Criteria

Display:

Results

Viewing 241 to 270 of 5932
2015-09-29
Technical Paper
2015-01-2766
Sai Venkatesh Muravaneni, Egalaivan Srinivasan, Jagankumar Mari
Abstract Steering wheel being the most used tactile point in a vehicle, its feel and response is an important factor based on which the vehicle quality is judged. Engineering the right feel and response into the system requires knowledge of the objective parameters that relate to the driver perception. Extensive correlation work has been done in the past pertaining to passenger cars, but the driver requirements for commercial vehicles vary significantly. Often it becomes difficult to match the right parameters to the steering feel experienced by the drivers, since most of the standard ISO weave test units used to describe them are of zero or first order parameters. Analyzing the second order parameters gave a better method to reason driver related feel. Also, each subjective attribute was fragmented into sub-attributes to identify the reason for such a rating resulting in the identification of the major subjective parameters affecting driver ratings.
2015-09-29
Technical Paper
2015-01-2868
John Woodrooffe, Daniel Blower
Abstract This paper examines truck driver injury and loss of life in truck crashes related to cab crashworthiness. The paper provides analysis of truck driver fatality and injury in crashes to provide a better understanding of how injury occurs and industry initiatives focused on reducing the number of truck occupant fatalities and the severity of injuries. The commercial vehicle focus is on truck-tractors and single unit trucks in the Class 7 and 8 weight range. The analysis used UMTRI's Trucks Involved in Fatal Accidents (TIFA) survey file and NHTSA's General Estimates System (GES) file for categorical analysis and the Large Truck Crash Causation Study (LTCCS) for a supplemental clinical review of cab performance in frontal and rollover crash types. The paper includes analysis of crashes producing truck driver fatalities or injuries, a review of regulatory development and industry safety initiatives including barriers to implementation.
2015-09-29
Journal Article
2015-01-2834
James Roger Lackore, Kevin Voss
Abstract Access method design for entry and egress of medium and heavy duty truck cabs and bodies is a critical aspect of vehicle design. Occupational injuries due to entering or exiting the truck cab, or climbing onto and off of the truck body, can be a significant percentage of a fleet's lost-time incident rate. Many vocational trucks operate in both off-road and on-road conditions, and the slip resistance of the stepping surface is an important design aspect. Examples of vocational vehicles that involve off-road operation include dump, refuse, utility, tree-trimming, and concrete trucks. Stepping surfaces in these applications must provide a balance between traction and the ability to shed water, snow, and mud. While there are a few methods and devices for measuring walking surface slip resistance, they are either complicated, or not well suited to measuring aggressive surfaces.
2015-09-29
Journal Article
2015-01-2843
Xu Kuang, Jianqiang Wang, Keqiang Li
Abstract Transport vehicles consume a large amount of fuel with low efficiency, which is significantly affected by drivers' behaviors. An assessment system of eco-driving pattern for buses could identify the deficiencies of driver operation as well as assist transportation enterprises in driver management. This paper proposes an assessment method regarding drivers' economic efficiency, considering driving conditions. To this end, assessment indexes are extracted from driving economy theories and ranked according to their effect on fuel consumption, derived from a database of 135 buses using multiple regression. A layered structure of assessment indexes is developed with application of AHP, and the weight of each index is estimated. The driving pattern score could be calculated with these weights.
2015-09-29
Journal Article
2015-01-2870
Sanket Pawar
Abstract Displacement joystick controls are considered as most suitable for manual controls wherever proportional outputs are required for dynamic applications such as when variable speed sensitivity or position are required. These joysticks are being used widely in both open loop as well as in close loop controls. The operator applies force to either the joystick itself or to its proportional linear displacement thumb wheel switches. This movement is then detected by either resistive or Hall Effect sensors, placed right inside joystick, and converted into an electrical signal. These joysticks, along with proportional linear displacement thumb wheel switches, find a wide range of applications in off-road vehicles such construction and forestry vehicles, harvester machines, and etc. for applications like attachment speed controls, boom position control, rotation speed control, and etc.
2015-09-29
Technical Paper
2015-01-2767
Sanjay Lakshmanan, Arthanareeswaran Palaniappan, Vijayakumar Chekuri
Abstract The emerging trends in commercial vehicle technology have increased the necessity for critical attribute engineering refinements. Drivability is emerging as one of the most significant attributes in the automotive sector. The degree of smoothness in a vehicle's response to the driver's input is termed as drivability. This attribute has to be rigorously refined in order to achieve brand specific vehicle characteristics, which will ensure a thorough product differentiation. In order to calibrate for a positive drivability feel, a methodology for evaluation of drivability is a prerequisite. The scope of this paper is aimed at describing the methodology for subjective and objective evaluation of drivability attributes in commercial vehicles. Drivability is a highly subjectively perceived attribute, therefore a subjective assessment technique to assess drivability attributes and sub-attributes are essential.
2015-09-27
Technical Paper
2015-01-2696
Shuichi Okada
We had developed Electric Servo Brake System, which can control brake pressure accurately with a DC motor according to brake pedal force. Therefore, the system attains quality brake feeling while reflecting intentions of a driver. By the way, “Build-up” is characteristics that brake effectiveness increases in accordance with the deceleration of the vehicle, which is recognized as brake feeling with a sense of relief as not to elongate an expected braking distance at a downhill road due to large-capacity brake pad such as sports car and large vehicles. Then, we have applied the optical characteristic control to every car with Electric Servo Brake System by means of brake pressure control but not brake pad. Hereby, we confirmed that the control gives a driver the sense of relief and the reduction of pedal load on the further stepping-on of the pedal. In this paper, we describe the development of brake feel based on the control overview.
2015-09-27
Technical Paper
2015-01-2674
Dragan Aleksendric, Velimir Cirovic, Dusan Smiljanic
Abstract Customer perception of brake pedal feel quality, depends on both the customer's subjective judgment of quality and the actual build quality of the brake system. The brake performance stability represents an important aspect of a vehicle performance and its quality of use. This stability is needed especially in brake by wire system and braking system with regenerative braking. In order to provide stable braked pedal feel i.e. consistent the brake performance against the brake pedal travel, the model of the brake performance versus the brake pedal travel needs to be established. In this paper new hybrid neuro-genetic optimization model was developed for dynamic control and optimization of the disc brake performance during a braking cycle versus the brake pedal travel. Based on such model, the brake performance optimization of the passenger car has been provided against the brake pedal travel.
2015-09-22
Technical Paper
2015-36-0205
Heloisa Rodrigues Lourenço, Marko Ackermann
Abstract Vehicle ergonomics, more specifically driver ergonomics, has been the subject of interest in the automotive industry as a way to provide customers vehicles that have more than modern project, efficiency and competitive price. The driver ergonomics is related to the way the driver interacts with the vehicle interior, particularly, with the seat, hand and foot controls, considering aspects such as ease of access, space, proper upper and lower limb motion and drivers comfort and fatigue. Regarding the lower limbs, the driver’s comfort can be evaluated in terms of joint moments and muscle forces, which are influenced by the hip, knee and ankle joint angles, which in turn depend on the distances between the seat and pedal.
2015-09-22
Technical Paper
2015-36-0211
Bruno Afonso, Walace Chicuta, Roberto Bortolussi
Abstract This paper shows the elaboration of studies about the driver’s comfort in a Baja SAE vehicle in different track conditions. The multibody model was designed in ADAMS VIEW software with full vehicle components aim evaluate frequencies, accelerations and displacements in any part of the vehicle. Several tests and measurements were made to acquire springs, dampers and tire data to ensure the model represents the real vehicle. The full vehicle and also the driver were modeled through a CAD software, thus all geometries, mass and inertias were inputted in the multibody model based on the built vehicle. The vertical displacements were modeled in the multibody software simulating the road profile, so it was possible to analyze the vehicle ride behavior with different set ups in different tracks. The validation of multibody mathematical model was made by modeling the same maneuver that the vehicle instrumented with data acquisition was submitted.
2015-09-22
Technical Paper
2015-36-0164
Alexandre Rodrigues Pinho, Cleber P. Franco
Abstract Basic driveline configurations offered in mid-size trucks have a standard “open” differential. Open differentials allow smooth cornering, as the outside tire must spin faster on corners as it travels a larger arc, when compared to the inner tire. This system has a main problem when traction is lost, due to slippery roads, different friction coefficients between pavements or even when the axle is submitted to a twist ditch. All of the power goes to the wheel with the least traction and the pickup is stuck. In order to improve traction on these situations, limited slip differentials were developed. A limited-slip differential will prevent excessive power from being allocated just to one wheel, and thereby keeping both wheels in powered rotation. There are several solutions offered in the market, each one presenting different torque transfer capabilities.
2015-09-15
Technical Paper
2015-01-2401
Michael Schmidt, Philipp Nguyen, Mirko Hornung
Abstract The projected uptick in world passenger traffic challenges the involved stakeholders to optimise the current aviation system and to find new solutions being able to cope with this trend. Since especially large hub airports are congested, operate at their capacity limit and further extensions are difficult to realise. Delays due to late arrival of aircraft or less predictable ground operation processes disrupt the airport operations in a serious way. Various concepts improving the current turnaround processes have been presented thus far, whereby radical aircraft design changes have little chances for realisation in the short term. By maintaining the established overall aircraft configuration, the concepts promote higher probability to become commercially available for aircraft manufactures and operators.
2015-09-15
Technical Paper
2015-01-2429
Rickard Olsen, Kerstin Johansen, Magnus Engstrom
Abstract The increased diffusion of cooperation between humans and robotics in manufacturing systems is one of the next things to implement within robotics. Since the computer power gets more and more powerful, the possibilities increase to achieve safer working environment, due to that all safety signals demands fast management of data. This could lead to a possibility to work closer and more direct with a robot, using the robot as a third hand. Within an EU FW7 funded project called LOCOMACHs (Low Cost Manufacturing and Assembly of Composite and Hybrid Structures) there are one study focusing on how to support a future higher TRL-leveled HMI cell (Human Machine Interaction) in an assembly task. The main objective in this paper is to present how different external safety systems could support the whole HMI assembly cell to work properly in an industrial context.
2015-09-15
Technical Paper
2015-01-2601
Zhejun Yao, Wiltrud Weidner, Robert Weidner, Jens Wulfsberg
Abstract Despite the increasing application of automated systems, manual tasks still plays an important role in industrial production. The intelligence and flexibility of human enable quick response and adaptive production for the individual requirements and the changes in market. Moreover, some manufacturing tasks with sensible and high-value components (e.g., in electronic and aircraft production) requires attentive manual handling. Regarding the requirement of increasing productivity as well as ergonomic improvement and the aging of the employees, there is a significant need for technologies which support the staff individually by performing tasks. Human Hybrid Robot, a hybrid system with direct coupling (serial and/or parallel) of human and mechatronic elements, is a new trend in application of robotic technologies for supporting manual tasks. It realizes a synchronous and bidirectional interaction between human and mechatronic and/or mechanic elements in the same workspace.
2015-09-15
Technical Paper
2015-01-2536
Rinky Babul Prasad, Vinukonda Siddartha
Abstract Recent years have seen a rise in the number of air crashes and on board fatalities. Statistics reveal that human error constitutes upto 56% of these incidents. This can be attributed to the ever growing air traffic and technological advancements in the field of aviation, leading to an increase in the electronic and mechanical controls in the cockpit. Accidents occur when pilots misinterpret gauges, weather conditions, fail to spot mechanical faults or carry out inappropriate actions. Currently, pilots rely on flight manuals (hard copies or an electronic tablet) to respond to an emergency. This is prone to human error or misinterpretation. Also, a considerable amount of time is spent in seeking, reading, interpreting and implementing the corrective action. The proposed augmented head mount virtual assist for the pilot eliminates flight manuals, by virtually guiding the pilot in responding to in-flight necessities.
2015-09-15
Technical Paper
2015-01-2537
Sylvain Hourlier
Abstract The efficiency of the glass cockpit paradigm has faded away with the densification of the aeronautical environment. Today's problem lies with “non-defective aircraft” monitored by “perfectly trained crews” still involved in fatal accidents. One explanation is, at crew level, that we have reached a system complexity that, while acceptable in normal conditions, is hardly compatible with human cognitive abilities in degraded conditions. The current mitigation of such risk still relies on the enforcement through intensive training of an ability to manage extremely rare (off-normal) situations. These are explained by the potential combination of failures of highly complex systems with variable environment & with variable humans.
2015-09-15
Journal Article
2015-01-2440
Robert Moehle, Jason Clauss
Abstract Labor costs rank second only to fuel in expenses for commercial air transports. Labor issues are a growing concern in the airline industry, with an impending worldwide pilot shortage. One solution proposed and requested by some of the industry leaders is to allow a single flight crew member to operate the aircraft. Safety concerns represent the dominant barrier to single-pilot Part 121 operations. The FAA and Congress consistently demonstrate a bias toward conservatism in their regulation of airlines and commercial aircraft. Bureaucrats and the general public fall prey to isolated news stories that highlight pilot error and anchor their viewpoint on further regulating a two-person crew. Yet, in an alarming spate of recent airline accidents, the presence of multiple crewmembers did nothing to prevent, and actually may have contributed to, the crash. Technology is not the problem.
2015-09-15
Journal Article
2015-01-2532
Sylvain Hourlier, Sandra Guérard, Jean Luc BAROU, Xavier Servantie
Abstract As touch screens are everywhere in the consumer market Thales has launched in depth evaluations on their introduction in the cockpit. One of the challenges is to verify its compatibility with in flight use under turbulence conditions, including light, moderate and severe. In flight accelerometer collections were performed to provide us with a baseline for choosing between possible simulation solutions. Thales recognized early on the need for such a tool as it would enable us to define recommendations for our HMI designs. The objectives were first to validate specific complex touch/gestures using all the potential of touch interactions for novel cockpit Human Machine Interfaces and second to look into the various physical anchoring solutions capable of facilitating touch screens interactions in aeronautical turbulent environments.
2015-09-15
Journal Article
2015-01-2485
Mark Benjamin Geiger, John Michael Ster
Abstract A joint US Department of Defense (DOD), General Services Administration (GSA) and National Institute for Occupational Safety and Health (NIOSH) project initially addressing procurement criteria for powered hand tools stimulated involvement of the SAE EG1-B Hand Tools committee and affiliated industry participants, producers of powered hand tools. It became apparent of the need to develop a standard that addresses occupational disease, productivity, life-cycle cost in the selection of Hand Power Tools. Committee efforts focused upon development of an SAE International Standard that considers productivity hand-arm vibration, noise, other safety and health factors and life-cycle costs in procurement criteria for powered hand tools. Aerospace Standard, AS 6228 Safety Requirements for Procurement, Maintenance and Use of Hand-held Powered Tools, was published in September 2014.
2015-06-15
Technical Paper
2015-01-2338
Dong Guo, Quan Shi, Peng Yi
Abstract In-vehicle noise is composed of a variety of tonal (frequency-related) components and the tonal components play an important role in the improvement of interior vehicle sound quality. Much research has been focused on the suppression of sound pressure level and achieved certain positive effects. However, in some operating conditions, customers still perceive the tonal components and complain about the vehicle quality even the sound pressure level is relatively low. Therefore, a better understanding of how tonal components are perceived is necessary for automotive designers. To do so, psychoacoustics results about human hearing mechanism to tonal components are comprehensively summed in this study: human hearing response to pure tone, two tones and multiple tones. Then, well-controlled testing stimuli were generated and subjective annoyance testing was conducted. The results show agreement with former researchers' findings.
2015-06-15
Technical Paper
2015-01-2352
Chaitanya Krishna Balla, Sudhakara Naidu, Milind Narayan Ambardekar
Abstract Noise Vibration and Harshness (NVH) refinement is one of the important parameters in modern vehicle development. In city traffic conditions, idling is an engine operating condition where a driver focuses attention more to his/her vehicle. Tactile vibration & noise levels inside the cab play an important role in all vehicles, especially those powered by diesel engines where combustion pressures are higher. They lead to discomfort & fatigue of passengers of even a low cost vehicle. Now its idle NVH is influenced mainly by vibration-isolation provided by power-train (PT) mounting design, This paper describes steps taken to improve the idle vibrations at a driver seat of a small commercial vehicle (SCV) with a 2-cylinder diesel engine of 800 cc through redesign of PT-mounting along with fine tuning of idle speed of the engine. A resonance was avoided between the first firing order at idling and PT rigid-body mode in pitching.
2015-06-15
Technical Paper
2015-01-2271
Yong Du Jun, Bong Hyun Park, Kang Seok Seo, Tae Hyun Kim, Myoung Jae Chae
Abstract Modern automotive seats require improvements in their design, safety, comfort including sitting and riding comfort. Among those, seat comfort is known to be difficult to evaluate because the comfort is a human feeling. As an approach to evaluate the human comfort in an objective manner, an objective measure is proposed for seat riding comfort evaluation under low frequency vibratory conditions which represents typical roll and pitch motions of driving motor vehicles. The related feeling due to this low frequency vehicle motion is termed ‘hold feeling’ because the seated body may tend to deviate from the defined seating position under such vehicle motion input. Dynamic pressure measurements have been conducted in the frequency range up to 1.0 Hz to monitor the interface pressure change behavior of the seat-subject body.
2015-06-15
Technical Paper
2015-01-2332
Jan Deleener, Akira Sekitou, Masanori Ohta
Abstract Shift quality of a gearbox is one of the most important items contributing to the overall subjective impression of driving comfort for a vehicle with a manual transmission. Often the transmission is the only point of attention for shift quality issues with a focus on the synchronizer being the main area of optimization. This is however not always sufficient. What the driver feels at the gear lever is a result of the interaction between the gear lever, the selector system, the transmission internals and the driveline. For most of these subsystems, well established models are available which can be used in early development to get a first idea of the shift quality. However, accurately representing the physical feel of the transmission cable, connecting the gearbox and the shifter, remains a challenge.
2015-06-15
Journal Article
2015-01-2216
Dong Chul Park, Eun Soo Jo, Seokgwan Hong, Michael Csakan
Abstract An important trend among vehicle NVH engineers is the production of attractive engine acceleration sound quality for the enhancement of a vehicle's image and performance. In addition, customers have increasing interest and enjoyment in customizing their cars to reflect their personal taste and preferences. The PESS (Personalized Engine Sound System) has been developed for making a unique and individually customizable vehicle concept. The system allows the customers an opportunity to create a variety of engine sounds in a single vehicle using active sound design technology. In this system, three different engine sound concepts are pre-defined, Dynamic, Sporty, and Extreme. Each of the engine sounds can then be adjusted with parameters that determine the timbre, such as main order, rumble, and high order. In addition, the pedal position during acceleration has also been used as a parameter to further personalize the experience.
2015-06-15
Journal Article
2015-01-2285
Arne Nykänen, David Lennström, Roger Johnsson
Abstract Subjects who are well aware of what to judge commonly yield more consistent results in laboratory listening tests. This awareness may be raised by explicit instructions and training. However, too explicit instructions or use of only trained subjects may direct experiment results in an undesired way. An alternative is to give fairly open instructions to untrained subjects, but give the subjects a chance to get familiar with the product and context by, for example, riding a representative car under representative driving conditions before entering the laboratory. In this study, sound quality assessments of interior sounds of cars made by two groups were compared. In one group subjects were exposed to the same driving conditions that were later assessed in a laboratory listening test by taking them on a ride in one of the cars to be assessed, just before entering the laboratory. In the other group subjects made the laboratory assessments without prior car riding.
2015-06-15
Journal Article
2015-01-2337
Gordon Ebbitt, Todd Remtema
Abstract Speech communication from the front seat to the rear seat in a passenger vehicle can be difficult. This is particularly true in a vehicle with an acoustically absorptive interior. Speech Transmission Index (STI) measurements can quantify the speech intelligibility, but they require specialized signal processing. The STI calculations can be simplified if it is assumed that reverberation and echoes play an insignificant role in an automobile. A simplification of a STI measurement is described that uses a stationary reference speech signal from a talker mannequin in the driver's seat to create a signal at the rear passenger positions. On-road noise measurements are used for the noise level and the calculated signal to noise ratio is used to calculate a simplified STI value that tracks closely to a full implementation of the STI method for sedans.
2015-05-13
Technical Paper
2015-36-0006
Erik Camargo, Claudio Fernandes, Leopoldo Sprandel, Romulo Castro, Rodrigo Sousa, Leandro Roza, Marcio Ciolfi
Abstract This paper focused on pedal feeling studies at most often longitudinal decelerations for the normal daily usage of customers. Such decelerations were defined in vehicle equipped with sensors in a specific itinerary near Resende/Penedo city (southeastern Brazil) with several clients using the same vehicles. Through the decelerations acquired, one could correlate, objectively and subjectively, the pedal effort and travel that delight the customers, reaching the so called ideal pedal feeling. The mapping provides the needed input data to develop, or adapt, a vehicle to the best condition expected by consumers.
2015-04-14
Technical Paper
2015-01-0418
Vijitashwa Pandey, Megan Conrad
Abstract This paper develops a design paradigm for universal products. Universal design is term used for designing products and systems that are equally accessible to and usable by people with and without disabilities. Two common challenges for research in this area are that (1) There is a continuum of disabilities making it hard to optimize product features, and (2) There is no effective benchmark for evaluating such products. To exacerbate these issues, data regarding customer disabilities and their preferences is hard to come by. We propose a copula-based approach for modeling market coverage of a portfolio of universal products. The multiattribute preference of customers to purchase a product is modeled as Frank's Archimedean Copula. The inputs from various disparate sources can be collected and incorporated into a decision system.
2015-04-14
Technical Paper
2015-01-0606
Jiaquan Chen, Min Qin, Lingge Jin, Liu Tao, Yongfeng Jiang, Wei Wang, Yin-Ping Chang
Abstract An automotive vehicle should be designed to satisfy the wants of customers. The key is how to convert voices of customers into engineering languages. In other words, transfer the wants of customers into the right technical characteristics of a vehicle. A questionnaire of customer wants for a CUV (Crossover Utility Vehicle) is created and processed. Using QFD (Quality Function Deployment) and modified KANO model, the relative important degree is obtained from the original relative important degree of customer wants surveyed. Since some information gained is uncertain and the questionnaire sample is limited, a gray correlation analysis method is introduced, which calculates the competitive important degree of customer wants, then the final important degree of customer wants is gained by integrating the relative important degree and the competitive important degree.
2015-04-14
Technical Paper
2015-01-1588
Ibrahim A. Badiru, Michael W. Neal
Abstract Rapidly increasing customer, financial, and regulatory pressures are creating clear changes in the calculus of vehicle design for modern automotive OEM's (Original Equipment Manufacturers). Customers continue to demand shorter product lifecycles; the increasingly competitive global market exerts pressure to reduce costs in all stages of development; and environmental regulations drive a continuous need to reduce mass and energy consumption. OEM's must confront these challenges while continuing to satisfy the customer. The foundation to meeting these challenges includes: (1) Continued development of objective metrics to quantify performance; (2) Frontloading vehicle design content and performance synthesis; (3) A precise understanding of the customer and their performance preferences under diverse usage conditions. These combined elements will enable products better optimized amongst competing (and often contradictory) imperatives.
Viewing 241 to 270 of 5932