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Technical Paper

32 Development of Silent Chain Drive System for Motorcycles

Examining the noise reduction of a motorcycle, the requirement of an effective method of reducing a drive chain noise has been a pending issue similarly to noise originating from an engine or exhaust system, etc. Through this study, it became clear that the mechanism of chain noise could be classified into two; low frequency noise originated from cordal action according to the degree of chain engagement and high frequency noise generated by impact when a chain roller hits sprocket bottom. An improvement of urethane resin damper shape, mounted on a drive side sprocket, was effective for noise reduction of the former while our development of a chain drive that combined an additional urethane resin roller with an iron roller worked well for the latter. The new chain system that combined this new idea has been proven to be capable of reducing the chain noise to half compared with a conventional system.
Technical Paper

60 TCT - Total Combustion Technology

TCT - Total Combustion Technology is technology designed to enable small SI four-stroke and two-stroke engines to meet current and proposed emission standards that pertain to small engines. This paper outlines the technology, the testing equipment, and the results from tests comparing TCT to original carburetors on two different engines. The comparison shows clearly that emissions can be reduced substantially by TCT. The MLC (Mechanical Lambda Control) feature of TCT allows the emission profile of the engine to be matched to the application in each case.
Technical Paper

A Bridging Technology to Combine Test and Simulation with In-Situ TPA

To shorten development processes and to secure decisive product properties as early as possible, new methods for product development are required. These must provide the capability to generate the maximum information about the future product out of available data at the respective development step. Computer-aided engineering (CAE) is therefore becoming increasingly important. It allows prediction of product properties at an early development stage and partial replacement of physical prototypes with numerical models (virtual prototypes). However, the transition from experiment-based methods to numerical approaches is a big and potentially unreliable step. Often, purely-numerical examinations are only applicable to a limited extent because of the following reasons: complex modeling, missing data or input data with major uncertainties, lack of expertise, or development processes not suitable for numerical methods.
Technical Paper

A Comparative Analysis of the Thermal Efficiency of 1977 and 1978 Model Year Vehicles Under Chassis Dynamometer Conditions

Comparison of vehicle thermal efficiency and engine load factor for 1977 and 1978 model year certification vehicles shows low correlation. At any load factor, the spread in thermal efficiencies was on the order of 2 to 1. These facts suggest that, with existing technologies, vehicle manufacturers can realize a significant improvement in fuel economy through better matching of engines (specific fuel consumption), transmissions and final drive ratios to vehicle power requirements.
Technical Paper

A Comparative Study on Energy Management Strategies for an Automotive Range-Extender Electric Powertrain

In this work, the influences of various real-timely available energy management strategies on vehicle fuel consumption (VFC) and energy flow of a range-extender electric vehicle were studied The strategies include single-point, multi-point, speed-following, and equivalent consumption minimization strategy. In addition, the dynamic programming method which cannot be used in real time, but can provide the optimal solution for a known drive situation was used for comparison. VFCs and energy flow characteristics with different strategies under Worldwide Harmonized Light Vehicles Test Cycle (WLTC) were obtained through computer modeling, and the results were verified experimentally on a range-extender test bench. The experimental results are consistent with the modeled ones in general with a maximum deviation of 4.11%, which verifies the accuracy of the simulation models.
Technical Paper

A Comparison of Direct Vehicle Fuel Consumption Measurements with Simultaneous CVS Carbon-Balance Fuel Economy

A chassis dynamometer test cell is employed along with a CVS system to test for both vehicle mass emissions and for fuel economy. In addition to the standard test equipment for gasoline vehicles, a highly accurate fuel flow meter is installed that measures the mass of fuel consumed by the engine during chassis dynamometer tests. A 3.8 liter V6 vehicle was tested over standard United States E.P.A. FTP and Highway Fuel Economy protocols, where it is found that the fuel flow meter mass measurements correlate with the carbon-balance fuel consumption results measured with the CVS. However, there are significant differences between the fuel flow meter and the CVS measured fuel consumption during vehicle cold-start tests. This is a concern because a large fraction of gasoline engine emissions are generated only during a cold-start. It is important to be able to relate mass emissions to mass fuel consumption in order to understand and control cold-start gasoline engine performance.
Technical Paper

A Comparison of World Braking Standards with Reference to the Development of Japanese Braking Standards

A new Committee on Japanese Automobile Standards for Brakes has been established to issue standards covering road tests, dynamometer tests, nomenclature, etc. This paper discusses several of these. The Committee also reviewed the regulations and standards of various countries for comparison purposes. In order to have rational standards, ample data on vehicle usage, analysis of brake characteristics, and study of basic human engineering will be needed. Correlation among road tests, dynamometer tests, and test equipment must be established. Amalgamation of various national standards into a single international standard is desirable goal.
Technical Paper

A Comparison of the Coastdown and Steady State Torque Methods of Estimating Vehicle Drag Forces

Accurate measurement of a vehicle's resistance to straight line motion on a road (road load), and the separation of this resistive force into its contributory components is of fundamental importance for the calibration of a modern chassis dynamometer and to provide the data required for vehicle performance assessment. The coastdown and steady-state torque tests are the established means of determining the road load on a test track. Differences in vehicle operating conditions and the instrumentation used during the tests lead to variations in the values obtained for the coefficients in the road load equation. This paper describes an investigation into these test methods to determine their relative accuracies, and to compare the results obtained in the different modes. On vehicle anemometry is used to improve the overall accuracy achieved in both types of test.
Technical Paper

A Correction Factor Investigation of a Turbocharged Diesel Engine

The increased use of turbocharged diesel engines for automotive applications has accentuated the need for accurate power correction functions. The study's purpose was to evaluate the effect of dry ambient intake air pressure, ambient intake air temperature, engine speed, and humidity upon the performance of a turbocharged diesel engine. Each effect is examined individually and weighted in a final relationship for standardized horsepower. Power correction formulas, in a form readily comparable to typical correction functions, are derived from the results. Testing was conducted through the use of various special test procedures, calibrations, and test equipment. With computer aid, test evaluation was conducted by utilizing various analytical and graphical methods. An accuracy comparison between actual and calculated values of power correction is presented.

A Guideline for Aerospace Platform Fiber Optic Training and Awareness Education

This document establishes training guidelines applicable to fiber optic safety training, technical training and fiber awareness for individuals involved in the manufacturing, installation, support, integration and testing of fiber optic systems. Applicable personnel include: Managers Engineers Technicians Logisticians Trainers/Instructors Third Party Maintenance Agencies Quality Assurance Shipping Receiving Production Purchasing

A Guideline for Aerospace Platform Fiber Optic Training and Awareness Education Aerospace Fiber Optics Engineer Knowledge Competencies

This document establishes training guidelines applicable to fiber optics engineer technical training for individuals involved in the manufacturing, installation, support, integration and testing of fiber optic systems. Applicable personnel include: Managers Engineers Trainers/Instructors Third Party Maintenance Agencies Production

A Guideline for Aerospace Platform Fiber Optic Training and Awareness Education Introduction to Aerospace Fiber Optics Knowledge Competencies

This document establishes training guidelines applicable to fiber optic safety training, technical training and fiber awareness for individuals involved in the manufacturing, installation, support, integration and testing of fiber optic systems. Applicable personnel include: Managers Engineers Technicians Logisticians Trainers/Instructors Third Party Maintenance Agencies Quality Assurance Shipping Receiving Production Purchasing
Technical Paper

A Laboratory Fatigue Test Program for Steering Components Based on Field Load Data

More meaningful laboratory testing can be achieved from test programs designed to better simulate the usage of the component or system in the hands of the consumer. Steering gears and linkages are adaptable to force measurement during vehicle operation. This data can then be used to program laboratory test equipment in a manner which simulates the force environment encountered in vehicle usage.
Technical Paper

A Low Temperature Coolant Conditioning Cart for Testing DEF Thawing Systems

Diesel Exhaust Fluid (DEF) systems are required to function in cold ambient temperatures below the freezing point of DEF. Manufacturers may demonstrate compliance by following an EPA guidance procedure described below [2], using whole vehicles at winter test sites at −18 deg C or lower. However, commercial trucks may have multiple variants with different DEF system layouts, so it is impractical to test every possible configuration. A climatic chassis dynamometer (CCD) can also be used for this test, but this is still expensive and time consuming, and does not address the problem of complexity. Instead, much time and expense can be saved by using simulation methods to identify worst case configurations, and to demonstrate with confidence that a limited number of tests will cover the whole possible range. This methodology can further be used to show that a range of vehicles can be represented with selected rig tests in a cold chamber.
Technical Paper


A test procedure for deriving a radiated emissions transfer function has been developed. The function shows an empirical relationship between the harmonic content of signals on a balanced transmission line and corresponding electric field intensities at a given distance from the line. Test results indicate good correlation with this procedure below 50 megahertz. The transfer function may be used in conjunction with predetermined emission limits to provide the designer with a method of defining signal characteristics for complying with those limits. A description of the test procedure and its range of application is discussed, focusing on a method of performing the test in a high ambient signal environment using automated test equipment.
Technical Paper

A Manufacturer's Approach To “U” Seal Development

This paper outlines a seal manufacturer's development of a single lip seal for reciprocating hydraulic cylinders. It traces the development of functional test equipment and a uniform method for evaluating the performance of seals.
Technical Paper

A Method for Rapid Durability Test Development

Designing a durability test for an automatic transmission that appropriately reflects customer usage during the lifetime of the vehicle is a formidable task; while the transmission and its components must survive severe usage, overdesigning components leads to unnecessary weight, increased fuel consumption and increased emissions. Damage to transmission components is a function of many parameters including customer driving habits and vehicle and transmission characteristics such as weight, powertrain calibration, and gear ratios. Additionally, in some cases durability tests are required to verify only a subset of the total parameter space, for example, verifying only component modifications. Lastly, the ideal durability test is designed to impose the worst case loading conditions for the maximum number of internal components, be as short as practicable to reduce testing time, with minimal variability between tests in order to optimize test equipment and personnel resources.
Technical Paper

A Method for the Instantaneous Torque Measurement of Braking or Motoring Machines Under Steady or Transient Operation Using Digital Techniques

This work will present a digital system that allows an on-line experimental determination of the instantaneous torque of either motoring or braking machines. With the procedure developed the machine under test accelerates or decelerates a rigid inertia and all that is required to obtain the instantaneous torque is the instantaneous angular speed signal. An additional external braking or motoring machine, like a dynamometer, is not strictly required, but can add certain value to the testing capabilities. The amount of the total inertia under motion can be determined as part of the actual process with this method. Digital time invariant linear filters are used to process the speed signal using a conventional high level language code running in a microcomputer. The non recursive filters were designed to obtain a short convolution time with a small memory penalty and to handle a noisy speed signal.
Technical Paper

A Method to Measure Air Conditioning Refrigerant Contributions to Vehicle Evaporative Emissions (SHED Test)

Although the intent of the SHED test (Sealed Housing for Evaporative Determination) is to measure evaporative fuel losses, the SHED sampling methodology in fact measures hydrocarbons from all vehicle and test equipment sources. Leakage of air conditioning (AC) refrigerant is one possible non-fuel source contributing to the SHED hydrocarbon measurement. This report describes a quick and relatively simple method to identify the contribution of AC refrigerant to the SHED analyzer reading. R134A (CH2FCF3), the hydrofluorocarbon refrigerant used in all current automotive AC systems, as well as its predecessor, the chlorofluorocarbon R12, can be detected using the gas chromatography methods currently in place at many emissions labs for the speciation of exhaust and evaporative hydrocarbon emissions.