US Patent 7827001 Method for fault detection in an actuator

A method for detecting fault in an actuator. By transmitting a control value, which is generated by a control unit, to an input of the actuator a signal for the measured actuator position is produced at the output of the actuator. The signal for the measured actuator position is sent to an input of a signal conditioning unit which determines from it a measure of actuator movement. The control value is also transmitted to an input of a modeling unit, which calculates from it an expected measure of actuator movement. These movements are sent to a computer unit, which produces a corresponding status signal for the functionality of the actuator and for the functionality of the sensor for determining the actuator position.