### The contribution of stereo vision to the control of braking

Pieter Tijtgat, Liesbeth Mazyn UGent and Matthieu Lenoir UGent (2007) p.105-106
abstract
Introduction To be successful in the confusion of daily traffic, executing appropriate brake manoeuvres is an important skill. When following a car, a driver needs to be alert in order to quickly register and act upon decelerations of a leading vehicle. From the literature, it can be concluded that monocular information sources like the optical variable tau play an important role in the visual control of braking, but that several other visual cues, such as depth information from stereo vision, might have a supplement impact on brake behaviour. In present experiment, the contribution of stereo vision was investigated when performing a braking task Methods 26 female participants with normal (≤ 40 arcsec on a Grade Circle Test; StereoN; N = 13) or weak (≥ 800 arcsec; StereoW; N = 13) stereo vision performed braking tasks when driving at a speed of approximately 11 km/h on a go-cart. Subjects could start braking at 4, 7 or 10 meters from a target vehicle when a red lamp on the rear of this vehicle lit. The momentanuous position of the go-cart was measured at 200Hz with a laser (Noptel CMP2-30) and velocity and acceleration were calculated. From these data, time and distance of brake initiation, and time of maximal deceleration were calculated as principal dependent variables and submitted to a 3 (conditions of distance: 4m vs. 7m vs. 10m) x 2 (group conditions: stereoW, stereoN) ANOVA with repeated measures on the first factor. Results StereoW group started braking earlier in time than StereoN (p≤.05). In the braking adjustment phase, maximal deceleration occurred closer in time to contact for StereoN group than StereoW (p<.01). This effect increased up to 2596 msec in the 10m-condition, as the interaction effect showed up (p<.01). StereoN group reached standstill on a greater distance than StereoW group (p<.05). Conclusions From this experiment, it can be concluded stereo vision contributes to the initiation as well as to the control of a braking manoeuvre. However, this does not mean that people with a lack of stereo vision may cause greater risks in traffic negotiation, in particular situations in which rear-end collisions may occur. The lack of good stereo vision is even associated with more prudent brake behaviour, i.e. an earlier brake initiation and an earlier maximal deceleration.
author
organization
year
type
conference
publication status
published
subject
in
Book of abstracts : European Workshop On Movement Science
pages
105 - 106
publisher
Sportverlag Strauss
place of publication
Köln, Germany
conference name
European Workshop On Movement Science (EWOMS)
conference location
Amsterdam, The Netherlands
conference start
2007-05-31
conference end
2007-06-02
ISBN
9783939390732
language
English
UGent publication?
yes
classification
C3
I have transferred the copyright for this publication to the publisher
id
1060660
handle
http://hdl.handle.net/1854/LU-1060660
alternative location
http://doc.utwente.nl/59823/1/Abrahamse07contextual.pdf
date created
2010-10-19 16:11:57
date last changed
2017-01-02 09:52:19
@inproceedings{1060660,
abstract     = {Introduction
To be successful in the confusion of daily traffic, executing appropriate brake manoeuvres is an important skill. When following a car, a driver needs to be alert in order to quickly register and act upon decelerations of a leading vehicle. From the literature, it can be concluded that monocular information sources like the optical variable tau play an important role in the visual control of braking, but that several other visual cues, such as depth information from stereo vision, might have a supplement impact on brake behaviour. In present experiment, the contribution of stereo vision was investigated when performing a braking task

Methods
26 female participants with normal (\ensuremath{\leq} 40 arcsec on a Grade Circle Test; StereoN; N = 13) or weak (\ensuremath{\geq} 800 arcsec; StereoW; N = 13) stereo vision performed braking tasks when driving at a speed of approximately 11 km/h on a go-cart. Subjects could start braking at 4, 7 or 10 meters from a target vehicle when a red lamp on the rear of this vehicle lit. The momentanuous position of the go-cart was measured at 200Hz with a laser (Noptel CMP2-30) and velocity and acceleration were calculated. From these data, time and distance of brake initiation, and time of maximal deceleration were calculated as principal dependent variables and submitted to a 3 (conditions of distance: 4m vs. 7m vs. 10m) x 2 (group conditions: stereoW, stereoN) ANOVA with repeated measures on the first factor.

Results
StereoW group started braking earlier in time than StereoN (p\ensuremath{\leq}.05). In the braking adjustment phase, maximal deceleration occurred closer in time to contact for StereoN group than StereoW (p{\textlangle}.01). This effect increased up to 2596 msec in the 10m-condition, as the interaction effect showed up (p{\textlangle}.01). StereoN group reached standstill on a greater distance than StereoW group (p{\textlangle}.05).

Conclusions
From this experiment, it can be concluded stereo vision contributes to the initiation as well as to the control of a braking manoeuvre. However, this does not mean that people with a lack of stereo vision may cause greater risks in traffic negotiation, in particular situations in which rear-end collisions may occur. The lack of good stereo vision is even associated with more prudent brake behaviour, i.e. an earlier brake initiation and an earlier maximal deceleration.},
author       = {Tijtgat, Pieter and Mazyn, Liesbeth and De Laey, Christophe and Lenoir, Matthieu},
booktitle    = {Book of abstracts : European Workshop On Movement Science},
isbn         = {9783939390732},
language     = {eng},
location     = {Amsterdam, The Netherlands},
pages        = {105--106},
publisher    = {Sportverlag Strauss},
title        = {The contribution of stereo vision to the control of braking},
url          = {http://doc.utwente.nl/59823/1/Abrahamse07contextual.pdf},
year         = {2007},
}


Chicago
Tijtgat, Pieter, Liesbeth Mazyn, Christophe De Laey, and Matthieu Lenoir. 2007. “The Contribution of Stereo Vision to the Control of Braking.” In Book of Abstracts : European Workshop On Movement Science, 105–106. Köln, Germany: Sportverlag Strauss.
APA
Tijtgat, P., Mazyn, L., De Laey, C., & Lenoir, M. (2007). The contribution of stereo vision to the control of braking. Book of abstracts : European Workshop On Movement Science (pp. 105–106). Presented at the European Workshop On Movement Science (EWOMS), Köln, Germany: Sportverlag Strauss.
Vancouver
1.
Tijtgat P, Mazyn L, De Laey C, Lenoir M. The contribution of stereo vision to the control of braking. Book of abstracts : European Workshop On Movement Science. Köln, Germany: Sportverlag Strauss; 2007. p. 105–6.
MLA
Tijtgat, Pieter, Liesbeth Mazyn, Christophe De Laey, et al. “The Contribution of Stereo Vision to the Control of Braking.” Book of Abstracts : European Workshop On Movement Science. Köln, Germany: Sportverlag Strauss, 2007. 105–106. Print.