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Technical Paper

"Quattro"-Drive for Every Day Driving

1984-01-01
845070
An essential feature of the Audi Quattro permanent four-wheel drive system is in the inter-axle differential located on the hollow output shaft in the gearbox: the drive is taken from this differential forward to the front differential through the inside of the hollow shaft, and rearward to a propellor shaft driving the rear differential. The major advantages in everyday driving include improved traction and a reduced tendency toward throttle induced changes of attitude. The greater traction allows not only better progress in difficult road conditions; it also gives better acceleration in difficult traffic situations, such as when joining a busy main road. The more easily predictable handling response to throttle changes means that Quattro vehicles have better tracking stability. Altogether, the active safety and "roadability" are considerably improved.
Technical Paper

1958 Chevrolet LEVEL AIR SUSPENSION

1958-01-01
580049
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.
Technical Paper

2-Way Driven Compressor for Hybrid Vehicle Climate Control System

2004-03-08
2004-01-0906
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.
Technical Paper

20 A Combined Experimental and Numerical Approach for Motorcycle Crank Noise: Experimental Validation

2002-10-29
2002-32-1789
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.
Journal Article

26,500km Down the Pan-American Highway in an Electric Vehicle A Battery's Perspective

2012-04-16
2012-01-0123
This paper presents a novel battery degradation model based on empirical data from the Racing Green Endurance project. Using the rainflow-counting algorithm, battery charge and discharge data from an electric vehicle has been studied in order to establish more reliable and more accurate predictions for capacity and power fade of automotive traction batteries than those currently available. It is shown that for the particular lithium-iron phosphate (LiFePO₄) batteries, capacity fade is 5.8% after 87 cycles. After 3,000 cycles it is estimated to be 32%. Both capacity and power fade strongly depend on cumulative energy throughput, maximum C-rate as well as temperature.
Technical Paper

3D Head Models for Protective Helmet Development

2003-06-17
2003-01-2176
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.
Technical Paper

4-Wheel-Drive Tractors From John Deere “Concepts 1982”

1981-09-01
810913
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.
Technical Paper

42 V Electric Air Conditioning Systems (E-A/CS) for Low Emissions, Architecture, Comfort and Safety of Next Generation Vehicles

2001-08-20
2001-01-2500
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.
Technical Paper

520 Bobcat Designed for Improved Serviceability

1976-02-01
760404
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.
Technical Paper

6 Speed Transverse Manual Gearbox for High Torque Application

2016-04-05
2016-01-1095
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.
Technical Paper

64 Ergonomic Approaches to Improved Scooter Riding Comfort

2002-10-29
2002-32-1833
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.
Technical Paper

A 2D Model for Tractor Tire-Soil Interaction: Evaluation of the Maximum Traction Force and Comparison with Experimental Results

2011-04-12
2011-01-0191
The paper investigates the interaction between soil and tractor tires through a 2D numerical model. The tire is schematized as a rigid ring presenting a series of rigid tread bars on the external circumference. The outer profile of the tire is divided into a series of elements, each one able to exchange a normal and a tangential contact force with the ground. A 2D soil model was developed to compute the forces at the ground-tire interface: the normal force is determined on the basis of the compression of the soil generated by the sinking of the tire. The soil is modeled through a layer of springs characterized by two different stiffness for the loading (lower stiffness) and unloading (higher stiffness) condition. This scheme allows to introduce a memory effect on the soil which results stiffer and keeps a residual sinking after the passage of the tire. The normal contact force determines the maximum value of tangential force provided before the soil fails.
Technical Paper

A Case Study on the Development of the Automobile Body Industries in Indonesia

1983-11-07
830874
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.
Technical Paper

A Comfort Field Study in Public Transportation Buses

1999-03-01
1999-01-0894
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.
Technical Paper

A Communication System for Driver Aid, Information, and Routing

1967-02-01
670111
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.
Technical Paper

A Comparative Analysis of Radial and Bias R-1 Drive Wheel Tractor Tires

1975-02-01
751185
Since the pneumatic farm tire was developed, the basic carcass construction has been bias or diagonal plies. As tractor manufacturers continue to produce models with higher and higher horsepower, it has become evident that the conventional design changes--lug shape, lug angle, aspect ratio, etc.--are no longer sufficient to achieve significant improvements in tractor drive wheel tire performance. After investigating various alternatives, B.F.Goodrich determined that a radial construction offered distinct performance advantages over a bias construction without requiring any redesigning of the tractor. These include: increased traction, reduced fuel consumption, longer wear and improved ride. This paper will present comparative performance results of radial and bias drive wheel tractor tires, and discuss the basic radial tire mechanics which make the performance improvements possible.
Technical Paper

A Comparative Study to Assess the Effect and Cause of Ride Quality and Comfort of Passenger Vehicle with Subjective Correlation

2019-11-21
2019-28-2410
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.
Technical Paper

A Comparison Test of Transmissibility Response from Human Occupant and Anthropodynamic Dummy

1998-02-23
980655
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.
Technical Paper

A Comparison of Physiology-Based Metrics to Environment-Based Metrics for Evaluating Thermal Comfort

2013-04-08
2013-01-0844
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.
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