Simulator Study of Driver Responses to Pedestrian Treatments at Multilane Roundabouts.

Previous studies have shown that roundabouts - especially multilane roundabouts - pose accessibility challenges to pedestrians with vision impairments, in part due to a lack of yielding by drivers, especially on multilane roundabout exit legs. In this study, three different treatments are assessed in terms of their propensity for increasing driver yielding rate using a driving simulator. These are stop bar and crosswalk relocation away from the beginning of exit leg, and two types of beacons, namely a Pedestrian Hybrid Beacon (PHB) and a Rectangular Rapid Flashing Beacon (RRFB). The study shows that installation of any kind of beacon (PHB or RRFB) with or without crosswalk relocation increases driver yielding rates significantly. Relocating the crosswalk does not provide a significant increase in driver yielding rate for the base case, but appeared to further enhance the effectiveness of the PHB and RRFB treatments. The results of using an eye tracker on drivers to track their gaze pattern while exiting the roundabout shows that having a beacon installed with crosswalk relocation increases drivers' attention both on the beacon and the pedestrian along the road. However, a portion of participants failed to see and react to the pedestrian treatments, causing concern about the visibility of these treatments at the roundabout exit leg.