115 research outputs found
Could Intelligent Speed Adaptation make overtaking unsafe?
This driving simulator study investigated how mandatory and voluntary ISA might affect a driver's overtaking decisions on rural roads, by presenting drivers with a variety of overtaking scenarios designed to evaluate both the frequency and safety of the manoeuvres. In half the overtaking scenarios, ISA was active and in the remainder ISA was switched off. A rural road was modelled with a number of 2 + 1 road sections, thus allowing drivers a protected overtaking opportunity. The results indicate that drivers became less inclined to initiate an overtaking manoeuvre when the mandatory ISA was active and this was particularly so when the overtaking opportunity was short. In addition to this, when ISA was activated drivers were more likely to have to abandon an overtaking, presumably due to running out of road. They also spent more time in the critical hatched area - a potentially unsafe behaviour. The quality of the overtaking manoeuvre was also affected when mandatory ISA was active, with drivers pulling out and cutting back in more sharply. In contrast, when driving with a voluntary ISA, overtaking behaviour remained mostly unchanged: drivers disengaged the function in approximately 70% of overtaking scenarios. The results of this study suggest that mandatory ISA could affect the safety of overtaking manoeuvres unless coupled with an adaptation period or other driver support functions that support safe overtaking
Deal or no deal: can incentives encourage widespread adoption of intelligent speed adaptation devices?
Given the burden of injury, economic, environmental and social consequences associated with speeding, reducing road traffic speed remains a major priority. Intelligent speed adaptation (ISA) is a promising but controversial new in-vehicle system that provides drivers with support on the speed-control task. In order to model potential system uptake, this paper explores drivers’ preferences for two different types of ISA given a number of alternative fiscal incentives and non-fiscal measures, using a stated preference approach. As would be expected with such a contentious issue, the analysis revealed the presence of significant variations in sensitivities and preferences in the sample. While a non-negligible part of the sample population has such strong opposition to ISA that no reasonable discounts or incentives would lead to them buying or accepting such a system, there is also a large part of the population that, if given the right incentives, would be willing or even keen to equip their vehicle with an ISA device
Managing nonuniformities and uncertainties in vehicle-oriented sensor data over next generation networks
Detailed and accurate vehicle-oriented sensor data is considered fundamental for efficient vehicle-to-everything V2X communication applications, especially in the upcoming highly heterogeneous, brisk and agile 5G networking era. Information retrieval, transfer and manipulation in real-time offers a small margin for erratic behavior, regardless of its root cause. This paper presents a method for managing nonuniformities and uncertainties found on datasets, based on an elaborate Matrix Completion technique, with superior performance in three distinct cases of vehicle-related sensor data, collected under real driving conditions. Our approach appears capable of handling sensing and communication irregularities, minimizing at the same time the storage and transmission requirements of Multi-access Edge Computing applications
Evaluating the effects of bilingual traffic signs on driver performance and safety
Variable Message Signs (VMS) can provide immediate and relevant information to road users and bilingual VMS can provide great flexibility in countries where a significant proportion of the population speak an alternative language to the majority. The study reported here evaluates the effect of various bilingual VMS configurations on driver behaviour and safety. The aim of the study was to determine whether or not the visual distraction associated with bilingual VMS signs of different configurations (length, complexity) impacted on driving performance. A driving simulator was used to allow full control over the scenarios, road environment and sign configuration and both longitudinal and lateral driver performance was assessed. Drivers were able to read one and two-line monolingual signs and two-line bilingual signs without disruption to their driving behaviour. However, drivers significantly reduced their speed in order to read four-line monolingual and four-line bilingual signs, accompanied by an increase in headway to the vehicle in front. This implies that drivers are possibly reading the irrelevant text on the bilingual sign and various methods for reducing this effect are discussed
Role of Multi-Wall Carbon Nanotubes on the main parameters of the Electrical Discharge Machining (EDM) process
Electrical discharge machining is a very accurate non-traditional manufacturing process for creating tiny apertures, complex shapes and geometries within mechanical parts and assemblies. Its performance is evaluated in terms of surface roughness, existence of cracks, voids and recast layer on the surface of product. The high heat generated on the electrically discharged material during the EDM process unfortunately decreases the quality of product. In this paper the high strength and unique electrical and thermal properties of multi-wall carbon nanotubes are used to improve the EDM performance when machining the AISI H13 tool steel, by means of copper electrodes. Material removal rate, electrode wear rate, surface roughness and recast layer were measured in presence of carbon nanotubes in the dielectric, then compared to the outcome of traditional EDM. Experiments show that mixing multi-wall carbon nanotubes within the dielectric makes the EDM more efficient, particularly if machining parameters are set at low pulse of energ
The activation of eco-driving mental models: can text messages prime drivers to use their existing knowledge and skills?
Eco-driving campaigns have traditionally assumed that drivers lack the necessary knowledge and skills and that this is something that needs rectifying. Therefore, many support systems have been designed to closely guide drivers and fine-tune their proficiency. However, research suggests that drivers already possess a substantial amount of the necessary knowledge and skills regarding eco-driving. In previous studies, participants used these effectively when they were explicitly asked to drive fuel-efficiently. In contrast, they used their safe driving skills when they were instructed to drive as they would normally. Hence, it is assumed that many drivers choose not to engage purposefully in eco-driving in their everyday lives. The aim of the current study was to investigate the effect of simple, periodic text messages (nine messages in 2 weeks) on drivers’ eco- and safe driving performance. It was hypothesised that provision of eco-driving primes and advice would encourage the activation of their eco-driving mental models and that comparable safety primes increase driving safety. For this purpose, a driving simulator experiment was conducted. All participants performed a pre-test drive and were then randomly divided into four groups, which received different interventions. For a period of 2 weeks, one group received text messages with eco-driving primes and another group received safety primes. A third group received advice messages on how to eco-drive. The fourth group were instructed by the experimenter to drive fuel-efficiently, immediately before driving, with no text message intervention. A post-test drive measured behavioural changes in scenarios deemed relevant to eco- and safe driving. The results suggest that the eco-driving prime and advice text messages did not have the desired effect. In comparison, asking drivers to drive fuel-efficiently led to eco-driving behaviours. These outcomes demonstrate the difficulty in changing ingrained habits. Future research is needed to strengthen such messages or activate existing knowledge and skills in other ways, so driver behaviour can be changed in cost-efficient ways
Driving simulator motion base right sizing
Driving simulator motion bases are available having various mechanisms and characteristics; among them, the synergistic 6DoF hexapod-type integrated with a sliding rail is the most commonly used. There is a large variety in workspaces (sizes) of both the hexapod and sliding rail used in research and training simulators, and there lacks consensus on what size of motion base is really needed in order to have high fidelity motion cueing. In this paper we introduce an approach that balances between having high fidelity motion cueing and at the same time addressing the minimum size requirement to reduce the purchase cost. A conventional classic motion cueing algorithm (MCA) is used together with an optimization method to establish the minimum workspace requirement, while meeting the fidelity criteria defined in literature. The right sizing requirements are driving task dependent, so in order to test this method, low and high motion-demanding driving tasks are tested using the experimental data collected from professional drivers. A standard (high) and a reduced (low) amount of tilt coordination is selected, showing how this defines a range of rail sizes to consider
Special issue in Transportation Research Part F: Traffic Psychology and Behaviour: The role of fitness to drive in traffic safety and mobility
Special issue in Transportation Research Part F: Traffic psychology and behaviour: The role of fitness to drive in traffic safety and mobility [Editorial
Revealing How Much Drivers Understand about Vehicle Pollutants: Towards Development of Information Campaigns
Thirty-four interviews were carried out with drivers in four countries to elicit their understanding about pollutants, specifically nitrogen dioxide (NOₓ) and particulate matter (PM). The
results showed that most of the participants knew that cars emitted carbon dioxide (CO₂), but they
were less aware of the emission of NOx and PM. Also, being aware of the negative impacts of
pollutants did not necessarily lead to eco-friendly vehicle choices. Most of the drivers were aware
of pollutant friendly behaviours such as avoiding harsh acceleration/deceleration and maintaining
smooth speed but were unaware of behaviours such as efficient gear use, avoiding engine idling, or
anticipation of traffic ahead. Only a few mentioned pre-trip or strategic level behaviours (e.g., vehicle
size/weight or the selection of appropriate routes and avoidance of traffic congestion). The results
could be used to design educational material to raise awareness and provide drivers with tips to
reduce their pollutant emissions
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