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Viewing 1 to 30 of 227
2013-05-13
Technical Paper
2013-01-2008
Steven Jorro, John Zehme, Sam Mleczko, Eglind Myftiu, Blake Rager
The reduction of full acceleration truck pass-by noise conforming to Type ECE-51 regulation (Reference 1) was predicted in a hemi-anechoic chassis dynamometer chamber with microphone arrays and compared with actual test track results. This gave a close match to the track data, with both showing a 4 dB reduction in the A-weighted overall noise level after identical acoustic treatments were applied. Noise control materials were selected to perform as acoustic barriers and absorbers. These were optimized by analyzing the 1/3 octave spectra, determining dominant frequency bands, in critical source locations and engine speeds, and using combinations that dissipate or contain energy well within those bands. With the truck being stationary while tested, important source locations could be quickly identified both subjectively and with localization tools such as Beamforming.
2013-09-24
Journal Article
2013-01-2379
Zhigang Wei, Shengbin Lin, Limin Luo, Fulun Yang, Dmitri Konson, Bala Gurusamy
Durability/reliability design of products, such as auto exhaust systems, is essentially based on the observation of test data and the accurate interpretation of these data. Therefore, test planning and related data analysis are critical to successful engineering designs. To facilitate engineering applications, testing and data analysis methods have been standardized over the last decades by several standard bodies such as the American Society for Testing and Materials (ASTM). However, over the last few years, several effective testing and data analysis methods have been developed, and the existing standard procedures need to be updated to incorporate the new observations, knowledge, and consensus. In this paper, the common practices and the standard test planning and data analysis procedures are reviewed first. Subsequently, the recent development in accelerated testing, equilibrium based data fitting, design curve construction, and Bayesian statistical data analysis is presented.
2013-09-24
Technical Paper
2013-01-2377
Sivashankar S, Sudarsanam S, N. Saravanan
Based on customer application and loading condition, each Commercial Vehicle model has an entirely different usage pattern. To perform accurate durability validation, each vehicle model prototype should run on actual customer usage locations and loading conditions for the durability target kilometers. But it is time consuming and not practical. So a statistical approach is followed to generate the accelerated durability test sequence and target on in-house Proving Ground tracks to match the real customer usage for the durability target kilometers. Again a single durability test sequence and target cannot be followed for all vehicle models due to the variability in customer usage. For that, specific durability test sequence and target need to be established for every class of commercial vehicle. This paper summarizes the methodology to develop Durability test sequence and target for commercial vehicle based on the work carried out on variants of medium and heavy duty trucks.
2013-09-24
Technical Paper
2013-01-2356
Boris Beloousov, Tatiana I. Ksenevich, Vladimir Vantsevich, Dmitry Komissarov
Two characteristics of terrain mobility are essential in designing an unmanned ground vehicle (UGV): (i) the ability of a vehicle to move through terrain of a given trafficability and (ii) the obstacle performance, i.e., the ability to avoid, interact with and overcome obstacles encountered on a preset route of a vehicle. More attention has been given to the vehicle geometry including selection of the angles of approach and departure, radii of longitudinal and lateral terrain mobility, and the steering system configuration. An essential effect is exhibited by the tire properties in their interaction with the support surface; this, in turn, affects traction properties of the wheel and, thus, vehicle terrain mobility. However, the influence of power distribution between the driving wheels together with vehicle steering system on the two above-listed characteristics of terrain mobility has not been considered in depth.
2004-10-26
Technical Paper
2004-01-2679
Richard L. Wurst
This paper describes equipment developed to measure engine output torque. Several vehicle flexplates were modified and strain gauges were applied to measure torque. Special attention was paid to minimize or eliminate any changes in flexplate torsional stiffness. Torque signals are transmitted from the rotating flexplate to a stationary receiver via RF telemetry. The electronics on the rotating flexplate are powered using an induction power technique. This method was developed as a less invasive and less costly alternative to strain gauging a crankshaft.
2004-10-26
Technical Paper
2004-01-2733
William P. Fornof
A coalescing filter is typically used in a compressed air system to remove liquid and oil aerosols. A coalescing filter is most efficient when located downstream of an air dryer. The air dryer removes most of the liquid oil condensed in the compressor discharge line. Measuring the percent of oil removed by a coalescing filter is useful for determining efficiency. This paper covers a laboratory method to reproduce oil aerosols much like the filter will see in an actual application. High duty cycles produce the maximum amount of oil from the compressor. The air dryer acts as pre-filter for the coalescing filter. The coalescing filter element and its associated housing should be tested as a unit since the element's inherent efficiency is effected by the design of the housing.
2004-11-16
Technical Paper
2004-01-3437
Paulo Pedro Kenedi, Leydervan de Souza Xavier, Ricardo A. Amar de Aguiar, Rafael de Oliveira Sampaio, Thiago Fontes Carvalho de Queiroz
In order to resist impact loadings that usually occurs in an off-road circuit an integrated approach of mechanical design is developed to obtain an optimized vehicle suspension. Efforts were made to model a front suspension, type double A of an off-road vehicle Mini-Baja. The focus was stressed in the transmissibility of mechanical forces through front suspension. A simple analytic model was done to esteem the reactions generated at points of linkage of suspension and structure of Mini-Baja, during a transient impact load. Numerical simulation softwares were also used to visualize dynamic behavior of different front suspension configurations. Finally experimental test was done with data acquisition system, with the use of load cells, to generate a reference data to compare analytic and numerical models.
2013-01-09
Technical Paper
2013-26-0038
S. R. Nigade, S. S. Dandge, R. S. Mahajan, H. V. Vankudre
Automotive Industry Standard (AIS)-031 specifies the requirement of strength of large passenger vehicles in case of rollover. In India the certificate is granted after the successful completion of rollover test of the vehicle as per AIS-031. Complete vehicle is used for rollover test in which the vehicle is tilted laterally in the ditch of 800 mm. Such tests with complete vehicle are costly and unaffordable to small bus body builders. So according to Annex 2 of AIS-031, manufacture can carryout rollover on body sections of the vehicle. This is an equivalent approval method which is less costly compared to rollover test on complete vehicle. It requires detailed study of superstructure and selection of weakest body sections from the given superstructure of bus, which in turn requires mass and energy calculation of body section. For doing rollover analysis using body section, bus is selected which has already passed a full-rollover test.
2011-09-13
Technical Paper
2011-01-2291
Marius-Dorin Surcel, Jan Michaelsen, Yves Provencher
This project's objective was the development of an on-road vehicle fuel consumption test procedure for representative stop-and-go urban duty cycles. The scope of the project included a review of existing stop-and-go urban duty cycles, the development of a track testing methodology for measuring the fuel consumption on stop-and-go urban duty cycles, and testing with a view to the validation of the methodology. Literature review analyzed several transport activities to determine specific stop-and-go urban duty cycles, such as pick-up and delivery operations, refuse collection, bus transport, and utility and service operation. It was found that driving cycles should be easy enough to recreate and replicate on the test track and should be representative of application driving patterns. The cycles should be adapted for fuel economy testing, and geometric cycles are easier to follow than the cycles based on actual drive traces.
2011-09-13
Technical Paper
2011-01-2292
Tianlei Zheng, Yuefu Jin, Zhao Wang, Michael Wang, Freda Fung, Fatumata Kamakate, Huiming Gong
To restrain the environmental and energy problems caused by oil consumption and improve fuel economy of heavy-duty commercial vehicles, China started developing relevant standards from 2008. This paper introduces the background and development of China's national standard “Fuel consumption test methods for heavy-duty commercial vehicles”, and mainly describes the test method schemes, driving cycle and weighting factors for calculating average fuel consumption of various vehicle categories. The standard applies to heavy-duty vehicles with the maximum design gross mass greater than 3500 kg, including semi-trailer tractors, common trucks, dump trucks, city buses and common buses. The standard adopts the C-WTVC driving cycle which is adjusted on the basis of the World Transient Vehicle Cycle[1, 2] and specifies weighting factors of urban, rural and motorway segments for different vehicle categories.
2010-10-17
Technical Paper
2010-36-0511
Andre Oliveira, Lucas Coser, Vinicius Porto
Methods for determining the acoustic absorption coefficient of materials are broadly known in NVH engineering and traditionally rely on measurements performed in specimens carefully prepared such as those used in the Kundt's tube. It is understood that the acoustic behavior of a material slice in a well-controlled test bench provides very different circumstances from those found when the material is used in its application location (in situ condition) mostly because of the structural interactions and the boundary conditions involved. Many questions arise when the goal is to understand which absorbing material will be more effective and, moreover, if its cost is worth enough to solve particular noise issues. To answer those questions, acoustic impedance determination using direct particle velocity measurements were used in this work, in which several absorbing coatings used in specific regions of Brazilian truck cabins were mapped and compared.
1999-11-15
Technical Paper
1999-01-3778
Thomas Spoerl, Charles Nesser
Electronic Control Unit (ECU) networks should be tested as a system to ensure efficient and accurate results. Often, testing of ECU networks is performed with specially equipped test vehicles. In–vehicle testing is particularly costly, time–consuming, and inefficient with heavy–duty trucks. Also, complete code coverage is typically not achieved with in–vehicle testing. This incomplete testing can lead to numerous problems including an increase in warranty costs and the failure to meet regulatory requirements. A scalable Hardware–in–the–Loop (HiL) system can provide a means to test such large ECU networks in a laboratory environment.
1999-11-15
Technical Paper
1999-01-3782
Craig V. Robertson, Philip J. Smith, Roland L. Ruhl
This paper describes a practical and efficient approach for determining complete transient, as well as steady state response of tractor-trailer air brake systems by recording pushrod displacement and air brake service line pressure as a function to time. The test hardware utilizes easy to fabricate “clip on” transducers to measure pushrod stroke length. Data acquisition is via LABVIEW‚. All transducers are easy to temporarily affix to any tractor- trailer and require no alteration to the vehicle. A complete system check takes less time than manually measuring pushrod stroke as required under FMCSA. This system with one treadle application and release gives digital timing and displacement history of all brakes. Useful information includes: application and release profiles (pushrod velocity), shoe compliance upon seating and crack pressure release points for both tractor and trailer relay valves.
1999-11-15
Technical Paper
1999-01-3762
Ronald W. Friend, Timothy J. Frashure
An analysis of salt water effects and test methods to design Antilock Brake System (ABS) Electronic Control Units (ECUs) capable of withstanding the Heavy Vehicle frame mount environment. An examination of new and existing test methods and design techniques to ensure reliability over the life of the vehicle.
2011-01-19
Technical Paper
2011-26-0092
Vikas Yadav, Gerardo Olivares
Public transportation system and specifically transit bus systems are key element of the national transportation network in United States. Buses are one of the safest forms of transportation. Nonetheless, bus crashes resulting in operator injuries and fatalities do occur. According to National Transportation Statistics from 1990-2002, the number of transit motor buses in the U.S. has increased by 30% [1]. The majority of fatal crashes involving transit buses result from frontal crashes which could be fatal for bus operators. Therefore, crashworthiness research is a continuing effort. Research has been performed to analyze and improve the safety of transit bus operators. This paper describes the design, analysis and testing of an inflatable restraint system for a bus operator. At present a three point restraint is the only safety feature implemented on transit buses. The primary objective was to study the level of safety provided by the present safety system.
2004-11-16
Technical Paper
2004-01-3257
Ivan Roger Scansani Gregori
1. SUMMARY There is a large variation in the results of the durability of friction facings in field applications and in most cases there is very little information about the conditions in which the vehicle operated and therefore it was decided to developed a test procedure capable of containing all the different conditions of a vehicle. For this works statistical applications such as DOE (Experimental Design for Experiment) were used to help in planning and to obtain of equations of the tests results and Weibull curves for statistical analysis and comparison of failure mode. By this mean, it was possible to determine a correlation of the results on wear between the bench test and mileage covered on vehicle up to total wear. Therefore it is new possible to estimate the durability of friction facing on vehicles based on bench tests and also obtain knowledge about the behave of the material relative to energy and working temperature.
2013-04-08
Technical Paper
2013-01-0208
Jonas Brandt, Håkan Modin, Fredrik Rosen, Michael Försth, Raúl Ochoterena
This paper presents a recently developed method meant to act as a tool for objectively assessing and comparing the performance of automatic fire suppression systems. This methodology specifies requirements and procedures for evaluating the efficiency and performance of automatic fire suppression systems permanently installed in the engine compartments of buses and coaches. The testing is done according to SP method 4912 and carried out in a test enclosure where the fire performance of different suppression systems can be objectively assessed in a well-defined way. The test methodology includes a battery of fire tests simulating different engine loads, air flows and fire scenarios. Every tested system is rated according to its performance. The test method also includes testing of re-ignition due to hot surface ignition of liquid fuels.
2012-09-24
Technical Paper
2012-01-1975
Saud Binjuwair, Salah Ibrahim, Graham Wigley, Graham Pitcher
This paper deals with experimental investigations of the in-cylinder flow structures under steady state conditions utilizing Particle Image Velocimetry (PIV). The experiments have been conducted on an engine head of a pent-roof type (Lotus) for a number of fixed valve lifts and different inlet valve configurations at two pressure drops, 250mm and 635mm of H2O that correlate with engine speeds of 2500 and 4000 RPM respectively. From the two-dimensional in-cylinder flow measurements, a tumble flow analysis is carried out for six planes parallel to the cylinder axis. In addition, a swirl flow analysis is carried out for one horizontal plane perpendicular to the cylinder axis at half bore downstream from the cylinder head (44mm). The results show the advantage of using the planar technique (PIV) for investigating the complete flow structures developed inside the cylinder.
2012-09-24
Technical Paper
2012-01-1920
Seongil Lee, Eun Ho Roh
EPS has now become a compelling technology that nowadays rapidly replacing hydraulic power steering in world market because of its fuel efficiency, sophisticated assist control, additional safety and convenience features. There are various types of EPS such as Column assist type, Pinion assist type and Rack assist type. Small cars with less rack force are equipped with Column or Pinion assist type EPS but for full-sized vehicles with big rack power consumption need Rack assist EPS, what we call R-EPS. Each type of EPS has merits and demerits, but from the perspective of vehicle handling performance, R-EPS has some strong points. And this is why author started this study. Subjective handling evaluation has proven the superiority of R-EPS but objective evaluation was needed. So authors have tried to compare the on center handling characteristics of each EPS on the rig tests and proposed somewhat easy and reliable test method.
2012-09-24
Technical Paper
2012-01-1947
Jose J. Garcia
New emission regulations require innovation in the engine intake air loop. To satisfy these requirements, new architectures of cooling systems are in the process of development. These systems use valves to regulate the exhaust gas pressure and distribution in the intake cooling loop and ultimately combustion chambers. Since lower pressure is involved in the Exhaust Gas Recirculation (EGR), Water Charge Air Cooler (WCAC) or Air Charge Air Cooler (ACAC), the condensation of exhaust gas takes place and very acidic solutions are generated. In the absence of such new architecture of cooling system in service and in order to evaluate the corrosion risk that the acidic solutions from exhaust gases condensate could create in the EGR system, several tests have been proposed as representative for simulation of service conditions.
2016-09-27
Technical Paper
2016-01-8044
Guoyu Feng, Wenku Shi, Henghai Zhang, Qinghua Zu
Abstract In order to predict the fatigue life of thrust rod heavy duty commercial vehicle balanced suspension, based on the continuum mechanics theory, the fatigue life prediction model of rubber with equivalent effect as damage parameter is established. Based on the equivalent stress and fatigue cumulative damage theory, the fatigue damage evolution equation of rubber material expressed by stress is derived by using the strain energy function. The general fatigue life model is established by using the maximum logarithmic principal strain as the damage parameter. The finite element model of the thrust rod is established, and the stress distribution of the spherical hinge rubber layer and the easy damage area are analyzed. Based on the equivalent stress calculation results and the axial tension stress and strain data of the rubber material, the accuracy of the results of the finite element calculation is verified.
2016-09-27
Technical Paper
2016-01-8042
Danna Jiang, Ying Huang, Xiaoyi Song, Dechun Fu, Zhiquan Fu
Abstract This paper describes a uniform Hardware-In-the-Loop (HiL) test rig for the different types of Electronic Braking System (EBS). It is applied to both modular testing and integrated testing. This test rig includes a vehicle dynamic model, a real-time simulation platform, an actual brake circuit and the EBS system under test. Firstly, the vehicle dynamic model is a highly parameterized commercial vehicle model. So it can simulate different types of commercial vehicle by different parameter configurations. Secondly, multi-types of brake circuit are modeled using brake components simulation library. So, it can test the EBS control unit independently without the influence of any real electro-pneumatic components. And a software EBS controller is also modeled. So it can test the algorithm of EBS offline. Thirdly, all real electro-pneumatic components without real gas inputted are connected to the real-time test platform through independent program-controlled relay-switches.
2015-04-14
Technical Paper
2015-01-1015
Guanyu Zheng, Jianhua Zhang, Fengshuang Wang, Kaihua Zhao
Multiple suppliers have developed new cordierite 10.5″ OD substrates in China market. One key issue is to evaluate the feasibility of their applications to diesel SCR markets. To this end, test procedures were conceived and performed towards multiple substrate characteristics. Besides typical parameters such as product dimensions, structures, and material strength, thermo-mechanical properties were characterized by hot vibration, thermal shock and thermal cycle tests. Flow performance before and after tests was characterized by a hot flow bench. Four suppliers were selected to provide product samples which went through these developed rigorous test procedures. Comparisons of multiple properties were made. Conclusions regarding their applicability and recommendations for future work are provided at the end.
2015-09-01
Technical Paper
2015-01-1967
Takahito Niwa, Takashi Eguchi, Koichi Yamada, Satoshi Bunne, Toshihiko Omori, Takafumi Kato
With the diesel emissions and fuel consumption regulations and laws being tightened up, Common Rail System (CRS), capable of accurate and high-pressure diesel fuel injection, has become very popular in the world, and this CRS market is expected to continue to grow in the future. As use of the CRS becomes widespread, CRS is supposed to be used in a wide variety of environment, e.g. bad fuel (for example, much dust [1] and/or water), which increases concerns of CRS reliability. In an attempt to cope with such bad fuel properties, CRS and Fuel collected from the market was investigated. And based on this result, a new test method was worked out to simulate fuel stresses in the market. This test method verified the improved design of CRS with enhanced fuel robustness. This paper describes the new test method and the fuel robustness-enhancing effect of CRS based on the test method.
2014-05-07
Technical Paper
2014-36-0019
Eraldo de Jesus Soares, Alan M. Oliva, Camilo A. Adas, Fernando C. Dusi, Paulo Sergio P. Santos, Marco A. Fogaça Accurso, Marcus Kliewer
Abstract The purpose of this paper is to show a multiaxial bench test for static and dynamic testing of leaf springs for suspension of commercial vehicles. The bench test simulates the critical operating conditions (track, ramp, speed bump on track, curves and braking), with stroke control for strength and deformation analysis. One of the main advantages in bench test is to reduce the time of the test, its repeatability, its cost saving and monitoring its performance through inspections and graphic records. The aim of the test is to evaluate the behavior in durability of the components, to analyze the possible failure mode and to be able to approve or reject the component based on the test's results. Criteria were set to accelerate the test by comparing signals measured on the field and bench test with deflection by stress curves. These criteria were maintained under extreme conditions for longer than the observed in previous and real applications.
2014-09-30
Technical Paper
2014-36-0381
Daniel Mousinho Lago, Leonardo Chagas da Silva, Manoel Fernandes de Oliveira Filho, JoãoTelésforo Nóbrega de Medeiros
Abstract The internal combustion engines emit combustion gases which contain nano and micrometric particles that are harmful to human health, causing deleterious damages to the human's respiratory system. In Brazil, heavy vehicles, such as buses and trucks, have diesel engines that work under high loads and run through metropolitan areas or in intense traffic flow roads. They are considered, nowadays, the main solid particles emitter in several World's areas. There are already standard systems to analyze these particles quantitative and qualitatively at high prices collected from vehicle gases emissions in places such as bus stops. This paper presents a new method which retains solid micrometric particulate matter emitted by diesel engine. It is simple and has a relatively low cost. A sheet of textile element was encapsulated in a system for gripping micrometric particles emitted by diesel single-cylinder engine operating in a bench and coupled with a electrical generator.
2016-09-27
Technical Paper
2016-01-8083
Hans Christian Doering, Norbert Meyer, Markus Wiedemeier
Abstract Increasing diagnosis capabilities in modern engine electronic control units (ECUs), especially in the exhaust path, in terms of emission and engine aftertreatment control utilize on-board NOx prediction models. Nowadays it is an established approach at hardware-in-theloop (HIL) test benches to replicate the engine's steady-state NOx emissions on the basis of stationary engine data. However, this method might be unsuitable for internal ECU plausibility checks and ECU test conditions based on dynamic engine operations. Examples of proven methods for modeling the engine behavior in HIL system applications are so-called mean value engine models (MVEMs) and crank-angle-synchronous (in-cylinder) models. Of these two, only the in-cylinder model replicates the engine’s inner combustion process at each time step and can therefore be used for chemical-based emission simulation, because the formation of the relevant gas species is caused by the inner combustion states.
2017-03-28
Technical Paper
2017-01-0381
L. Karthik, R. Dinesh Kumar, E. Prasanna Kumar, V. Srinivasa Chandra
Abstract This abstract work describes a method of data acquisition and validation procedure followed for a metal bumper used in commercial vehicle application. Covariance is considered as major phenomenon for repeatable measurements in proving ground data acquisition and it is to be maintained less than 0.05. In this project covariance of data acquisition is analyzed before physical simulation of acquired data. In addition to that, multiple testing conditions like uni-axial and bi-axial testing were carried out to attain the failure. PG data is used for bi-axial vibration test and conventional constant spectrum signal (CSD signal) is used for uni-axial vibration test. Target duration for uni-axial test (Z direction) was arrived using pseudo damage calculation. Strain gauges were installed in failure locations to compare PG data and rig data as well as to calculate strain life. Failures were simulated in bi-axial vibration test.
2016-05-11
Technical Paper
2016-36-0067
Gustavo de Godoy José, Mauro Rebelatto, Rui Gustavo Lippert Schwanke, Telmo Roberto Strohaecker
Abstract This paper presents several tests carried out on a truck trailer on different types of pavement and load condition, using proving ground tracks and facilities, the instrumentation details, data analysis and validation. Through an extensive analysis of Brazilian goods road transport, a load vehicle combination and a list of test pavements were chosen as off-road pavement, highway pavement, pot holes, washboard, cobblestones and Belgian blocks. Accelerometers were installed throughout the truck trailer chassis longitudinal length in order to obtain the acceleration levels and vibration frequencies on the truck trailer sprung mass. Aiming to evaluate the base excitation imposed to parts mounted to the truck trailers chassis, according to their mounting position, data processing method and cutoff frequency definition strategies were defined.
2016-09-27
Technical Paper
2016-01-8153
Prashanth Gururaja
Abstract To investigate the feasibility of various test procedures to determine aerodynamic performance for the Phase 2 Greenhouse Gas (GHG) Regulations for Heavy-Duty Vehicles in the United States, the US Environmental Protection Agency commissioned, through Southwest Research Institute, constant-speed torque tests of several heavy-duty tractors matched to a conventional 53-foot dry-van trailer. Torque was measured at the transmission output shaft and, for most tests, also on each of the drive wheels. Air speed was measured onboard the vehicle, and wind conditions were measured using a weather station placed along the road side. Tests were performed on a rural road in Texas. Measuring wind-averaged drag from on-road tests has historically been a challenge. By collecting data in various wind conditions at multiple speeds over multiple days, a regression-based method was developed to estimate wind-averaged drag with a low precision error for multiple tractor-trailer combinations.
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