Search results for "Automotive engineering"
showing 10 items of 483 documents
The Constraints of Vehicle Range and Congestion for the Use of Electric Vehicles for Urban Freight in France
2015
The 9th International Conference on City Logistics, Tenerife, Espagne, 17-/06/2015 - 19/06/2015; Electric vehicle is a solution to reduce pollutant emissions from road urban freight. This paper assesses the potential CO2 reduction by transferring urban freight from diesel to electric vehicles while simultaneously looking at the two main technical constraints: electric vehicle range and the impact on congestion linked to change diesel heavy duty vehicles (with a load up to 25 tons) to much smaller electric vehicles. The data used has been computed from a survey (ECHO) that describes in details a very large sample of French shipments. Two scenarios were set up, which differ mainly by the type…
Design of a new high energy rear underrun protective device
2008
In recent years the vehicle design field has followed a progressive evolution by focusing its main interest on passive and active safety levels. One of the most injurious cases for the safety of passengers is the crash between a car and a heavy vehicle (truck). Generally, in fact, when such an occurrence happens, the greatest damage is suffered by the passengers of the car. This is because of the considerable structural difference between the two vehicles and the lack of devices to reduce the injuries of the car passengers. In this work, as a consequence of the previous considerations, we deal with the design of a new protective system for heavy vehicles over 3.5 tons. The new rear underrun…
Public acceptance of semi-automated truck platoon driving. A comparison between Germany and California
2020
Abstract Platooning technology aims at achieving fuel savings by reducing the distance between two or more electronically coupled vehicles. This technology has recently been tested on public highways with heavy trucks in Germany and California. The objective of this study is to assess the level of acceptance among other road users as well as influencing factors of acceptance. An online questionnaire was administered in Germany and California with a total of N = 536 participants. They received information about truck platoon driving (level-1 and level-2 automation) and answered questions about their attitudes towards the technology as well as their behavioral intention to cooperate with the …
The self-reported causes of sleepiness in shift-working tram and truck drivers
2021
Identifying the causes of sleepiness in various safety-critical work environments is neces-sary for implementing more efficient fatigue management strategies. In transportation, little is known about drivers' own perceptions of these causes. Therefore, we instructed shift-working tram (n = 23) and long-haul truck drivers (n = 52) to report at the end of their shifts what made them sleepy if they felt so. These self-reports, measured on-duty sleepiness, and sleep amounts were recorded on every shift over a period of 2-3 weeks per driver. The causes of sleepiness were queried with smartphone applications and sleep logs. Sleepiness was measured with the Karolinska Sleepiness Scale (KSS) and sl…
Passenger Car Equivalent for Heavy Vehicles Crossing Turbo-roundabouts
2016
Abstract Turbo-roundabouts represent an innovative scheme of modern roundabouts which provides a spiraling traffic flow and requires drivers to choose their direction before entering the intersection, since raised lane separators mark the lanes on the ring. The configuration of the turbo-roundabout makes that patterns of conflict at entries with one and two conflicting traffic streams can coexist. This paper presents research efforts aimed at measuring quantitatively the effect of heavy vehicles on operational conditions of a turbo-roundabout. The study starts from the initial belief that the greatest constraints to the vehicular trajectories imposed by the turbo-roundabout necessarily impl…
Exploiting Valve Timing for Pneumatic Energy Savings
2018
This research paper aims at addressing solutions that reduce air consumption in generic pneumatic systems used for pick-and-place operations. The investigation considers different system architectures both with a single control valve and two control valves arranged according to an independent metering configuration. Suitable control strategies are then proposed exploiting multiple timings to shut off the non-proportional switching valve(s). The resulting scenarios are experimentally evaluated on a dedicated test-bed. The main conclusion is that reduction of air consumption up to 73% is possible in comparison to the state-of-the-art layout for the reference application. Numerical simulations…
Network Slicing Enabled Resource Management for Service-Oriented Ultra-Reliable and Low-Latency Vehicular Networks
2020
Network slicing has been considered as a promising candidate to provide customized services for vehicular applications that have extremely high requirements of latency and reliability. However, the high mobility of vehicles poses significant challenges to resource management in such a stochastic vehicular environment with time-varying service demands. In this paper, we develop an online network slicing scheduling strategy for joint resource block (RB) allocation and power control in vehicular networks. The long-term time-averaged total system capacity is maximized while guaranteeing strict ultra-reliable and low-latency requirements of vehicle communication links, subject to stability const…
Energy-Efficient Edge Computing Service Provisioning for Vehicular Networks: A Consensus ADMM Approach
2019
In vehicular networks, in-vehicle user equipment (UE) with limited battery capacity can achieve opportunistic energy saving by offloading energy-hungry workloads to vehicular edge computing nodes via vehicle-to-infrastructure links. However, how to determine the optimal portion of workload to be offloaded based on the dynamic states of energy consumption and latency in local computing, data transmission, workload execution and handover, is still an open issue. In this paper, we study the energy-efficient workload offloading problem and propose a low-complexity distributed solution based on consensus alternating direction method of multipliers. By incorporating a set of local variables for e…
A Computational Approach to Vibration Control of Vehicle Engine-Body Systems
2012
In recent years, the noise and vibration of cars have become increasingly important [20, 23, 29, 30, 35]. A major comfort aspect is the transmission of engine-induced vibrations through powertrain mounts into the chassis (see Figure 1). Engine and powertrain mounts are usually designed according to criteria that incorporate a trade-off between the isolation of the engine from the chassis and the restriction of engine movements. The engine mount is an efficient passive means to isolate the car chassis structure from the engine vibration. However, the passive means for isolation is efficient only in the high frequency range. However the vibration disturbance generated by the engine occurs mai…
Survey of the Working Condition of Used Tractors in Northern Italy
1995
The working condition of 96 used tractors of different ages and sizes was examined in Northern Italy and compared with those of new machines and the standards at present in force. The results show that from the safety point of view, performance levels do not worsen drastically with increase in vehicle age. Rusty roll-over protective structures with cracks and tears are the main danger. Controls which are difficult to operate, seats in very bad condition, high levels of noise and vibrations render the situation critical from the ergonomic point of view.