Hyundai Mobis developed an electric power steering system which uses the redundant control mode that takes advantage of two electronic circuits during autonomous driving to maintain normal steering capabilities under any circumstances.
Things will be different in the autonomous driving mode. As the driver is not looking ahead during autonomous driving, if the steering system has any problem, the driver cannot intervene immediately, and the risk of an accident will increase. Therefore Hyundai Mobis has two independent electronic circuits that are applied to one steering system in the event of one circuit breaking down, the other circuit will work normally and maintain stable driving.
The two systems watch over each other through high-speed communication, and check if the counterpart is working normally. If a problem is detected, System No. 1 is turned off, and System No. 2 will be activated. This is how the vehicle is controlled. As a result, the vehicle can maintain a normal steering status.
The normal operation of the steering system in the autonomous driving environment in which the vehicle operates on its own without the driver’s control is a requirement directly related to the safety of passengers. Even if the steering system runs into an unexpected problem while the car is being driven, the system must detect the issue by itself and normally control the steering wheel before stable autonomous driving is possible.
Source: Hyundai Mobis