(1) Experimental Verification of the Relationship between
Pedal-to-Pedal Distance and Pedal Misapplication(2) Detection of Distress Caused by Pedal Misapplication
and Its Application to Accident Prevention Systems
Kentaro Kotani (Faculty of Engineering Science, Kansai University)
Takafumi Asao (Faculty of Engineering Science, Kansai University)
Jun Arakawa (Faculty of Engineering Science, Kansai University)
Yasunori Watanabe (Faculty of Engineering Science, Kansai University)

Overview• Experimental verification was conducted in this study concerning the separation
between the accelerator and brake pedals and bodily reaction in the event that adriver feels distressed, which are among the factors causing pedal misapplication.
• With regard to the effects of pedal separation, we investigated whether theinteraction between the driver’s body height and pedal separation that has beenreported by the NHTSA can be shown experimentally. As a result, it was observedthat the error rate tends to change more for taller drivers than for shorter drivers.
• In addition, we attempted to detect reflexive eye blinking as an index for detecting
pedal misapplication when the driver felt distressed due to video and audio whiledriving, and experimentally investigated whether reflexive eye blinking can besignificantly detected depending on whether the driver was distressed. As a result,blinking of short latency such as that described in previous studies could not bedetected, but it was observed that the average latency of blinking when the driver
was subjectively distressed tended to decrease.

(1) Experimental Verification of the Relationship between Pedal-toPedal Distance and Pedal Misapplication

Problems with Pedal Design• The layout of pedals and their shapes are different depending on
various automobile companies (Furuya et al., 2010)• It is necessary to examine the layout of pedals in order to prevent
pedal misapplication (Nihei, 2000)

However

Pedals are not being designed with theprevention of pedal misapplication taken into
consideration.

Because investigations into accidents have suggested the relationship between pedal separation in the horizontal direction and pedal
misapplication (Collins, et al., 2015), a survey was conducted on variations in the distance between pedals in the horizontal direction.
Results of surveying 16 models50 [mm] – 150 [mm]There is a large variation in the distance between pedals on automobiles.

Purpose of the experiments
To verify the relationship between pedal separation and pedal misapplication
through experimentation

Description of the ExperimentParticipants in the experiment
14 male college students between the ages of 22 and 24 with driving experience

Experimental environment
MonitorExperiment participant

Conditions of the experiment
Five levels in the distance between pedals in the horizontal direction (30 mm to150 mm)～Distance between pedals: 30 mm

Distance between pedals: 150 mm

Task that induces pedal misapplication
Inhibition task
Used for evaluating the inhibition function, which is a function
for inhibiting inappropriate actions or motor reactions+Automobile driving actions

When ● is displayed, step When ● is displayed, stepon the brakeon the accelerator

Reverse reaction if a sound isheard

Results of the Experiment
Previous studies (Collins, et al., 2015)
The wider the distance between the pedals in the horizontal direction, the more likely that pedal misapplication will occur among drivers who are 168
cm or taller.
The probability of pedal misapplication occurring among drivers who are less than 168 cm tall remains the same regardless of the distance between
the pedals in the horizontal direction.
Height of 168 cm more

Error rate [%]Height of less than 168 cm

Results of the Experiment
Subjects who are 168 cm or taller
Opposite tendency compared to previous studies
Perhaps the narrowness of thedriver's seat may have significantly
impacted the error rate.

Conclusion
Changes in the distance between
pedals affect the driver’s performancein some way.
Distance between pedals [mm]Point requiring improvement

Problem in this experiment•Significant difference from the actual
driving environment

Point requiring improvement
Conduct the experiment under an experiment systemthat is close to the actual driving environment⇒ Enlarging the driver's seat and providing a sense ofoperating a car•

Future Outlook•

Carry out large-scale investigations into pedal-to-pedal distance•

Conduct experiments with pedal-to-pedal distances that were not added to theexperiment conditions for this experiment•

In addition to pedal-to-pedal distance, the height, shape, and size of the pedals will
also be studied.

(2) Detection of Shock Caused by Pedal Misapplication and Its
Application to Accident Prevention Systems

Detection of Distress Caused by Pedal Misapplication and Its Application toAccident Prevention Systems
Distress felt by the driver will lead to traffic accidents (pedalmisapplication)
Many drivers who drive inappropriately fall into panic (becomedistressed) in order to evade danger, thus leading to accidents(ITARDA Information, 2014).
Is it possible to reduce accidents by detecting distress in drivers?
Method of detecting distress…
Focusing on reflexive eye blinking reaction
Characteristics:
Appears the fastest among human defensive reflexes (Yamada, 2002)
Brought about by clear external stimuli (Fukuda et al., 2015)

Pedal misapplication

Passed through as usual
Absent-minded, vague
Distressed, was in a hurry
Rushing, panicking
Was drinking
Paying attention to other things, distracted
Car that one is not familiar with
Lack of driving skills/experience, overconfidence
Clothes/shoes inappropriate for driving
Old age

Number of respondents (persons)Will it be possible through experimentation to observe through blinking information that the driver becomes startled at thetime of pedal misapplication (momentarily surprised and panicking, and subsequently shifting to a state of distress with thepassage of time)…

Overview of Blink Detection Experiment
Purpose of the experiment
Investigate whether the distress that appears in thesubject at the time of pedal misapplication can bedetected by startle blinking reflexes
Description
En people are subjects
Investigate whether blinking appears when the subjects
who simultaneously perform pedal operations throughinformation on the monitor and mental arithmetic withnumbers that are heard through the monitor step on thewrong pedal

Monitor

Scene of an experimentDescription of the Tasks
Pedal operation task: Step on the accelerator when ● appears, and step on the brakes when ● appears
Mental arithmetic task: Verbally answer the sum of the number heard immediately before and the number heard mostrecently (during the preceding pedal operation task)
Pedal operation
task

Mentalarithmetic task

Answer the sum of
the two numbers

Answer the sum of
the two numbers

Instructing the first number before
the experiment

Reaction

Xnp: Pedal operation time

in: Time elapsed until stimulus presentation

Xnp + Xns: Response time for the mental arithmetic task

n: Number of trials

Analysis
Independent variables: Presence or absence of arousal of distress; two levels
Define the FB stimulus (sound and image that the driver who has stepped on the wrong pedal is thought toperceive) that causes the subjects to become distressed. There are two levels: Case where the FB stimulus
is presented when the driver steps on the wrong pedal (FB: driver distressed), and the case where the FB
stimulus is not presented (NO-FB: driver not distressed).
→ This is to compare the case of actual pedal misapplication and the case when that does not occur.
Dependent variables:
These shall be the number of startle blinking reflexes observed when there is pedal misapplication, the time(latency) when blinking appears, and the amount of distress evaluated by the subject (figure between 0 and 10).
Definition of blinking: Blinking that appears within 80 ms from the moment of pedal misapplication
FB stimulus
Driver’s perception at the time ofpedal misapplication reproduced
by presenting this.

OrImage of accident

Stimulation by sound(sound associated with sudden acceleration ofthe automobile)Result of the Experiment: Changes in Distress Due to Presence or Absence of FB

Changes in the amount of the subject’s distressdue to the presence or absence of presentation ofFB stimulus
In this experiment, the subjects were distressed
every time that pedal misapplication occurred.
The subjects were further distressed as a result of
the presentation of FB stimulus (perception of thedriver at the time of pedal misapplication).
(Student’s t test; t(40)=5.429, P<.000)

The average value of the subjective evaluation of thedistress felt by the subjects depending on the presenceor absence of FB stimulus at the time of their pedal
misapplication

Result of the Experiment: Blinking Latency

Comparison between blinking latency (time that blinkingappeared) and frequency due to the presence orabsence of FB stimulus
A reaction (red circle) thought to be a blinking reflex
was observed in one case only.
It could not be said that there were differences in theaverage value of latency depending on the presence orabsence of FB stimulus presentation.
(Student’s t test; t(26)=-.250, n.s.)

All data of 10 subjects who showed blinking

Summary

There is difficulty in using blinking information alone as a method of detecting distress in drivers whostepped on the wrong pedal; it is necessary to combine this with another index.
In this experiment, the subjects were distressed every time that pedal misapplication occurred.
In this experiment system, it is not clear whether differences appeared in the average latency value of blinking
due to the amount of distress felt by the subjects.
It is possible that blinking latency may change because the timing of the occurrence of blinking changes when
the timing where the subject is startled is different from the timing where the subject steps on a pedal.

Future Outlook•

Distress detection will be conducted not only using blinking but also using it in combination with otherphysiological indices.
→ The subjects’ muscle contraction information, heart rate information, etc.

•Build a system where distress information is entered into an automobile control system for reducing
accidents

FAQQ. Will the distance between the accelerator and brake pedals affect pedal misapplication?
A. In the NHTSA report, there is no mention that pedal separation directly affects pedal misapplication.
However, there exists statistical information from accident data that people who are tall are affected by thedistance between the pedals. In other words, it is reported that tall people are more prone to pedal
misapplication accidents when the distance between the pedals becomes wider, while there is no suchtendency among people who are short. In this experiment using a driving simulator, such tendency has notappeared directly, but if the distance between the pedals changes due to body height, it is thought that there isa possibility that as a result, this could lead to pedal misapplication.
Q. Can the distress felt by a driver in the event of a driving error be detected before it leads to an accident?
A. It is believed that prediction/detection of the distress felt by drivers in the event of a driving error issufficiently possible using biological signals. This time, we focused on “startle blinking reflex,” blinking that
occurs when a person is surprised, but unfortunately, the driver’s state of distress could not be detected.
However, we believe that by using the “contraction of muscles of the face and upper body” that appears when aperson is surprised, “hear rate information,” and other biological indicators, distress can be detected, and we
also believe that such information can be used to control automobiles to reduce accidents.

References
Collins, W., Evans, L., & Hughes, R.: Driver brake and accelerator controls and pedal misapplication rates in North Carolina. Washington,
DC: National Highway Traffic Safety Administration, Report No. DOT HS 812 058,2015
Preventing Driving Operation Errors (ITARDA Information Traffic Accident Analytical Report No. 107)https://www.itarda.or.jp/itardainfomation/info107.pdf
Noriaki Tsuchida: Classification of Inhibitory Function, The Literary Association of Ritsumeikan University,
Vol. 500, pp. 100-109, 2007
Yoshiaki Nihei: オートマチック車の運転エラーとシステム・デザイン-認知工学の観点から-, The Operations Research Society of Japan, pp. 1017, 2000
Ryoko Fukuda: Special Issues No.3：Measurement Technique for Ergonomics, Section 2：Measurements of Human Response Effected by the Ambient
Environment. （3）Measurement of Visual Environment and Human Visual Function, The Japanese Journal of Ergonomics, Vol. 51, No. 2, pp. 86-96 (2015)
Shinpei Kodani and Jinglong Wu: Safety Placement of the Car Pedal by Measurement of the Human Legs Joint Angle and Action Time, Transactions of the JSME,
Vol. 76, pp. 134-141, 2010
Fumio Yamada: 瞬目による感性の評価 -驚愕性瞬目反射と自発性瞬目による感情評価-,
Japanese Psychological Review, Vol. 45, No. 1, pp. 20-32 (2002)