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Hybrid electric vehicles (HEVs) are worldwide recognized as one of the best and most immediate opportunities to solve the problems of fuel consumption, pollutant emissions and fossil fuels depletion, thanks to the high reliability of engines and the high efficiencies of motors. Moreover, as transport policy is becoming day by day stricter all over the world, moving people or goods efficiently and cheaply is the goal that all the main automobile manufacturers are trying to reach. In this context, the municipalities are performing their own action plans for public transport and the efforts in realizing high efficiency hybrid electric buses, could be supported by the local policies. For these reasons, the authors intend to propose an efficient control strategy for a hybrid electric bus, with a series architecture for the power-train.

Two new 4 X 4 drivetrain systems have been developed for highway tractors that are used to pull multiple trailer combinations. The first one is a 4 X 2 that automatically becomes a 4 X 4 when conditions exist that require 4 X 4 operation. The second one is a full-time 4 X 4 that proportions the drive torque 36% to the front axle and 64% to the rear axle. A unique front driving steering axle has also been developed that permits a 4 X 4 system to be installed in a standard 4 X 2 truck. There is no need to relocate any major components to make space available for a front driving steering axle.

In the recent years, Electric-mobility has been a trending aspect in the transportation sector. Increase in the air pollution by the use of combustion vehicles resulted in the initiation of various subsidiaries and norms by the governments across the world. To bring an eco-friendly transportation, many cities across the world are trying to incorporate the electric vehicles in the public transportation system. In India, State Road Transport Undertakings (SRTU’s) have started adopting electric buses. One of the critical requirement for successful operation of electric vehicles is charging infrastructure, which is required for charging the vehicles. There are various charging technologies available in the industry. This paper presents a case study for evaluating pantograph based electric bus charging systems for Patna project and compares the charging schedule, charger infrastructure sizing, CAPEX and OPEX with respect to traditional proven CCS2 charging technology.

Regulatory requirements in the European Union (EU) for off-road machines and road vehicles are different. Vehicles which transport passengers and goods, along with attached trailers, as well as road motorcycles must meet EEC type-approval requirements. All other types of self-propelled machines must meet the requirements of the Machinery Directive (Council Directive 98/37/EC), and the Electromagnetic Compatibility (EMC) Directive (Council Directive 89/336/EEC) and possibly other directives. This includes such categories as agriculture and forestry machines, construction machines, industrial trucks and similar products. The various directives outline the different processes for demonstrating compliance with the EU requirements. The intent of this paper is to summarize a few of the requirements that are of interest to off-highway equipment manufacturers and to identify some sources of information about the regulatory requirements.

Truck platooning is an emerging technology that exploits the drag reduction experienced by bluff bodies moving together in close longitudinal proximity. The drag-reduction phenomenon is produced via two mechanisms: wake-effect drag reduction from leading vehicles, whereby a following vehicle operates in a region of lower apparent wind speed, thus reducing its drag; and base-drag reduction from following vehicles, whereby the high-pressure field forward of a closely-following vehicle will increase the base pressure of a leading vehicle, thus reducing its drag. This paper presents a physics-guided empirical model for calculating the drag-reduction benefits from truck platooning. The model provides a general framework from which the drag reduction of any vehicle in a heterogeneous truck platoon can be calculated, based on its isolated-vehicle drag-coefficient performance and limited geometric considerations.

The Nexus vehicle was designed and built for Transport Canada at the University of Saskatchewan to demonstrate that a safety compliant single passenger commuter vehicle could attain extremely low fuel consumption rates at modest highway speeds. Experimentally determined steady state fuel consumption rates of the Nexus prototype ranged from 1.6 L/100 km at 61 km/hr up to 2.8 L/100 km at 121 km/hr. Fuel consumption rates for the Society of Automotive Engineers (SAE) driving cycle tests were 4.5 L/100 km for the SAE Urban cycle and 2.0 L/100 km for the SAE Interstate 55 cycle. The efficiency of the power train was determined using a laboratory dynamometer, enabling the road test results to be compared to the results from an energy and performance simulation program. Predicted fuel economy was in good agreement with that determined experimentally. Widespread use of single passenger commuter vehicles would substantially reduce current transportation energy consumption.

Edinburgh is one of the fastest growing and most prosperous cities in the United Kingdom. This success has brought with it the problems of traffic congestion and pollution. The Edinburgh Metro would use the city's disused railway heritage combined with modern light rail technology to provide a popular and sustainable transport system. When this proposal was originally submitted in 1999, it seemed a worthwhile but distant possibility. However, in October 2001 and March 2002, the Scottish Executive announced preliminary funding packages that mean that significant progress is now likely. The planned system could be operating by 2009.

Highway and roadway surface measurement is a practice that has been ongoing for decades now. This sort of measurement is intended to ensure a safe level of road perturbances. The measurement may be conducted by a slow moving apparatus directly measuring the elevation of the road, at varying distance intervals, to obtain a road profile, with varying degrees of resolution. An alternate means is to measure the surface roughness at highway speeds using accelerometers coupled with high speed distance measurements, such as laser sensors. Vehicles out rigged with such a system are termed inertial profilers. This type of inertial measurement provides a sort of filtered roadway profile. Much research has been conducted on the analysis of highway roughness, and the associated metrics involved. In many instances, it is desirable to maintain an off-road course such that the course will provide sufficient challenges to a vehicle during durability testing.

A wide variety of computer and communications technology vendors currently in the marketplace offer technologies, products and services designed to streamline regulatory processes and improve operational efficiency for trucking companies. The goods and services are sold based on their “functional attributes” and the cost is a direct function of the nature of the application and the carrier's needs. The Federal Highway Administration (FHWA) Intelligent Transportation Systems/Commercial Vehicle Operations (ITS/CVO) User Services are “bundles” of functional services envisioned by the FHWA to help advance the overall objectives of improved operational efficiency of our nation's roadways and servicing of the commercial vehicle population. Because many of the technology applications are still in the development stage, a framework has been developed to assess the future hypothetical benefits and costs of the ITS/CVO User Services Program.

Platooning is a key research area where increased focus and interest is shown in order to maximize the transport efficiency of road vehicles. Although the key benefits are projected as increased fuel efficiency especially when it comes to commercial vehicles, allied benefits such as convoy pack efficiency, traffic throughput rate, increased life cycle of components and a source of monetary benefit when using a subscription model are areas which need to be explored. Existing literature points to control strategies predominantly focused on longitudinal control and traffic management in bottlenecks.

Overloading of trucks can easily cause damage to roads, bridges and other transportation facilities, and accelerate the fatigue loss of the vehicles themselves, and accidents are prone to occur under overload conditions. In recent years, various countries have formulated a series of management methods and governance measures for truck overloading. However, the detection method for overload behavior is not efficient and accurate enough. At present, the method of dynamic load identification is not perfect. No matter whether it is the dynamic weight measurement method of reconstructing the road surface or the non-contact dynamic weight measurement method, little attention is paid to the difference of different vehicles. Especially for different vehicles, there should be different load limits, and the current devices are not smart enough.

Prior to World War II, most heavy duty highway trucks and tractors were built as Conventionals, i. e., with the cab mounted behind the engine. In the late 1940's cab-over-engine types gained acceptance and in the 1950's the tilt cab COE was developed in its present form including sleeper cabs. The new concept is to combine the best features of conventionals and tilt cab COEs to develop a superior non-sleeper tractor that makes no compromises for sleeper cab types.

Road test simulation on test rig is widely used in the automobile industry to shorten the development circles. However, there is still room for further improving the time cost of current road simulation test. This paper described a new method considering both the damage error and the runtime of the test on a multi-axial test rig. First, the fatigue editing technique is applied to cut the small load in road data to reduce the runtime initially. The edited road load data could be reproduced on a multi-axial test rig successfully. Second, the rainflow matrices of strains on different proving ground roads are established and transformed into damage matrices based on the S-N curve and Miner rules using a reduction method. A standard simulation test for vehicle reliability procedure is established according to the proving ground schedule as a target to be accelerated.

Due to the variability of real traffic conditions for vehicle testing, real-world vehicle performance estimation using simulation method become vital. Especially for heavy duty vehicles (e.g. 40 t trucks), which are used for international freight transport, real-world tests are difficult, complex and expensive. Vehicle simulations use mathematical methods or commercial software, which take given driving cycles as inputs. However, the road situations in real driving are different from the driving cycles, whose speed profiles are obtained under specific conditions. In this paper, a real-world vehicle performance estimation method using simulation was proposed, also it took traffic and real road situations into consideration, which made it possible to investigate the performance of vehicles operating on any roads and traffic conditions. The proposed approach is applicable to all kind of road vehicles, e.g. trucks, buses, etc. In the method, the real-road network includes road elevation.

A one thousand horsepower machine to be used for milling and excavating concrete and asphalt pavement is currently being produced. The machine was designed primarily for large pavement removal or surface texturing jobs. This paper contains general description of the machine, its overall size, power distribution, drive configuration, etc. It is significant that the machine represents a proven, quick economically sound method of resurfacing, recycling, restoring and reclaiming our nations deteriorating highway system.

Overturning on a road turn has always been a problem in vehicles. Based on a half- vehicle model, the results of vehicle stability after incorporating a hydraulic-actuator system is analyzed. It has been shown in the paper that the stability of a vehicle on a road turn can be increased promisingly by tilting its body towards the inner direction. The results are compared with the corresponding results of a conventional vehicle. Because of the feasibility and effectiveness of the proposed algorithm, the above system shows a definite improvement in vehicle stability.

The high gravity center of the concrete mixer truck reduces the truck’s stability while steering. The rolling stirring tank makes the stability even worse than the regular engineering vehicle due to the dynamic variation of the centroid position. Most of the researches on the rollover stability of concrete mixer trucks focus on the rollover model establishment and dynamic simulation module. The change of concrete centroid is ignored when the safety cornering speed is calculated. This paper proposes a pre-warning method for the cornering speed of concrete mixer trucks based on centroid dynamic simulation. In the method, the mixing tank stirring model and the vehicle driving dynamic model are established on the Fluent and TruckSim simulation platforms, respectively. The theoretical speed threshold obtained by simulation is used as the evaluation index of the warning speed in the curve. Firstly, the dynamic simulation of the stirring tank model is carried out by Fluent.

Fuel cell engines are expected to deliver greater efficiency and lower emissions than conventional transit bus powertrains in the near future. Although experimental vehicles have demonstrated the emission and efficiency benefits of fuel cell power, the next step toward implementation is widespread fleet demonstrations to prove the technology in the field. In order to aid in the start of new demonstrations and speed fuel cell technology towards the fleet vehicle marketplace, an assessment of the needs, risks, and advantages of using fuel cell power must be obtained from a consumer perspective. It has been assumed that the increased fuel efficiency that is inherent to fuel cell systems will lower operating costs as compared with conventional diesel powertrains. A comparison of two fuel cell buses and a diesel bus was completed in order to quantify the operational cost benefits and identify potential cost deterrents to fuel cell bus implementation.

For years, producers of low to medium volume products of high unit cost have been faced with the questions-“How much do we test?” and “What if we don't?” Today, manufacturers cannot compete in the market if these questions are not answered. This paper presents a methodology for answering these questions quantitatively. It applies Bayes Theorem of “apriori knowledge” to generate a probabalistic model of the new product testing task. It uses the existing knowledge and expertise within the organization and a simple matrix technique to determine the testing needs for the project at hand. This paper is intended to address the issues of durability and reliability of new products that are manufactured in relatively low volumes, such as Lift Trucks and Farm Equipment and/or products of high unit cost such as construction or off highway machinery.