scholarly journals Drivers’ Braking Behaviors in Different Motion Patterns of Vehicle-Bicycle Conflicts

2019 ◽  
Vol 2019 ◽  
pp. 1-17 ◽  
Author(s):  
Lian Hou ◽  
Jingliang Duan ◽  
Wenjun Wang ◽  
Renjie Li ◽  
Guofa Li ◽  
...  
Keyword(s):  
Driving Simulator ◽  
Orthogonal Experiment ◽  
Lateral Velocity ◽  
Motion Patterns ◽  
Time To Collision ◽  
The Road ◽  
Emergency Braking ◽  
Lower Expectation ◽  
Tracking Device ◽  
Conflict Types

Bicycling is one of the popular modes of transportation, but bicyclists are easily involved in injuries or fatalities in vehicle-bicycle (V-B) accidents. The AEB (Autonomous Emergency Braking) systems have been developed to avoid collisions, but their adaptiveness needs to be further improved under different motion patterns of V-B conflicts. This paper analyzes drivers’ braking behaviors in different motion patterns of V-B conflicts to improve the performance of Bicyclist-AEB systems. For safety and data reliability, a driving simulator was used to reconstruct two typical conflict types, i.e., SCR (a bicycle crossing the road from right in front of a straight going car) and SSR (a bicycle cut-in from right in front of a straight going car). Either conflict contained various parameterized motion patterns, which were characterized by a combination of parameters: Vc (car velocity), TTC (time-to-collision), Vb (bicycle velocity), and Dlat (lateral distance between the car and the bicycle) or Vlat (maximum lateral velocity of the bicycle). Some 26 licensed drivers participated in an orthogonal experiment for braking behavior analysis. Results revealed that drivers brake immediately when V-B conflicts occur; hence the BRT (brake reaction time) is independent of any motion pattern parameters. This was further verified by another orthogonal experiment with 10 participants using the eye tracking device. BRT in SSR is longer than that in SCR due to the less perceptible risk and drivers’ lower expectation of a collision. The braking intensity and brake Pedal Speed are higher in short-TTC patterns in both conflict types. Therefore, TTC is not a proper activation threshold but a reasonable indicator of braking intensity and Pedal Speed for driver-adaptive AEB systems. By applying the findings in the Bicyclist-AEB, the adaptiveness and acceptability of Bicyclist-AEB systems can be improved.

Effects of Visually Induced Motion Sickness on Emergency Braking Reaction Times in a Driving Simulator

2019 ◽  
Vol 61 (6) ◽  
pp. 1004-1018
Author(s):  
René Reinhard ◽  
Ender Tutulmaz ◽  
Hans M. Rutrecht ◽  
Patricia Hengstenberg ◽  
Britta Geissler ◽  
...  
Keyword(s):  
Motion Sickness ◽  
Mixed Model ◽  
Driving Simulator ◽  
Reaction Times ◽  
Visually Induced Motion Sickness ◽  
The Road ◽  
Emergency Braking ◽  
Fixed Base ◽  
Induced Motion ◽  
Relationship Of

Objective: The study explores associations of visually induced motion sickness (VIMS) with emergency braking reaction times (RTs) in driving simulator studies. It examines the effects over the progression of multiple simulated drives. Background: Driving simulator usage has many advantages for RT studies; however, if it induces VIMS, the observed driving behavior might deviate from real-world driving, potentially masking or skewing results. Possible effects of VIMS on RT have long been entertained, but the progression of VIMS across simulated drives has so far not been sufficiently considered. Method: Twenty-eight adults completed six drives on 2 days in a fixed-base driving simulator. At five points during each drive, pedestrians entered the road, necessitating emergency braking maneuvers. VIMS severity was assessed every minute using the 20-point Fast Motion Sickness Scale. The progression of VIMS was considered in mixed model analyses. Results: RT predictions were improved by considering VIMS development over time. Here, the relationship of VIMS and RT differed across days and drives. Increases in VIMS symptom severity predicted more prolonged RT after repeated drives on a given day and earlier within each drive. Conclusion: The assessment of VIMS in RT studies can be beneficial. In this context, VIMS measurements in close temporal proximity to the behaviors under study are promising and offer insights into VIMS and its consequences, which are not readily obtainable through questionnaires. Application: Driving simulator–based RT studies should consider cumulative effects of VIMS on performance. Measurement and analysis strategies that consider the time-varying nature of VIMS are recommended.

scholarly journals Research on Virtual Test of Automobile Automatic Emergency Braking System on Ice-Snow Road

2021 ◽  
Vol 261 ◽  
pp. 02065
Author(s):  
Xianchao Zhu ◽  
Sheng Chang ◽  
Bingtao Li ◽  
Hualei Lu
Keyword(s):  
Weather Conditions ◽  
Simulation Method ◽  
Time To Collision ◽  
The Road ◽  
Injury Reduction ◽  
Emergency Braking ◽  
Virtual Test ◽  
Braking Distance ◽  
On The Road ◽  
Basic Characteristics

In view of the severe weather conditions in cold regions, the basic characteristics and braking distance of ice snow covered pavement are analyzed. This paper uses the PreScan/CarSim/Simulink software co-simulation method to test the automatic emergency braking (AEB) system on ice-snow roads. Through the appropriate adjustment of the time to collision (TTC) threshold, the car makes automatic emergency braking on the road with low friction coefficient system can achieve the effect of collision avoidance and injury reduction.

Benefits of Redundant Visual In-Vehicle Information in Pedestrian–Vehicle Conflict Scenarios

2019 ◽  
Vol 2673 (9) ◽  
pp. 674-683
Author(s):  
Liberty Hoekstra-Atwood ◽  
Connor Hoover ◽  
Christian M. Richard
Keyword(s):  
Driving Simulator ◽  
Pedestrian Safety ◽  
Conflict Situation ◽  
Minimum Time ◽  
Baseline Condition ◽  
Time To Collision ◽  
Driver Response ◽  
The Road ◽  
Vehicle Information ◽  
Safety Systems

The paper provides information relevant to the development of driver and pedestrian safety systems by examining drivers’ responses to infrastructure-based safety messages (DII) with a redundant in-vehicle display component. A driving simulator was used to create a conflict situation which required an immediate driver response to avoid a collision. At the start of the event, a pedestrian was occluded by a truck at an intersection. Partway through the event, the pedestrian dashed into the road and into the driver’s path. When redundant visual in-vehicle alerting messages were provided, drivers released the throttle more quickly, engaged the brake more quickly, and had longer minimum time to collision relative to the baseline condition which lacked visual alerts. This was an improvement over the DII-only condition, where drivers did not brake more quickly relative to baseline and had only marginally longer minimum time to collision compared with the baseline condition. The findings suggest that redundant in-vehicle message information provides a benefit to many drivers over systems that use only infrastructure-based safety systems in vehicle–pedestrian conflicts.

Left or Right: Auditory Collision Warnings for Driving Assistance Systems

2017 ◽  
Vol 61 (1) ◽  
pp. 1551-1551 ◽  
Author(s):  
Edin Sabic ◽  
Jing Chen
Keyword(s):  
Decision Making ◽  
Driving Simulator ◽  
Steering Wheel ◽  
Warning Systems ◽  
Collision Warning ◽  
Time To Collision ◽  
The Road ◽  
Driving Scenario ◽  
Assistance Systems ◽  
The Impact

Assistance driving systems aim to facilitate human behavior and increase safety on the road. These systems comprise common systems such as forward collision warning systems, lane deviation warning systems, and even park assistance systems. Warning systems can communicate with the driver through various modalities, but auditory warnings have the advantage of not further tasking visual resources that are primarily used for driving. Auditory warnings can also be presented from a certain location within the cab environment to be used by the driver as a cue. Beattie, Baillie, Halvey, and McCall (2014) assessed presenting warnings in stereo configuration, coming from one source, and bilateral configuration, panned fully from left or right, and found that drivers felt more in control with lateral warnings than stereo warnings when the car was in self-driving mode. Straughn, Gray, and Tan (2009) examined laterally presented auditory warnings to signal potential collisions. They found that the ideal presentation of warnings in either the avoidance direction, in which the driver should direct the car to avoid a collision, or the collision direction, in which the potential collision is located, was dependent on time to collision. Wang, Proctor, and Pick (2003) applied the stimulus-response compatibility principle to auditory warning design by using a steering wheel in a non-driving scenario and found that a tone presented monaurally in the avoidance-direction led to the fastest steering response. However, the reverse finding occurred when similar experiments utilized a driving simulator in a driving scenario (Straughn et al., 2009; Wang, Pick, Proctor, & Ye, 2007). The present study further investigated how to design spatially presented auditory collision warnings to facilitate drivers’ response to potential collisions. Specifically, tones indicating a pedestrian walking across the road were presented either in the avoidance direction or in the collision direction. The experimental task consisted of monitoring the road for potential collisions and turning the wheel in the appropriate direction to respond. Additionally, time to collision was manipulated to investigate the impact of the timing of the warning and increasing time pressure on the steering response. Time to collision was manipulated by half second intervals from two to four seconds resulting in five different time-to-collision scenarios. Lastly, the effect of individual differences in decision-making styles were also considered by using two decision-making style questionnaires. Results from the experiment showed that the presentation of a collision warning in the collision direction led to faster responses when compared to the warning in the avoidance direction. This result may be due to the collision warning directing the attention of the participant to the location of the threat so that they can more quickly make a response decision. Further, the advantage of avoidance-direction warnings over collision-direction warnings was greater with greater time to collision. Results showed that participant responses to varying time to collision influenced their reaction time. The participants appeared to have not relied solely on the auditory tones, but rather they utilized the warning tones in conjunction with visual information in the environment. These results from this study have implications for improving collision avoidance systems: Presentation of a collision warning in the direction of the collision may be more intuitive to drivers, regardless of time to collision.

Improved AEB algorithm combined with estimating the adhesion coefficient of road ahead and considering the performance of EHB

2021 ◽  
pp. 095440702110261
Author(s):  
Dequan Zeng ◽  
Zhuoping Yu ◽  
Lu Xiong ◽  
Junqiao Zhao ◽  
Peizhi Zhang ◽  
...  
Keyword(s):  
Joint Probability ◽  
Principal Component ◽  
Test Results ◽  
Safe Distance ◽  
Adhesion Coefficient ◽  
The Road ◽  
Response Characteristics ◽  
Emergency Braking ◽  
Multiple Beams ◽  
Maximum Method

This paper proposes an improved autonomous emergency braking (AEB) algorithm intended for intelligent vehicle. Featuring a combination with the estimation of road adhesion coefficient, the proposed approach takes into account the performance of electronic hydraulic brake. In order for the accurate yet fast estimate of road ahead adhesion coefficient, the expectation maximization framework is applied depending on the reflectivity of ground extracted by multiple beams lidar in four major steps, which are the rough extraction of ground points based on 3 σ criterion, the accurate extraction of ground points through principal component analysis (PCA), the main distribution characteristics of ground as extracted using the expectation maximum method (EM) and the estimation of road adhesion coefficient via joint probability. In order to describe the performance of EHB, the response characteristics, as well as the forward and adverse models of both braking pressure and acceleration are obtained. Then, with two typical roads including single homogeneous road and fragment pavement, the safe distance of improved AEB is modeled. To validate the algorithm developed in this paper, various tests have been conducted. According to the test results, the reflectivity of laser point cloud is effective in estimating the road adhesion coefficient. Moreover, considering the performance of EHB system, the improved AEB algorithm is deemed more consistent with the practicalities.

Driver Performance in a Cooperative Adaptive Cruise Control String

2016 ◽  
Vol 60 (1) ◽  
pp. 1184-1188 ◽  
Author(s):  
Vaughan W. Inman ◽  
Steven Jackson ◽  
Brian H. Philips
Keyword(s):  
Adaptive Cruise Control ◽  
Driving Simulator ◽  
Cruise Control ◽  
Highway Capacity ◽  
Time To Collision ◽  
Driver Performance ◽  
Cooperative Adaptive Cruise Control ◽  
Safety Benefit ◽  
Crash Reduction ◽  
Mean Time

Cooperative Adaptive Cruise Control (CACC) has been proposed as a method to increase highway capacity and possibly enhance safety. Two experiments were conducted in a driving simulator to verify that drivers with CACC would effectively monitor the system’s longitudinal control and override the system in the event that greater braking authority was needed than the system was designed to provide. In the first experiment, the emergency response of drivers with the CACC was compared with that of drivers who manually controlled following distance within a string of vehicles. The CACC group experienced markedly fewer crashes and had longer mean time-to-collision. The second experiment examined whether the CACC safety benefit was the result of the CACC system’s limited automatic braking authority, an auditory alarm, or both. The results suggest that both auto-braking and an auditory alarm are necessary to achieve a crash reduction benefit, although the alarm alone may promote less severe collisions.

Advance Information on the Road: A Simulator Study of the Effect of Road Markings

1976 ◽  
Vol 18 (6) ◽  
pp. 521-532 ◽  
Author(s):  
Harald Witt ◽  
Carl G. Hoyos
Keyword(s):  
Driving Simulator ◽  
Driving Behavior ◽  
Speed Profile ◽  
The Road ◽  
Positive Effects ◽  
Road Signs ◽  
Advance Information ◽  
Simulator Study ◽  
On The Road ◽  
Accident Statistics

Accident statistics and studies of driving behavior have shown repeatedly that curved roads are hazardous. It was hypothesized that the safety of curves could be improved by indicating in advance the course of the road in a more effective way than do traditional road signs. A code of sequences of stripes put on right edge of the pavement was developed to indicate to the driver the radius of the curve ahead. The main characteristic of this code was the frequency of transitions from code elements to gaps between elements. The effect of these markings was investigated on a driving simulator. Twelve subjects drove on simulated roads of different curvature and with different placement of the code in the approach zone. Some positive effects of the advance information could be observed. The subjects drove more steadily, more precisely, and with a more suitable speed profile.

Good Intentions? Willingness to Engage with Technology on the Road and in a Driving Simulator

2018 ◽  
pp. 147-176 ◽  
Author(s):  
Katie J. Parnell ◽  
Neville A. Stanton ◽  
Katherine L. Plant
Keyword(s):  
Driving Simulator ◽  
The Road ◽  
On The Road ◽  
Willingness To Engage

scholarly journals Simulation Study of the Process of Friction in the Working Elements of a Car Braking System at Different Degrees of Wear

2018 ◽  
Vol 12 (3) ◽  
pp. 221-226 ◽  
Author(s):  
Andrzej Borawski
Keyword(s):  
Simulation Study ◽  
Friction Pair ◽  
Experimental Studies ◽  
Real Life ◽  
Operating Conditions ◽  
Heating Process ◽  
Passenger Cars ◽  
The Road ◽  
Emergency Braking ◽  
Braking System

Abstract Among the many elements of a modern vehicle, the braking system is definitely among the most important ones. Health, and, frequently, life, may rest upon the design and reliability of brakes. The most common friction pair used in passenger cars today is a disc which rotates with the road wheel and a cooperating pair of brake pads. The composite material of the pad results in changing tribological properties as the pad wears, which was demonstrated in experimental studies. The change is also facilitated by the harsh operating conditions of brakes (high and rapid temperature changes, water, etc.). This paper looks into how changing tribology reflects on the heating process of disc and pads during braking. And so a simulation study was conducted, as this method makes it possible to measure temperature in any given point and at any time, which is either impossible or extremely difficult in real life conditions. Finite element method analyses were performed for emergency braking events at various initial speeds of the vehicle reflecting the current road speed limits.

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