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Advanced traveller information systems (ATIS) play a very vital role in improving traffic conditions on the roads, by providing information for drivers to assist them in making more informed travel decisions. Drivers' perceptions towards ATIS mostly define these responses. This paper examines how the use of and familiarity with different sources and media of real time traffic information updates may affect drivers' perceptions, thereby determining their responses to ATIS technology. The study employs a hybrid discrete choice model that considers interactions between latent perception and the sources of traffic information sought. Data used in this study was collected through a survey conducted among a sample of 500 commuters who use Highway 2 (Deerfoot Trail) in Calgary, Alberta, Canada. In the case of major delays due to accidents or construction on Highway 2, the City of Calgary is using 12 variable message signs (VMS) to divert drivers to alternative parallel arterials. The developed integrated discrete choice and conditional latent variable model clearly identifies an important link between the propensity to comply with VMS information and the use of other traffic information sources. One of the primary findings of this study is the existence of a significant correlation between radio traffic information, TV traffic information, and VMS displays. It was found that drivers who listen to radio traffic information or watch TV traffic channels are more likely to be compliant with VMS messages, in terms of route diversions and changes in trip destinations. Key words: ATIS, VMS, pre-trip and en route traffic information, driver response, driver perception, hybrid discrete choice. Les systemes avances d'information aux voyageurs (ATIS) jouent un role essentiel dans l'amelioration des conditions routieres, en fournissant de l'information aux conducteurs afin de les aider a prendre des meilleures decisions de deplacement. Les perceptions des conducteurs par rapport a l'ATIS definissent clairement ces reactions. Le present article examine la maniere dont l'utilisation et la familiarite avec differentes sources et differents medias de mise a jour d'information routiere en temps reel peuvent affecter les perceptions des conducteurs, determinant ainsi leur reaction a la technologie ATIS. L'etude utilise un modele de choix discret hybride qui tient compte des interactions entre la perception latente et les sources d'information routiere recherchee. Les donnees utilisees dans la presente etude ont ete colligees lors d'un sondage realise aupres de 500 navetteurs qui utilisent l'Autoroute 2 (Deerfoot Trail) a Calgary, Alberta, Canada. Dans le cas de retards importants causes par des accidents ou de la construction sur l'Autoroute 2, la Ville de Calgary utilise 12 panneaux a messages variables (PMV) pour diriger les conducteurs vers des d'autres arteres paralleles de detour. Le choix discret integre qui a ete developpe ainsi que le modele de variables latentes conditionnelles identifient clairement un lien important entre la propension a se conformer a l'information des PMV et l'utilisation d'autres sources d'information routiere. L'une des conclusions principales de la presente etude est l'existence d'une correlation importante entre l'information routiere a la radio, l'information routiere a la television et les affichages sur les PMV. Il a ete trouve que les conducteurs qui ecoutent l'information sur les conditions routieres ou regardent les postes de television presentant les conditions routieres suivent plus probablement les messages PMV en ce qui concerne les detours et les changements dans les destinations des deplacements. Mots-cles : ATIS, PMV, information routiere avant deplacement et en route, reaction des conducteurs, perception des conducteurs, choix discret hybride. [Traduit par la Redaction], 1. Introduction The application of ITS (intelligent transportation system) and ATIS (advanced traveller information system) technologies are mostly intended to influence travellers' trip-making behaviours, to use the transportation system efficiently, [...]

This paper proposes a new electric power steering control strategy, which significantly reduces the effort needed to change the steering direction of stationary vehicles. Previous attempts to reduce undesirable steering vibration have failed to reduce the steering torque because high-assist gains tend to produce oscillation or increase noise sensitivity. Herein, to eliminate this vibration, a new control strategy was developed based on pinion angular velocity control using a newly developed observer based on a simplified steering model. Tests yielded excellent estimations of the pinion angular velocity, and this made it possible to eliminate vibration at all steering wheel rotation speeds. Experiments with a test vehicle confirmed significant steering torque reduction, over a wide range of steering wheel speeds, without vibration transmission to the driver. The proposed control strategy allowed use of an assist gain more than three times higher than is conventional. Additionally, the proposed control strategy does not require supplemental sensors. [DOI: 10.1115/1.4001838] Keywords: automotive engineering, mechanical modeling, electric power steering, motor control, vibration control

We present a closed-loop approach to solve the semiautonomous nonholonomic vehicle-parking assistant problem. The method allows for a priori unknown and potentially high vehicle speeds and dynamic environment variations. The computationally low-cost, memory-efficient algorithm respects constraints on the steering angle and its first two derivatives, allowing for comfortable, safe, and smooth steering motions. A parking situation is captured by an arrangement of precalculated vector fields of feasible nonholonomic paths, by which the vehicle is controlled toward a desired goal configuration inside a parking bay. Using standard onboard environment perception sensors, the system adapts to changes in the environment and avoids collisions whenever possible, without aborting a parking procedure. Index Terms--Collision avoidance, driver-in-the-loop, non-holonomic, semi-autonomous, vehicle motion planning, vehicle parking.

Right-turn lanes are used to provide space for the deceleration and storage of turning vehicles and to separate the turning vehicles from the through movement. When larger corner radii are used at the right turn, vehicles can turn at higher speeds (thereby minimizing speed differential between turning and through vehicles). A concern with the higher operating speed is the challenge it provides pedestrians. This project analyzed the impact of right-turn treatments on right-turn vehicles speeds at 19 urban approaches. Each approach had an exclusive right-turn lane that was separated from the through lane with either a lane line or a raised corner island. The 85th percentile free-flow speed near the middle of the right turn ranged from 20.9 to 33.8 km/h (13-21 mi./h) while on the approach it ranged from 27.4 to 46.7 km/h (17-29 mi./h). Speed prediction equations were developed as part of this study. CE Database subject headings: Traffic speed; Statistics; Urban areas; Predictions.

Byline: M. Abdollahi, O.A. Olatunbosun The work reported here describes the results of a series of parameter studies to investigate the relative effects of varying each suspension component parameter on vehicle ride comfort. The vehicle sprung mass was identified as having a significant effect on the overall ride index. A methodology is prescribed by which the ride performance of a vehicle with a passive suspension arrangement could be maintained at a predetermined limit irrespective of the vehicle load condition by suitable design of the suspension strut rubber mounts.

Nurses using their cars for work could receive an extra 20 pence per mile towards petrol costs if NHS proposals to match Automobile Association (AA) recommendations are agreed. At present [...]