NSK says it has developed an electrical power steering (EPS) system equipped with Active On-Centering (steering wheel return) control.
When the driver returns a steering wheel to a centre position, the intention of car movement/trajectory may be off due to a different direction between the steering operation and the car heading, notes NSK.
If the steering wheel does not smoothly return to the centre position especially when making a large turn at an intersection and then moving straight forward, or when making small corrections when driving straight, the driver must make large corrective operations or repeated corrective actions.
To solve the issue, NSK modified the control for adjusting the optimal steering wheel return and changing assistant force.
This helps prevent worsening return trajectories (for example, the wheel does not return to centre position or uneven returning speed), due to variable amount of mechanical friction and tyre counterforce, making it possible for the steering wheel to smoothly return to the on-centre position.