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On-board diagnostics (OBD) of diesel vehicles require various sensors to detect system malfunctions. The Particulate Matter (PM) sensor is one of OBD devices which gather information which could be critical in determining a crack in the diesel particulate filters (DPFs). The PM sensor detects PM which penetrates cracked DPFs and converts the amount of PM into electrical values. The PM sensor control unit (SCU) receives those analog signals and converts them to digital values through hardware and software solutions. A capacitive sensing method would be a stable solution because it detects not raw analog signals but electrical charges or a time constant going through the capacitive load. Therefore, amount of PM would be converted reasonable value of capacitance even though there is a little amount of PM.

This paper aims at analytical and numerical evaluation of the structure of a Baja. It will be described some load conditions to analyze the overall structure of Baja well as localized elements, in order to prevent premature failure of the vehicle during the competition and improvements in the design phase. The numerical analysis will be conducted via finite elements to establish the optimization of weight and gain performance of the vehicle. Analytical evaluation it will conducted via propositions of physics. Results obtained for the initial concept of the project and compared with the structural changes after the trial proposition will be presented. Analysis of study resulted in improvements in manufacturing reducing weight. Also it was expected to increase the structural performance associated to a better understanding of the vehicle as a whole.

Fuel consumption of road cards has been a main issue for the global automotive industry. Engineering tools, such as wind tunnels and computational fluid dynamics (CFD), have been employed for vehicle design, intending to achieve more aerodynamic efficiency. However, wind tunnels are very expensive facilities. Conversely, CFD technique rises as the best cost-effective tool for solutions on aerodynamics. This paper presents the influences of numerics and brief analysis of the intrinsic turbulent flow over a 3D realistic car model. The objective is to provide a significant cost-benefit of numerical parameters to the automotive industry in the development of road cars. Besides the validation from an unsteady-state simulation over a full car domain, the simplification of the domain by half and the steady-state regime were found to provide an acceptable approach for automotive simulation.

In engineering development, simulation methods are frequently used to perform thermal and mechanical stress components analysis. In brake systems, where the components are exposed to mechanical and thermal loads, the numerical analysis is very helpful. Once a numerical model for brake assembly is available, it will be possible to understand the effects of successive brake applications on the temperature distribution in drum brake’s friction materials. This is a fundamental aspect to determine, for instance, the thermal stress distribution which is related to the warming and cooling of the brakes. In this work, an analytical solution to calculate stabilized temperature was used to establish a heat flux through a pneumatic S cam drum brake’s friction material applied to a numerical model in a finite element analysis.

Butanol is an important industrial chemical and a promising biofuel. However, for the butanol applications in engines, studies are not as extensive as the case of ethanol or biodiesel. Therefore, there is a lack of information regarding the thermodynamic and combustion parameters of internal combustion engines operation using butanol fuel. To evaluate the combustion calculations and the thermodynamic simulation of internal combustion engines, several references from the literature can be used to obtain the thermodynamic and combustion routines. The most complete models are based on polynomials curve fits to the thermodynamic data (specific heat, enthalpy and entropy) of the fuels. The goal of this study is to evaluate the coefficients of the thermodynamic property curves of butanol fuel, so that the fuel can be included in the routines for internal combustion engines calculations.

The rapid growth of Electric Vehicles (EV’s) and Hybrid Electric Vehicles (HEV’s) has increased the concern that the relative silence of these type of vehicles will result in an increased risk to pedestrian safety. A practical solution to this problem is to add artificial sounds to EV's to aid their detection by pedestrians and other vulnerable road users. Acoustic warning systems for EV’s should increase pedestrian safety and simultaneously produce a small impact on environmental noise levels. This paper shows the main advantage of using a directive acoustic source implemented as a beamforming loudspeaker array in an EV to increase pedestrian safety and control the effect on noise pollution. An example of such a system has been implemented in a Nissan Leaf vehicle and its performance in realistic situations has been assessed.

The hydrodynamic thrust bearings has been the subject of several studies in the scientific environment. In the hydrodynamic lubrication the surfaces are completely separated by the lubricating film, and therefore it is the most desirable type of lubrication. The lubricant should be chosen in order to reduce power losses by viscous dissipation. The work aims to analyze the power loss by viscous dissipation for various types of lubricating oils. It was investigated a six pivoted-pad thrust bearing in a rotation range between 1500 rpm and 3000 rpm. Eleven different types of lubricating oils were analyzed. It was possible to observe the net power loss - in function of the lubricant type - for each of the thrust bearings located in an automobile. The cost associated with this loss of potency was also obtained. The results showed that the appropriate selection of the lubricating generates an increase of 50% in power gain.

The increasing use of embedded electronics in aerospace and automotive vehicles increases the designers' concern regarding the reliability of the components as well as the reliability of their interconnections. The discussion about the most appropriate method for assessing the reliability of solder joints for a given application is an ever-present theme in the literature. Several methods of prediction have been developed for assessing the reliability of solder joints. The standard method established by the industries for assessing reliability of solder joints is the thermal cycling. However, when the thermal distributions in real applications are studied, particularly in some electronic components used in on-board electronics of space systems, the thermal cycling does not represent what actually happens in practice in the packaging.

This work aims the implementation of a system able to estimate the occupancy rate (number of occupants) inside motor vehicles. This system is based on a Wireless Sensors Network using the standard IEEE 802.15.4, connected to a computer. The estimation of occupancy rate inside the motor vehicle can provide better energy efficiency and therefore optimize fuel and battery consumption.

The paper talks about the migration phenomenon that is observed in gears. The phenomenon discussed here is that observed on hypoid gears which due to their high spiral angles cause the issue to be more sensitive, but the analogy to other gears is applicable. Mahindra manufactures hypoid gear sets for its axles in-house that go on a wide range of its products; with performance benefits also come the stringent quality requirements for hypoid gear sets. Migration is the phenomenon that causes the furling or unfurling of individual gear teeth with respect to each other. This in effect causes the circular tooth spacing between two teeth to become non-uniform. This has a direct effect on the performance of the mated gear set.

The paper talks about machining techniques and solution approaches while machining Aluminium grade gearbox housings. Mahindra’s next generation gearbox housings are made totally of Aluminium; along with the higher strength to weight ratio that comes with using Aluminium come highly optimized ribbed structures that aid in achieving the said strength. While machining such Aluminium structures, it is imperative that the clamping forces do not load the component in ways it is not intended to. The paper talks about finish machining and proving out a semi-finished gearbox housing set (front, intermediate plate and rear) on a conventional Horizontal Machining Center (HMC). The input to the machine is the semi-finish housing that is already machined before with stock for finish operations.

The biggest challenge in vehicle BIW design today is to make a light, cost effective and energy absorbing structure. With the increasing competition as well as increasing customer awareness, today’s vehicle has to satisfy several aesthetic and functional requirements besides the mandatory regulatory requirements. While working on global platform, it is challenging to comply with both pedestrian protection and low speed bumper impact (ECE-R42) and at the same time meeting the styling intent of reducing the front overhang. Pedestrian lower leg compliance demands space between bumper member and bumper, a condition that reduces the space available for energy absorption during low speed impact (ECE-R42). Therefore, reduction in front overhang poses a problem in meeting both the requirements with limited space. This paper outlines vehicle case study in order to optimize the design of Bumper Beam structure, for complying with regulatory requirements while satisfying the styling intent.

Composite structures play a vital role in the automobile industry. Use of composites like CFRPs in automobiles poses various problems to engineers. CFRP components are not simple to model in comparison to traditional engineering materials like aluminium, steel etc. One of the main reason is that the composite materials generally do not behave in an isotropic manner but rather behave in an anisotropic or orthotropic manner. These anisotropic and orthotropic mechanical behaviors are more difficult to predict as compared to isotropic behaviors. This problem is solved using finite element analysis (FEA) packages to model complex composite material and predict their behavior. The paper discusses about the propagation of stresses within the composite laminates using FEA in Abaqus for different lamina stacking directions. The results obtained are verified using Theoretical Analysis in MATLAB.

Kinematic inputs such as camber, caster variation are very important for design of any suspension setup. Usual procedure is to get these inputs from kinematic software. But every designer cannot have this software & one has to learn them too. We have developed a method for kinematic analysis of McPherson strut type suspension which can be implemented on easily available and familiar software like MS Excel. Results obtained are in correlation with results from commercially available mechanism tools such as Pro mechanism. All links in suspension layout are considered as rigid. Vector calculus and other mathematical methods have been used to come up with final solution. Inputs required for mathematical program are suspension hardpoints, Lower arm angle from design orientation as wheel travel input and Rack stroke as steering input.

Biodiesel can be considered as one of the alternative fuels for diesel engine vehicles in which the direct usage of biodiesel as a fuel is often restricted due to their high viscosity, poor atomization, incomplete combustion and carbon deposits on fuel injectors, more over biodiesels emits more NOx emissions owing to their high oxygen content. In order to reduce these effects biodiesel emulsion techniques have been used recently. This paper present the influence of adding Alumina nano particles to Karanja biodiesel emulsion fuel and study of performance and emission characteristics on a diesel engine. The investigations have been carried out in three phases on computerized single cylinder diesel engine using neat Karanja biodiesel (KBD), neat KBD emulsion fuel and Alumina blended KBD emulsion fuel. The KBD emulsion fuel has been prepared in the proportion of 93% KBD , 5% distilled water , 2% of surfactants (Span80 and Tween80) by volume to maintain hydrophilic-lipophilic balance.

In Modern Passenger Car Braking system, Disc brake plays a vital role in providing better performance and safety, in which brake pads are most critical part to decide the overall brake performance. In such brake pads, there are some technical challenges such as wear rate, abnormal noise & environmental issues with existing asbestos material. Hence we made a research to furnish suitable eco-friendly & cost effective solution. The main objective of this paper is to introduce asbestos-free automotive organic brake pad. Our research work intends to make organic brake pad by using natural fibre with organic ingredients such as kenaf and other composite materials in right proportion. Kenaf fibre is one of the natural fibres, which will improve heat resistance and strength of the brake pad. Initially, kenaf fibre is mixed with other composite materials and compacted at an optimal pressure by using hand-press machine.

Primary function of the inverter in an Electric or Hybrid Electric vehicle (EV/HEV) is to generate required AC voltage from high voltage battery to drive Electrical machine (EM). Being part of power-train of the vehicle, inverters (or hybrid control units (HCU)) are safety related electronic control units (ECU) due to the severity of the accidents/incidents that could result if the ECU is not functional as intended. Therefore it is necessary to develop the inverter in accordance with applicable safety standards. The standard ISO 26262 in particular addresses the complete development cycle of safety related automotive products. OEMs now mandate the strict adherence to ISO26262 standard for such ECUs. This paper describes how safety principles are realized in the hardware modules of inverter, which are responsible for the functional safety adherence.

Increasing demand of Electric and Hybrid vehicles questions more about Reliability and Lifetime of electronic circuits associated with them. It is very important for a hardware circuit designer to evaluate if module will last the expected lifetime. This paper elaborates the methods and steps to find the expected lifetime of critical components; and to decide whether Hybrid Power Electronics Unit (PEU) will meet the OEM requirements on lifetime. Accelerated thermal stress method is used to determine the required High Temperature Operational Life (HTOL) hours for given thermal profile of Hybrid vehicle passenger car in driving (8,000Hrs), charging(30,000Hrs) and total lifetime (38000Hrs ≈ 15Years). Example calculation of required HTOL hours against expected lifetime for critical component from Hybrid ECUs is explained in this paper. Also inclusions and exclusions of this method in evaluating lifetime assessment are also discussed here.

With increasing growth of vehicular population, there is an increasing demand for raw materials. This has added strain to the available resources, which is becoming more and more unsustainable. As a result, search for sustainable materials are continuously happening in our industry and there is a strong focus from everyone to incorporate more and such materials. One way of doing so, is by blending naturally available materials like fibers, with polymers. In this study, naturally available Coconut fibers have been blended successfully with Polyurethane foam, thereby improving the green footprint of the vehicle. Coconut fibers are naturally occurring fiber extracted from the husk of the coconut. Polyurethane foam is the most versatile polymeric foam used in several places of automobile for reducing the Noise, Vibration & Harshness. The composite was manufactured using reaction injection molding technique by reacting polyol with iso-cyanide.

Biodiesel is an alternative fuel for diesel which is made through a chemical process which converts vegetable oils and fats of natural origin into fatty acid methyl esters (FAME). The most usual method to transform Bio-oil into biodiesel is Transesterification that can be carried out using different catalyst systems. Jatropha is second generation, non-edible oil and can be used for producing biodiesel. The Transesterification reaction consists of heating jatropha oil with proper concentration of methanol at appropriate temperature in the presence of catalyst. After reaction, the mixture is allowed to settle down for 8-10 hrs. Two separate layers, top layer of biodiesel and lower layer of glycerol will form, which can be separated. Reaction temperature, amount of methanol, catalyst and reaction time are important parameters which decide yield and quality of biodiesel.