Lane-keeping assistance systems support drivers and can prevent them from leaving their lane (e.g. in case of microsleep or distraction). In order to keep users from permanently doing something else, one hand must remain on the steering wheel. One aspect that needs to be taken into account in designing lane-keeping assistance systems is that of the degree of lane deviation to be tolerated by the system. If the system intervenes too early, lane-keeping behavior feels unnatural. If the intervention comes too late, the vehicle will constantly veer from one lane marking to the other.
Another issue concerns the attention of drivers: Will the assistance provided distract drivers from the task of driving to the extent that they will no longer be able to resume control in time once the system reaches its limits?