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The purpose of this study is to conduct dynamic seat pressure mapping on vehicle seats during its operation on different test tracks under ambient environmental conditions for a defined speed. The test track comprises of pave roads, high frequency track, low frequency track and twist track. The variations in pressure distribution on seat during diverse road load inputs help to understand the seat cushion and back comfort for unique percentiles of human subjects ranging from 50th to 95th percentile population. For conducting the study, a sport utility vehicle (SUV) loaded with leatherette seats has chosen. Totally six participants (human subjects), five male and one female selected for the study based on their BMI (Body mass index) and body morphology. Pressure mats suitable for taking dynamic load inputs and able to log the data at a defined sampling rate mounted on seats and secured properly. The pressure mats should cover the seat cushion, bolster areas and back seat completely.

The implementation of TREM/CEV 5 emission norms on farm equipment will bring in cost pressure due to the need for exhaust after treatment systems. This cost increase needs to be reduced by bringing in more efficient and effective processes to shorten the development phase and to provide better fuel efficiencies. In this work ETAS ASCMO Online DoE with Constraint Modelling (ODCM) was applied to execute smart online DoE on a new common rail diesel engine with EGR, whose exact bounds of operation was not available. A Global test plan with ASCMO Static was created without much focus on detailed constraints of engine operation, other than the full load curve. The parameters which were selected were Speed, Torque, Rail Pressure, Main Timing, EGR Valve Position, Pilot Separation and Quantity and Post Quantity and Separation. For these parameters, the safe operating bounds were not available. This ASCMO Static test plan is automated and executed on engine test cell with ETAS INCAFlow.

Ride is essentially the outcome of coupled dynamics of various involved sub-systems which make it too complex to deal analytically. Tires, amongst these, are known to be highly nonlinear compliant systems. Selection of tires specifications such as rated tyre pressure, etc. are generally decided through subjective assessment. While experts agree that tyre pressure affects the attributes such as ride to a noticeable degree, the quantification of the change often remains missing. In the current work, vibration levels of various sub-systems relevant to ride in an SUV are measured for three different tyre pressures at different speeds over the three randomly generated roads. For the purpose, artificial road profiles of classes A, B and C are synthesized from the spectrum of road classes defined in ISO 8608:2016 and reproduced on a four-poster test rig.

A competitive market and shrinking product development cycle have forced automotive companies to move from conventional testing methods to virtual simulation techniques. Virtual durability simulation of any component requires determination of loads acting on the structure when tested on the proving ground. In conventional method wheel force transducers are used to extract loads at wheel center. Extracted wheel center forces are used to derive component loads through multi-body simulation. Another conventional approach is to use force transducers mounted directly on the component joineries where load needs to be extracted. Both the methods are costly and time-consuming. Sometimes it is not feasible to place a load cell in the system to measure hard point loads because of its complexities. In that case, it would be advantageous to use structure itself as a load transducer by strain gauging the component and use those strain values to extract hard point loads in virtual simulation.

In today’s cost-competitive automotive market, use of finite element simulations and optimization tools has become crucial to deliver durable and reliable products. Simulation driven design is the key to reduce number of physical prototypes, design iterations, cost and time to market. However, simulation driven design optimization tools have struggled to find global acceptance and are typically underutilized in many applications; especially in situations where the algorithms have to compete with existing know-how decision making processes. In this study, systematic multi-phase approach for optimization driven design is presented. Approach includes three optimization phases. In first phase, topology optimization is performed on concept BIW design volume to identify critical load paths. Architectural inputs from topology are used to design base CAD.

Virtual assessment of an occupant postural ergonomics has become an essential part of vehicle development process. To design vehicle for different market is one of the primary reason for manufacturers using digital tools to address the specific needs of the target market including cultural background, road and traffic conditions. RAMSIS is a widely used software for creating digital human models (DHM) of different target population which allows manufacturers to assess design with unique customer requirements in product design. Defining these requirements with RAMSIS human module helped development team to accurately define occupant targets such as occupant space, visibility and reachability etc. Occupant behavior and usage scenario are factors which are unique to target market and they influence the occupant posture and usage pattern inside the vehicle. This paper defines the methodology towards the development of Indian Digital Simulation model for vehicle ergonomic evaluations.

The life of a two-wheeler and its parts depend much on its usage during its years of running. The quality of its parts determine the life and efficiency; however the handling of the two-wheeler also plays a major role in estimating it's life and other performance parameters. Hence, it is beneficial to have an efficient system which enhances the life of a two-wheeler and also gives better mileage. This paper constitutes an efficient drive pattern system which addresses the above. This system consists of two main parts: the data collection system and an Android-based mobile application which runs on a mobile phone. The data collection system collects data from various sensors on the vehicle and then the data is processed and sent to the mobile phone of the rider during the run time of the two-wheeler. The application uses this data to depict useful information like drive pattern and various indicators.

This paper establishes quick and accurate methods to experimentally determine the rigid body properties of a powertrain unit namely, the centre of gravity, the moment of inertia and the torque roll axis and also the rigid body dynamics of mounting system such as the rigid body modes, kinetic energy distribution, and elastic roll axis. The centre of gravity is determined using single point suspension and laser pointer to locate the axis passing through the centre of gravity. A special unifilar pendulum test rig is developed for determining the moment of inertia where an accelerometer measures the rotational oscillations for a given time period and the moment of inertia is determined by solving a set of inertial ellipsoid equations. An easy method of reorienting the powertrain is demonstrated in this paper.

Regulations on pedestrian safety have been introduced globally since the year 1990 and in India it will have to be met around the year 2016. Process of making vehicle compliant to this regulation requires rigorous design development and testing. Testing involves propelling head-forms (Child and Adult) on bonnet at 35 km/h and 40 km/h and leg-forms (Upper and Lower) on bumper at 40 km/h according to the different National / International / NCAP regulatory requirements A pedestrian protection test rig has been indigenously designed and developed in-house to perform pedestrian protection impact testing in-house. The paper describes the salient features of the pedestrian protection test rig, its functioning, operation and process of acquiring the data for determination of the values required by crash safety regulations.

Validation of vehicle structure is at the core of reduction of product development time. Robust and accelerated validation becomes an important task. In service the vehicle is subjected to variable loads. These act upon the components that originate from road roughness, manoeuvres and powertrain loads. Majority of the body in white and chassis structural failures are caused due to vertical loading. Measured road load data in test track have variable amplitude histories. These histories often contain a large percentage of small amplitude cycles which are non damaging. This paper describes a systematic approach to derive the compressed load cycle from the measured road load data in order to produce representative and meaningful yet economical load cycle for fatigue simulation. In-house flow was developed to derive the compressed load time history.

This work discusses about the emission development of a 4 cylinder inline 3.3 liter CRDe to meet BS III emission norms applicable to 3.5 Ton and above category and upgradable to BS IV emission by suitable after treatment. This engine is developed from a 3.2l mechanical pump engine. During development the focus was on the usage of higher swept volume, selection of engine hardware like piston bowl, turbocharger, injectors and optimization of the injection parameters. A cost-effective solution for meeting the BS III norms in the LCV category without application of EGR and exhaust after treatment even though there is 15% increase of the power rating and 10% increase in Peak torque of the engine. Injection parameters like injection timing, injection quantity and pilot injection were optimized to meet the emission target.

Reducing the vibrations in the powertrain is one of the prime necessities in today's automobiles from NVH and strength perspectives. The necessity of 4×4 powertrain is increasing for better control on normal road and off-road vehicles. This leads to bulky powertrains. The vehicle speeds are increasing, that requires engines to run at higher speeds. Also to save on material costs and improve on fuel economy there is a need for optimizing the mass of the engine/vehicle. The reduced stiffness and higher speeds lead to increased noise and vibrations. One more challenge a powertrain design engineer has to face during design of its transmission housings is the bending / torsional mode vibrations of powertrain assembly. This aggravates other concerns such as shift lever vibrations, shift lever rattle, rise in in-cab noise, generation of boom noise at certain speeds, etc. Hence, reducing vibrations becomes an important and difficult aspect in design of an automobile.

This paper describes application of Design of Experiments (DOE) technique and optimization for mass reduction of a Sports utility vehicle (SUV) body in white (BIW). Thickness of the body panels is taken as design variable for the study. The BIW global torsion, bending and front end modes are key indicators of the stiffness and mass of the structure. By considering the global modes the structural strength of the vehicle also gets accounted, since the vehicle is subjected to bending and twisting moments during proving ground test. The DOE is setup in a virtual environment and the results for different configurations are obtained through simulations. The results obtained from the DOE exercise are used to check the sensitivity of the panels. The panels are selected for mass reduction based on the analysis of the results. This final configuration is further evaluated for determining the stiffness and strength of the BIW.