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Wheel force and moment transducers (WFT) are widely used in vehicle testing and analysis [1], [2], [3]. There are many benefits of using these sensors. To install the transducer, vehicle wheel has to be modified. Transducer mounting adaptors are required to interface the sensor with the modified wheel rim. To study the effect of added mass with wheel force transducers, three vehicles, two types of passenger cars, and one SUV, were instrumented with an MTS spindle wheel force transducer (SWIFT 30A) as well as with regular wheels. The instrumented vehicles were driven on multiple proving ground surfaces with three passes for each vehicle. This experimental data was analyzed using RPC Pro software to assess both per pass variation and data trends from 3 passes without WFT (baseline) and 3 passes with WFT added mass. A validated ADAMS model of a production passenger vehicle, with and without added weight of the wheel force transducers, was also used to assess the added weight effect.

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.

In a developing country like India, Two-wheelers dominate the automotive market with around 80% market shares. In Indian city traffic conditions, driving a two wheeler is a tiresome job. Manual transmission makes this task even further uncomfortable. So an automatic transmission is a better solution. A new automatic transmission system is developed which can reduce fatigue of drivers. Steps of ARIZ (Algorithm for Inventive Problem Solving) were followed. Ideas or concepts for the design were proposed from various fields and were compared for various parameters like size, weight, complexity, manufacturability, feasibility, efficiency and cost. They were also compared with the existing transmission systems. Based upon the results of the comparison, 5 designs were selected and they were analyzed thoroughly. Finally one design was selected.

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.

Diesel engines dominate in Heavy-Duty applications due to its better fuel economy, higher durability and larger reliability. Fuels derived from petroleum resources are depleting daily and it’s become a scarce resource for future generation to come. With growing environmental consciousness of the adverse implications brought by excessive usage of fossil fuels, the battle for finding alternative fuels as their substitution is getting heated up. At present, renewable energy from bio-fuels has been peddled as one of the most promising substitution for petroleum derived diesel. Using bio-ethanol blended diesel fuel for automobile can significantly reduce diesel usage and exhaust greenhouse gases. Bio-ethanol can be produced by alcoholic fermentation of sucrose or simple sugars. The main drawback is that ethanol is immiscible with diesel fuel over a wide range of temperatures, and the hygroscopic nature of ethanol leading to phase separation in blend.

Autonomous driving is looked upon as solution for future of automotive vehicles. The technology has tremendous possibilities to improve safety, fuel economy, comfort, cost of ownership etc. The project to develop an autonomous controller from scratch was undertaken, with objective to drive under selected test scenarios. The car, modified to drive using this autonomous controller, is able to handle these scenarios. The key scenarios include ability to successfully drive on tracks with well-marked lanes, Follow the route as per selected trip plan file, recognize and follow all traffic road signs, traffic signals en-route, identify other vehicles on the road or pedestrians in the lane and take the appropriate action. The development was carried out using frugal engineering approach. As the Autonomous Vehicle technology is still under development, the standard proven published approaches are not available.

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.

With increased vehicular traffic density a trend has been observed where customers have started preferring automatic transmission in place of its manual version. This Automatic transmission not only shifts the gear automatically, with the help of sensors and actuators, but they are also tuned for better performance of the vehicle in terms of fuel efficiency and emission. This all comes at the cost of power consumption from the battery, increment in cost, weight and complexity. The main parts of an automatic transmission include Torque Convertor, Sensors, Actuators, Transmission Control Unit (TCU) with the epicyclic gear-train being the heart of it. In terms of use in the automotive, a system of epicyclic gear-train can provide only 2 gear ratios. Ravigneaux gear-train is the modified version of epicyclic gear-train where there are two set of Planet gears and Sun gears or Ring gears thereby capable of giving 4 gear ratios with a single system.

Air pollution in India and also global warming are two major concern in the country. To address this situation, India is moving from BS-IV to BS-VI for on-road applications with 90% reduction in NOx and 50% in PM with limit on particulate number. Also moving to Trem-IV and Trem-V for off-road applications subsequently. It needs higher efficiency after-treatment systems like SCR and DPF to achieve such lower emission levels. Addition of these complex after-treatment system, severely increase the cost of diesel power plant with heavy penalty on fuel economy. Hence, it is challenge to auto industry to reduce the complexity and cost, so that it requires an alternate solution to reduce NOx and PM emissions at source to reduce cost and system complexity. Low Temperature Combustion (LTC) is a potential concept to reduce the NOx and PM emissions simultaneously.

The use of polymers in automobiles is increasing constantly and this trend is expected to continue. This clearly indicates that polymer are choice of materials in all the application sectors including in Automobile sector. The main properties in selecting the plastics materials as compared to other materials applied in automobiles are the aesthetic of automotive vehicles, their functionality and cost effective solution, as well as fuel efficiency. These materials are offer remarkable range of appealing properties, the effect of climatic conditions on the degradation and performance of these materials is not fully understood. It is necessary to know the variation of the mechanical properties of any polymer component in automobile after exposed to different atmospheric conditions before particular application. Generally when these components are subjected to weathering effects, they are prone to underperform.

In today’s automotive industry sound package material design and optimization is important considering the need for weight reduction and achieving targeted sound absorption and sound transmission loss values. As per traditional approach vehicle level noise reduction targets are defined considering flat samples, but in actual vehicle condition molded trimmed parts are used. This paper discusses about the systematic methodology developed for molded sample characterization in terms of BIOT’s properties. Effects of different parameters like area wise thickness variation, density variation on BIOT properties is studied. Comparison of BIOT’s properties of flat and molded dash sample is done to study the effect of molded structure. Using these BIOT’s properties prediction of sound absorption and sound transmission loss results carried out using FTMM approach for flat sample and SEA approach for molded sample.

Because of higher NOx and PM emissions Compression Ignition (CI) engines are slowly being replaced by gas engines in metro cities though CI engine have better thermal efficiency and emit less Carbon monoxide (CO) and Unburned Hydrocarbons (UHC) emission than SI engines. Pollutants formed during combustion, depleting fossil fuels and continuous raising fuel price pushes the research community to find new alternative fuels which can be used along with diesel or replace the diesel without making major modifications in the current engine. The objective of this research work is to derive bio-diesel fuel from the source of algae and use it as a fuel by blending with commercially available diesel fuel. Heptanol is added along with algae bio-diesel and diesel blend to improve the ignition quality of the blend. Tests were conducted on a single cylinder constant speed, water cooled stationary diesel engine with different blends proportions of heptanol-biodiesel-diesel.

A test engineer faces a series of considerations (decisions) when designing a test program to conduct service history simulation testing of full scale vehicles (structures) in the laboratory. This paper proposes a logical decision path, with pertinent discussion of tradeoffs, which is intended to serve as a design guide in this process. A good deal of the authors’ subjective opinion is included. The paper begins by presenting a model of how a test facility should interface to the total engineering process. This is important in establishing a proper division of responsibility for the validity and usefulness of test results. This is followed by a specific discussion of service history simulation testing for durability evaluation.

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.

Small single & two cylinder diesel engines, still have primitive technical design features and extensively used in India and various Asian countries to power small and light motor vehicles viz., three wheelers, light duty four wheelers. These vehicles have become inevitable for the transport for both urban and rural areas. Vehicles with small single & two cylinder engines have high market demand in commercial transport due to restrictions on entry of Heavy Commercial Vehicles (HCV) in congested cities roads. Due to ever rising market demand for higher power and torque requirement along with better fuel economy, vehicle manufacturer are developing high Brake Mean Effective Pressure (BMEP) engines or replacing single cylinder engine by two cylinder engine, similarly two cylinder engine by three cylinder engines. Further, these engines should meet the present and forthcoming stringent emission limits.

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.

In the automotive industry, there is a continued need to improve the development process and handle the increasing complexity of the overall vehicle system. One major step in this process is a comprehensive and complementary approach to both simulation and testing. Knowledge of the overall dynamic vehicle behavior is becoming increasingly important for the development of new control concepts such as integrated vehicle dynamics control aiming to improve handling quality and ride comfort. However, with current well-established test systems, only separated and isolated aspects of vehicle dynamics can be evaluated. To address these challenges and further merge the link between simulation and testing, the Institute of Internal Combustion Engines and Automotive Engineering (IVK), University of Stuttgart is introducing a new Handling Roadway (HRW) Test System in cooperation with The Research Institute of Automotive Engineering and Vehicle Engines Stuttgart (FKFS) and MTS Systems Corporation.

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.

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.