Failure-Tolerant By-Wire Actuator Interface

A by-wire control system for a vehicle, comprising:

• a sensor assembly manipulated by a driver of the vehicle that produces a first electrical signal indicative of a driver command for a vehicle control parameter;
• an external control unit for producing a second electrical signal indicative of an external command for said control parameter;
• an actuator that regulates said control parameter in accordance with a third electrical signal indicative of a final command for said control parameter;
• and
• an interface circuit that merges said first and second electrical signals to form said third electrical signal, including a filter circuit that blocks said second electrical signal during specified fault modes of said external control unit while otherwise passing said second electrical signal a filter circuit output, and a merging circuit for setting said third electrical signal equal to said first electrical signal when said driver command equals or exceeds said external command, and otherwise setting said third electrical signal equal to said filter circuit output.