This paper describes how polar plots are constructed and used to evaluate fields of view from vehicles. A polar plot presents a driver's three dimensional view of the vehicle structure, such as the window openings or mirrors, and the objects outside of the vehicle, such as other vehicles in adjacent lanes, in a two dimensional angular (or polar) field.
These plots are simple and effective in understanding and visualizing complex visibility problems. Since the plot is made in angular space, a Human Factors Engineer can use the plots for direct assessment of drivers' visual problems, such as sizes of monocular and binocular obscurations. Location of visual targets in the driver's peripheral vision, and magnitude of eye and head turn angles, can be easily determined by measuring coordinates of details shown in a polar plot.
A PC-based computer program has been developed to generate polar plots under a wide variety of options, including choice of vehicles, eye points, views, targets, and mirrors. This paper includes examples of polar plots and illustrates how they can be used by an automotive designer to evaluate many specific problems. Example problems illustrated include: 1) angular locations of pillars, 2) monocular and binocular obscurations caused by pillars, 3) hood visibility, 4) visibility of adjacent vehicles, and 5) fields of view available from planar and convex mirrors.