Effects of retroreflector positioning on nighttime recognition of pedestrians

Abstract

This field study investigated potential effects of retroreflector positioning on recognition of nighttime pedestrians. The subject's task was to press a response button whenever he/she recognized a pedestrian on or alongside the road, while in a car with low-beam lamps on that was driven at a constant speed on a dark road. The results showed that each retroreflector configuration yielded significantly longer recognition distances than the no-retroreflector configuration. More importantly, the retroreflective markings attached to the limbs led to significantly longer (about 60-80%) recognition distances than when the retroreflective markings were attached to the torso. Furthermore, a pedestrian was more recognizable while crossing the road than while approaching the subject vehicle, except for configurations involving no retroreflective markings.

Using biological motion to enhance the conspicuity of roadway workers

“…Researchers have also begun to identify the neural mechanisms involved in the perception of biomotion (Grossman et al, 2000(Grossman et al, , 2005. Meanwhile, there has been interest in capitalizing on our perceptual sensitivity to biomotion in order to enhance drivers' ability to recognize pedestrians (including road workers), from a safe distance at night (Balk et al, 2008;Blomberg et al, 1986;Luoma and Penttinen, 1998;Luoma et al, 1996;Owens et al, 1994;Sayer and Mefford, 2004;Tyrrell et al, 2009;Wood et al, 2005).…”

“…Emerging research by our group and others has demonstrated that pedestrians are even more conspicuous to drivers at night when retroreflective material is attached to the pedestrian's major moveable joints (Balk et al, 2008;Blomberg et al, 1986;Luoma and Penttinen, 1998;Luoma et al, 1996;Owens et al, 1994;Sayer and Mefford, 2004;Tyrrell et al, 2009;Wood et al, 2005). Using a variety of methods (laboratory-based videos and closed and open-road evaluations), these studies have demonstrated that retroreflective strips positioned in the full biomotion pattern provide substantial advantages for improving pedestrian visibility, which result more from the pedestrian's motion than from highlighting the pedestrian's form (Balk et al, 2008).…”

Pedestrian conspicuity at night: failure to observe a biological motion advantage in a high‐clutter environment

“…Attempting to equate the amount of retroreflective areas between conditions, Luoma et al (1996) report a field study in which participants performed a recognition task while being driven in a car travelling at 50 km/h. In this experiment, pedestrians appeared either crossing the road or walking towards the experimenter and were filmed in a single, unilluminated road environment.…”

Review of studies on pedestrian and bicyclist safety, 1991-2007

“…Studies also show that the positioning and color of retro-reflective material is important. One study reported that retro-reflective markings attached to arms or legs produced recognition distances 60 to 80% greater than markings attached to the torso, which in turn had twice the recognition distance than pedestrians without any markings at all (Luoma, Schumann, & Traube, 1996). Examining the visibility of retro-reflective material, one study demonstrated that materials reflecting red, yellow, and green colors were detected at similar distances at night, and all at significantly greater distances than white materials of the same intensity (Sayer, Mefford, Flannagan, Sivak, Traube, & Kojima, 1998).…”