Defining the Operator Interface of a Snowplow Lane Tracking System from Field Interviews and Surveys

Maintaining lane position during low-visibility conditions can be a challenge for snowplow operators. Providing continuous and accurate lane position information to complement existing roadway cues may be the solution to increasing driver awareness. The first phase of a systemsbased approach to designing the operator interface for a snowplow lane tracking system is described. Through a systems-based approach, not only can the type of controls and displays to use for the operator interface be better defined, but the interface's role and the amount, type, and presentation of information can be determined. In this first phase, ridealong interviews and an operator survey were used to identify factors affecting forward visibility and lane position in snowplow operations. More than 1,000 department of transportation snowplow operators from Iowa and Minnesota completed the survey. Ride-along drives showed that operators frequently lose sight of the forward roadway for brief periods and use several cues to adjust the lane position of their vehicles. Survey findings indicated that center and shoulder lines are helpful and intuitive cues for left- and right-wing plow operations. Additional findings suggest that operators need a flexible system that enables them to adjust alarm thresholds and that the operator interface should be designed as an aid rather than as a primary display. Because drivers do not have the visual resources for a dedicated display, a peripheral visual or haptic (tactile) display could be used to complement existing roadway cues.