Terms:
SAE International Journal of Transportation Safety
AND
4
Show Only

Collections

File Formats

Content Types

Dates

Sectors

Topics

Authors

Publishers

Affiliations

Events

   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Pedestrian/Bicyclist Limb Motion Analysis from 110-Car TASI Video Data for Autonomous Emergency Braking Testing Surrogate Development

SAE International Journal of Transportation Safety

Indiana University Purdue University-Renran Tian, Stanley Chien, Li Fu, Yaobin Chen
TEMA-Rini Sherony
  • Journal Article
  • 2016-01-1456
Published 2016-04-05 by SAE International in United States
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. We modeled the pedestrian/bicyclist limb motions in four layers: (1) the percentages of pedestrians and bicyclists who have limb motions when crossing the road; (2) the averaged action…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Event Data Recorder (EDR) Developed by Toyota Motor Corporation

SAE International Journal of Transportation Safety

Bosch Automotive Service Solutions Inc.-William Rose
TEMA-Rini Sherony, Daniel Mikat
  • Journal Article
  • 2016-01-1495
Published 2016-04-05 by SAE International in United States
An event data recorder (EDR) records the vehicle status at the timing of an accident. Toyota Motor Corporation began the sequential introduction of EDRs onto its vehicles from August 2000. Currently, about 70% of all Toyota’s vehicles in North America are equipped with an EDR, which is more than the average rate of EDR installation in vehicles in North America (around 50%). The U.S. has introduced regulations for EDRs. Toyota regards these as minimum requirements and also records additional data for accident analysis, including the following: (1) pre-crash data, (2) side crash data, (3) rollover data, (4) pedestrian protection pop-up hood (PUH) data, and (5) vehicle control history (VCH) data from a non-crash triggered recording system. The regulations stipulate that EDR data retrieval must be possible using a commercially available tool. The developed system uses the Crash Data Retrieval (CDR) tool manufactured by Bosch. Data from all Toyota EDRs around the world can be retrieved using the CDR tool, including in North America. Since EDR data collection and analysis are very important for real-world accident…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

The Accuracy of an Optimized, Practical Close-Range Photogrammetry Method for Vehicular Modeling

SAE International Journal of Transportation Safety

Dial Engineering-Mu-Hua Cheng
Lightpoint Scientific, LLC-Louis R. Peck
  • Journal Article
  • 2016-01-1462
Published 2016-04-05 by SAE International in United States
Three targeted vehicles of varying size were measured using an optimized, practical photogrammetry technique and the results were compared to measurements acquired via total station. The photogrammetry method included the use of a field-calibrated DSLR camera equipped with a fixed 20 mm lens, retroreflective targets sized for vehicular modeling, and a CNC-machined scale bar. Eight photographs were taken from proper angles and processed using a commercially available photogrammetry package. This data was merged with the total station data using a cloud-to-cloud registration process for point-to-point comparison of positional data. The average residual between corresponding photogrammetry and total station points was 1.7 mm (N = 258, SD = 0.8 mm) with a 95% confidence limit of 3.1 mm. Considering this low residual, one of the sample vehicles was re-measured using a high accuracy FaroArm for comparison to the photogrammetry technique. The average residual between corresponding photogrammetry and FaroArm points was 1.2 mm (N = 83, SD = 0.56 mm) with a 95% confidence limit of 2.1 mm. This research shows photogrammetry can be highly accurate and…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Tire Mark Striations: Sensitivity and Uncertainty Analysis

SAE International Journal of Transportation Safety

Kineticorp LLC-Gray Beauchamp, Dana Thornton, William Bortles, Nathan Rose
  • Journal Article
  • 2016-01-1468
Published 2016-04-05 by SAE International in United States
Previous work demonstrated that the orientation of tire mark striations can be used to infer the braking actions of the driver [1]. An equation that related tire mark striation angle to longitudinal tire slip, the mathematical definition of braking, was presented. This equation can be used to quantify the driver’s braking input based on the physical evidence. Braking input levels will affect the speed of a yawing vehicle and quantifying the amount of braking can increase the accuracy of a speed analysis. When using this technique in practice, it is helpful to understand the sensitivity and uncertainties of the equation. The sensitivity and uncertainty of the equation are explored and presented in this study. The results help to formulate guidelines for the practical application of the method and expected accuracy under specified conditions. A case study is included that demonstrates the analysis of tire mark striations deposited during a real-world accident.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Influence of Pre-impact Pedestrian Posture on Lower Extremity Kinematics in Vehicle Collisions

SAE International Journal of Transportation Safety

Toyota Motor Corporation-Tsuyoshi Yasuki, Yuichi Kitagawa
Tsinghua University-Jisi Tang, Qing Zhou, Bingbing Nie
  • Journal Article
  • 2016-01-1507
Published 2016-04-05 by SAE International in United States
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. Pedestrian in walking posture exhibited larger knee bending angle (40% for ipsilateral knee joint) and pelvic rotation angle (27.5% for Z-direction pelvis rotation angle) with less constraint due to isolated single-leg interaction with vehicle and nonplanar characteristic from the leg swing. The walking posture increased the injury risk of soft connection tissue about 20-30%…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Forward Collision Warning: Clues to Optimal Timing of Advisory Warnings

SAE International Journal of Transportation Safety

University of Iowa-Lauren Sager, Sarah Hacker, Robert Marini, Jeffrey Dawson, Steven Anderson
University of Iowa Hospital and Clinic-Nazan Aksan
  • Journal Article
  • 2016-01-1439
Published 2016-04-05 by SAE International in United States
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. Closer inspection of data revealed that younger to middle aged drivers were already braking (42%) on…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Investigation of Driver Lane Keeping Behavior in Normal Driving based on Naturalistic Driving Study Data

SAE International Journal of Transportation Safety

TEMA-Rini Sherony
Virginia Tech.-Taylor Johnson, Rong Chen, Hampton C. Gabler
  • Journal Article
  • 2016-01-1449
Published 2016-04-05 by SAE International in United States
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. The study will be based upon data extracted from the Integrated Vehicle-Based Safety Systems (IVBSS) Naturalistic Driving…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Signal Sound Positioning Alters Driving Performance

SAE International Journal of Transportation Safety

Luleå University of Technology-André Lundkvist, Arne Nykänen, Roger Johnsson
  • Journal Article
  • 2015-01-9152
Published 2016-04-05 by SAE International in United States
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.
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Comparison of the Accuracy and Sensitivity of Generation 1, 2 and 3 Toyota Event Data Recorders in Low-Speed Collisions

SAE International Journal of Transportation Safety

MEA Forensic Engineers and Scientists-Peter Xing, Felix Lee, Thomas Flynn, Craig Wilkinson, Gunter Siegmund
  • Journal Article
  • 2016-01-1494
Published 2016-04-05 by SAE International in United States
The accuracy of the speed change reported by Generation 1 Toyota Corolla Event Data Recorders (EDR) in low-speed front and rear-end collisions has previously been studied. It was found that the EDRs underestimated speed change in frontal collisions and overestimated speed change in rear-end collisions. The source of the uncertainty was modeled using a threshold acceleration and bias model. This study compares the response of Generation 1, 2 and 3 Toyota EDRs from Toyota Corolla, Camry and Prius models. 19 Toyota airbag control modules (ACMs) were mounted on a linear sled. The ACMs underwent a series of frontal and rear-end haversine crash pulses of varying severity, duration and peak acceleration. The accuracy and trigger thresholds of the different models and generations of EDRs were compared. There were different accuracy trends found between the early Generation 1 and the more modern Generation 2 and 3 EDRs. There were also differences found in the threshold and trigger characteristics of the Generation 3 EDRs. This study extends the understanding of how Toyota EDRs respond in low speed collisions…
Annotation ability available
   This content is not included in your SAE MOBILUS subscription, or you are not logged in.

Fire Protection in Military Ground Vehicles

SAE International Journal of Transportation Safety

Alion Science and Technology-Steven E. Hodges
  • Journal Article
  • 2016-01-1404
Published 2016-04-05 by SAE International in United States
Fire protection, active and passive, has been, and is, an important area of concern during the design, development and deployment phases for all modern ground vehicles. All US military vehicles carry handheld fire extinguishers, and many tactical and all combat vehicles have automatic fire protection systems that protect the crew, engine, and in some cases, external components such as fuel tanks and wheels, from potentially catastrophic combat events involving fire. Vehicle designs also mitigate fire hazards by separating the vehicle occupants from the most flammable materials, e.g., fuel and ammunition, as much as practical. Explosion protection of the crew and passengers in military vehicles is a unique application with unique requirements that must balance suppression actions with safety limits. This paper presents an overview of general guidelines related to protecting military ground vehicle crews from injury due to fire, and lessons learned from the experiences of fielded systems.
Annotation ability available