1,721,037 research outputs found
PROGETTO E SVILUPPO DI SISTEMI DI CONTROLLO ATTIVI E PASSIVI PER LA SICUREZZA STRADALE DEL MOTOVEICOLO
Full text linkThis thesis describes the results of my PhD studies during which I worked on the development of systems for the motorcycle safety. The main result of this work is the development of a rider assistant system within the SAFERIDER European project which alerts in advance the rider about some risky situations that are about to occur while riding. This thesis exposes the SAFERIDER project and describes the main contributes given to this assistant system.
My work started on the MDRG riding simulator in order to make it to become a suitable tool for research. As a result, today this simulator is the state of the art in motorcycle simulation and has the specific capabilities to simulate digital control systems active on the vehicle and to perform hardware-in-the-loop tests on can-bus interfaced devices. Thanks to this characteristic, this simulator has been chosen as one of the few virtual demonstrators for the safety systems developed in the SAFERIDER project and it has been also involved in the 2BESAFE project as a tool to study the rider’s behavior. This thesis exposes the simulator’s architecture and the most relevant technical solutions implemented inside its software. Two digital control systems that are implemented in the simulator are then presented: an ABS and a traction control logic.
A minor research topic was the development of a Virtual Rider for numerical analysis of the vehicle dynamics. This control architecture is presented and it is developed to ride the multibody vehicle model along an assigned trajectory with an arbitrary speed profile in a time-domain simulation.Questa tesi riassume i risultati del periodo di dottorato durante il quale mi sono occupato dello studio e dello sviluppo di sistemi di assistenza alla guida orientati alla sicurezza per il motoveicolo. Il risultato principale di questo lavoro è rappresentato dallo sviluppo di un sistema di assistenza alla guida contestuale al progetto europeo SAFERIDER che implementa delle funzionalità avanzate per avvertire preventivamente il pilota nel caso si presentino delle condizioni di pericolo durante la guida. La tesi espone le generalità di questo progetto ed entra nel merito dei contributi dati allo sviluppo di questo sistema di sicurezza.
Il percorso di ricerca è iniziato dal potenziamento del simulatore di guida motociclistico del gruppo MDRG con l’obiettivo di renderlo a tutti gli effetti uno strumento adatto alla ricerca. Come risultato, questo strumento, ad oggi, rappresenta lo stato dell’arte in materia di simulatori motociclistici ed ha la peculiare caratteristica di permettere la simulazione del comportamento di diverse logiche digitali di controllo che agiscono sul veicolo e di essere uno strumento ideale per il testing hardware-in-the-loop di dispositivi hardware ad interfacciamento su bus di campo progettati per il motoveicolo. Grazie a queste caratteristiche, questo simulatore è stato selezionato come uno dei pochi dimostratori virtuali dei sistemi di sicurezza sviluppati nel progetto europeo SAFERIDER ed è stato coinvolto nel progetto europeo 2BESAFE come strumento per lo studio comportamentale dei piloti. La tesi espone l’architettura del simulatore e gli aspetti delle soluzioni tecniche più importanti implementati nel suo software. Vengono poi descritti due sistemi di controllo digitali implementati nel simulatore: un ABS e un controllo di trazione.
L’ultima parte è dedicata al tema minore relativo all’implementazione di un pilota virtuale contestualmente al settore di ricerca dell’analisi e la simulazione numerica della dinamica del veicolo. L’architettura di controllo proposta ha come obiettivo la produzione di simulazioni nel dominio del tempo in cui un modello multibody della motocicletta si muove lungo una traiettoria arbitraria con profilo di velocità assegnato
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Development and Testing of Assistant Rider Systems with the UNIPD Motorcycle Riding Simulator
No full textVariations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Advanced Rider Assistance Systems for motorcycles
No full textThis paper illustrates the Advanced Rider Assistance Systems (ARAS) developed at the University
of Padova within the European Research project SAFERIDER (www.saferider-eu.org), which aims
at studying the potential of ARAS to enhance rider safety, comfort and, hopefully, reduce fatalities.
Three different ARAS functions have been designed, implemented and validated with a common
architecture: the Curve Warning (CW), Frontal Collision Warning (FCW) and Intersection Support
(IS). These systems are able to detect in advance potential dangerous situations and warn the rider
by means of suitable Humane Machine Interface (HMI) elements.
This paper explains in detail SAFERIDER ARAS concepts, illustrates their integration first into
the riding simulator of the University of Padova and then into a real vehicle for final validation, and
finally summarize pilot tests results. ARAS systems are organized into a three layers architecture:
perception, decision and action. As shown in Figure 1, the perception layer includes sensors like
GPS, Inertial Measurement Unit and Laser scanner. Sensors are connected to a dedicated CAN bus
that gathers scenario information to the decision layer. The latter consists of the ARAS Control
Module, which actually is a PC/104+, and manages ARAS software, i.e. a Scenario Reconstruction
module. This module produces a consistent estimate of the vehicles state of motion and position,
which are the input of FCW, CW and IS modules. These modules evaluate the risk of the riding
according to the scenario and drive the action layer, which includes the HMI manager and a set of
HMI elements (visual display, haptic handle, vibratinggloveand helmet) employedto warn the rider
on acoustic, visual and tactile channels
Advanced Motorcycle Virtual Rider
No full textThe target of this work is the development of a motorcycle virtual rider model that plans a trajectory and follows it. The reference speed and trajectory are obtained by applying the optimal manoeuvre method (i.e. a nonlinear optimal control technique) to a basic model of the motorcycle. Then, the vehicle control and guidance are obtained using a PID architecture and the gains vary with speed. Separated loops for speed and lateral motion controls have been implemented, the lateral motion control is complex because of the motorcycle instability, whereas the longitudinal control is simpler. The characteristics of the PID control are illustrated and discussed in detail, some examples are given for a cornering manoeuvre first and then for a run in the Mugello circuit
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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