Response times and gaze behavior of truck drivers in time critical conditional automated driving take-overs

Abstract

The desire to enable conditional automated driving (CAD) in the near future, entails the challenge to manage drivers’ safe transitions from automation back to manual control. Several factors have been considered in recent years in the passenger car context, while the truck has largely been disregarded. For the first time take-over behavior of heavy-duty truck drivers in time critical take-overs is considered in CAD research. This study analyzes the effect of non-driving related tasks, CAD duration, take-over situations and number of take-overs on reaction times of truck drivers. Gaze behavior was tracked with a remote eye-tracker; reaction times and driver interaction during CAD drives was recorded and analyzed. Two different non-driving related tasks were presented in nine unique take-over situations, while also controlling for the duration of CAD. Contrary to assumption, no influence of non-driving related tasks or CAD duration on reaction times is found. Notably, different reaction times are recorded due to the nine unique take-over situations. Finally, it is shown that our take-over times decrease over the course of the experiment and are far lower than other published reaction times (M = 1.35 s) in the passenger car context. The findings are discussed and implications with regard to other published studies are drawn.