Criteria

Display:

Results

Viewing 1 to 30 of 4021
2015-01-14
Technical Paper
2015-26-0125
Sambhaji Keshaw Jaybhay, Sudhakara Naidu, Prasanna Nagarhalli, J Saiprasad
LCV AC buses market is rapidly growing up in India; major requirement is for staff pick-up and drop, school applications and private fleet owners. The air-conditioning system is typically mounted on bus roof top and located laterally and longitudinally at center. It is an easiest and most feasible way to package air conditioning system to cater the large passenger space (32 to 40seats) with the conditioned air. This makes air conditioning duct design simple and commercially viable. Most of the LCV buses are with front engine configuration which adds more heat and noise to Driver and passenger compartment, this demands for isolation of Driver’s area from passenger area by means of partition in between. Without partition engine noise is more dominant in passenger area, but in case of with partition, blower noise of roof mounted AC system is more perceivable in passenger area.
2015-01-14
Technical Paper
2015-26-0127
Gaurav Paliwal, Naveen Sukumar, Umashanker Gupta, Saurav Roy, Hemantkumar Rathi
The main emphasis for a Commercial vehicle design which was focused on fuel-economy and durability does not fulfill the increasing customer expectations anymore. Commercial vehicle designers need to focus on other vehicle aspects such as steering, ride comfort, NVH, braking, ergonomics and aesthetics in order to provide car like perception to truck, bus drivers and passengers during long distance drives. Powertrain mounting system must perform many functions. First and foremost, the mounting system must maintain & control the overall motion of the powertrain, to restrict its envelope reasonably, thereby avoiding damage to any vehicle component from the potential impact. This requires the mount to be stiff. Second the mount must provide good vibration isolation to have a comfortable ride to the vehicle occupant. This requires the mount to be soft.
2015-01-14
Technical Paper
2015-26-0130
Pradeep Kumar Singh
Gear noise and vibration in automobile transmissions is a phenomenon of great concern. Noise generated at the gearbox, due to gear meshing, also known as gear whine, gets transferred from the engine cabin to the passenger cabin via various transfer paths and is perceived as air borne noise to the passengers in the vehicle. This noise due to its tonal nature can be very uncomfortable to the passengers. Optimizing micro-geometry of a gear pair can help in improving the stress distribution on tooth flank and reducing the sound level of the tonal noise generated during the running of the gearbox when that gear pair is engaged. This technical paper contains the study of variation in noise level in passenger cabin and contact on tooth flank with change in micro-geometry parameters (involute slope and lead slope) of a particular gear pair. Further scope of study has been discussed at the end of the paper.
2015-01-14
Technical Paper
2015-26-0122
Herman Van der Auweraer, Karl Janssens, Fabio Bianciardi, Filip Deblauwe, Kumaraswamy Shivashankaraiah
Certification of vehicle noise emissions for passenger vehicles, motorcycles and light trucks is achieved by measuring external sound levels according to procedures defined by international standards such as ISO362. The current procedure based on a pass-by test during wide-open throttle acceleration is believed to be far from actual urban traffic conditions. Hence a new standard pass-by noise certification is the new ISO 362:2007 is being evaluated for implementation that puts testing departments through their paces with requirements for additional testing under multiple ‘real world’ conditions. The new ISO standard, together with the fact that most governments are imposing lower noise emission levels, makes that most of the current models don’t meet the new levels which will be imposed in the future. Therefore automotive manufacturers are looking for new tools which are giving them a better insight in the Pass-by Noise contributors.
2015-01-14
Technical Paper
2015-26-0124
Vilas Deoolkar
Pass – by testing is increasingly done In-door in a hemi-anechoic environment. Advantages of this method are high repeatability and independence of weather conditions. Often rooms smaller than the standardized size will provide accurate results. Product optimisation work often requires information about the noise contribution from the different vehicle noise sources. In this presentation different room sizes are discussed and an accurate time - based contribution analysis method is explained and documented with results from a practical example. Time domain has a number of advantages. The calculations are simple and hence the data are available for processing in other domains. It is possible to directly listen to the individual component contributions when working on exterior brand sound.
2015-01-14
Technical Paper
2015-26-0123
Yogesh Surkutwar, Mahesh Anand Patwardhan, Nagesh Voderahobli Karanth, Atul Gaikwad
Use of Combined CAE and Experimental Testing Approach for Engine Noise Reduction Y. V. Surkutwar, A. A. Gaikwad, M.A. Patwardhan, N.V. Karanth, ARAI Pune Abstract The work presented in this paper deals with the use of combined CAE and experimental testing approach for reducing engine noise. The paper describes a systematic approach for giving solutions to structure borne engine noise related problems. Noise Source Identification (NSI) was carried out on diesel engine to identify noise radiating sources, ranking of noise sources was carried out and contribution of individual engine component in radiated Sound Level (SWL) was computed. Detailed Finite Element model of Engine assembly was developed and model was correlated in terms of natural frequencies and transfer functions by performing modal testing. Correlated FE model was used for predicting surface vibration velocities under various engine speeds and loading conditions in frequency domain.
2015-01-14
Technical Paper
2015-26-0134
Jayant Sinha, Ajit Kharade, Shrihari Matsagar
An interior sound quality is one of the major performance attribute, as consumer envisage this as class and luxury of the vehicle. With increasing demand of quietness inside the cabin, car manufactures started focusing on noise refinement and source separation. This demand enforces hydraulic power steering pump to reduce noise like Moan and Whine, especially in silent gasoline engine. To meet these requirements, extensive testing and in-depth analysis of noise data is performed. Structured process is established to isolate noises and feasible solutions are provided considering following analysis. a) Overall airborne noise measurement at driver ear level (DEL) inside the cabin using vehicle interior microphone. b) Airborne and Pressure pulsation test by sweeping pump speed and pressure at test bench. c) Waterfall analysis of pump at hemi anechoic chamber for order tracking and noise determination.
2015-01-14
Technical Paper
2015-26-0135
Kalpesh Mistry, Steve Fisher, Nitin Badhe
Vehicle level Acoustic sound pack sensitivity and Test correlation by utilising Statistical Energy Analysis (SEA) technique for Premium SUV Kalpesh A. Mistry, Atul D. Pol, Ajay Virmalwar Tata Technologies Ltd., Pune, India Steve Fisher Jaguar Land Rover Ltd., Gaydon, UK SAE SIAT at India,2015 Abstract Due to increased awareness by customer perceived sound characteristics, advance simulation technique emerged in NVH domain for mid-high frequency like BEM, Hybrid and Statistical Energy Analysis (SEA). Structure-borne noise simulation primarily relies on the finite element (FE) technique and due to wide knowledge base, it is in position to get correlated results and prediction. One of the most widely and accepted practice is SEA to assess and optimize Acoustic sound pack for Air Borne Noise (ABN) in the range of 400 Hz to 10,000 Hz typically for Powertrain and Tyre Patch Noise Reduction. As Prof.
2015-01-14
Technical Paper
2015-26-0141
Ravishastri Gadasu, Anshul Khatri, Aashish Parmar
With increase in product diversity in passenger car market, the need for NVH comfort has gained very strong foothold in every segment. This needs in depth analysis for limiting the noise at part level. Radiator Fan Module is one of such part which contributes to Cabin comfort in major way. In this paper, author is focusing on designing of RFM in order to have low noise. Primary objective of RFM is to meet Heat rejection requirement with optimized air flow. Radiator Fan is primarily responsible for meeting air flow requirement within specified noise limit. For flow inducing components like Radiator Fan, there is always a trade-off between the functional requirement and the noise from various sources (Electrical / Mechanical / Flow). Design of Fan blades and Motor Support ribs in RFM is critical to improve Flow noise, i.e. Air cutting noise.
2015-01-14
Technical Paper
2015-26-0139
Pradeep Kumar Singh
Noise generated in the driveline is mainly transferred inside the passenger cabin through air (air borne noise) and through the vehicle body structure, engine mounts, cables etc. Source of the noise generation in the vehicle is mainly through the engine fluctuation (engine combustion excitations). Any change in the engine characteristics results in the change in passenger cabin noise. Also, influence of the vehicle body structure due to change in material properties also affects the NVH performance. This technical paper explains the effect of change in engine characteristics as well as change in the transfer path due to design change on the NVH performance of the gear box and subsequently the NVH performance of vehicle.
2015-01-14
Journal Article
2015-26-0131
Abhishek Verma, M. L. Munjal
In this work, the noise attenuation characteristics of a three-chamber U-bend hybrid muffler have been investigated. Acoustic performance is quantified by the Transmission Loss (TL) parameter. One-dimensional transfer matrix based muffler program (TMMP) and three-dimensional finite element method (FEM) have been used for the prediction of the TL of the muffler. Presence of perforated baffles in geometry necessitates use of the Integrated Transfer Matrix (ITM) approach for the one-dimensional analysis because the sound fields in the elements would be coupled with each other, and for the 3D FEM analysis LMS Virtual Lab software has been used. The mean flow distribution in each of these configurations has been evaluated by means of a lumped flow resistance network. The resulting values of the grazing flow and bias flow have been used in the expressions for acoustic impedance of the perforates.
2015-01-14
Journal Article
2015-26-0136
Deepak Mahajan, Arnab Sandilya, Lokesh Khandelwal, Sameer Srivastava
Automotive floor carpet serves the purpose of insulating air borne noises like road/tire noise, transmission noise and fuel pump noise etc. Most commonly used automotive floor carpet structure is - Molded sound barrier (PE or vinyl etc) decoupled from floor pan with an absorber such as felt. With increasing customer expectations and fuel efficiency requirements, the NVH requirements are increasing as well. The only possible way of increasing acoustic performance (Specifically Sound Transmission Loss, STL) in the mentioned carpet structure is to increase the Barrier material. This solution, however, comes at a great weight penalty. Theoretically, increasing the number of decoupled barriers layers greatly enhances the STL performance of an acoustic packaging for same weight. However, practically this solution presents problems like- ineffectiveness at lower frequencies, sudden dip in performance at modal frequencies.
2014-11-11
Technical Paper
2014-32-0020
Patrick Falk, Christian Hubmann
Abstract Originally developed for the automotive market, a fully automatic real-time measurement tool AVL-DRIVE is commercially available for analyzing and scoring vehicle drive quality, also known as “Driveability”. This system from AVL uses its own transducers, calibrated to the sensitivity and response of the human body to measure the forces felt by the driver, such as acceleration, shock, surging, vibration, noise, etc. Simultaneously, the vehicle operating conditions are measured, (throttle grip angle, engine speed, gear, vehicle speed, temperature, etc.). Because the software is pre-programmed with the scores from a multitude of different vehicles in each vehicle class via neural networks and fuzzy logic formula, a quality score with reference to similar competitor vehicles is instantly given. This tool is already successfully implemented in the market for years to investigate such driveability parameters for passenger cars.
2014-11-11
Technical Paper
2014-32-0025
Maki Kawakoshi, Takashi Kobayashi, Makoto Hasegawa
Abstract ISO26262 was intended only for passenger cars but can be applied to motorcycles if the Controllability (C) is subjectively evaluated by expert riders. Expert riders evaluate motorcycle performance from the viewpoint of ordinary riders. However, riding maneuvers of ordinary riders have not been confirmed by objective data. For this reason, it is important to understand the basic characteristics of riding maneuvers of both expert and ordinary riders. This study seeks to confirm the compatibility between the riding maneuvers of expert riders and those of ordinary riders. The riding maneuvers and vehicle behavior of four expert riders and 16 ordinary riders were compared using the results of a test assuming normal running.
2014-10-13
Technical Paper
2014-01-2896
Krzysztof Jan Siczek
Abstract Conditions of the bacterial battery have been presented in the article. The models of different design configurations of bacterial battery and its assembly with electric circuit has been elaborated. The obtained values of voltage and currents obtained in such models has been compared with the case of similar circuit using lithium-ion battery and presented in the paper.
2014-10-13
Journal Article
2014-01-2869
Harald Stoffels, Kay Hohenboeken
Abstract The impact of the number of cylinders on two downsized gasoline engines on driving habits in the same passenger-vehicle type was investigated. This was carried out with two similar vehicles, equipped with an in-line three cylinder (i3) and an in-line four cylinder (i4) engine, both having same power, torque and transient-response behaviour. Both engine types were mated to six-speed manual transmissions with same gear-ratios and dual-mass flywheel characteristics. The study was performed by letting a statistically significant number of subjects driving the same route and both vehicles consecutively. The relevant data during driving were recorded simultaneously from either vehicle integrated sensors (CAN), and secondary transducers.
2014-09-30
Technical Paper
2014-01-2398
Sanket Pawar
Abstract Off-road commercial vehicles many times have to work at remote areas in poor working conditions like reduced visibility due to fog, snow, inadequate ambient lighting, dust etc. They may not have any access to emergency facilities in such places. Challenging geographical terrains and adverse weather conditions makes the situation worse. The combination of both can further degrade working conditions. The operator may need to either work or guide his vehicle through tight places or in hilly areas having such conditions. That imposes many challenges to operator in terms of efficiency & safety of both operator & vehicle. In an effort to increase productivity and efficiency operator may miss to look at safety aspects consequently, leading to accidents that can incur heavy losses due to damages to vehicle further delaying the work. It can even lead to a life threatening emergency in some cases.
2014-09-30
Technical Paper
2014-01-2424
Vignesh T. Shekar, Sreedhar Reddy
Abstract Bus and coach drivers spend considerably more time in the vehicle, compared to an average personal car user. However, when it comes to comfort levels, the personal cars, even the inexpensive hatchbacks score much higher than a standard bus. This is because the amount of ergonomic design considerations that go into designing a car's DWS (driver workspace) is much more than that of buses. To understand this lacuna, the existing standards and recommendations pertaining directly or remotely to bus driver workspace were studied. It was understood, beyond certain elementary recommendations, there were very few standards available exclusively for buses. This paper ventures to establish a set of guidelines, exclusively for designing bus and coach driver workspace. The various systems in the driver's work space and their relevance to driver's ergonomics are discussed. References are drawn from different case studies and standards to come up with recommendations and guidelines.
2014-09-30
Technical Paper
2014-01-2389
Quon Kwan, Leverson Boodlal
In this particular field study, the authors have demonstrated that telematics can be used to monitor and improve safe and fuel-efficient driving behavior. Telematics was used to monitor various driver performance parameters: unsafe events (sudden accelerations and hard braking expressed as Yellow and Red events, depending on severity), speeding, engine revolutions per minute (RPM), and fuel economy (miles per gallon). The drivers consisted of two groups: drivers of day cabs and drivers of sleeper cabs. The drivers of both groups were monitored during a baseline period during which no feedback, coaching, or rewards were provided. Then, the drivers of both groups were monitored during an intervention period, during which drivers were provided with feedback, coaching, and rewards.
2014-09-30
Technical Paper
2014-01-2383
Takahiko Yoshino, Hiromichi Nozaki
Abstract In recent years, the conversion of vehicles to electric power has been accelerating, and if a full conversion to electric power is achieved, further advancements in vehicle kinematic control technology are expected. Therefore, it is thought that kinematic performance in the critical cornering range could be further improved by significantly controlling not only the steering angle but also the camber angle of the tires through the use of electromagnetic actuators. This research focused on a method of ground negative camber angle control that is proportional to the steering angle as a technique to improve maneuverability and stability to support the new era of electric vehicles, and the effectiveness thereof was clarified. As a result, it was found that in the critical cornering range as well, camber angle control can control both the yaw moment and lateral acceleration at the turning limit.
2014-09-30
Journal Article
2014-01-2380
Joshua L. Every, M. Kamel Salaani, Frank S. Barickman, Devin H. Elsasser, Dennis A. Guenther, Gary J. Heydinger, Sughosh J. Rao
Dynamic Brake Support (DBS) is a safety system that has been applied to various passenger cars and has been shown to be effective at assisting drivers in avoiding or mitigating rear-end collisions. The objective of a DBS system is to ensure that the brake system is applied quickly and at sufficient pressure when a driver responds to a collision imminent situation. DBS is capable of improving braking response due to a passenger car driver's tendency to utilize multi-stage braking. Interest is developing in using DBS on commercial vehicles. In order to evaluate the possible improvement in safety that could be realized through the use of DBS, driver braking behavior must first be analyzed to confirm that improvement is possible and necessary. To determine if this is the case, a study of the response of truck drivers' braking behavior in collision imminent situations is conducted. This paper presents the method of evaluation and results.
2014-09-30
Technical Paper
2014-01-2405
Jiaqi Xu, Bradley Thompson, Hwan-Sik Yoon
Abstract Hydraulic excavators perform numerous tasks in the construction and mining industry. Although ground grading is a common task, proper grading cannot easily be achieved. Grading requires an experienced operator to control the boom, arm, and bucket cylinders in a rapid and coordinated manner. Due to this reason, automated grade control is being considered as an effective alternative to conventional human-operated ground grading. In this paper, a path-planning method based on a 2D kinematic model and inverse kinematics is used to determine the desired trajectory of an excavator's boom, arm, and bucket cylinders. Then, the developed path planning method and PI control algorithms for the three cylinders are verified by a simple excavator model developed in Simulink®. The simulation results show that the automated grade control algorithm can grade level or with reduced operation time and error.
2014-09-28
Journal Article
2014-01-2499
Lijun Zhang, Cheng Ruan, Dejian Meng
Abstract Brake pedal feel characteristic is determined by the structural and kinetic parameters of the components of the brake system. As the servo power component of the brake system, vacuum booster has a significant influence on the brake pedal feel. In this paper, a brake system model for brake pedal feel which has a detail vacuum booster mathematical description is established in the software MATLAB/Simulink. The structure gaps, spring preload, friction force and reaction disc characteristics of vacuum booster are considered in this model. A brake pedal feel bench test under different input velocity and vacuum pressure is completed in order to validate the prediction of the model.
2014-09-16
Journal Article
2014-01-2266
Helen Lockett, Sarah Fletcher, Nicolas Luquet
Abstract The installation of essential systems into aircraft wings involves numerous labour-intensive processes. Many human operators are required to perform complex manual tasks over long periods of time in very challenging physical positions due to the limited access and confined space. This level of human activity in poor ergonomic conditions directly impacts on speed and quality of production but also, in the longer term, can cause costly human resource problems from operators' cumulative development of musculoskeletal injuries. These problems are exacerbated in areas of the wing which house multiple systems components because the volume of manual work and number of operators is higher but the available space is reduced. To improve the efficiency of manual work processes which cannot yet be automated we therefore need to consider how we might redesign systems installations in the enclosed wing environment to better enable operator access and reduce production time.
2014-05-09
Journal Article
2014-01-9127
Kazumoto Morita, Michiaki Sekine
The number of elderly drivers is increasing in Japan and ensuring the safety of elderly drivers is becoming an important issue. The authors previously conducted an analysis of the characteristics of accidents and traffic violations by elderly drivers based on the number of accidents in which they were rear-ended. This method was used in order to exclude the influence of driving frequency. As a result of that analysis, it was found that the likelihood of violations committed by elderly drivers was not particularly higher than in other age groups, while the likelihood of accidents caused by them was higher. The risk of causing an accident was judged to be about two times higher in elderly drivers than in the 35-44 year age group. However, the methodology presupposed that collisions in which a driver is rear-ended are accidents that occur randomly, and that they occur with the same probability in each age group.
2014-05-09
Journal Article
2014-01-9126
Nikolina Samardzic
Values of the speech intelligibility index (SII) were found to be different for the same speech intelligibility performance measured in an acoustic perception jury test with 35 human subjects and different background noise spectra. Using a novel method for in-vehicle speech intelligibility evaluation, the human subjects were tested using the hearing-in-noise-test (HINT) in a simulated driving environment. A variety of driving and listening conditions were used to obtain 50% speech intelligibility score at the sentence Speech Reception Threshold (sSRT). In previous studies, the band importance function for ‘average speech’ was used for SII calculations since the band importance function for the HINT is unavailable in the SII ANSI S3.5-1997 standard.
2014-04-01
Technical Paper
2014-01-0078
Rama Subbu, Baskar Anthony Samy, Piyush mani Sharma
Abstract Fierce competition in India's motorcycle industry has led to constant product innovation among manufacturers. This has resulted in the reduction of the lifecycle of the vehicle and has driven the manufacturers to alter the product design philosophies and design tools. One of the performance factors that have continued to challenge motorcycle designers is ride comfort in vertical and longitudinal direction. An essential tool in the motorcycle development process is the ability to quantify and grade the ride comfort behavior. This is performed either through subjective or objective tests. Subjective tests have the disadvantage that numerous factors influence test drivers' opinion while objective measures have the advantage of repeatability.
2014-04-01
Technical Paper
2014-01-0875
Mark William Arndt
Abstract The current certification requirements under CFR 49, Part 567 state that GVWR of a motor vehicle shall not be less than the sum of the unloaded vehicle weight, rated cargo weight and 150 pounds times the number of designated seating positions. Actual occupant weight distributions versus certified weight per occupant seat causes a potential conflict between a vehicle's in-use weights versus its certified GVWR. Population weight distributions were developed based upon The Center for Disease Control's (CDC) publication of 2007 - 2010 anthropometric reference data and publically available weights of a special population from high school football teams. For five buses from small (18-seat) to large (55-seat), key parameters were measured.
2014-04-01
Technical Paper
2014-01-0892
Eric Frank, Peter Jacobsen
Abstract As the demand for Sound Quality improvements in vehicles continues to grow, robust analysis methods must be established to clearly represent end-user perception. For vehicle sounds which are tonal by nature, such as transmission or axle whine, the common practice of many vehicle manufacturers and suppliers is to subjectively rate the performance of a given part for acceptance on a scale of one to ten. The polar opposite of this is to measure data and use the peak of the fundamental or harmonic orders as an objective assessment. Both of these quantifications are problematic in that the former is purely subjective and the latter does not account for the presence of masking noise which has a profound impact on a driver's assessment of such noises. This paper presents the methodology and results of a study in which tonal noises in the presence of various level of masking noise were presented to a group of jurors in a controlled environment.
2014-04-01
Technical Paper
2014-01-0881
Mitsuru Enomoto, Michiko Kakinuma, Nobuhito Kato, Haruo Ishikawa, Yuichiro Hirose
Abstract Design work for truck suspension systems requires multi-objective optimization using a large number of parameters that cannot be solved in a simple way. This paper proposes a process-based systematization concept for ride comfort design using a set-based design method. A truck was modeled with a minimum of 13 degrees of freedom, and suspension performance under various vehicle speeds, road surface conditions, and load amounts was calculated. The range of design parameters for the suspension, the range of performance requirements, and the optimal values within these ranges were defined based on the knowledge and know-how of experienced design engineers. The final design of the suspension was installed in a prototype truck and evaluated. The performance of the truck satisfied all the objectives and the effectiveness of the set-based design approach was confirmed.
Viewing 1 to 30 of 4021