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Ongoing developments in crash safety research, regulations and product enhancements have indicated the need for a review on child dummy design philosophies. Late 1991, the TNO Crash-Safety Research Centre started a research program including a review on child anthropometry, a literature study on biomechanical properties of children and a study on scaling techniques. The objective of this research program is to establish sets of requirements for basic child dummy “design characteristics”. The main design characteristics covered in this paper are anthropometry and biofidelity. The anthropometry study resulted in a new TNO database on child anthropometry and includes published data on more than 75 parameters. The database's background and construction are explained and the main parameters for child dummy design are presented. The literature study on biomechanical properties of children revealed a limited set of data on material properties.

This paper details the development of the EX-80 composition, a new cordierite material for use as a diesel particulate filter (DPF), that was developed based on the following objectives; (1) improved thermal durability, (2) high filtration efficiency and (3) low pressure drop. The achievement of these goals was demonstrated through engine testing, stress modeling, and other evaluations. EX-80 has a low coefficient of thermal expansion (CTE) averaging less than 4x10-7°C-1 (25°C-800°C), the Modulus of Rupture (MOR) averages greater than 350 psi and the Modulus of Elasticity (MOE) averages less than 0.8 x 106 psi. The improvement of these three properties has resulted in improved thermal durability for EX-80 as compared to the current Corning DPF compositions (EX-47, EX-54 and EX-66). The new cordierite composition has been designed to achieve a low pressure drop as a function of soot loading (0.30 inHg/gm of soot collected), coupled with high efficiency, averaging greater than 90%.

The requirement of reducing HC emissions during cold start and improving transient performance has prompted a study of the fuel injection process. Port-fuel-injection with the Intake-valve open using small droplets is a potentially feasible option to achieve the goals. To gain a better understanding of the injection process, the effects of droplet size, injection timing, and coolant temperature on the total and speciated HC emissions were tested In a Single-cylinder engine. It was found that droplet size plays an important role in the total HC emission increase during open-valve injection, especially with cold operation. Large droplets (300 μm SMD) produced a substantial HC increase while small droplets (14 μm SMD) produced no observable increase. Increase In the total HC emissions was always accompanied by an increase in the heavy fuel components in the exhaust gases.

Since 1987, Van Doorne's Transmissie (VDT) BV has produced a steel belt for continuously variable transmission (CVT) applications. To date, over 750,000 vehicles have been equipped with the system, and belt reliability has proved to be very high. During the early stages of transmission production, an intermittent lubricant-related noise problem was encountered. This paper describes the steps taken to isolate the noise source and eliminate it. The noise, commonly called the “scratch phenomenon,” manifests itself as a transfer-gear rattle under slow-speed, light-load conditions. Initial investigation revealed that the scratch phenomenon could be avoided by using an alternative transmission fluid (1). Experimental work conducted by Lubrizol and VDT to understand the mechanism behind the problem: Established a relationship between the occurrence of the scratch phenomenon and the stick-slip properties of the belt-material/lubricant combination.

In this study, distributions of block compression force on the driving and driven pulleys were measured using a tiny load-cell inserted between two blocks and a telemeter system, under several constant speed ratios. Ring tension distributions were also measured using a specially devised block. From the experimental results, the following conclusions were drawn: (1) Block compression force distribution on the driving pulley is significantly different from that on the driven pulley. (2) Ring tension takes different value at each side of strings. It is considered that this phenomenon is caused by difference of saddle surface speed between two pulleys.

The trend towards increased individualism concerning the car's response to drivers' preferences is evident. In combination with the desire for high performance plus severe legal requirements on fuel consumption and emission levels this sets the powertrain engineer an almost impossible task. A Continuously Variable Transmission with full electronic control offers an opportunity to meet this challenge due to its infinite number of ratios within a wide ratio span. Based on the experience with 600000 CVT-cars in the field equipped with the VDT-belt a 250 Nm-CVT has been developed. This up-range CVT model features electronic controls for ratio and line pressure control, a torque convertor with lock-up and flow controlled pump. The transmission has been fitted to a 3, 3 I Chrysler Voyager.

Transmitted torque, thrusts of driving and driven pulleys, and axial force between two pulleys were measured on a metal pushing V-belt type CVT. Thrust ratios between driving and driven pulleys at several different speed ratios were plotted with respect to torque ratio and compared with each other. It was found that the relation between thrust ratio and speed ratio was almost independent of rotational speed of the pulley and the maximum transmittable torque at a constant torque ratio. The thrust ratio is primarily a function of speed ratio. It also depends on torque ratio and coefficient of friction between blocks and a pulley. An empirical equation for pulley thrust balance was derived. The equation is expressed in an explicit form. It is so simple that it can be applicable for electronic control of CVT.

Described in this paper is the design and development of an electronically controlled continuously variable transmission. The development was carried out by a Japanese and American partnership for use in vehicles with l000cc and 1300cc engines. The paper describes the technical features of the transmission and the development of the starting clutch, hydraulic control, electronic control, and the chain belt sheave system. The test results of vehicle performance and fuel economy are included.

After many years of joint development with Van Doorne's Transmissie BV, FORD has put a modern continuously variable transmission (CTX) for small FWD passenger cars in the market-place. Since May 1987 the CTX is offered in the 1.1 ltr. Fiesta as a low-volume pilot program. The very encouraging customer acceptance has strengthened FORD plans to launch high-volume production of the CTX for 1.1 ltr. Fiesta up to 1.6 ltr. Escort applications in foreseeable future. The CTX also forms the base for further CVT-developments, covering larger vehicles, bigger engines and electronic controls. The first part of this paper deals with initial field experience of the hydraulically controlled CTX in regard to driveability, comfort, performance and fuel economy. In the second part, improved control systems to fully utilize the potential of CVT's are described, including integrated powertrain management concepts.

A continuously variable chain transmission (cvt) used as main drive in motor-cars offers less fuel consumption, noise and toxic exhaust emission, combined with easy handling and comfortable driving. Design features, especially chain design and focal points of development are explained.

The Continuous Variable Transmission, though not new, may have attracted the reader's attention now several manufacturers have announced an automotive application. After 1.5 years experience in producing CV-Transmissions and the VDT-all metal CVT belt, VDT will give the reader a first insight in considerations that were made in the concept of the belt. A short overview of the actual way of applicating the belt in a transmission with respect to operating parameters is given in the last part of this contribution.

With the popularization of easy driving in Japan, the quest to improve the fuel economy and vehicle performance of a small car with a torque converter automatic transmission (AT) has led to the development of the Electro Continuously Variable Transmission (ECVT). The Subaru ECVT which combines an electronically controlled magnetic powder clutch with the van Doorne's steel belt drive system employs a couple of conventional synchromeshes as a means of forward/reverse change-over mechanism and simple hydraulic control valves. This combination has realized smoothness and quick response of CVT operation and provides a compact size for the CVT with the weight of 45.4 kg. Fuel economy of Subaru Justy ECVT car with the one liter engine is thus improved by 15 to 20 % in Japanese 10-mode test cycle and at the 60 km/H constant speed respectively in comparison with that of three speeds torque converter AT.

A transient three-dimensional model has been developed to simulate the thermal and conversion characteristics of nonadiabatic monolithic converters operating under flow maldistribution conditions. The model accounts for convective heat and mass transport, gas-solid heat and mass transfer, axial and radial heat conduction, chemical reactions and the attendant heat release, and heat loss to the surroundings. The model was used to analyze the transient response of an axisymmetric ceramic monolith system (catalyzed monolith, mat, and steel shell) during converter warm-up, sustained heavy load, and engine misfiring. The simulation indicates that high solid temperatures are encountered during sustained heavy load or engine misfiring, while steep temperature gradients are developed during the converter warm-up period. Flow maldistribution and radial heat loss are major sources for the thermal gradients.

Automotive thermal reactors have obtained high conversion efficiencies on engines with very rich carburetion, but fuel economy and reactor durability have suffered. Improved mixing of exhaust gas and secondary air in the engine exhaust port was examined as a means of improving reactor efficiency at less rich engine air-fuel ratios. Three air-injection systems which span a broad range of mixing capabilities were examined. Mixing characteristics were deduced from anemometry measurements of instantaneous secondary airflow, and emission performance of each system was generalized by a test program employing four steady-state conditions. High-pressure, timed air injection provides the best mixing and the best reactor performance. Sparger (radial discharge) air injection tubes provide fair mixing and better performance than conventional open-ended air injection tubes, which exhibit poor mixing characteristics.

This report presents the results of a three-year study designed to collect analyze, and reduce selected anthropometric data on 4027 infants and children representative of the current U.S. population ranging in age from newborn to 12 years of age. Since the major purpose was to provide basic measurement data most useful and critical to consumer product design, regulatory consideration, or other direct applications, 12 of the 41 measurements taken were applied measurements which have not been previously available. As an example of the direct application to product design, measurement of buttock depth on 3-to 6-month-old infants provided an objective basis for establishment of crib interslat distances. A substantial portion of the study involved the design, fabrication, development, and testing of a new generation of anthropometric measuring devices which transmit measurement signals to a portable mini-computer data acquisition system or to a set of readout meters.

A primary concern in the development of a passenger inflatable restraint system is the possibility that a child could be in the path of the deploying cushion either due to initial position at the time of an accident or due to precrash braking accompanying an accident. Previous studies by General Motors and Volvo have indicated that serious injuries to children are possible if the cushion/child interaction forces are not controlled by system design. This paper describes an instrumented child dummy which was developed to provide measurements of the various cushion/child interaction forces. An analysis is given describing the types of injuries which could be associated with the various types of interaction forces. These results were used to develop appropriate dummy instrumentation for indicating the severity of the cushion/child interaction. A description of the modifications made to an existing three-year-old child dummy are described.

The design and development of Mark II GT brake system within the parameters dictated by the Mark I chassis presented many problems. The Mark II GT with its larger 427 cubic inch engine had more weight and much higher performance than the Mark I. Space limitations of the carryover wheels and suspension imposed a severe handicap on individual brake component design. This was compounded by shortening the normal one year development time to a three month period. Part I of this paper is devoted to the consideration of factors which control the design of a brake. The concept of kinetic energy and its effects on brake performance is reviewed briefly. Use of the ventilated rotor design is explained for applications where severe heat is a problem, as in the case of the Mark II GT. The development of the brake system from the 24 hour Daytona endurance race to the Le Mans Grand Prix race is reviewed.