Refine Your Search

Topic

Author

Affiliation

Search Results

Technical Paper

Front Suspension Joint Integrity Analysis for Addressing Noise Issue Due to Torque Loss at Lower Control Arm Joint

2021-10-01
2021-28-0246
The lower control arm (LCA) is a part of the front suspension system which is mounted on chassis with flexible rubber bushing through-bolted joint which allows the control arm to swing up and down, absorb road bumps and reduce noise and vibrations as front wheels roll over bump or potholes. In bolted joints, torque is applied so as the joint develops a certain preload that is higher than the external loads and losses acting on the joint. But the loss of preload is evident over time which causes quality problems, reworks, or even joint failures. While moving over speed breakers/obstacles abnormal squeak noise is observed in the vehicle due to torque loss in the LCA joint. The intent of this study is to determine preload requirements in LCA joint and various factors contributing to preload loss by performing joint integrity analysis in CAE. Road load data acquisition (RLDA) with Wheel Force Transducer (WFT) is performed for different testing tracks.
Technical Paper

Automatic Alert System to Enable Safe Ride and to Prevent Accidents in Two Wheelers and Three Wheelers

2021-10-01
2021-28-0233
In Midway accidents are general in nature in the highways. Vehicles meeting the accidents are not saved in a faster way for the rescue. This system generates the signal from the pressure sensor located under the seat during the operation of the vehicle. An Electronic Control Unit (ECU) has been deployed to provide the information about the passenger wearing helmet or not mobile phone contacts and the nearest safety officer with respect to the Global Positioning System installed in the vehicle. The signal from the hand bar sensor has been generated for the two-wheeler and the driver - cum pillion rider (TWDPR) such that the abnormality of the TWDPR rider and pillion rider is indicating the dearer contacts and the health the centres for the rapid recovery of the vehicle met with accident.
Technical Paper

Component S/N Curve Testing Methodology for Exhaust System Validation

2021-09-22
2021-26-0451
The exhaust system design and development need to be more flexible and easily adaptable for the requirement of dynamic changes to meet the upcoming emission and noise regulations. Durability of exhaust system components are evaluated through conventional bending moment testing using specified standard load conditions. Road load re-production test is an improvement of the conventional approach to predict component weld durability. It involves the systematic and sequential process of acquiring road load data such as sensor instrumentation, strain measurement at the test track, data processing and input to Bi-Ax testing. S/N Curve testing is introduced recently as an alternate method to minimize the use of road load reproduction testing. It involves prediction of rough force using transient response analysis followed by Bi-Ax testing for the derived high and low load forces to meet the target number of cycles to failure.
Technical Paper

Test Methodology Development on Multi-Purpose Bracket for HCV Application

2021-09-22
2021-26-0467
In the modern automotive sector, durability and reliability are two terms of utmost importance and relevance. The ever improving standards and cut throat competition has led to customers expecting highly reliable products at low costs. Any product that fails within its useful life leads to customer dissatisfaction and affects the OEM’s reputation. To eradicate this, all automotive components undergo stringent validation protocol, either in proving ground or in lab. Multipurpose bracket is one of the most important and critical aggregate in the vehicle assembly. It encompasses various mounting components such as FUPD bracket, steering mounting bracket, front spring front bracket, cab mount bracket, cab tilt cylinder mounting bracket, front cross member, footstep bracket and bumper. All these components experience various degrees of vibration and fatigue during its running period.
Technical Paper

Front Axle Kingpin Bush - Evaluation of Wear in Operating Conditions

2021-09-22
2021-26-0473
In automobiles, front axle assembly is a main load bearing member and houses steering linkages. Front axle assembly has two main parts namely axle beam and axle arm, interconnected by a kingpin. This kingpin allows the rotation of axle arm during steering events. To avoid metal to metal contact between axle arm and kingpin, bushes are housed on the top and bottom half of the axle arm & in axle beam. Due to radial load and steering rotation, as a weak member, bushes will wear out faster. This affects the proper functioning of steering mechanism. Hence, the bushes need to be evaluated prior to its implementation in vehicle. In general, bushes are evaluated using Pin-On-Disc test as a comparative study, but it does not simulate exact boundary conditions as in vehicle. Next option is vehicle level validation but leads to more testing time and cost. Hence, as an optimized solution, the same vehicle operating conditions can be replicated in component level testing.
Technical Paper

Coastdown Road Load Coefficients of Passenger Vehicles - Variation Analysis and its Correlation with Temperature

2021-09-22
2021-26-0487
Road Load parameters (rolling resistance and aerodynamic drag) of a vehicle have strong impact on overall Vehicle Emissions and Fuel Economy. The road load coefficients are simulated on chassis dynamometer to carryout emission and fuel economy measurement and are hence required to be found beforehand. A realistic measure of road load parameters can be obtained by conducting a coastdown test. Coastdown test results are hugely impacted by various environmental parameters like ambient temperature, atmospheric pressure, wind speed etc. Though performed in standard boundary conditions, results of multiple tests performed on a vehicle vary from one another due to variations in the mentioned environmental parameters over and above standard test to test variation. This paper aims at studying the variation in test results due to ambient temperature as one of the parameters responsible.
Technical Paper

Multi Axis Fatigue Test of Lift Axle Assembly through Real Time Simulation Abstract

2021-09-22
2021-26-0486
This paper discusses the test setup and methodology required to validate complete lift axle assembly for simulating the real time test track data. The correlation of rig vs track is discussed. The approach for reduction of validation time by eliminating few of the non-damaging tracks/events, its correlation with real life condition is discussed, and details are presented. With increased competition, vehicle development time has reduced drastically in recent past. Bench test procedure using accelerated test cycle discussed in this paper will help to reduce development time and cost. Process briefed in this paper can also be used for similar test specification for other structural parts or complete suspension system of heavy commercial vehicles.
Technical Paper

A 1:3 Small Scale Vehicle Model Investigation in Small Scale Wind Tunnel and Correlation with Full Vehicle Testing

2021-09-22
2021-26-0493
In present study a comparative investigation and correlation attempted on small scale vehicle model for aerody-namic drag performance at small scale wind tunnel test facility in India vs full vehicle tested at globally know and accepted full scale test facility in Pininfarina, Italy. Current investigation aims to assess the small-scale wind tunnel suitable for testing 1:3 small scale car models A scale model of 1:3 scale size was tested in small scale wind tunnel (at IISC,Bengaluru, India) having test section area of 11.68 Sq. m. To understand the overall vehicle aerodynamic drag performance small scale model was test-ed for different configurations such as baseline, spoiler removal, underbody cover and different yaw condition. To understand the correlation between small scale vs full vehicle’s aerodynamic performance one actual vehicle was also tested at full scale wind tunnel Pinifarina Italy.
Technical Paper

Road-Lab-Math (RLM) Strategy for Improving Vehicle Development Efficiency

2021-09-22
2021-26-0193
In today’s Indian automotive industry, vehicles are becoming more complex and require more efforts to develop. Also, new and upcoming regulations demand more trials under varied driving conditions to ensuring robustness of emission control. Combined with expectations of customer to get new products more frequently, requires solutions and methods that can allow more trials with required accuracy to ensure compliance to stricter regulation and delivery a quality product. This translates into more trials in less time during the development life cycle. Recently, to overcome above challenge, there has been focus on simulating the vehicles trials in engine bench environment. ‘Road to Lab to Math’ (RLM) is a methodology to reduce the effort of On-road testing and replace it with laboratory testing and mathematical models. Also, on-road testing of prototype vehicles is expensive as it requires physical parts.
Technical Paper

Study of Vehicular CO2 Variations in MIDC

2021-09-22
2021-26-0196
With introduction of CAFÉ norms in India from Apr’17, the manufacturer of all M1 Category vehicles (not exceeding 3,500kg GVW) has to ascertain that they comply with Annual Corporate Average CO2 Target as defined in AIS-137 regulation which is becoming stricter in future. Hence CO2 emissions are becoming one of the major focus parameters during vehicle development. The assessment of CAFÉ compliance involves multiple steps. Firstly, test agency provides Type Approval and Conformity of Production emission test reports to the Designated Agency. Accordingly, every manufacturer submits Fuel consumption report/Passbook to the Designated Agency on annual basis. After verification of all data, the Designated Agency issues a status of compliance to the Manufacturer. Such detailed assessment protocol presents a huge challenge for any manufacturer in maintaining the consistency/accuracy of CO2 produced by manufactured vehicles within the Type Approved Limit.
Technical Paper

Modeling and Thermodynamic Analysis of Li-Ion Battery for EV Using MATLAB

2021-09-15
2021-28-0119
LI-ion battery cells used in EVs are subjected to different charge and discharge rates due to the varying and fluctuating demand for power by the user. The different C rates in turn will have variation in internal heat profiles. This paper will provide a prediction of the total heat generated in cells from joule heat and reaction heat. The project has an experimental method to measure joule heat by performing HPPC tests at different C rates and at different cell surface temperatures. To measure reaction heat an experimental method is designed to test cells at different temperatures. Calculation of entropic heat coefficient to be done from open circuit voltage vs temperature graph. MATLAB Simulink model used to predict the temperature at a specific time by providing C rates. Simulation of the thermodynamic behavior of the cell is done on calculated heat generation values. Reaction Heat part cannot be ignored in calculation of total heat generation by cell.
Technical Paper

Autoliv’s Sound and Vibration Laboratory for Automotive Safety Component Development

2021-08-31
2021-01-1095
The new sound and vibration laboratory at Autoliv’s Ogden Technical Center (OTC) was purpose-built with a focus on automotive safety restraint product development (air bags, seat belts, steering wheels, etc.). The laboratory requirements stem from the continued industry trend of quieter vehicles which drives the need for components with extremely low levels of rattle noise. The laboratory at OTC complements similar Autoliv testing facilities around the world. Test articles range from several cubic inches up to approximately one cubic foot and contain varying degrees of moving elements. With the new laboratory at OTC, Autoliv can test new product designs earlier in the development process and obtain test results and feedback faster. The function of the OTC test lab is vibration-induced rattle noise; shake components with a known input and measure the resulting noise.
Technical Paper

Development Work for a New Damping Standard SAE J3130

2021-08-31
2021-01-1122
Standards organizations develop standards depending on the need in the market place. With the change in vehicle design, lightweighting structures, and body panels made out of aluminum and composites, SAE’s Acoustical Materials Committee is developing a new damping standard. This standard is also very suitable in determining the damping performance of materials used in the off-highway applications, where the thickness of the steel body panel is much greater than in the automotive application. The general methodology of this standard is based on the mechanical impedance measurement method and has been developed with the general consensus of automotive engineers, suppliers, and independent test laboratories. This method is essentially based on the fact that a bar is excited at the center by a shaker. The force exerted by the shaker and the corresponding vibration is measured at that point to determine the frequency response function of the mechanical impedance signal.
Technical Paper

Comparison of Emissions Measurement Methods based on Chassis Dynamometer Testing

2021-04-06
2021-01-0611
Engine and vehicle tailpipe emissions can be measured in laboratories equipped with engine dynamometers and chassis dynamometers, respectively. In addition to laboratory testing, there is an increase in interest to measure on-road vehicle emissions using portable emissions measurement systems in order to determine real-driving emissions. Current methods to quantify engine, vehicle tailpipe, and real-driving emissions include the raw continuous, dilute continuous, and dilute bag measurement methods. Although the dilute bag measurement method is robust, recent improvements to the raw and dilute continuous measurement methods can account for the time delay between the probe tip and analyzer in addition to gas transport dynamics in order to reliably recover the tailpipe concentration signals. These improvements significantly increase the reliability of results using the raw and dilute continuous measurement methods, making them possible alternatives to the bag method.
Technical Paper

Sound Quality Evaluation Method for Engine Combustion Noise in an Engine Acoustic Test Cell

2021-04-06
2021-01-0674
In order to efficiently enhance engine sound quality under acceleration, the authors have developed an evaluation method for primary judgment of the sound quality of engine combustion noise at the stage of advanced engine development before the prototype vehicle is built. This method is an application of an existing method for evaluating the sound quality of engine combustion noise in vehicle interiors to the evaluation of noise and vibration at an engine acoustic test bench. In this method, it is necessary to consider the air-borne and the structure-borne components separately. The analysis procedure for the air-borne component is as follows. First, the sound pressure at a point 1 m away from the engine and the in-cylinder pressure of each cylinder are measured simultaneously in a semi-anechoic engine dynamometer test chamber. Next, the signal correlated with engine combustion is extracted from the measured sound pressure using the time domain combustion noise separation method.
Technical Paper

Application of DFSS Taguchi Method to Design Robust Shock Tower

2021-04-06
2021-01-0234
Design for Six Sigma (DFSS) is an essential tool and methodology for innovation projects to improve the product design/process and performance. This paper aims to present an application of the DFSS Taguchi Method for an automotive/vehicle component. High-Pressure Vacuum Assist Die Casting (HPVADC) technology is used to make Cast Aluminum Front Shock Tower. During the vehicle life, Shock Tower transfers the road high impact loads from the shock absorber to the body structure. Proving Ground (PG) and washout loads are often used to assess part strength, durability life and robustness. The initial design was not meeting the strength requirement for abusive washout loads. The project identified eight parameters (control factors) to study and to optimize the initial design. Simulation results confirmed that all eight selected control factors affect the part design and could be used to improve the Shock Tower's strength and performance.
Technical Paper

Direct Yaw Control Based on Optimal Longitudinal Tire Forces for 8×8 Combat Vehicle

2021-04-06
2021-01-0261
This paper proposes an active chassis control strategy for an Eight-wheel drive/Four-wheel steering (8WD/4WS) combat vehicle, where only the first and second axles’ wheels are steerable, while the third and fourth axles’ wheels are non-steerable. Utilizing torque vectoring and differential braking control to improve its lateral dynamics at limit handling. Due to the non-linear characteristics of the tires and its friction limit, the vehicle may exhibit instable behavior during cornering maneuvers. It is well known that the tire longitudinal and lateral forces are shared, if longitudinal forces increased, slip ratio will increase and causing reduction in lateral forces that may cause the vehicle to drift out or spinning. Accordingly, the tires forces need to be optimally distributed based on vertical loads for each tire to prevent it from reaching the friction limit based on Friction Ellipse Theorem.
Technical Paper

Implementation and Validation of Behavior Cloning Using Scaled Vehicles

2021-04-06
2021-01-0248
Recent trends in autonomy have emphasized end-to-end deep-learning-based methods that have shown a lot of promise in overcoming the requirements and limitations of feature-engineering. However, while promising, the black-box nature of deep-learning frameworks now exacerbates the need for testing with end-to-end deployments. Further, as exemplars of systems-of-systems, autonomous vehicles (AVs) engender numerous interconnected component-, subsystem and system-level interactions. The ensuing complexity creates challenges for verification and validation at the various component, subsystem- and system-levels as well as end-to-end testing. While simulation-based testing is one promising avenue, oftentimes the lack of adequate fidelity of AV and environmental modeling limits the generalizability. In contrast, full-scale AV testing presents the usual limitations of time-, space-, and cost.
Technical Paper

Cast Magnesium Subframe Development-Corrosion Mitigation Strategy and Testing

2021-04-06
2021-01-0279
A cast magnesium AE44 subframe was designed and manufactured for a C Class sedan to reduce weight and improve vehicle fuel economy. Corrosion mitigation strategies were developed to reduce the likelihood of galvanic corrosion. Both a proving ground vehicle corrosion test and a laboratory component corrosion test were conducted. The vehicle test result demonstrated that the corrosion mitigation strategies were effective. They also provided lessons learned on clearance between magnesium and steel components and options to improve the subframe’s corrosion resistance. The magnesium subframe achieved 5 kg (32%) weight reduction from the equivalent steel subframe and met all the required structural performance targets.
Technical Paper

Assessment of Novel V2X Applications Using a Simulation Platform

2021-04-06
2021-01-0115
Vehicle to Everything (V2X) technology has been studied extensively in the past years. Limited pilot and production deployments, and research work have demonstrated V2X benefits. These include improvement to safety, mobility conditions and environmental benefits. Several safety and mobility applications have been investigated in literature. Nonetheless, V2X holds a potential for broader innovation in connected and automated vehicle applications. Feasibility assessment and algorithm validation of such applications may prove to be challenging. This results from costs associated with test track rental and equipping vehicles with V2X technology. Besides, limited V2X penetration rate leads to unavailability of naturalistic testing environment. In this paper, we investigate the use of the autonomous vehicle simulation, named Carla, for V2X application validation. Carla is an open source project that we altered to enable V2X applications assessment.
X