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Viewing 91 to 120 of 10390
2016-04-05
Technical Paper
2016-01-1313
Brian Pinkelman, Woo-Keun Song
Abstract Most methods of vibration analysis focus on measuring the level of vibration. Some methods like ISO-2631 weigh vibration level based on human sensitivity of location, direction, and frequency. Sound can be similarly measured by sound pressure level in dB. It may also be weighted to human frequency sensitivity such as dBA but sound and noise analysis has progressed to measure sound quality. The characteristic and the nature of the sound is studied; for example equal or near equal sound levels can provide different experiences to the listener. Such is the question for vibration; can vibration quality be assessed just as sound quality is assessed? Early on in our studies, vibration sensory experts found a difference in 4 seats yet no objective measurement of vibration level could reliably confirm the sensory experience. Still these particular experiences correlated to certain verbal descriptors including smoothness/roughness.
2016-04-05
Technical Paper
2016-01-1683
Blago B. Minovski, Lennart Lofdahl, Peter Gullberg
Abstract Presented are results from numerical investigations of buoyancy driven flow in a simplified representation of an engine bay. A main motivation for this study is the necessity for a valid correlation of results from numerical methods and procedures with physical measurements in order to evaluate the accuracy and feasibility of the available numerical tools for prediction of natural convection. This analysis is based on previously performed PIV and temperature measurements in a controlled physical setup, which reproduced thermal soak conditions in the engine compartment as they occur for a vehicle parked in a quiescent ambient after sustaining high thermal loads. Thermal soak is an important phenomenon in the engine bay primarily driven by natural convection and radiation after there had been a high power demand on the engine. With the cooling fan turned off and in quiescent environment, buoyancy driven convection and radiation are the dominating modes of heat transfer.
2016-04-05
Technical Paper
2016-01-1512
Jeya Padmanaban, Roger Burnett, Andrew Levitt
Abstract This paper updates the findings of prior research addressing the relationship between seatback strength and likelihood of serious injury/fatality to belted drivers and rear seat occupants in rear-impact crashes. Statistical analyses were performed using 1995-2014 CY police-reported crash data from seventeen states. Seatback strength for over 100 vehicle model groupings (model years 1996-2013) was included in the analysis. Seatback strength is measured in terms of the maximum moment that results in 10 inches of seat displacement. These measurements range from 5,989 in-lbs to 39,918 in-lbs, resulting in a wide range of seatback strengths. Additional analysis was done to see whether Seat Integrated Restraint Systems (SIRS) perform better than conventional belts in reducing driver and rear seat occupant injury in rear impacts. Field data shows the severe injury rate for belted drivers in rear-impact crashes is less than 1%.
2016-04-05
Technical Paper
2016-01-1504
Monica Lynn Haumann Jones, Sheila Ebert-Hamilton, Matthew Reed
Abstract Law enforcement officers (LEO) make extensive use of vehicles to perform their jobs, often spending large portions of a shift behind the wheel. Few LEO vehicles are purpose-built; the vast majority are modified civilian vehicles. Data from the field indicate that LEO suffer from relatively high levels musculoskeletal injury that may be due in part to poor accommodation provided by their vehicles. LEO are also exposed to elevated crash injury risk, which may be exacerbated by a compromise in the performance of the occupant restraint systems due to body-borne equipment. A pilot study was conducted to demonstrate the application of three-dimensional anthropometric scanning and measurement technology to address critical concerns related to vehicle design. Detailed posture and belt fit data were gathered from five law enforcement officers as they sat in the patrol vehicles that they regularly used and in a mockup of a mid-sized vehicle.
2016-04-05
Technical Paper
2016-01-1416
Rambabu Radakrishnan, Ganesh Dharmar, Mohanraj Balakrishnan, Sarath Padattil
Abstract Infotainment screens have become critical interface between occupant and Vehicle. Historical development of In-vehicle infotainment (IVI) has shown us the growth of interface size and usability is tremendously increased. The basic small segmented displays of past decades have transformed into large touch screen interface [1]. Earlier small screen interfaces had minimal information and less driver assist functions. It was mainly entertainment based information, which does not require much attention from driver. But recently it has changed from glancing the screen to seeing the screen, due to increased driver assist functions like GPS navigation etc. The amount of information displayed is also increased tremendously [2]. This scenario demands that the infotainment screen positioning inside the vehicle should be free from any visual obscuration, reflection and direct illumination on the infotainment screen due to ambient lighting.
2016-04-05
Technical Paper
2016-01-1443
Nazan Aksan, Lauren Sager, Sarah Hacker, Benjamin Lester, Jeffrey Dawson, Matthew Rizzo
Abstract We examined relative effectiveness of heads-up visual displays for lane departure warning (LDW) 39 younger to middle aged drivers (25-50, mean = 35 years) and 37 older drivers (66-87, mean = 77 years). The LDW included yellow “advisory” visuals in the center screen when the driver started drifting toward the adjacent lane. The visuals turned into red “imminent” when the tires overlapped with the lane markers. The LDW was turned off if the driver activated the turn signal. The visuals could be easily segregated from the background scene, making them salient but not disruptive to the driver’s forward field of view. The visuals were placed adjacent to the left and right lane markers in the lower half of the center screen.
2016-04-05
Technical Paper
2016-01-1444
Shayne McConomy, Johnell Brooks, Paul Venhovens, Yubin Xi, Patrick Rosopa, John DesJardins, Kevin Kopera, Kathy Lococo
Abstract The research objective was to measure and understand the preferred seat position of older drivers and younger drivers within their personal vehicles to influence recommended practices and meet the increased safety needs of all drivers. Improper selection of driver’s seat position may impact safety during a crash event and affect one’s capacity to see the roadway and reach the vehicle’s controls, such as steering wheel, accelerator, brake, clutch, and gear selector lever. Because of the stature changes associated with ageing and the fact that stature is normally distributed for both males and females, it was hypothesized that the SAE J4004 linear regression would be improved with the inclusion of gender and age terms that would provide a more accurate model to predict the seat track position of older drivers. Participants included 97 older drivers over the age of 60 and 20 younger drivers between the ages of 30 to 39.
2016-04-05
Technical Paper
2016-01-1436
K. Han Kim, Sheila Ebert-Hamilton, Matthew Reed
Abstract Automotive seats are commonly described by one-dimensional measurements, including those documented in SAE J2732. However, 1-D measurements provide minimal information on seat shape. The goal of this work was to develop a statistical framework to analyze and model the surface shapes of seats by using techniques similar to those that have been used for modeling human body shapes. The 3-D contour of twelve driver seats of a pickup truck and sedans were scanned and aligned, and 408 landmarks were identified using a semi-automatic process. A template mesh of 18,306 vertices was morphed to match the scan at the landmark positions, and the remaining nodes were automatically adjusted to match the scanned surface. A principal component (PC) analysis was performed on the resulting homologous meshes. Each seat was uniquely represented by a set of PC scores; 10 PC scores explained 95% of the total variance. This new shape description has many applications.
2016-04-05
Technical Paper
2016-01-1437
Giorgio Previati, Massimiliano Gobbi, Giampiero Mastinu
Abstract The paper is focused on both the subjective and the objective ride comfort evaluation of farm tractors. The experimental measurement of the relevant accelerations occurring at the tractor body, at the cabin and at the seat was performed on a number of different farm tractors. A subjective rating of the ride comfort level was performed by considering five different drivers. The comfort index was computed according with ISO 2631 and other standards. The acceleration of the seated subject was computed by means of a proper mechanical model of a farm tractor and derived at different positions on the subject body. It turned out that the acceleration of the lower torso was particularly relevant for establishing a matching between the subjective perception and the objective measurement and computation. A number of indices have been derived from the measured data which are able to correlate the subjective driver feeling with the measured accelerations.
2016-04-05
Technical Paper
2016-01-1438
Alexander Siefert
Abstract The objective evaluation of occupant comfort is a complex task where numerous aspects such as posture, pressure distribution, internal tissue loads, handling of steering wheel or gear shift have to be taken into consideration. Currently the standard evaluation procedures are hardware tests with human subjects, who are sensitive to all these aspects. However, the reproducibility of subjective tests for the comparison of design variants is a questionable issue and the costs for each test cycle with new prototypes are very high. As an alternative, numerical approaches using human body models such as AnyBody [1], CASIMIR [2] or RAMSIS [3] are applied. Here the issue of reproducibility does not exist and only little effort is required to investigate new setups. However, the disadvantage is that each approach focuses only on one specific aspect of occupant comfort, while in reality the emotions of the occupant are always a combination of all impressions.
2016-04-05
Technical Paper
2016-01-1429
Jangwoon Park, Sheila Ebert-Hamilton, K. Han Kim, Monica Jones, Byoung-Keon Park, Matthew Reed
Abstract This paper reports on the development and validation of an automated seat-dimension extraction system that can efficiently and reliably measure SAE J2732 (2008) seat dimensions from 3D seat scan data. The automated dimension-extraction process consists of four phases: (1) import 3D seat scan data along with seat reference information such as H-point location, back and cushion angles, (2) calculate centerline and lateral cross-section lines on the imported 3D seat scan data, (3) identify landmarks on the centerline and cross-section lines based on the SAE J2732 definitions, and (4) measure seat-dimensions using the identified landmarks. To validate the automated seat measurements, manually measured dimensions in a computer-aided-design (CAD) environment and automatically extracted ones in the current system were compared in terms of mean discrepancy and intra- and inter-observer standard deviations (SD).
2016-04-05
Technical Paper
2016-01-1430
Se Jin Park, Murali Subramaniyam, Seoung Eun Kim, Tae Hyun Kim, Hee Su Sin, Dong Hag Seo, Hyu Hyeong Nam, Jeong Cheol Lee
Abstract Seating comfort is associated with the various factors, and one of the principal components of a vehicle environment which can affect passenger’s comfort is vibration. The seat design plays a vital role in the vibration isolation. In recent years, automotive seat designers are paying more attention for the improvement of seat cushion properties. This paper provides information about a new automotive seat concept that use double-wall 3D air-mat in cushion along with foam cushion in the seat cushion system. To test the developed seat on vibration isolation characteristics, seating comfort, and ride quality experiments have been performed. This research is divided into two parts. At first, the newly developed seat tested on the motion simulator. In study 2, road tests were performed on the national highway. Two tri-axial accelerometers were used to measure acceleration at the foot and hip in two different seats (seat with and without double-wall 3D air-mat).
2016-04-05
Technical Paper
2016-01-1431
Subramanian Premananth, Ganesh Dharmar, Hareesh Krishnan, Riyaz Mohammed
Abstract 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.
2016-04-05
Technical Paper
2016-01-1432
Alexander Siefert
Abstract Predicting the vibration comfort is a difficult challenge in seat design. There is a broad range of requirements as the load cases strongly vary, representing different excitation levels, e.g. cobblestones or California roads. Another demand is the driver expectation, which is different for a pickup and a sports car. There are several approaches for assessing the vibrations of occupants while driving. One approach is the evaluation of comfort by integral quantities like the SEAT value, taking into account a weighting based on the human body sensitivity. Another approach is the dimension of perception developed by BMW, which is similar to psychoacoustics as the frequency range is separated with respect to occurring vibration phenomena. The seat transmissibility is in the focus of all activities. In the frequency range it defines the relation between the input at the seat slides and the output at the interface of human body and trim.
2016-04-05
Technical Paper
2016-01-1433
Gregory Schaupp, Julia Seeanner, Casey Jenkins, Joseph Manganelli, Sarah Hennessy, Constance Truesdail, Lindsay Swift, Paul Venhovens, Johnell Brooks
Abstract The ability to independently transfer into and out of a vehicle is essential for many wheelchair users to achieve driving independence. This paper presents the results of an exploratory study that investigated the transfer strategies of wheelchair users who drive from their driver’s seat and not from their wheelchair. The goal of this study was to identify typical ingress and egress motions as well as “touch points” of wheelchair users transferring into and out of the driver’s seat. While motion databases exist for the ingress and egress of able-bodied drivers, this study provides insight on drivers with physical disabilities. Twenty-five YouTube videos of wheelchair users who transferred into and out of their own sedans were analyzed.
2016-04-05
Technical Paper
2016-01-1336
Hee Sang Park
Abstract Headliner module system implies that all components, including fasteners that are attached to the headliner substrate panel prior to vehicle assembly installation. The headliner substrate becomes an installation fixture which facilitates the assembly process. Since headliner module is an integration of many separate components into one more complex assembly, prior to vehicle assembly, a number of additional requirements must be considered. Many of these requirements are driven by the factors like shipping, handling and installation of a large panel with various componentry mounted for temporary installation retention or permanent retention. Substrate should be tough but, on the contrary it should be soft enough for the curtain airbag deployment. Tough substrate interferes with airbag deployment. Detachable reinforcement will enhance shipping and handling process. After installation, reinforcement can be detached from headliner module which will keep the substrate soft.
2016-04-05
Technical Paper
2016-01-1211
Hua Tian, WeiGuang Wang, Ge-Qun Shu, Xingyu Liang, Haiqiao Wei
Abstract Power lithium-ion battery is the core component of electric vehicles and hybrid electric vehicles (EVs and HEVs). Thermal management at different operating conditions affects the life, security and stability of lithium-ion battery pack. In this paper, a one-dimensional, multiscale, electrochemical-thermal coupled model was applied and perfected for a flat-plate-battery pack. The model is capable of predicting thermal and electrochemical behaviors of battery. To provide more guidance for the selection of thermal management, temperature evolutions and distributions in the battery pack at various ambient temperatures, discharge rates and thermal radiation coefficients were simulated based on six types of thermal management (adiabatic, natural convection, air cooling, liquid cooling, phase change material cooling, isothermal).
2016-04-05
Technical Paper
2016-01-1204
Dongchang Pan, Sichuan Xu, Chunjing Lin, Guofeng Chang
Abstract As one of the most crucial components in electric vehicles, power batteries generate abundant heat during charging and discharging processes. Thermal management system (TMS), which is designed to keep the battery cells within an optimum temperature range and to maintain an even temperature distribution from cell to cell, is vital for the high efficiency, long calendar life and reliable safety of these power batteries. With the desirable features of low system complexity, light weight, high energy efficiency and good battery thermal uniformity, thermal management using composite phase change materials (PCMs) has drawn great attention in the past fifteen years. In the hope of supplying helpful guidelines for the design of the PCM-based TMSs, this work begins with the summarization of the most commonly applied heat transfer enhancement methods (i.e., the use of thermally conductive particles, metal fin, expanded graphite matrix and metal foam) for PCMs by different researchers.
2016-04-05
Technical Paper
2016-01-1238
Paul Karoshi, Karin Tieber, Christopher Kneissl, Georg Peneder, Harald Kraus, Martin Hofstetter, Jurgen Fabian, Martin Ackerl
Abstract In hybrid electric vehicles (HEV), the operation strategy strongly influences the available system power, as well as local exhaust emissions. Predictive operation strategies rely on knowledge of future traction-force demands. This predicted information can be used to balance the battery’s state of charge or the engine’s thermal system in their legal operation limits and can reduce peak loads. Assuming the air and rolling drag-coefficient to be constant, the desired vehicle velocity, vehicle-mass and longitudinal driving resistances determine the vehicle’s traction-force demand. In this paper, a novel methodology, combining a history-based prediction algorithm for estimating future traction-force demands with the parameter identification of road grade angle and vehicle mass, is proposed. It is solely based on a route-history database and internal vehicle data, available on its on-board communication and measuring systems.
2016-04-05
Technical Paper
2016-01-1355
Jeffrey R. Hodgkins, Walter Brophy, Thomas Gaydosh, Norimasa Kobayashi, Hiroo Yamaoka
Abstract Current vehicle acoustic performance prediction methods, CAE (computer aided engineering) or physical testing, have some difficulty predicting interior sound in the mid-frequency range (300 to 1000 Hz). It is in this frequency range where the overall acoustic performance becomes sensitive to not only the contributions of structure-borne sources, which can be studied using traditional finite element analysis (FEA) methods, but also the contribution of airborne noise sources which increase proportional to frequency. It is in this higher frequency range (>1000 Hz) that physical testing and statistical CAE methods are traditionally used for performance studies. This paper will discuss a study that was undertaken to test the capability of a finite element modeling method that can accurately simulate air-borne noise phenomena in the mid-frequency range.
2016-04-05
Technical Paper
2016-01-1417
Toshinao Fukui, Kazuhiko Nakamoto, Hiroyuki Satake
Abstract The use of a head-up display (HUD) system has become popular recently, as it can provide feedback information at a position easily seen by the driver. However, the outline of the HUD bezel often reflects on the windshield of a HUD equipped vehicle. This phenomenon occurs when the sun is at a high position and reflects off the top of the instrument panel and the front view is dark. For this reason, it can occur when driving on asphalt paved roads, causing annoyance to the driver. Under fixed environmental conditions, the vehicle based factors that influence the annoyance caused by reflected boundary lines are the position of the reflection, line thickness, and the contrast of the reflected boundary line. These can be represented by the conspicuity of a striped pattern (contrast sensitivity function). In previous research in 1991, M. S. Banks et al. studied a contrast sensitivity function that included the factors stated above.
2016-04-05
Technical Paper
2016-01-0823
Jason Miwa, Darius Mehta, Chad Koci
Abstract Increasingly stringent emissions regulations require that modern diesel aftertreatment systems must warm up and begin controlling emissions shortly after startup. While several new aftertreatment technologies have been introduced that focus on lowering the aftertreatment activation temperature, the engine system still needs to provide thermal energy to the exhaust for cold start. A study was conducted to evaluate several engine technologies that focus on improving the thermal energy that the engine system provides to the aftertreatment system while minimizing the impact on fuel economy and emissions. Studies were conducted on a modern common rail 3L diesel engine with a custom dual loop EGR system. The engine was calibrated for low engine-out NOx using various combustion strategies depending on the speed/load operating condition.
2016-04-05
Technical Paper
2016-01-0892
Oliver P. Taylor, Richard Pearson, Richard Stone
Abstract Most major regional automotive markets have stringent legislative targets for vehicle greenhouse gas emissions or fuel economy enforced by fiscal penalties. Large improvements in vehicle efficiency on mandated test cycles have already taken place in some markets through the widespread adoption of technologies such as downsizing or dieselisation. There is now increased focus on approaches which give smaller, but significant incremental efficiency benefits, such as reducing parasitic losses due to engine friction. The reduction in tail pipe CO2 emissions through the reduction of engine friction using lubricants has been reported by many authors. However, opportunities also exist to reduce the lubricant viscosity during warm up by the thermal management of the lubricant mass.
2016-04-05
Technical Paper
2016-01-1295
Atsushi Itoh, ZongGuang Wang, Toshikazu Nosaka, Keita Wada
Abstract Without engine noise, the cabin of an electric vehicle is quiet, but on the other hand, it becomes easy to perceive refrigerant-induced noise in the automotive air-conditioning (A/C) system. When determining the A/C system at the design stage, it is crucial to verify whether refrigerant-induced noise occurs in the system or not before the real A/C systems are made. If refrigerant-induced noise almost never occurs during the design stage, it is difficult to evaluate by vehicle testing at the development stage. This paper presents a 1D modeling methodology for the assessment of refrigerant-induced noise such as self-excitation noise generated by pressure pulsation through the thermal expansion valve (TXV). The GT-SUITE commercial code was used to develop a refrigerant cycle model consisting of a compressor, condenser, evaporator, TXV and the connecting pipe network.
2016-04-05
Technical Paper
2016-01-1410
Stefan G. Grötsch, Morten Brink, Roland Fiederling, Thomas Liebetrau, Ingo Möllers, Jörg Moisel, Hermann Oppermann, Alexander Pfeuffer
Abstract A cooperation of several research partners supported by the German Federal Ministry of Research and Education proposes a new active matrix LED light source. A multi pixel flip chip LED array is directly mounted to an active driver IC. A total of 1024 pixel can be individually addressed through a serial data bus. Several of these units are integrated in a prototype headlamp to enable advanced light distribution patterns in an evaluation vehicle.
2016-04-05
Technical Paper
2016-01-0008
Johnathan Putrus, Stanley Jones, Badih Jawad, Giscard Kfoury, Selin Arslan, Peter Schihl
Thermal management systems (TMS) of armored ground vehicle designs are often incapable of sustained heat rejection during high tractive effort conditions and ambient conditions. During these conditions, which mainly consist of high torque low speed operations, gear oil temperatures can rise over the allowable 275°F limit in less than twenty minutes. This work outlines an approach to temporarily store excess heat generated by the differential during high tractive effort situations through the use of a passive Phase Change Material (PCM) retrofit thereby extending the operating time, reducing temperature transients, and limiting overheating. A numerical heat transfer model has been developed based on a conceptual vehicle differential TMS. The model predicts the differential fluid temperature response with and without a PCM retrofit. The developed model captures the physics of the phase change processes to predict the transient heat absorption and rejection processes.
2016-04-05
Technical Paper
2016-01-0080
Hiroyuki Miyake
Abstract This paper explains a performance enhancement of the lane guidance function in car navigation systems. In order to achieve intuitive lane guidance, a function is considered that displays lane guidance on an image of the front scene that matches what drivers actually see outside the vehicle. Therefore, two developed items were lane accurate positioning based on image recognition and augmented reality visualization that renders lane guidance images overlaid on the scenery of the road ahead. The eye glance time to the navigation screen has been reduced in a comparison test with a conventional lane guidance method. It is confirmed that this lane guidance function is more intuitive than the conventional method.
2016-04-05
Technical Paper
2016-01-0100
Sushant Kishor Hingane
High-end vehicles with latest technology and autonomous driving experience have to bear the cost of increasing number of sensors on-board. It would be beneficial to reduce some of the sensors in the vehicle and make use of other available resources, retaining the same functionality. This paper discusses a novel technique of estimating the weight of seat occupant from an already existing DC motor without using additional pressure sensors. Passenger weight information is important for seat-belt reminder system as well as supplemental restraint system that will decide the air-bag deployment. The mathematical model for a series-type DC motor is analyzed and simulated using MATLAB. Further, results of the experiment performed on a lower capacity motor are shared and compared with the simulation results. Formulating a linear relation gives a possibility to develop a device for occupant weight measurement inside the high-end vehicles.
2016-04-05
Technical Paper
2016-01-0641
Thomas De Cuyper, Sam Bracke, Jolien Lavens, Stijn Broekaert, Kam Chana, Michel De Paepe, Sebastian Verhelst
Abstract To optimize internal combustion engines (ICEs), a good understanding of engine operation is essential. The heat transfer from the working gases to the combustion chamber walls plays an important role, not only for the performance, but also for the emissions of the engine. Besides, thermal management of ICEs is becoming more and more important as an additional tool for optimizing efficiency and emission aftertreatment. In contrast little is known about the convective heat transfer inside the combustion chamber due to the complexity of the working processes. Heat transfer measurements inside the combustion chamber pose a challenge in instrumentation due to the harsh environment. Additionally, the heat loss in a spark ignition (SI) engine shows a high temporal and spatial variation. This poses certain requirements on the heat flux sensor. In this paper we examine the heat transfer in a production SI ICE through the use of Thin Film Gauge (TFG) heat flux sensors.
2016-04-05
Technical Paper
2016-01-0648
Sinan Eroglu, Ipek Duman, Alp Ergenc, Rıfat Yanarocak
Abstract The exhaust manifold bridges the gap between the engine structure and the hot-end after-treatment system, the burned in-cylinder gases are disposed through the manifold. The automotive exhaust manifolds are designed and developed for providing a smooth flow with low/least back pressure and must be able to withstand extreme heating under very high temperatures and cooling under low temperatures. The paper presents a theoretical study aiming to investigate the feasibility of three different CAE approaches and techniques used for the simulation of exhaust manifold fluid flow and the accompanying thermal distribution. The main difficulty emanates from the pulsating nature of fluid flow inside the engine exhaust manifold. To verify the outcome of each solution experimental measurements of the manifold temperatures have been performed.
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