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In support of the Department of Energy ( DOE) "SuperTruck" program, a group of low energy, high output light emitting diode (LED) lamps were developed for forward lighting. Reduction of the energy needs of the truck by saving fuel and reducing CO₂ emissions are two of the goals of this program. In support of the energy reduction, a retrofit LED headlamp was designed, built and tested. The retrofit headlamp was switched from a halogen bulb to an LED-based system. The LED headlamp requires a new approach in heat management. The use of the LED, which is a 2π source, requires a different strategy in the optics from those used with a 4π source, like a traditional incandescent, halogen, or High Intensity Discharge (HID) light source. A thermal management system is necessary to facilitate the long life of the LED source. A unique method for removing the heat of the LED and maintaining an acceptable temperature was tested and reported.

Light Emitting Diodes (LEDs) are commonly used for signaling and marking functions on commercial vehicles. Recent work on new LED modules will allow the use of LEDs for illumination functions.

Today, LED automotive exterior lighting is already widely used on high end and upper middle class vehicles. We see already first examples of application as the standard lighting solution even in the mid class segment. A compact design and the feasibility of car life sealed solution is a strong argument to use LEDs for CHMSLs. Long lifetime and new styling opportunities speak for LEDS in front or rear position lights as well as in daytime running lamps;. Mainstream penetration of LED lighting solutions will first happen for functions where the benefits of LEDs have the highest positive impact and where this value can be realized in the most cost-effective way. During the different phases of the introduction of LEDs different requirements dominate the decision process. Providing unique styling opportunity and showing advanced technical functionality is leading for the early adopters.

The title of this paper fully indicates its scope. The author presents an intimate picture of conditions prevailing at the war front which affect the operation and maintenance of war trucks, and these two factors in turn indicate the trend that design should take. The training of the mechanical transport personnel of the Army is also gone into at some length. The English and American trucks used earlier in the war consisted of about nineteen different makes and forty-two totally different models, resulting in a very serious problem of providing spare parts and maintenance in general. In the British Army transportation comes under an Army Service Corps officer called the Director of Transport and Supplies. At the outbreak of the war these officers had had little mechanical experience, horses being employed principally. In the French Army motor vehicles were used to a greater extent before the war, under the artillery command.

With increased awareness and scrutiny of greenhouse gas (GHG) emissions, the heavy-duty truck industry is on the lookout for solutions that can maximize GHG savings, through either lowering fuel consumption and lowering methane slip. This paper focuses on whether it is possible to provide a differentiated Liquefied Natural Gas (LNG) that supports the further improvement of a High-Pressure Direct Injection (HPDI) Engine. Desired improvements from this LNG blend are the lowering or substitution of the pilot Diesel use of the current HPDI engine, the lowering of the raw exhaust gas methane concentration and any additional performance improvements. Sixty-five substances were identified that could potentially be blended into cryogenic methane thus creating a differentiated LNG fuel.

The maritime transportation sector is facing new international restrictions on exhaust emissions. NOx and SOx emissions from traditional marine fuels are a major challenge, which make natural gas a promising new clean alternative. Since the late 1980s, new concepts for medium-speed natural gas-fuelled engines have been developed, primarily for stationary power generation. This technology is currently entering the mobile sector, where Spark Ignition engines, Dual-Fuel engines and High Pressure Gas engines offer advantages such as high efficiency, low emissions and fuel flexibility. The availability of liquefied natural gas (LNG) is increasing, not least via small-scale distribution systems. In Norway, 23 coastal traffic vessels operate on LNG supplied by a distribution system that also supplies city bus fleets. This paper discusses the development of natural gas engines and fuel system technology, and describes experiences from LNG-fuelled ships in operation in Norway.

Spark plug heat range requirements, preignition limits, and ignition voltage requirements were investigated in several liquefied petroleum gas (LPG) fueled engines. These tests show that ignition voltage requirements both for cold starting and for running are considerably higher than with gasoline. It is also shown that very cold running spark plugs are both undesirable and unnecessary with LPG fuels. Spark plug design can be utilized to reduce voltage requirements and to improve the overall performance of these engines. Projected core nose type spark plugs may offer additional performance benefits in LPG tractor engines.

This paper provides a summary of a Liquefied Petroleum Gas (LPG) concept engine developed for medium duty applications (class 6-7 trucks) targeting high efficiency with a power density that matches turbocharged diesel engines. The turbocharged in-line 6 cylinder engine incorporates an advanced spark ignition combustion system design, a purpose built medium-duty class engine structure optimized for operation with a direct propane injection system, dual overhead cams with individual cam phasers and twin-entry turbocharger. The high tumble charge motion combustion system targeted for operation with direct injected (DI) LPG has resulted in an engine capable of producing up to 22 bar brake mean effective pressure (BMEP) at high brake thermal efficiency (BTE) throughout the operating map.

In this paper, considering the influence of longitudinal velocity on vehicle dynamics, an LPV (Linear Parameter Varying) model about longitudinal velocity is developed for the design of stability controller. A polytopic error dynamic model is developed and the weights for each vertex are selected. A robust gain scheduling control (RGSC) scheme based on an LPV model by controlling of the yaw moment is proposed to enhance vehicle stability especially in severe conditions. Some nonlinear numerical simulations are carried out on an 8-DOF nonlinear vehicle model for a J-turn manoeuvre and a lane-change manoeuvre respectively. The results demonstrate that considerable improvement in vehicle stability can be obtained by the RGSC controlled vehicle in a large range of longitudinal velocity compared with the conventional H∞ dynamic output-feedback controller and the uncontrolled vehicle.