Driver adaptation to haptic shared control of the steering wheel

Although the benefits of haptic shared control of the steering wheel have been repeatedly demonstrated, longitudinal studies of how drivers adapt to this kind of system are still lacking. The present study addressed this question by comparing two groups of participants in a driving simulator for an extended time period; one group drove with a shared control system and the other drove without. After the practice, all participants drove a final trial with shared control during which a failure of the system occurred. The results show that the evolution of driving performance and the way in which drivers monitored their performance was similar for the two groups. This suggests that the drivers quickly updated their internal model of the steering system dynamics at the sensorimotor level, without further behavioural adaptation afterwards. However, it appears that the internal model was consolidated with repeated use of the system, which translated as a difficulty to compensate for the system's failure. In addition, it appears that drivers did not attempt to maintain a level of task difficulty when steering was facilitated.