Search Results

This paper described a survey that was designed to examine the seat discomfort and travel time factors for Dutch truck driver seat to reduce discomfort. Truck drivers were at risk of body discomfort for long hours sitting, and experience significant discomfort at different body parts. For the truck seat questionnaire, 217 Dutch truck drivers completed self administered questionnaires. Statistical methods were applied to analyze the surveys. Body discomfort level after one hour and five hours were studied. The outcomes from the analytical results were important and required more attention to reduce the body discomfort for long hour sitting.

Hydraulic power steering system, which can reduce the steering hand force by applying the output from a hydraulic actuator, has been widely used in vehicles. In this paper, a detailed steer model including steering column, steering trapezium, and detailed hydraulic power steering system which is consisting of steering cylinder, relief valve, rotary valve, pump and hydraulic lines were established, and a multi-body model of a heavy truck was established to connect with the hydraulic power steering system. Modelica simulation language, which can be efficiently used to investigate multi-domain problems, was used to in the modeling and simulation of the power steering system and the vehicle. The simulation was carried out to identify the effects of design variables on the lateral stability of the vehicle. The application of Modelica for investigating multi-domain problems is also demonstrated.

On-center handling is one of the most important test conditions which are used to evaluate the handling performance of both passenger cars and commercial vehicles. This paper aims at investigating and verifying the influence of parameters on on-center handling of articulated trucks. A full vehicle model, including the steering system, suspension system, cab, frame, trailer and so on, was established in first by measuring the parameters of each component. The comparison of simulation and test results shown that the simulation precision of the vehicle model was up to 80%. Based on the model, the influence analysis of parameters, such as stiffness of steering drag link, steering ratio, kingpin friction, were carried out and were verified through the handling test. The analysis results indicated that larger stiffness of steering drag link, smaller gear ratio could enhance the steer sensitivity and steer stiffness, small kingpin friction is beneficial to the steering return ability.

Ride comfort is simply defined as the vibration performance of the vehicle which is excited by road surface roughness, generally as the vehicle moves at specific constant velocity over the road profile. Ride comfort was an important index for heavy truck, due to long distance transfer and long time driving. In order to improve the ride comfort of a heavy truck, a detailed model, including flex frame, chassis suspension, cab suspension, powertrain, etc., was built and assembled by MSC.ADAMS software. Simulation and testing data were consistent very well, which showed the correctness of the model. The optimization of chassis and cab suspension including the stiffness of the leafspring, the damping of the shock absorber, etc. was carried out to improve the ride comfort of the vehicle. The ride comfort testing was carried out on the proving ground to verify the effectiveness the optimization results. The testing results shows that the ride comfort has been improved after tuning.

The stiffness of the frame has a great influence on the ride comfort of the heavy truck. Reducing frame thickness was proved to be unacceptable in terms of ride comfort, which is verified by the testing results. The truck frame was reinforced in order to improve the ride comfort. The modal analysis showed that the pitch frequency of the vehicle has increased 0.5 Hz and the frequency response has decreased by 20%. In order to research the influence of frame stiffness on the heavy truck ride comfort, a detailed model including a flex frame, chassis suspension, cab suspension, driveline, etc., was built by MSC.ADAMS. The Simulation results showed that the ride comfort can be improved by reinforce the frame, and the ride comfort can be improved by 5%∼10%. The results of this study need to be further examined through field testing.

To better understand the technical challenges of commercial vehicle electrification, BorgWarner converted a production Internal Combustion Engine (ICE) medium duty truck into a fully electrified vehicle. The resulting vehicle includes a newly developed dual-motor rear Beam eAxle driven by a pair of high-performance silicon carbide (SiC) inverters, an 800V battery system, and a new thermal management system customized for the electric vehicle. This paper will detail the conversion process along with the key components involved in the build. The resulting performance of the fully electrified commercial vehicle will be presented in comparison to the original production vehicle. The primary aim is to outline what is entailed in an electric vehicle conversion and to share the learnings gained throughout this build and development process.