Measurement of Driver’s Mental Workload in Partial Autonomous Driving

Autonomous driving has the potential to be the next critical technology that changes the lifestyle of a human. It has, however, not been verified whether the autonomous technology at different lower levels decreases or increases the mental workload of drivers. This paper verifies the relationship between a driver’s mental workload and level 0, 1 and 2 of autonomous driving using NASA-TLX and adjusted response time in a secondary task simulation study. Experiment results show that level 1 causes the lowest mental workload of the driver, followed by level 2 and level 0. We discuss this nonlinear relationship between the levels of autonomous driving support and the mental workloads incurred to the human driver.