single shared source - can be distinctly different. Heuristic, metaheuristic, and hybrid algorithms that are typically used to solve these problems are sensitive to this variation and can exhibit erratic performance when applied on new, previously unseen instances. To mitigate this, and to improve their applicability, algorithm developers often choose to expose parameters that allow customization of the algorithm behavior. Unfortunately, finding a good set of values for these parameters can be a tedious task that…
Navigation Performance Evaluation for AutomaticGuided Vehicles
2015
International audience; —Automatic guided vehicles (AGVs), an industrial form of a mobile robot,typically navigate using a central computer commanding AGV movement on predefined paths. How well they follow these paths is not well-defined in research articles and their performance is reported in non-standard manufacturer specifications. Furthermore, AGV technology is advancing towards vision guidance to map and localize their position from onboard the vehicle, whereas performance evaluation of advanced navigation techniques is just beginning. This paper describes AGV experiments using ground truth measurement comparisonfor performance evaluationof AGV navigation. A generic test procedure and…
Thermal anomalies detection in a photovoltaic plant using artificial intelligence: Italy case studies
2021
This paper proposes the application of artificial intelligence techniques for the identification of thermal anomalies that occur in a photovoltaic system due to malfunctions or faults, with the aim to limit the energy production losses by detecting faults at an early stage. The proposed approach is based on a Thermographic Non-Destructive Test conducted with Unmanned Aerial Vehicles equipped with a thermal imaging camera, which allows the detection of abnormal operating conditions without interrupting the normal operation of the PV system rapidly and cost-effectively. The thermographic images and videos are automatically inspected using a Convolutional Neural Network, developed by an open-s…