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Moir� method is useful to measure the shape and the whole-field distributions of displacement and strain of structures. There are many kinds of moir� methods such as geometric moir� method, sampling moir� method, Fourier transform moir� method, moir� interferometry, shadow moir� method and moir� topography. Grating method analyzing directly deformation of a grating without any moir� fringe pattern is considered as an extended technique of moire method. Phase analysis of the moire fringe patterns and the grating patterns provides accurate measurements of shapes or displacement and strain distributions. Some applications of these moir� methods and grating methods to dynamic shape and strain distribution measurements of a rotating tire, sub-millimeter displacement measurements from long distance for landslide prediction, real-time shape measurements with micro-meter order accuracy, etc. are shown. Presenter Yoshiharu Morimoto, Moire Institute Inc.

Virtual testing is a method that simulates lab testing using multi-body dynamic analysis software. The main advantages of this approach include that the design can be evaluated before a prototype is available and virtual testing results can be easily validated by subsequent physical testing. The disadvantage is that accurate specimen models are sometimes hard to obtain since nonlinear components such as tires, bushings, dampers, and engine mounts are hard to model. Therefore, virtual testing accuracy varies significantly. The typical virtual rigs include tire and spindle coupled test rigs for full vehicle tests and multi-axis shaker tables for component tests. Hybrid simulation combines physical and virtual components, inputs and constraints to create a composite simulation system. Hybrid simulation enables the hard to model components to be tested in the lab.

Two-poster rig plays a very important role in accelerated durability evaluation in a motorcycle industry, similar to what a four-poster rig does in a car industry. The rig simulates the exact road conditions in the vertical direction through tire coupling by applying feedback control on displacement. On account of its ability to simulate to the exact customer usage conditions, it reproduces the failures realistically as it happens on the field. However, as complete vehicle is required for testing on the rig, the testing happens mostly in the advanced stages of product development. Any failures beyond the concept stage have a huge impact on the development time and cost and the same should be avoided. Therefore, in this paper, a virtual testing methodology is proposed, based on which potential failures on the vehicles can be captured at the concept design stage itself. An ADAMS model of a motorcycle was created.

Hybrid vehicle simulation methods combine physical test articles (vehicles, suspensions, etc.) with complementary virtual vehicle components and virtual road and driver inputs to simulate the actual vehicle operating environment. Using appropriate components, hybrid simulation offers the possibility to develop more accurate physical tests earlier, and at lower cost, than possible with conventional test methods. MTS Systems has developed Hybrid System Response Convergence (HSRC), a hybrid simulation method that can utilize existing durability test systems and detailed non-real-time virtual component models to create an accurate full-vehicle simulation test without requiring road load data acquisition. MTS Systems and Audi AG have recently completed a joint evaluation project for the HSRC hybrid simulation method using an MTS 329 road simulator at the Audi facility in Ingolstadt, Germany.

To meet the latest trends in Internal Combustion engines regarding efficiency, emissions and durability, an integrated approach to engine development is required. This paper describes about a Robust, Reliable and an integrated approach used in design and development of an engine for high power density which can be adopted for both Off-highway application as well as Genset application. The engine is developed to meet US - EPA Tier-III Emission Norms and MoEF (Genset Emission Norms for India formulated by Ministry of Environment and Forest) emission norms respectively. This paper discusses various technologies applied in developing this engine to achieve high power density, low exhaust emissions, and low noise and vibrations. This 4 valve per cylinder engine is created largely within a digital environment using the latest computer aided design (CAD) and computer aided engineering (CAE) techniques and simulation tools.

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.

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.

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.

ADAMS, SIMULINK, and ADAMS-SIMULINK co-simulation models of component test systems, Multi-Axis-Simulation-Table (MAST) systems, and spindle-coupled vehicle testing system (MTS 329) were created. In the ADAMS models, the mechanical parts, joints, and bushings were modeled. Hydraulic and control elements were absent. The SIMULINK models modeled control and hydraulic elements including actuator dynamics, servo valve dynamics, closed loop control, three-variable control, matrix control, and coordinate transformation. However, the specimen had to be simplified due to the limitation of SIMULINK software. The ADAMS-SIMULINK co-simulation models considered hydraulic and control components in the SIMULINK portion and mechanical components in ADAMS portion. The interaction between the ADAMS and SIMULINK portions was achieved using ADAMS/Control.

Environmental pollution is of great concern; hence the emission norms for the diesel engines are made more stringent. The purpose of this work is to develop a process to optimize the FIS parameters and select a most suitable FIS by simulation to meet the target emissions. During the combustion optimization exercise of diesel engine, different hardware combinations like injector, HPP etc are matched through testing to achieve the required performance and emissions. The process requires the real testing of the engine on engine dynamometer with various hardware combinations, which is expensive and time consuming. A simulation model of diesel FIS is constructed using ‘AVL Hydsim’. The model is validated by comparing the predicted and the experimental results. The validated model is used for further work. Critical parameters were listed based on the sensitivity analysis on the base model.

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.

Anthropometric data of a country is vital database for automotive design and other design applications. It is also an important parameter in population studies. Most developed countries have invested resources over the years to develop such a database and this information is accessed by many OEMs and major Design Houses. However, an updated and comprehensive Anthropometry of Indian Population is largely unknown. In the past, a few institutions have done projects to bring out a picture of the Indian Anthropometry. However, keeping in view the rapid industrialization and increase of India-specific designs which require an access to latest Anthropometric database, the project “SIZE INDIA” has been initiated. For the first time in India, a state of the art 3D Whole body scanner technology has been used and thereby large volume of data has been generated in a very short span of time.

Exhaust noise is the major noise source for the automotive vehicle contributing to its interior as well as exterior noise. The Transmission Loss (TL), noise reduction, Insertion Loss (IL) and radiated noise are the major characteristics used to describe the performance of a muffler in an automotive exhaust system. Out of these characteristics, Insertion loss and exhaust radiated sound pressure levels plays a significant role in muffler design as it is a measure of true performance of muffler along with engine/vehicle and very much useful for the designers to compare different silencer configurations. In present work, the sound source is modelled by acoustic impedance and volume velocity of the engine. Since it is difficult to estimate the sound source impedance of the exhaust by measurements either with direct or indirect methods as both are prone to errors and difficult to implement, the empirical equations are used to define exhaust source, to have reasonable accuracy.

Seat system resonant frequencies play an important role in seat design and ride dynamics. So NVH performance of the seats should be assessed from the viewpoint of tactile, acoustic and visual sense. Tactile response is the response of sub-systems, which is induced when the human body contacts steering wheel, footrest or seats. Acoustic response is the behavior of the seat system at the cavity resonance frequencies and visual sense is what we perceive under actual operating conditions. The objective of the present work is to conduct and correlate experimental modal test with FE modal test to identify tactile vibrations. Then the identified main seat modes will be used to set the mode map (seat target) at the stage of full vehicle level. This work will present a practical approach in understanding varied methods and techniques for determining resonant characteristics and for subsequent refinement of FE model.

The Partially Pre-mixed Charge Compression Ignition (PCCI) combustion was experimentally and computationally investigated with retarded injection timing for mixture homogeneity and for lower emissions. PCCI combustion concept was experimentally evaluated with retarded injection timing close to TDC with high EGR levels up to 50%. The CFD analysis has carried out for mixture homogeneity with different injection pressures and timings. A 4-cylinder TCIC engine having 2valves/cylinder were selected for experiments and speed vs. torque mapped for LCV applications. A Visio technique has been used to study the in-cylinder combustion. After fine tuning of injection pressure, injection timing and EGR ratio over entire range of engine speeds and loads, a 13-mode ESC test cycle has been carried out for EURO-IV and EURO-V emissions. Experimental results shows that it is possible to meet EURO-IV emissions with combined PCCI-DI combustion concept with economical aftertreatment solution.

The acoustical performance of a vehicle dash panel system is rated by the noise reduction, which is calculated from the sound transmission and absorption characteristics. A typical dash insulator consists of a steel panel (vehicle body panel), a porous decoupler and heavy layer in the form of sandwich construction. The use of dash panel is to block engine noise from entering into the interior cabin. In the present study the transmission loss of dash panel has been evaluated in reverberation chambers and the sound absorption of dash panel has been determined in impedance tube. This paper deals with improving over all sound transmission loss and shifting of the double wall resonance well below the engine firing frequencies by changing the decoupler materials such as felt and foams of different density and thickness and heavy layer mass per unit area.

Recent trends towards design of High Performance Diesel engines creating more challenges in the area of design, durability and NVH aspects of components and systems. In particular, Valvetrain system of High Speed application engines is one of the most critical and complicated dynamic system in terms of precise control of events, max. Lift, control over accelerations and vibration related issues. This can be tackled by designing the cam profile for better valve train dynamics. High frequency components and/or excessive jerks in a cam profile are important sources of cam-follower vibrations. There are various techniques of designing cam profile to achieve controlled valve train dynamic behavior at high speed operations. Present paper discuss the impact of various cam profile options designed using Polydyne, N-Harmonic and B-Spline methodologies on a field problem of cam wear for high speed engine application.

Heat release analysis brings out the various phenomena that cause the development of the combustion chamber pressure. A three-zone heat release model computes the rate of heat release and other properties of all the three zones (representing vaporized fuel, unburnt and burnt gas zones) from measured pressure-crank angle data obtained from an instrumented engine. It is a useful diagnostic tool giving a great deal of information about an existing engine. Heat release analyses for five different operating conditions have been conducted for a DI diesel engine. Also, ignition delay, wall heat losses and mass, volume and temperature in each of the three zones have been computed. It is found that the overall quality of the computed heat release rates are strongly dependent on the accuracy of the measured pressure data. The model can be integrated to a high speed data acquisition system for concurrent analysis of the heat release patterns.

Engine maps consisting of three-dimensional contour plots of engine performance parameters such as bsfc in the engine speed - bmep plane give a large amount of information in a very concise manner. Such maps can be drawn for many more parameters of interest if a high speed data acquisition system, such as E-DACS (Engine Data Acquisition and Control System) which was developed in-house, is used to obtain the transient data of combustion chamber pressure. New maps of: pmax, (dp/dθ)max, etc. from the pressure-crank angle data; isfc, imep, pumping losses, etc. from the pressure-volume data; ignition delay, burn angle, maximum rate of burning, maximum burnt gas temperature, etc. after conducting heat release analysis using the pressure-crank angle data, can be generated. Such an enlarged view offered by these new sets of engine maps will definitely prove useful to engineers, giving them newer insights.

The characteristics, functionality, limitations, and applications of mid-level driving simulators are reviewed and discussed. For this paper a mid-level simulator is defined as one which has a large roadway scene display typically comprising animated computer graphics, it may have a motion system or be fixed base, it should have a dedicated cab with a steering feel system and interactive controls and displays, it has a parametrically configurable vehicle dynamics model, data acquisition is provided for, and the simulator is intended to be used for driver behavior research and vehicle or highway research and development studies. Possible simulator sickness issues are discussed, and categories of mid-level driving simulator applications are noted. Approximately 20 different contemporary driving simulators are included in the survey.