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This paper will identify the role of the engineer in the Total Quality Management movement. In the latter 1980's quality and reliability were identified as being a result of good business practices, rather than only being effected by manufacturing and design systems. In the past, engineers were given total design responsibility with little or no control once the design left their hands. Product cost analysis recently identified approximately 65% of product cost comes from areas which the engineer cannot control. This paper will show how the skills of the engineer are being integrated into the total business environment through a structured planning system, resulting in products and services with customer focus. Quality and reliability in the 1990's will be a result of this well defined and applied business system.

An expansion tank is an integral part of an automotive engine cooling system. The primary function of the expansion tank is to allow the thermal expansion of the coolant. The expansion tank will be referred as hot bottle in this paper. In the System level modeling of the engine internal flow, it is imperative to accurately model and characterize the components in the system. It is often challenging to define the hot bottle accurately with limited parameters in the 1D modeling. Currently it is very difficult to optimize the system by testing. Since testing consumes a lot of time and changes in development stage. If the hot bottle component is not defined properly in the system network, then the system flow balancing cannot be predicted accurately. In this paper, the approach of creating a 1D modeling tool for hot bottle flow prediction is discussed and the simulation results are compared with the physical test data.

The potential contributions of acoustical technology to manufacturing companies pervade nearly all of its functions from marketing and product planning to design engineering and quality control. Despite this, however, companies generally feel uneasy when they embark on programs to use acoustics in their operations because the technology seems complicated and somehow harder to “get a handle on” than it is in other cases. But the issues of product sound, and the benefits of acoustics on a diagnostic tool are too important to ignore, so in this paper we discuss these issues in a “20 questions” format to help planners, engineers and managers as they proceed to implement acoustical technology in their organizations.

Challenges surrounding OEM′s go far beyond to manufacture and delivery high quality vehicles. A perfect design and performance in the lowest cost possible is extremely essential to delivery to the customer the best vehicles. In order to guarantee all these targets, a robust process must be set to developed and implemented. It is known all process limitations, which faces the emergent markets and the lack of infrastructure considering the developed countries. All this limitations can deeply affect the robustness of the process. Some innovative solutions are becoming common from the engineering development combined with the manufacturing team to work out these limitations and provide excellent process stability. In this present paper it will be discussed the Bi component structural adhesive (2K PU epoxy) utilization to establish the process in the assembly line, mainly in order to improve parts dimensionally.

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.

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.

Hydrodynamic parameters play a major role in the dynamics and control of Autonomous Underwater Vehicles (AUV). The performance of an AUV is dependent on the parameter variations and a proper understanding of these parametric influences is essential for the design, modelling and control of high performance AUVs. In this paper, a six sigma framework for the sensitivity analysis of a flatfish type AUV is presented. Robust design techniques such as Taguchi’s design method and statistical analysis tools such as Pareto-ANOVA, and ANOVA are used to identify the hydrodynamic parameters influencing the dynamic performance of an AUV. In the initial study, it is found that when the vehicle commanded in forward direction, it is in bow down configuration which is unacceptable for AUV motion. This is because of the vehicle buoyancy and shape of the vehicle. So the sensitivity analysis of pitch angle variation is studied by using robust design techniques.

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.

Newer automobiles have complex dynamic and stability controls due to regulations, competition, and safety concerns. More systems require testing at the subcomponent level to ensure proper operation in the final vehicle assembly. Many of the stability and navigation features originally designed for aircraft components are now being incorporated into automobiles. Certain types of motion test simulators were originally designed for testing aircraft sensors as: gyroscopes, inertial navigation systems (INS), inertial measurement units (IMU), and attitude heading and reference systems (AHARS) This same type of equipment is now used for automotive testing as: airbag fuse sensors, anti-skid sensors, rollover sensors, vehicle stabilization systems, active suspension sensors, and navigation systems.

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.

Non-Asbestos Organic (NAO) disc pads and Low Steel Lomet disc pads were subjected to high and low humidity conditions to discover how humidity affects these two classes of formulations for physical properties, friction, wear and noise characteristics. The 2 classes of formulations show similarities and differences in response to increasing humidity. The humidity effect on deformation of the surface microstructure of the gray cast iron disc is also investigated. Humidity implications for pad quality control and brake testing are discussed.

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.

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.

Precise prediction of combustion parameters such as peak firing pressure (PFP) or crank angle of 50% burned mass fraction (MFB50) is essential for optimal engine control. These quantities are commonly determined from in-cylinder pressure sensor signals and are crucial to reach high efficiencies and low emissions. Highly accurate in-cylinder pressure sensors are only applied to test rig engines due to their high cost, limited durability and special installation conditions. Therefore, alternative approaches which employ virtual sensing based on signals from non-intrusive sensors retrieved from common knock sensors are of great interest. This paper presents a comprehensive comparison of selected approaches from literature, as well as adjusted or further developed methods to determine engine combustion parameters based on knock sensor signals. All methods are evaluated on three different engines and two different sensor positions.

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.

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.

Passenger car NAO(Non-Asbestos Organic) disc pads were subjected to low and high humidity conditions. Humidity is found to measurably affect pad dimensions, pad hardness, compressibility, friction, pad wear, disc wear, disc roughness, DTV(Disc Thickness Variation) and brake noise. Also the friction film is found to absorb a significant amount of moisture. It is essential to have a tight control of temperature and humidity for brake testing and quality control if meaningful data are to be generated with minimum variability. Seasonal changes must be considered for brake testing on the road.

The results of torque measurements as well as discussion of different parameters which affect the measured value of torque are presented. The influence of methodology of experiments carried-out in either high or low temperatures has been accentuated.

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.