Workload Assessment of IN-CAB Text Message System and Cellular Phone Use by Heavy Vehicle Drivers on the Road

Abstract

This study assessed the driver workload imposed by a text messaging system and cellular phone on heavy vehicle drivers under various driving conditions. Sixteen (16) professional commercial vehicle operation (CVO) licensed drivers drove an instrumented heavy truck over a 4-hour period on public roads under various conditions of ambient lighting (day or night), traffic density (light or heavy), and road type (divided or undivided). Within driving condition combinations, various levels of text message reading, cellular phone dialing, radio tuning, and communications dialogue were completed by the driver. Continuous measures were taken of visual allocation, steering and accelerator activity, speed maintenance and lane-keeping performance. Results of in-vehicle device use are presented and provide insights into useful workload measures and methods, as well as a contribution to the literature on cellular phone and in-vehicle text messaging system ergonomics.