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CHEVROLET has made its new air-suspension system easily interchangeable in production line assembly with standard full-coil suspension by adopting a 4-link-type rear suspension with short and long arms. A feature of the system is the mounting of the leveling valves within the air-spring assemblies. These valves correct riding height continually at a moderate rate, regardless of whether the springs are leveling or operating in ride motion. The system provides constant frequency ride—ride comfort remains the same whether the car is occupied by the driver alone or is fully loaded.

The environment is one of the most important issues currently facing the world and the automobile industry is required to respond with eco-cars. To meet this requirement, the hybrid vehicle is one of the most optimal solutions. The hybrid system automatically stops engine idling (idling stop), or stops the engine during deceleration to recover energy. The engine stop however creates a problem concerning the vehicle's climate control system. Because the conventional climate control system incorporates a compressor driven by engine belt, there is almost no cooling performance while the engine is stopped. Until now, when a driver needed more cooling comfort the engine has been switched back on as a compromise measure. To realize cabin comfort that is consistent with fuel saving, a 2-way driven compressor has been developed that can be driven both by engine belt while the engine is running and by electric motor when the engine is stopped.

The demands for comfort and a cleaner environment have been increasing for the past years for motorcycle as well as car manufacturers. With the need to decrease the time-to-market, there is a clear drive to apply CAE-based methods in order to evaluate new designs and to propose design changes that solve any identified problems. More specifically, the demands on the comfort of the rider are not only related to ride & handling and vibration levels(1), but also to the noise levels generated by the motorcycle. This paper presents the virtual modeling of one-cylinder engine of a motorcycle that identifies the mechanism behind the generation of an annoying noise. Furthermore, different possible design changes were evaluated in order to solve the problem. A combined experimental and numerical approach was followed to achieve this. Experiments were used to identify important parameters that determine the engine behavior and thus are critical for the modeling of such an engine.

In order to improve the fit and comfort of helmets, we developed digital head models that represent the anthropometric and morphometric variability found in the U.S. Navy. We analyzed the size and shape variation using two related approaches. First, we used Procrustes superimposition, which minimizes the distances between all landmarks of all subjects. This allowed us to visualize the variation in landmark distribution of the face and to test for statistical differences. Second, we extracted curvatures along the surface of the head. This allowed us to characterize the variation in the shape of the head. To create a series of sized digital models, we used principal component analysis (PCA) to organize the variation in both the traditional measurements as well as the locations of the 3D landmarks. Using an adaptation of multivariate accommodation modeling we identified representative individuals who characterize 95% of the variation in size and shape.

The vehicle Heating, Ventilation and Air conditioning (HVAC) system is designed to meet both the safety and thermal comfort requirements of the passengers inside the cabin. The thermal comfort requirement, however, is highly subjective and is usually met objectively by carrying out time dependent mapping of parameters like the velocity and temperature at various in-cabin locations. These target parameters are simulated for the vehicle interior for a case of hot soaking and its subsequent cool-down to test the efficacy of the AC system. Typically, AC performance is judged by air temperature at passenger locations, thermal comfort estimation along with time to reach comfortable condition for human. Simulating long transient vehicle cabin for thermal comfort evaluation is computationally expensive and involves complex cabin material modelling.

Today's agri-businessman is challenged to improve his efficiency to meet higher operating costs and to counter the effects of inflation. New concepts in John Deere's line of 4-wheel-drive tractors are targeted toward this goal and provide increased productivity through power increases, improved fuel economy, comfortable convenient operator environment and controls, increased hydraulic power, improved serviceability and repairability and monitoring of more critical vehicle functions.

Electrical Air Conditioning Systems for 42 V vehicles will provide many benefits in terms of Environment protection, car Architecture, cabin Comfort and overall Safety. E-A/C Systems essentially differ from conventional ones by the use of electrical compressors. First of all, they will be particularly well adapted to new powertrains, helping to make them more environmentally friendly. Accurate control and high efficiency under the most common thermal conditions will reduce the A/C impact on fuel consumption. Besides, higher sealing integrity will cut emissions of refrigerant during normal operation and maintenance. Secondly, the use of an electrically driven compressor (EDC) will suppress a belt, and will reduce the packaging constraints. This will help to design new vehicle architectures. Thirdly, the electrification of air conditioning will allow better thermal comfort. In particular, E-A/C Systems provide a good opportunity for cabin pre-conditioning.

A new compact skid steer loader has been developed. Along with productivity and cost, the design of this loader was concentrated on improving ease of operation, operator comfort and safety, and serviceability. This paper discusses how serviceability was improved over previous model Bobcats. That is; improved accessibility to regulary serviced items, reduced service parts and improved reliability.

Weight reduction and high transmission efficiency demands are getting heavier to manual transmission (MT) for vehicle driving and fuel economy performance. Also comfortable shift feeling and low gear noise level are continuously required by customer because those sensitivity performances are directly recognized by driver which can determine the transmission's merchantability. Newly developed high torque capacity MT is based on serial transmission BG6 which is adopted into a lot of customer' vehicle. This new MT is weight reduced, shift feeling and gear noise performance are highly improved that keeps strong competitiveness in the future. Concerning shift feeling, its smoothness, force balance and cross shift performance are improved and optimized. Also for low gear noise performance, it was reduced to the level which can have advantage to competitor and highly comfortable for passenger vehicle. Those improvement technologies are reported as follows.

This paper gives a report on ergonomic approaches we tried to scooters for improvements in their riding comfort. First we conducted investigations into riding postures that offer a comfortable scooter ride. That is, we picked out major items for the evaluation of scooter riding postures and investigated a correlation between those items and their physical quantities. Our investigation revealed that room for leg and arm movements played a major role in a scooter riding posture. We further found out a high correlation between the evaluation items for legroom and the knee angles and also high correlation between the evaluation items for legroom and the ankle angle. Next we report on the result of the attempt we made at improved riding comfort by equipping the scooter seat with a backrest. To check the effects of backrest, we measured the seating pressure distribution, myogenic potential, and cardiogenic potential.

The 70 Series 4WD tractors offered by John Deere has been replaced by a new 9000 product line as part of the continuous improvement process to meet customer needs and provide a product with maximum value to our customers. The new model lineup is 260, 310, 360, and 425 engine HP. All models are powered by John Deere engines with the largest 3 models using the new 10.5L and 12.5L engines. The new line of 9000 Series tractors is a styled tractor family which uses many of the 8000 Series Row Crop tractor concepts and designs. This new product line provides improved operator comfort, enhanced operator conveniences, and simplified serviceability.

The automobile body industry in Indonesia is developed by the needs of motorized means of transportation, especially for passengers cheap enough to meet the consumer's buying power. To fill these needs, modifications on commercial vehicles into passenger vehicles or provisions for passenger space on special chassis had been carried out. It can be seen that basically body construction or modification in the automobile body industry is but an extension of the automobile industry in general. At present, commercial vehicles are designed to run with higher speeds and lower fuel consumption. This situation calls for a structure design that has to meet specifications generally applied to automobiles, so as to enable it to perform equally well with the basic vehicles.

The vision of SESAR is to integrate and implement new technologies to improve air traffic management (ATM) performance. Enhanced automation and new separation modes characterize the future concept of operations, where the role of the human operator will remain central by integrating more managing and decision-making functions. The expected changes represent challenges for the human actors in the aircraft and on ground and must be taken into account during the development phase. Integrating the human in the ATM system development starting from the early design phase is a key factor for future acceptability. This paper describes the adaptation of currently applied Cockpit Human Factors processes in order to be able to design the aircraft for the future ATM environment.

In this paper the first results of a project, initiated in the University of Coimbra and dealing with the conjugated influence of multiple stressors in riding passengers, are presented. A field study was conducted in public transportation buses, in which the subjective response of the occupants was collected and the physical parameters related to thermal comfort, air quality, vibration and noise were acquired. More than 250 responses to a subjective inquire were collected. Besides questioning the occupants about how they felt the different stressors, the questionnaires also have a final question related to how they felt the global comfort of the vehicle, in a five-point scale. Even if it looks too far, the final goal of this project is to obtain an general comfort index that takes into account the influence of multiple stressors, thus giving to vehicle manufacturers a tool to evaluate the performance of their models and to improve the vehicle friendliness to passengers.

A new concept in communications for the motorist called DAIR for Driver Aid, Information, and Routing is described. It is designed to assist the driver with his peripheral functions so that he can concentrate his attention on driving. DAIR automatically gives routing instructions, communicates traffic signs and roadside messages, and provides a radio link to call for emergency assistance or information. The system is cooperative between the motorist and the road authority but is independent of other motorists. Demonstration hardware has been designed around the Citizens Band to take advantage of the mobile transceivers already in service. DAIR can be implemented in a building block fashion using the CB transceiver as the basic component.

Abstract Vehicle-to-infrastructure (V2I) connectivity technology presents the opportunity for vehicles to perform autonomous longitudinal control to navigate safely and efficiently through sequences of V2I-enabled intersections, known as connected corridors. Existing research has proposed several control systems to navigate these corridors while minimizing energy consumption and travel time. This article analyzes and compares the simulated performance of three different autonomous navigation systems in connected corridors: a V2I-informed constant acceleration kinematic controller (V2I-K), a V2I-informed model predictive controller (V2I-MPC), and a V2I-informed reinforcement learning (V2I-RL) agent. A rules-based controller that does not use V2I information is implemented to simulate a human driver and is used as a baseline. The performance metrics analyzed are net energy consumption, travel time, and root-mean-square (RMS) acceleration.

Vehicle Dynamics testing has its importance in the fields of benchmarking and the validation of mathematical models built in order to predict the ride performance of the vehicle. The importance of enhancing the ride comfort is increasing day by day in present day scenario because of the long hours of driving experience. In presented work, the ride testing is done for two hatchback vehicles on highway conditions in order to compare the ride quality and ride comfort. The parameters like Vibration Dose Value, SEAT factor and Ride Diagram values are used to evaluate the ride comfort. After successful evaluation of the vibration levels affecting the ride comfort of the driver as well as the passenger the next major task is to identify and study the cause of the discomfort. The cause of the discomfort is studied and analyzed in terms of the complex motion of the vehicle. Vehicle motions like choppiness produces higher levels of discomfort as compared to the vertical movement of the vehicle.

In order to specify the human dynamic comfort of seat vibration, a lot of work has been conducted in laboratory research. From the seating manufacturer's perspective, the author proposed a test method to measure the seat ride comfort by using a spring-mass dummy which was designed to match the human response in low frequency in vertical direction. A hydraulic table was employed as the excitation source to the occupied seat. Two seat samples, both measured with human occupants before, were used for this study. For simplicity and comparison, a sweep sine signal in vertical direction was used as the excitation signal. The transmissibility results measured of the dummy loaded seat were compared to those of human occupants. In this paper, a continuing effort focused on correlating the vibration response from dummy occupied seat to that from human occupied seat. A consistent relation was shown between the two measurements.

Accurate assessment of thermal comfort requires comprehensive analysis of the environmental effects contributing to the heat transfer to and from the human body. A common comfort evaluation approach (e.g. PMV/PPD, Equivalent Temperature) is to find a direct correlation of comfort to environmental conditions (e.g. air temperature, relative humidity, clothing), thus implicitly accounting for the relationship between physiological response and thermal comfort. An alternate approach (e.g. Berkeley Comfort Model, Fiala's DTS) is to explicitly correlate comfort to basic physiological response (e.g. skin and core temperature), thereby separating the thermal analysis portion of the problem from the more subjective comfort analysis portion. While it has been shown that comparable results can be obtained between environment-based comfort metrics and physiology-based comfort metrics, the latter should be employed for optimal prediction accuracy.

Camera sensors that are made of silicon photodiodes and used in ordinary digital cameras are sensitive to visible as well as Near-Infrared (NIR) wavelength. However, since the human vision is sensitive only in the visible region, a hot mirror/infrared blocking filter is used in cameras. Certain complimentary attributes of NIR data are, therefore, lost in this process of image acquisition. However, RGB and NIR images are captured entirely in two different spectra/wavelengths; thus they retain different information. Since NIR and RGB images compromise complimentary information, we believe that this can be exploited for extracting better features, localization of objects of interest and in multi-modal fusion. In this paper, an attempt is made to estimate the NIR image from a given optical image. Using a normal optical camera and based on the compressed sensing framework, the NIR data estimation is formulated as an image recovery problem.