A study of 24 professional truck drivers investigated how drowsiness develops during real-road driving to test a DDAW system. At night, 17 of 24 drivers reached a KSS level of 8, with average time to reach KSS 8 being 56 minutes. Ten drivers chose to stop or were requested to stop in the sleep-deprived condition. A DDAW recording window of 600 s would fail to capture information relevant to the EDR, whereas time windows of up to one hour could provide important indications of increased driver fatigue.

Proposal to increase yaw rate recording frequency to 10 Hz. Yaw-rate data recorded at 2 Hz corresponds to one measurement every 500 ms; increasing to 10 Hz provides a measurement every 100 ms, resulting in a fivefold improvement in temporal resolution. This enhancement significantly improves ability to reconstruct pre-crash vehicle dynamics, identify vehicle instability onset and progression, and evaluate Electronic Stability Control functionality. A yaw-rate recording frequency of at least 10 Hz reduces temporal uncertainty from 500 ms to 100 ms and enables more accurate reconstruction of loss-of-control events, vehicle rotation, ESC interventions, and driving dynamical issues.