Applicazione della Realtà Virtuale nell'Analisi della Sicurezza dei Sistemi di Trasporto

Gli incidenti stradali sono una delle principali cause di morte per tutte le fasce d'età; questo vale, con percentuali diverse, per tutti gli utenti della strada. Essendo un problema globale, richiede urgente attenzione. In questa tesi il comportamento degli utenti della strada e le loro interazioni sono stati studiati con l'aiuto della realtà virtuale. È stata studiata l'interazione tra utenti della strada, infrastrutture e veicoli. Nel complesso, questa ricerca ha cercato di rispondere a diverse domande, come ad esempio: È possibile migliorare la sicurezza stradale con la realtà virtuale? È possibile migliorare il comportamento degli utenti della strada con la realtà virtuale? Questa tesi è il connubio tra realtà virtuale (sia non immersiva che immersiva), trasporti e sicurezza, e tecnologia (simulatori, visori). La scelta della realtà virtuale è stata dettata dai numerosi vantaggi che essa presenta, ovviando a tutte le insidie che si avrebbero con prove sul campo. Una ricerca sugli automobilisti con realtà virtuale di tipo non immersiva è stata condotta presso il Laboratorio Trasporti del Dipartimento di Ingegneria Civile, Edile e Ambientale dell'Università di Padova. Inoltre, uno studio riguardante i motociclisti è stato invece condotto presso il Laboratorio HRT del Dipartimento di Psicologia Generale, della stessa Università. Infine, uno studio con realtà virtuale immersiva è stato proposto per l'utente vulnerabile per eccellenza: il pedone. I circa 300 soggetti coinvolti erano utenti della strada, tra cui automobilisti (Capitolo 2), motociclisti (Capitolo 3) e pedoni (Capitolo 4). Grazie al training virtuale, con i tre diversi dispositivi, è stato possibile ottenere miglioramenti nel comportamento e quindi scoprire i reali benefici della realtà virtuale nel mondo della sicurezza dei trasporti. In primo luogo, dagli studi del Capitolo 2, è stato possibile sottolineare quanto sia fondamentale avere una corretta comprensione di un Advanced driver assistance systems (ADAS) per il suo corretto funzionamento. Attraverso l'implementazione di diversi ADAS per il controllo laterale del veicolo e la somministrazione con la tecnica del precision teaching, sono stati determinati i benefici che questi sistemi producono. Poiché il controllo laterale è una variabile di particolare interesse in termini di sicurezza, a causa delle sue numerose implicazioni ed effetti, i risultati ottenuti da queste tecnologie sono incoraggianti per la mitigazione del rischio stradale e, di conseguenza, degli incidenti. I risultati proposti, sottolineando i benefici di queste tecnologie nel tempo, confermano che si tratta di un approccio legittimo sia in termini di progettazione ADAS che nell'uso di tecniche di apprendimento. In secondo luogo, considerando gli studi dei capitoli 2 e 3, si potrebbe sostenere che sia per i conducenti di auto che di moto con stile di guida aggressivo, la presentazione di feedback per ridurre eventi bruschi e le violazioni dei limiti di velocità, produce una riduzione significativa di queste variabili. I risultati ottenuti sono stati nuovamente rilevanti in termini di sicurezza stradale: grazie alle metodologie testate in questo lavoro è possibile progettare programmi per correggere il comportamento degli utenti della strada più aggressivi e, di conseguenza, più pericolosi. Per quanto riguarda i motociclisti, è stato anche dimostrato che i benefici di questi sistemi persistono nel tempo. Infine, per quanto riguarda lo studio dei pedoni al Capitolo 4, questa tesi rappresenta uno dei primi lavori in Italia di educazione alla sicurezza stradale dei bambini con la realtà virtuale. La presente indagine, infatti, essendo parte di un progetto più ampio dedicato agli utenti vulnerabili, ha indagato il comportamento dei bambini nell'ambiente stradale. In questo senso, questo studio si è rivelato innovativo sia nei suoi obiettivi educativi, sia nei mezzi impiegati per raggiungerli.Road traffic crashes are a leading cause of death across all age groups; this applies, with different percentages, to all road users. Being a global burden, this issue demands urgent attention. In this thesis road users’ behavior and their interactions are studied with the aid of virtual reality. Road users were accordingly inserted in virtual road environments, with virtual simulators. The interaction between road users, infrastructures, and vehicles was investigated. Overall, this research attempts to answer several questions, as such: Is it possible to improve road safety with virtual reality? Is it possible to improve road user behavior with virtual reality? This thesis has carefully interwoven virtual reality (both non-immersive and immersive), transport and safety, with technology (simulators, visors). The choice of virtual reality was dictated by the many advantages it presents, obviating all the pitfalls related to risk during field tests. A research regarding non-immersive virtual reality for car drivers was conducted at the Transportation Laboratory at the Department of Civil, Environmental and Architectural Engineering at University of Padua. Moreover, a study concerning motorcyclists was instead conducted at the HRT Laboratory of the Department of General Psychology. Eventually, a study with immersive virtual reality was proposed for the vulnerable user par excellence, the pedestrian. The approximately 300 subjects involved were road users, including car drivers (Chapter 2), motorcyclists (Chapter 3) and pedestrians (Chapter 4). Thanks to the virtual training, with three different devices, it was possible to obtain improvements in behavior and therefore to uncover real benefits of virtual reality in the world of transport safety. Firstly, from the studies of Chapter 2, it was possible to stress how crucial it is to have a proper understanding of an ADAS for its correct functioning. In other words, it was illustrated to what extent an adequate understanding of ADAS is pivotal to benefit from all its advantages. Through the implementation of several ADAS for the lateral control of the vehicle and the administration with precision teaching technique, it was overall investigated how many considerable benefits they produce. Since lateral control is a variable of particular interest in terms of safety, because of its many implications and effects, the results obtained from these technologies are encouraging for the mitigation of road risk and, consequently, of accidents. The results proposed, by underlining the benefits of these technologies over time, confirm that this is a legitimate approach both in terms of ADAS design and in the use of learning techniques. Secondly, considering the studies in Chapters 2 and 3, it might be argued that for both car and motorcycle drivers with aggressive driving style, the presentation of feedback to reduce elevated gravitational-force event (EGFE) and speed limit violations, produces a significant reduction of these variables. The results obtained were again relevant in terms of road safety: thanks to the methodologies tested in this work it is possible to design programs to correct the behavior of the most aggressive, and by implication most dangerous, road users. With respect to motorcyclists, it was also demonstrated that the benefits of these systems persist over time. Finally, as far as the study of pedestrians is concerned, this thesis represents one of the first works in Italy of road safety education of children with virtual reality. The present inquiry, indeed, being part of a broader project dedicated to vulnerable users, investigated children's behavior in the street environment. In this sense, this study proved to be innovative both in its educational objectives, and in the means employed to achieve them

Analisi di effluenti tossici prodotti da incendio di stoccaggi di rifiuti

Analisi di effluenti tossici prodotti da incendio di stoccaggi di rifiuti: Simulazioni mediante il software ALOFT Applicazione del codice di prevenzione incendi a casi reali

Highway Deceleration Lane Safety: Effects of Real-Time Coaching Programs on Driving Behavior

Real-time coaching programs are designed to give feedback on driving behavior to usage-based motor insurance users; they are often general purpose programs that aim to promote smooth driving. Here, we investigated the effect of different on-board real-time coaching programs on the driving behavior on highway deceleration lanes with a driving simulator experiment. The experiment was organized into two trials. The first was a baseline trial, in which participants drove without receiving any feedback; a cluster analysis was then performed to divide participants into two groups, based on their observed driving style. One month later, a second trial was carried out, with participants driving on the same path as the first trial, this time receiving contingent feedback related to their braking/acceleration behavior. Four feedback systems were tested; overall, there were eight experimental groups, depending on the clustered driving style (aggressive and defensive), feedback modality (visual and auditory), and feedback valence (positive and negative). Speed, deceleration, trajectory, and lateral control variables, collected before and onto the deceleration lane, were investigated with mixed ANOVAs, which showed that the real-time coaching programs significantly reduced speeds and maximum deceleration values, while improving lateral control. A change toward a safer exit strategy (i.e., entering the lane before starting to decelerate) was also observed in defensive drivers

How precision teaching can shape drivers' lateral control over time

The present work describes a driving simulator experiment aimed at verifying if different feedback systems may have a positive effect on the participants’ driving behaviour in terms of lateral vehicle control over time. Participants performed the same track 4 times: the first time (baseline) no feedback was delivered, whereas the next three times either an auditory or multimodal (that is, visual and auditory) feedback was presented in case of error. About 25% of the participants in the initial sample were tested again after a month without any feedback. The results showed that the positive effect of the feedback with respect to the baseline track in terms of lower standard deviation of lateral position (SDLP), lower mean lateral speed (LS) and lower standard deviation of steering angle (SDSTEER) was maintained over time. Thanks to the precision teaching technique, drivers improved the investigated driving parameters while maintaining a correct position inside the lane

A comparative simulator study of reaction times to yellow traffic light under manual and automated driving

This study analyzes and compares reaction times of motorists at the onset of a yellow traffic light under manual and automated driving, based on two experiments performed using a driving simulator. Results show that reaction times of subjects driving an automated vehicle that experiences a failure and crosses on red when approaching a signalized intersection are higher than those of subjects driving manually. When the analysis is restricted to automated driving, results indicate significant differences between reaction times at the first system failure and those at subsequent ones

A Driving Simulator Study Exploring the Effect of Different Mental Models on ADAS System Effectiveness

This work investigated the effect of mental models on the effectiveness of an advanced driver assistance system (ADAS). The system tested was a lateral control ADAS, which informed the drivers whether the vehicle was correctly positioned inside the lane or not, with the use of two visual and one auditory stimuli. Three driving simulator experiments were performed, involving three separate groups of subjects, who received different initial exposures to the technology. In Experiment 0 subjects were not exposed to ADAS in order to be able to indicate that no effect of learning affected the results. In Experiment A subjects were not instructed on the ADAS functionalities and they had to learn on their own; in Experiment B they were directly instructed on the functionalities by reading an information booklet. In all experiments drivers performed multiple driving sessions. The mean absolute lateral position (LP) and standard deviation of lateral position (SDLP) for each driver were considered as main dependent variables to measure the effectiveness of the ADAS. Findings from this work showed that the initial mental model had an impact on ADAS effectiveness, since it produced significantly different results in terms of ADAS effectiveness, with those reading the information booklet being able to improve more and faster their lateral control

Reducing Elevated Gravitational-Force Events through visual feedback: a simulator study

Road traffic accidents represent one of the leading causes of death across all age groups globally. Most of these accidents can be directly attributed to drivers\u2019 failure to select the correct driving speed. Thus, actions aimed to mitigate inappropriate driving performance, including speeding, are needed. Here, we used a dynamic driving simulator to investigate the effects of different real-time coaching programs on driving performance, specifically on the occurrence of Elevated Gravitational-Force Events (EGFEs). Forty-three drivers underwent a two-day evaluation. On the first day, participants \u2013after an initial screening and depending on their driving style\u2013 were divided into two groups: defensive vs. aggressive drivers. On the second day, they received a different type of real time visual feedback based on their driving performance. For each of the two driving style groups, half of the drivers received contingent positive feedback (when smooth driving events occurred), the other half received contingent negative feedback (when harsh driving events occurred). Thus, there were four groups based on driving style and feedback. Overall, results showed that among aggressive drivers contingent feedback \u2013independently from its type\u2013 reduces the occurrence of EGFEs. Potential applications of the proposed methodology include its use for Pay-how-you-drive programs aimed to improve driver speed control