Limitations in Drivers’ Ability to Recognize Pedestrians at Night 學生：董瑩蟬

Purpose This paper investigated the pedestrian which wear different color clothing for driver found they distance at night. The experiment also investigated the car headlight illumination, pedestrian position and age different effect the distance or not.

Reference Pedestrian crashed at night has 65% on the collisions accident. (NHTSA,2005) The illumination declined were indicate the pedestrian crash risk. (Owens et al.,1996; Flannagan,2002)

Reference Many studies employ video and slide to investigated the pedestrian clothing color which effected the driver vision or not. (Owens et al.,1994) Some studies employ distance measure the driver recognize. (Chrysler et al.,1996)

Method Participants –10 older – age between 60 to 75(M=67.9),7M and 3F –10 younger – age between 21 to 34(M=27.8),3M and 7F –Restrict – licensed, vision over 0.5 Equipment –Experiment vehicle Nissan –Video cameras –Radio –Red LEDs

Method Independent variables –Age: older and younger –Pedestrian clothing color: black, white, vest, biomotion –Vehicle headlight: low and high beam –Pedestrian position: see fig 1 Dependent variables –Recoginzed percentage –Recoginzed distance

Method Process –All Participants were volunteer –All participants test 10 circle (the first one was train, the second test Reaction time,3~10 data collect) –Driver press the button when they found the pedestrian –The data collect the correct rare and distance –The experiment area was next page figure 1

Method

Result The participants background –The older driver has 45.8 years driving experience, and younger 7.9 years. –The older has significantly less time drive at night than younger. (M=12.7% and 34%, t(18)=3.2,p=0.005) –The older has less comfortable than younger. (t(18)=-2.3,p=0.035)

Result The reaction time of the second circle, they found the older (1.54 s) and younger (1.59 s) has no different. The mean speed has no significantly different on the older and younger when they see the pedestrian to press the button.(67.7 and 70.7km/hr, t(63)=1.7) People drive an circle mean time found that the older (147.6 s) has longer time than younger (137.5 s) t(18)=-2.3,p=0.03.

Result

When on glare, the driver found the pedestrian percentage was 76.3, and 76.5 on the glare. The older driver found the pedestrian percentage was 53.2, and younger was The four different clothing color for driver found percentage was follow biomotion was 93.8, white 83.8, vest 63.8, black 33.8, The low beam for driver found the pedestrian was 63.2, and high beam was 74.4.

Result The found the percentage significantly different describe follow: Item Clothing color χ2(3) = 64.5, Headlight χ2(1) = 7.9 Age χ2(1) = 41.6 Glare χ2(1) = 13.3

Result

The driver found the pedestrian that mean distance were 76.5 m The black clothing has short distance to found the pedestrian, and biomotion has longer distance to see. The older found the pedestrian distance was 56m, and younger was 97m.

Result Used the ANOVA analysis two within (color and headlight) and one between (age), found the variable for the distance significant. Variable significant Clothing F(3, 54)=49.29, P<0.001 Headlight F(1, 18)=11.07, P=0.004 Age F(1, 18)=10.54, P=0.004

Discussion The older driver found the pedestrian presence and distance all worse than younger. The result similar to Chrysler et al.(1996) and Luoma et al.(1996). The older has worse contrast sensitivity. (Elliott et al.,1990; Higgigns et al.,1988…) The headlight beam also effected the driver to found the pedestrian. Olson (1974) and Shinar(1984) has similar found that.

Discussion Pedestrian wear clothing color may effect the driver to found they. Some studies has showed that the black decline the visibility distance. (Allen et al.,1970; Luoma et al.,1996) The pedestrian contrast increased that the driver can easy found they. (Blomberg et al.,1986; Luoma et al.,1996…)

Conclusion The older driver has worse performance than younger,include driver found the pedestrian presence and distance. Black is the worst color that driver to recognize the pedestrian. The low beam was an bad factors for driver found the pedestrian.