The relevance of HRV parameters for driver workload detection in real world driving

The automotive industry in Germany is one of the strongest industries, continuously introducing new features for making the driver's life safer and more comfortable. For a couple of years, a trend towards safety systems, considering the driver's status, is observable. Already on the market, e.g. eye motion recognition for fatigue detection will be extended by consideration of additional vital signs. Many research groups already faced the question, which vital signs could be of interest, whereas others concentrated on the realizability of vital sign detection without constricting the driver. One of the most important vital signs, the electrocardiogram (ECG), allows extracting the heart rate variability (HRV), which is known to be affected by mental stress and workload. Latest results of different research groups have shown that an ECG recording in a car is feasible without attaching adhesive electrodes thus making this vital sign potentially available for the next generation advanced driver assistance systems. This paper gives attention to the question which HRV parameters are of interest for driver's workload detection by presenting results of a real world driving study.