Forward looking blindspots: A report of A-Pillar induced field-of-view obstruction and driver performance in a simulated rural environment

Forward-looking blindspots occur when the driver’s field of view is compromised as a result of the obscured line of sight produced by the support pillar on either side of the windshield, also known as the A-pillar. This differs from the “traditional” concept of the rear-view blindspot. This obscured region enables an approaching vehicle to remain hidden for an extended time due to coincident acceleration or deceleration. This interaction holds serious implications for real world events as well as research results in traffic interactions and automotive design. This study analyzed the relationship between the size of the forwardlooking blindspot (FLB), the approach speeds of two vehicles approaching an intersection at right angles, and driver behavior relative to an accident likely event. The wrap around simulator (WAS) at the University of Minnesota Human Factors Research Lab (HFRL) is a large dome like structure with wrap around screens and multiple projectors that produce a forward field of view image of approximately 130 degrees about an instrumented vehicle. At each simulated intersection, the manner in which the participants scanned the virtual environment was observed and scored in four categories or levels: I. Eyes fixed- peripheral vision only II. Eyes only scan- left/right, no head motion. III. Eye/head scan – head rotates but no change in position IV. Active scan – head moves around left/right, forward/back (looking around A-pillar) Participants were also scored as to target vehicle acquisition and collision. Acquisition increased at each increased level of scanning and the collision rate decreased at the “active” scanning levels (III & IV). Signage (yield) at intersections produced no significant correlation with the acquisition rate, collision rate or scanning level). It would appear that in the interaction between automotive design, traffic systems and driver behavior, the complacency or resulting inactivity of the driver’s scanning behavior can produce a common and hazardous driving condition. This issue applies to automotive and pedestrian traffic as well and explains to some degree why pedestrians often seem to appear in the road as one initiates a left or right turn.