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In the pioneering sectors of design and development, industries are looking for computer integrated solutions for product development; especially in aerospace industries where the demands for reduction in the development cycles and prototyping iterations. Generative design and topology optimization are the recent tools for achieving the desired design solutions. Topology optimization aims to find an ideal structural configuration within the given design domain with various constraints, objectives, and boundary conditions. In this study, topology optimization is used as a design tool in the development phase of a component. An efficient methodology is developed based on topology optimization for regeneration of a tertiary components. The topology optimization approach used in this research is divided into three main stages: modelling, optimization and regeneration.

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.

The main objective of the study is to design and analyze casing and supports of a transmission system for an electric vehicle. The system comprises of motors as the power source, constant mesh gear box coupled with limited slip differential as the power transmitting source. The space occupied by the transmission system is a foremost constraint in designing the system. The wear and tear in the system is caused by the gear meshing process and transmission error which lead to failure of the transmission system. This internal excitation also produces a dynamic mesh force, which is transmitted to the casing and mounts through shafts and bearings. In order to overcome such issues in a transmission system, a gear box casing, differential mounts and motor mounts have been designed by the use of CAD-modeling software “SOLIDWORKS”. The designs were imported to FEA software “ANSYS” for carrying out static structural analysis.

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.

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.

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.

5 belt wind tunnels are the most common facility to conduct the experimental aerodynamics development for production cars. Among aerodynamic properties, usually drag is the most important development target, but lift force and its front/rear balance is also important for vehicle dynamics. Related to the lift measurement, it is known that the “pad correction”, the correction in the lift measurement values for the undesirable aerodynamic force acting on wheel belt surface around the tire contact patch, must be accounted. Due to the pad correction measurement difficulties, it is common to simply subtract a fixed amount of lift values from measured lift force. However, this method is obviously not perfect as the pad corrections are different for differing vehicle body shapes, aerodynamic configurations, tire sizes and shapes.

The purpose of this paper is to present the past and present concepts of mechanical test optimization, which means the adjustment of a test machine command signal to achieve desired amplitude and mean levels. In particular, the methods of null pacing, dynamic frequency control, classical amplitude control, and maximum velocity limiting / control are discussed along with their respective application areas, advantages and disadvantages. Also, the factors of data verification and over-complication of the test are noted.

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.

In the present study, an aluminium based nanocomposite, reinforced with 2 wt. % aluminium oxide (Al2O3) is developed through stir casting method. These hard ceramic particles also influence the material removal rate (MRR), electrode wear rate (EWR) and surface finish (Ra) in an electro-discharge machining (EDM) process. In this work, EDM of Al 7075/2 wt. % Al2O3 nanocomposite is carried out using copper and brass electrodes using Taguchi L18 array. The percentage contribution of each process parameter on the response variables was determined using analysis of variance (ANOVA). Multi-response signal to noise ratio (MRSN) and the optimum combination levels for the input parameters was obtained using Taguchi’s parametric design. MRR and surface roughness are substantially improved when machining is performed at optimized conditions.

New process development of forging component require lot of process knowledge and experience. Even lots of trial-and-error methods need to be used to arrive at optimum process and initial billet dimensions. But with help of reliable computer simulation tools, now it is possible to optimize the complete process and billet dimensions without a single forging trial. This saves lot of time, energy and money. Additionally, simulation gives much more insight about the process and possible forging defects. In this paper, a complete forging process was needed to be designed for a complex component. With the help of computer simulation, the complete conventional forging process and modified forging process were simulated and optimized. Forging defects were removed during optimization of the process. Also billet weight optimization was carried out. Deciding the pre-forming shape of the billet was the main challenge.

Future emission limits for off-highway application engines need advanced power train solutions to meet stringent emissions legislation, whilst meeting customer requirements and minimizing engineering costs. DI diesel engines with four valves per cylinder are widely used in off- highway applications because of the fundamental advantages of higher volumetric efficiency, lower pumping loss, symmetric fuel spray & distribution in combination with the symmetric air motion which can give nearly optimal mixture formation and combustion process. As a result, the fuel consumption, smoke levels and exhaust emissions can be considerably reduced. In particular, the four-valve technology, coupled with mechanical low pressure and electronic high pressure fuel delivery systems set different requirements for inlet port performance. In the present paper four valve intake port design strategies are analysed for off highway engine using mechanical fuel injection systems.

An analytical approach to developing motorcycle suspensions is presented. Typical uncontrolled and subjective evaluations that place limits on suspension development are curtailed through the use of a laboratory-based road simulation technique, which evaluates vehicle ride quality. Ride comfort is calculated using a specifically tailored NASA model after primary and secondary frequency regimes have been established for this type of motorcycle. Correlation between road and laboratory simulation is measured and compared to the road data variance. A designed experiment evaluates changes in ride quality as a function of suspension and tire pressure adjustments. Various suspension settings are repeated on the simulator and corresponding ride numbers are calculated for both environments. An analysis is performed to correlate ride quality improvements on the simulator with ride quality improvements in the field.

Advanced driver-assistance systems (ADAS) are becoming an essential part of the modern commercial automobile industry. Vehicle handling and stability are determined by the yaw rate and body slip of the vehicle. This paper is a comparative study of a nonlinear vehicle stability control algorithms for steering control based on two different controllers i.e. fuzzy logic based controller and PID controller. A full vehicle 14DOF model was made in Simulink to simulate an actual vehicle. The control algorithms are based on a two-track 7-DOF model with a non-linear tire model based on Pacejka “Magic tire formula”, which was used to establish the desired response of a full vehicle 14DOF model. It was found that the fuzzy logic-based control algorithm demonstrated an overall superior performance characteristic than a PID based control algorithm; this includes a significant decrease in time lag and overshoot.

Antiroll bar plays an important role in rollover stability of the vehicle. But not only does it limit the vehicle roll during cornering, but also alters the lateral load transfer between the tracks, which in turn affects the cornering performance of the vehicle. This paper deals with the design and mathematical modeling of antiroll bars to reduce the body roll of the vehicle from 1.5°/g to less than 1.0°/g. Rear bar uses a conventional torsion type bar but the front anti roll mechanism is an unconventional antiroll bar using a rotating double cantilever mechanism. Mathematical modeling is done for pushrod rod actuated antiroll mechanisms to simulate its non-linear roll rates. Antiroll bars for front and rear are designed for the calculated stiffness. Finite Element Analysis of antiroll bar and its components is done and the mechanism is tested on the vehicle. Steady state tire model parameters are generated by curve fitting tire testing data into pacejka coefficients.

A model for Hybrid electric vehicle power train with parallel hybrid braking system has been constructed. The hybrid vehicle utilized is based on integrated motor assist power train developed by Honda co utilized in Honda Insight car. The model is implemented using empirical formulation and power control schemes. A power control strategy based on throttle position (% throttle) and brake pedal position (% braking) is used. It incorporates the parallel hybrid braking system for the hybrid electric vehicle. The model allows for real time evaluation of wide range of parameters in vehicle operation as HEV without parallel hybrid braking system (PHBS) and with PHBS. Due to regenerative braking the structure design and control of braking system for HEV is different from conventional vehicle. The PHBS is the good option to provide safety of the vehicle and simultaneously recover reasonable amount of braking energy.

The objective of this study is to develop, demonstrate and validate the methodology of external aerodynamic analysis of a State Road Transport bus for prediction of drag coefficient and its impact on fuel consumption with experimental validation. It has been verified that vehicle consumes around 40% of the available engine power to overcome the air drag. This gives us a huge scope to study the effect of aerodynamic drag. Baseline model of State Road Transport Bus was evaluated for estimating fuel consumption using Computational Fluid dynamics (CFD) methodology. The CFD results were validated with the experimental data with less than 10% deviation. Bus design was optimized with an objective of reducing the fuel consumption with parameters like angle of windshield, rounding and tapering corners and rear draft angle. Optimized bus design is also ensured to meet functional specifications as per AIS052.

Dual fuel operating strategy offers great opportunity to reduce emissions like particulate matter and NOx from compression ignition engine and use of clearer fuels like natural gas. Dual-fuel engines have number of potential advantages like fuel flexibility, lower emissions, higher compression ratio, better efficiency and easy conversion of existing diesel engines without major hardware modifications. In view of energy depletion and environmental pollution, dual-fuel technology has caught attention of researchers. It is an ecological and efficient combustion technology. This paper summarizes a review of recent research on dual-fuel technology and future scope of research. Paper also throws light on present limitations and drawbacks of dual-fuel engines and proposed methods to overcome these drawbacks. A parametric study of different engine-operating variables affecting performance of diesel-CNG dual-fuel engines vis-à-vis base diesel operation is also summarized here.

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.