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Viewing 211 to 240 of 5938
2016-04-05
Journal Article
2016-01-0462
Chunlei Wang, Xinjie Zhang, Konghui Guo, Fangwu Ma, Dong Chen
Abstract With the development of the advanced driver assistance system and autonomous vehicle techniques, a precise description of the driver’s steering behavior with mathematical models has attracted a great attention. However, the driver’s steering maneuver demonstrates the stochastic characteristic due to a series of complex and uncertain factors, such as the weather, road, and driver’s physiological and psychological limits, generating negative effects on the performance of the vehicle or the driver assistance system. Hence, this paper explores the stochastic characteristic of driver’s steering behavior and a novel steering controller considering this stochastic characteristic is proposed based on stochastic model predictive control (SMPC). Firstly, a search algorithm is derived to describe the driver’s road preview behavior.
2016-04-05
Journal Article
2016-01-0466
Daan Roethof, Tarik Sezer, Mustafa Ali Arat, Barys Shyrokau
Research of the past century has demonstrated that wheel camber regulation provides great potential to improve vehicle safety and performance. This led to the development of various prototypes of the camber mechanisms over the last decade. An overview of the existing prototypes is discussed in the presented paper. Most of the investigations related to camber control cover open-loop maneuvers to evaluate a vehicle response. However, a driver’s perception and his reaction can be the most critical factor during vehicle operation. Therefore, the research goal of the presented study is to assess an influence of active camber control on steering feel and driving performance using a driving simulator. In the proposed investigation, a dSPACE ASM vehicle model has been extended by introducing advanced models of steering system and active camber regulation. The steering system describes dynamics of steering components (upper and lower columns, torsion bar, steering rack and others).
2016-04-05
Journal Article
2016-01-0461
Wenfei Li, Haiping Du, Weihua Li
Abstract This paper proposes a new braking torque distribution strategy for electric vehicles equipped with a hybrid hydraulic braking and regenerative braking system. The braking torque distribution strategy is proposed based on the required braking torque and the regenerative braking system’s status. To get the required braking torque, a new strategy is designed based on the road conditions and driver's braking intentions. Through the estimated road surface, a robust wheel slip controller is designed to calculate the overall maximum braking torque required for the anti-lock braking system (ABS) under this road condition. Driver's braking intentions are classified as the emergency braking and the normal braking. In the case of emergency braking, the required braking torque is to be equal to the overall maximum braking torque. In the case of normal braking, the command braking torque is proportional to the pedal stroke.
2016-04-05
Journal Article
2016-01-1303
Haiqing Xu, Chang Jin, Hong Zhou, Yi Zhou
Abstract On the study of reducing the disturbance on driver’s attention induced by low frequency vehicle interior stationary noise, a subjective evaluation is firstly carried out by means of rank rating method which introduces Distraction Level (DL) as evaluation index. A visual-finger response test is developed to help evaluating members better recognize the Distraction Level during the evaluation. A non-linear back propagation artificial neural network (BPANN) is then modeled for the prediction of subjective Distraction Level, in which linear sound pressure RMS amplitudes of five Critical Band Rates (CBRs) from 20 to 500Hz are selected as inputs of the model. These inputs comprise an input vector of BPANN. Furthermore, active noise equalization (ANE) on DL is realized based on Filtered-x Least Mean Square (FxLMS) algorithm that controls the gain coefficients of inputs of trained BPANN.
2016-04-05
Journal Article
2016-01-1553
Akihito Yamamoto, Wataru Tanaka, Takafumi Makino, Shunya Tanaka, Ken Tahara
Abstract This paper reports that estimation accuracy of suspension stroke velocity is increased by considering the damping force delay characteristics to an observer. Thereby ride comfort is improved, using the simple and low-cost semi active suspension systems that use only three vertical acceleration sensors.
2016-04-05
Journal Article
2016-01-0084
Paul Weindorf, James Krier, Carl Evans
Abstract An optical configuration has been developed which offers a seamless appearance where the display aperture is less visible in the “off” condition and is minimized in the “on” condition.
2016-04-05
Journal Article
2016-01-0145
Madeleine Gibson, John Lee, Vindhya Venkatraman, Morgan Price, Jeffrey Lewis, Olivia Montgomery, Bilge Mutlu, Joshua Domeyer, James Foley
Abstract The rapid increase in the sophistication of vehicle automation demands development of evaluation protocols tuned to understanding driver-automation interaction. Driving simulators provide a safe and cost-efficient tool for studying driver-automation interaction, and this paper outlines general considerations for simulator-based evaluation protocols. Several challenges confront automation evaluation, including the limited utility of standard measures of driver performance (e.g., standard deviation of lane position), and the need to quantify underlying mental processes associated with situation awareness and trust. Implicitly or explicitly vehicle automation encourages drivers to disengage from driving and engage in other activities. Thus secondary tasks play an important role in both creating representative situations for automation use and misuse, as well as providing embedded measures of driver engagement.
2016-04-05
Journal Article
2016-01-1161
Akira Mori
Abstract In 2007, researchers at the Massachusetts Institute of Technology successfully completed a Wireless Power Transfer (WPT) experiment. Ever since, interest in WPT has been growing. At Toyota, we have been developing the underlying technology of a WPT system. Simultaneously we have been working with regulatory committees to create a standard for WPT. In particular, there are concerns that WPT’s radiated emissions could cause harm to humans and the neighboring electronic equipment. There are many challenges that need to be overcome, but a key concern is understanding WPT’s electromagnetic compatibility (EMI: Electro-Magnetic Interference and EMF: Electro-Magnetic Field). In this paper, we show the technical issues, the evaluation method, and the development status of EMI and EMF on PHVs/EVs when using WPT. For Electromagnetic interference (EMI) performance, we investigated both an open area test site and an electromagnetic anechoic chamber as evaluation environments.
2016-04-05
Journal Article
2015-01-9153
André Lundkvist, Arne Nykänen
Abstract The number of advanced driver assistance systems is constantly increasing. Many of the systems require visual attention, and a way to reduce risks associated with inattention could be to use multisensory signals. A driver's main attention is in front of the car, but inattention to surrounding areas beside and behind the car can be a risk. Therefore, there is a need for driver assistance systems capable of directing attention to the sides. In a simulator study, combined visual, auditory and vibrotactile signals for directional attention capture were designed for use in driver assistance systems, such as blind spot information, parking assistance, collision warnings, navigation, lane departure warning etc. An experiment was conducted in order to measure the effects of the use of different sensory modalities on directional attention (left/right) in driver assistance systems.
2016-04-05
Journal Article
2015-01-9152
André Lundkvist, Arne Nykänen, Roger Johnsson
Abstract Many of the information systems in cars require visual attention, and a way to reduce both visual and cognitive workload could be to use sound. An experiment was designed in order to determine how driving and secondary task performance is affected by the use of information sound signals and their spatial positions. The experiment was performed in a driving simulator utilizing Lane Change Task as a driving scenario in combination with the Surrogate Reference Task as a secondary task. Two different signal sounds with different spatial positions informed the driver when a lane change should be made and when a new secondary task was presented. Driving performance was significantly improved when both signal sounds were presented in front of the driver. No significant effects on secondary task performance were found. It is recommended that signal sounds are placed in front of the driver, when possible, if the goal is to draw attention forward.
2016-04-05
Journal Article
2016-01-1414
Shigeyoshi Hiratsuka, Shinichi Kojima, Nobuyuki Shiraki, Kazunori Higuchi, Toshihiko Tsukada, Keiichi Shimaoka, Kazuya Asaoka, Sho Masuda, Kazuhiko Nakashima
Abstract We investigated a lighting method that supports pedestrian perception by vehicle drivers. This lighting method makes active use of visual characteristics such as the spatio-temporal frequency of contrast sensitivity. Using reasonable parameter values derived from preliminary experiments using a Campbell-Robson chart, we determined a suitable lighting pattern that improves the driver's pedestrian perception. In order to assess the influence of visual characteristics on a reaction-time-dependent task, such as pedestrian perception in nighttime, tests were performed in the target environment, the results of which validated the proposed method.
2016-04-05
Journal Article
2016-01-1423
Richard Young, Sean Seaman, Li Hsieh
Abstract Many metrics have been used in an attempt to predict the effects of secondary tasks on driving behavior. Such metrics often give rise to seemingly paradoxical results, with one metric suggesting increased demand and another metric suggesting decreased demand for the same task. For example, for some tasks, drivers maintain their lane well yet detect events relatively poorly. For other tasks, drivers maintain their lane relatively poorly yet detect events relatively well. These seeming paradoxes are not time-accuracy trade-offs or experimental artifacts, because for other tasks, drivers do both well. The paradoxes are resolved if driver demand is modeled in two orthogonal dimensions rather than a single “driver workload” dimension. Principal components analysis (PCA) was applied to the published data from four simulator, track, and open road studies of visual-manual secondary task effects on driving.
2016-04-05
Journal Article
2016-01-1427
Richard Young, Li Hsieh, Sean Seaman
Abstract The Dimensional Model of Driver Demand is extended to include Auditory-Vocal (i.e., pure “voice” tasks), and Mixed-Mode tasks (i.e., a combination of Auditory-Vocal mode with visual-only, or with Visual-Manual modes). The extended model was validated with data from 24 participants using the 2014 Toyota Corolla infotainment system in a video-based surrogate driving venue. Twenty-two driver performance metrics were collected, including total eyes-off-road time (TEORT), mean single glance duration (MSGD), and proportion of long single glances (LGP). Other key metrics included response time (RT) and miss rate to a Tactile Detection Response Task (TDRT). The 22 metrics were simplified using Principal Component Analysis to two dimensions. The major dimension, explaining 60% of total variance, we interpret as the attentional effects of cognitive demand. The minor dimension, explaining 20% of total variance, we interpret as physical demand.
2016-04-05
Journal Article
2016-01-1439
Nazan Aksan, Lauren Sager, Sarah Hacker, Robert Marini, Jeffrey Dawson, Steven Anderson, Matthew Rizzo
Abstract We examined the effectiveness of a heads-up Forward Collision Warning (FCW) system in 39 younger to middle aged drivers (25-50, mean = 35 years) and 37 older drivers (66-87, mean = 77 years). The warnings were implemented in a fixed based, immersive, 180 degree forward field of view simulator. The FCW included a visual advisory component consisting of a red horizontal bar which flashed in the center screen of the simulator that was triggered at time-to-collision (TTC) 4 seconds. The bar roughly overlapped the rear bumper of the lead vehicle, just below the driver’s line-of-sight. A sustained auditory tone (∼80 dB) was activated at TTC=2 to alert the driver to an imminent collision. Hence, the warning system differed from the industry standard in significant ways. 95% Confidence intervals for the safety gains ranged from -.03 to .19 seconds in terms of average correction time across several activations. Older and younger adults did not differ in terms of safety gains.
2016-04-05
Journal Article
2016-01-1449
Taylor Johnson, Rong Chen, Rini Sherony, Hampton C. Gabler
Abstract Lane departure warning (LDW) systems can detect an impending road departure and deliver an alert to allow the driver to steer back to the lane. LDW has great potential to reduce the number of road departure crashes, but the effectiveness is highly dependent upon driver acceptance. If the driver perceives there is little danger after receiving an alert, the driver may become annoyed and deactivate the system. Most current LDW systems rely heavily upon distance to lane boundary (DTLB) in the decision to deliver an alert. There is early evidence that in normal driving DTLB may be only one of a host of other cues which drivers use in lane keeping and in their perception of lane departure risk. A more effective threshold for LDW could potentially be delivered if there was a better understanding of this normal lane keeping behavior. The objective of this paper is to investigate the lane keeping behavior of drivers in normal driving.
2016-04-05
Journal Article
2016-01-1456
Rini Sherony, Renran Tian, Stanley Chien, Li Fu, Yaobin Chen, Hiroyuki Takahashi
Abstract Many vehicles are currently equipped with active safety systems that can detect vulnerable road users like pedestrians and bicyclists, to mitigate associated conflicts with vehicles. With the advancements in technologies and algorithms, detailed motions of these targets, especially the limb motions, are being considered for improving the efficiency and reliability of object detection. Thus, it becomes important to understand these limb motions to support the design and evaluation of many vehicular safety systems. However in current literature, there is no agreement being reached on whether or not and how often these limbs move, especially at the most critical moments for potential crashes. In this study, a total of 832 pedestrian walking or cyclist biking cases were randomly selected from one large-scale naturalistic driving database containing 480,000 video segments with a total size of 94TB, and then the 832 video clips were analyzed focusing on their limb motions.
2016-04-05
Journal Article
2016-01-1507
Jisi Tang, Qing Zhou, Bingbing Nie, Tsuyoshi Yasuki, Yuichi Kitagawa
Abstract Lower extremities are the most frequently injured body regions in vehicle-to-pedestrian collisions and such injuries usually lead to long-term loss of health or permanent disability. However, influence of pre-impact posture on the resultant impact response has not been understood well. This study aims to investigate the effects of preimpact pedestrian posture on the loading and the kinematics of the lower extremity when struck laterally by vehicle. THUMS pedestrian model was modified to consider both standing and mid-stance walking postures. Impact simulations were conducted under three severities, including 25, 33 and 40 kph impact for both postures. Global kinematics of pedestrian was studied. Rotation of the knee joint about the three axes was calculated and pelvic translational and rotational motions were analyzed.
2016-04-05
Journal Article
2016-01-1540
Timothy Keon
Abstract The National Highway Traffic Safety Administration has performed research investigating the Test Device for Human Occupant Restraint 50th male (THOR-50M) response in Oblique crash tests. This research is being expanded to investigate THOR-50M in the driver position in a 56 km/h frontal impact crash. Hybrid III 5th percentile adult female (AF05) anthropomorphic test devices (ATDs) were used in this testing to evaluate the RibEye Deflection Measurement System. The AF05 ATDs were positioned in the right front passenger and right rear passenger seating positions. For the right front passenger, the New Car Assessment Procedure (NCAP) seating procedure was used, except the seat fore-aft position was set to mid-track. For the right rear passenger, the seating followed the FMVSS No. 214 Side Impact Compliance Test Procedure. The NCAP frontal impact test procedure was followed with additional vehicle instrumentation and pre/post-test measurements.
2016-04-05
Journal Article
2016-01-1526
Daniel V. McGehee, Cheryl A. Roe, Linda Ng Boyle, Yuqing Wu, Kazutoshi Ebe, James Foley, Linda Angell
Abstract Pedal misapplications may be rare, but the outcomes can be tragic. A naturalistic driving study with 30 drivers was conducted to gain a better understanding of foot pedal behaviors. Foot movements were observed from the moment subjects entered and positioned themselves in their vehicle, and continued through starting the ignition, shifting into gear, accelerating to driving speed, and finally, resting their foot after parking the vehicle. A coding methodology was developed to categorize the various foot movements and behaviors. Over 3,300 startup and parking sequences were coded. This paper describes the unique challenges involved in classifying foot movements and behaviors when drivers’ intentions are not known. For example, hesitant or interrupted foot movements often occurred when a driver was transitioning from a gas pedal press to a brake pedal press.
2016-04-05
Technical Paper
2016-01-1530
Yury Chudnovsky, Justin Stocks-Smith, Jeya Padmanaban, Joe Marsh
Abstract NASS/CDS data (1993-2013) was used to examine serious injury rates and injury sources for belted drivers in near- and far-side impacts. Frequency and severity of near- and far-side impacts by crash severity (delta-V) were compared for older (1994-2007 MY) and newer (2008-2013 MY) vehicles. For 2008-2013 MY, individual cases were examined for serious thorax injury in far-side impacts. Results show that, for newer passenger cars, about 92% of side impacts have a delta-V under 15 mph and, for older cars, the percentage is about 86%. The rate of serious injury is higher for nearside compared to far-side crashes for both older and newer models, and the near-side injury rate is much lower for newer models. Safety features, including side airbags, are effective in reducing injuries to near-side belted drivers in newer models. The serious injury rate for near-side belted drivers in older cars is 5.5% for near-side crashes and 1.2% for far-side crashes.
2016-04-05
Journal Article
2016-01-1486
Qi Zhang, Bronislaw Gepner, Jacek Toczyski, Jason Kerrigan
Abstract While over 30% of US occupant fatalities occur in rollover crashes, no dummy has been developed for such a condition. Currently, an efficient, cost-effective methodology is being implemented to develop a biofidelic rollover dummy. Instead of designing a rollover dummy from scratch, this methodology identifies a baseline dummy and modifies it to improve its response in a rollover crash. Using computational models of the baseline dummy, including both multibody (MB) and finite element (FE) models, the dummy’s structure is continually modified until its response is aligned (using BioRank/CORA metric) with biofidelity targets. A previous study (Part I) identified the THOR dummy as a suitable baseline dummy by comparing the kinematic responses of six existing dummies with PMHS response corridors through laboratory rollover testing.
2016-03-27
Technical Paper
2016-01-1738
Natt Winitthumkul, Peerapat Phondeenana, Nuksit Noomwongs
Abstract According to the recent study, Thailand has the 2nd most dangerous road in the world. Based on many researches, the driver is the main influencers of the traffic fatalities. Since the more dangerous the driver drive, the more chance of accident become. Therefore, driver’s monitoring system become one of the solutions that acceptable and reliable, especially for fleet management and public transportation. This paper’s goal is to find an algorithm that can distinguish driving behaviour based on cars’ acceleration and velocity, calling it as Risk Driving Score (RDS). The algorithm was tested by driving test by volunteers on highways with observers, who were told to rank the drivers in terms of driving risk from the 1-5 point. Meanwhile, the drivers were asked to drive in 3 different styles, normal, safety, and hurry. All drives were recorded by satellite and video data then filtered and used for the algorithm calculation.
2016-03-27
Technical Paper
2016-01-1737
Thitsadee Ngernsukphaiboon, Sunhapos Chantranuwathana, Nuksit Noomwongs, Angkee Sripakagorn, Solaphat Hemrungrojn MD
Abstract The world is aging rapidly. Many countries can already be categorized as aging or aged societies while a few are becoming super-aged societies. In Thailand as well as in other countries, traffic accidents caused by elderly drivers will continue to rise as a significant percentage of elderly people still prefer to drive. Accidents may be prevented with driving tests and screening methods for elderly drivers. However, it is also necessary to understand the effect of aging on driving ability. With this understanding, driver training, driver assistant systems, and improvements on infrastructure may be designed accordingly. Among various physical changes, cognitive ability of the brain is one of the most significant factors affecting driving ability. In this paper, correlation between various cognitive functions of the brain and car following skill of drivers are considered.
2016-02-01
Technical Paper
2016-28-0044
Ashish Rawat, Ashwinder Singh, Hardeep Singh, Deepak Sharma
Abstract India is a country of diversity. From North to South, east to west, one can find altogether different culture, religions, spoken languages, foods, weather conditions, people lifestyles, dressing styles etc. This vast diversity of India poses a great challenge in front of Indian Automobile Manufacturers, so as to assimilate all the requirements (of this big nation) in one single car (design). For example, many people in India wear turban (out of their religious beliefs or cultural heritage). So, is it required to keep enough consideration for Turban wearing population in vehicle design? Turban, unlike caps or hats, is something which is tied on the head (not just only kept). It is something which cannot be removed whenever required. So, it can somehow be considered as an integral part of body (as an added head dimension). So, it becomes all the more important to thoroughly understand this aspect & keep a consideration for the same in vehicle design.
2016-02-01
Technical Paper
2016-28-0233
Sindhu Ls, Vishwas Vaidya
Abstract The OEM's aim is to reduce development time and testing cost, hence the objective behind this work is to achieve a flexible stateflow model so that changes in the application during supply chain or development, on adding/deleting any switches, varying timer cycle, changing the logic for future advancements or else using the logic in different application, would end in minimal changes in the chart or in its states which would reflect least changes in the code. This research is about designing state machine architecture for chime/buzzer warning system and wiper/washer motor control system. The chime/buzzer stateflow chart includes various input switches like ignition, parking, seat belt buckle, driver door and speed accompanied with warning in the form of LED, lamp and buzzer. The logic is differentiated according to gentle and strong warning. Various conditions and scenarios of the vehicle and driver are considered for driver door and seat belt which is resolved in the chart.
2016-02-01
Technical Paper
2016-28-0236
Manish Kumar, Jasbir Singh, Vikram Khanna
Abstract In the Indian Context, Fuel Economy of a vehicle is one of key elements while buying a Car. The fuel economy declared by OEMs (Original Equipment Manufacturers) is one of the key indicators while assessing the fuel economy. However it is based on a standard driving cycle and evaluated under standard conditions as mandated by emission legislation. As the driving pattern has a major influence on fuel economy, the objective of this paper is to study real world driving patterns and to define a methodology to simulate a real world driving cycle. A case study was done on Delhi City, by running a fleet of vehicles in different traffic conditions. Thereafter data analysis like acceleration %, specific energy demand per distance, Acceleration vs. Vehicle Speed distribution etc. was done with the help of MATLAB. The final validation of cycle was done by comparing Lab results with on-road Fuel Economy data.
2016-02-01
Technical Paper
2016-28-0223
Aneesh Paul, Rohan Chauhan, Rituraj Srivastava, Mriganka Baruah
This paper provides a detailed study of the recent developments in the field of Advanced Driver Assistance Systems and researches in ADASs since last decade. The paper provides a survey on Cognitive cars and driver oriented intelligent vehicles and their motion, stimuli, reflex and response. The main objectives of the paper re the future advancements in ADASs, the response duration, user-compatibility and stimuli decision-action on driver as well as on the system side. "THE SOUL PURPOSE OF ADASs IS TO SUPPORT THE DRIVERS RATHER THAN TO REPLACE THEM". Keeping this into consideration, this paper addresses the major achievements and major difficulties in making Advanced Driver Assistance System to be incorporated in today’s automation. The paper describes the pros and cons on the modern day cognitive cars, its areas of improvement and further modifications. The paper also describes briefly about the driver safety when the ADASs is not implemented and modern day driving skills.
2016-02-01
Technical Paper
2016-28-0251
Kantilal Patil, Siva Reddy, Nadeem Zafar
Abstract In the event of a frontal car crash, occupant sitting in a car meets various types of injuries like Head injury, Chest compression, Neck injury etc. These injuries may lead to the death of an occupant if exceeded beyond biomechanical limits. Seat belt is a primary restraint system, which when worn controls the motion of occupant sitting inside the car during the event of a car crash. An Anchorage location of three point seat belt system has significant effect on occupant injuries during the crash event. By changing the mount locations of a seat belt anchor points i.e. D-ring, Anchor & Buckle, performance of seatbelt system can be enhanced further thereby reducing occupant injuries to certain extent. As per regulation AIS015, locations of safety belt anchorage points should be within prescribed zone.
2015-11-17
Technical Paper
2015-32-0705
Takanobu Fujimura
Due to environmental problems, number of small vehicles with fuel efficiency increases. Since the small vehicles have small deformation space, it is difficult for them to achieve good crashworthiness at a frontal impact accident. Small deformation space usually yields high vehicle deceleration to absorb kinetic energy of the vehicle. The high vehicle deceleration may produce high occupant deceleration and lead to high occupant injury value. For example, North America, Japan and Europe specify head and chest injury value at vehicle's frontal collision. Those injury values tend to be improved if vehicle deceleration decreases. Deceleration of small vehicle with a little deformation space must be adjusted in order to prevent increase of the occupant injury value. A vehicle deceleration is expressed by 9, 18 or 36 discrete variables. A vehicle, an occupant and restraint systems such as seat belts are modeled by masses and a spring to simulate a frontal collision.
2015-11-09
Technical Paper
2015-22-0009
Meghan K. Howes, Warren N. Hardy, Amanda M. Agnew, Jason J. Hallman
High-speed biplane x-ray was used to research the kinematics of the small intestine in response to seatbelt loading. Six driver-side 3-point seatbelt simulations were conducted with the lap belt routed superior to the pelvis of six unembalmed human cadavers. Testing was conducted with each cadaver perfused, ventilated, and positioned in a fixed-back configuration with the spine angled 30° from the vertical axis. Four tests were conducted with the cadavers in an inverted position, and two tests were conducted with the cadavers upright. The jejunum was instrumented with radiopaque markers using a minimally-invasive, intraluminal approach without inducing preparation-related damage to the small intestine. Tests were conducted at a target peak lap belt speed of 3 m/s, resulting in peak lap belt loads ranging from 5.4-7.9 kN. Displacement of the radiopaque markers was recorded using high-speed x-ray from two perspectives.
Viewing 211 to 240 of 5938