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A numerical method for generating a blockloading profile from a rainflow histogram is described. Unlike previous techniques, this method produces a blockloading profile which, when rainflow-counted, yields a rainflow histogram identical to the original. When implemented with modern data acquisition and signal-processing techniques, this generation method provides a means of developing blockloading test profiles which are correlated with actual service data. This key benefit elevates existing simple testing systems as useful and productive tools despite the emrgence of more complex testing systems.

Product development processes generate large quantities of experimental and analytical data. The data evaluation process is usually quite lengthy since the data needs to be extracted from a large number of individual output files and arranged in suitable formats before they can be compared. When the data quantity grows extremely large, manual extraction cannot be done in a limited timeframe. This paper describes a set of tools developed by MTS engineers to automatically extract the desired information from a large number of files and perform data post-processing. The tools greatly improved both speed and accuracy of the evaluation process during the development of a sound quality-based end-of-line inspection system for seat tracks [1]. It allowed engineers to quickly gather a comprehensive understanding of the relative importance of individual design parameters and of their correlation to the subjective perception of the sound quality of the seat track.

Recently, the use of laboratory-based physical prototype testing as well as the design of virtual models and virtual test equipment has accelerated the pace and quality of racing vehicle development. In particular, the combined use of both virtual and physical testing, when correlated to racetrack improvements, yields a powerful development tool(1), (2),(3). In this study, we applied these techniques from the first stages of the design of a unique Grand Prix racing motorcycle. First, a wire-frame CAD model, then a parametric CAD solid model of the motorcycle was created after preliminary calculations specified the approximate design of structural elements. Subsequently, a virtual dynamic model was created and subjected to a variety of inputs, including sine sweeps, shaped white noise and simulated road time-histories. Loads and other dynamic responses were measured on the virtual model, so that it's design could then be optimized to yield acceptable performance and durability.

A precision compression molding press, the press controls, and mold temperature control are described. Controllability of the press motion, press force and the mold temperature have a significant impact on reduced cycle time, reduced material costs and reduced scrap in compression molding of “Class A” finish FRP structural panels. Conceptual ideas on automation of the process are presented that can substantially reduce labor costs and increase consistency of molded SMC panels.

Rapid development of advanced multi-axial load transducer systems now requires the use of computer-based analytical tools to assist the development engineer optimize the design to meet often-conflicting design targets. This paper presents a case study based on the development of a wheel force load transducer to meet a challenging set of performance goals including accuracy, repeatability, durability and insensitivity to the external environment. The paper also highlights the limitations of some of the current analytical tools when used for load transducer design, and how these limitations can be overcome by cost-effective combinations of analytical performance prediction and physical test confirmation.

It is an established fact that virtual knowledge based engineering has revolutionized R & D activities by streamlining processes, ensuring productivity and accuracy. This has resulted in freeing up time for quality interpretational work and decision making for engineering the best of products. Subsequently, homologation is a mandatory requisite activity for product signoff. It certifies the quality of the product and is an important factor in giving the product an authenticity for sale in the market. Homologation entails compliance to regulations existing in form of well-established standards which elaborate systematic and detailed guidelines on conducting physical testing for automotive systems, sub-systems or components for specific vehicle types.

Suspension development is one of the key steps in a complete vehicle development program. Computer simulation and analysis tools such as Multi Body Dynamics (MBD) simulation are used to refine initial concept and suspension parameters. Later on when a physical prototype is available the suspension system can be experimentally optimized at vehicle level. In this paper a new methodology is proposed which integrates virtual and experimental tools so that design, development and validation of the suspension system is carried out in the early phase of the vehicle development cycle with actual suspension components and without the need of a vehicle prototype. With this new approach, the design of any critical suspension components such as dampers can be optimized at the vehicle level. The new approach consists of combining the actual physical components on loading rig in closed loop with vehicle dynamic model running in real time.

In this work, the effect of tool rake angle and cutting speed on residual stresses of tool was studied, the rake angles of 0°, 5°, 10°, 15°, and 20° and a constant clearance (Relief angle) of 8° were used to turn bright mild steel on the lathe machine, A total of 15 experiments were carried out with three different cutting speeds (37.69, 59.37, 94.24 m/min) for each rake angle, keeping the feed rate and depth of cut constant. During the experimentation, the residual stresses were measured using an x-ray diffractiometer. This is all in order to explore the energy savings opportunities during regrinding of tools, useful production time and energy is being wasted due to regrinding or re-sharpening of tools when cutting tools got worn or blunt, selection of the rake angle which generate the optimum residual stresses in the tool, goes a long way in saving these time and energy.

The value of crash simulation has long been recognized by carmakers as an essential tool for vehicle development and certification programs. Driven by the need to minimize time-to-market for new models, cost reduction, and by consumer demand for safer cars and trucks, the industry is moving to newer technologies in crash simulation. Crash simulation provides an inexpensive means to quickly simulate the effects of a barrier crash by reproducing its basic elements - acceleration, velocity and displacement - in a nondestructive test. Crash event timing and accuracy of reproduction are critical performance factors. This paper describes the unique features and capabilities offered by a new generation of crash simulators.

A major manufacturer of small engines has recently implemented cold and hot start tests on the assembly lines of one of its engines. The cold start test refers to the test in which the engine is motored for a short time. Since this is a motored test, with no combustion occurring in the cylinder, the objective of this test is the detection of manufacturing and assembly defects. Next the engine undergoes a hot start test, in which fuel and air are supplied and the engine is started under a predefined load condition. This is a test performed to verify the performance of the engine under the application conditions. In both tests, typically multiple parameters are measured and extracted to assess the mechanical and thermal performance of the engine. Since noise level and sound quality of small engines have become major concerns for application manufacturers and end-users, an investigation was performed to assess the feasibility of including NVH parameters in the test criteria.