Driver workload detection in on-road driving environment using machine learning

Drivers' high workload caused by distractions has become one of the major concerns for road safety. This paper presents a datadriven method using machine learning algorithms to detect high workload caused by surrogate in-vehicle (IV) secondary tasks performed in an on-road experiment with real traffic. The data were collected using an instrumented vehicle while drivers performed two types of secondary tasks: visual-manual and auditory-vocal tasks. Two types of machine learning methods, support vector machine (SVM) and extreme learning machine (ELM), were applied to detect drivers' workload via drivers' visual behaviour (i.e. eye movements) data alone, as well as visual plus driving performance data. The results suggested that both methods can detect drivers' workload at high accuracy, with ELM outperformed SVM in most cases. We found that for visual intensive workload, using drivers' visual data alone achieveed an accuracy close to using the combination information from both visual and driving performance data. This study proves that machine learning methods can be used for real driving applications.