FAIL OPERATIONAL MODES FOR AN ELECTRO-HYDRAULIC SYSTEM

Methods for initiating and implementing fail operational modes in an electro-hydraulic system are disclosed. In one step, a plurality of valve assemblies is provided wherein each of the valve assemblies has a pressure sensor and a position sensor in communication with an electronic system controller. The valve assemblies are in fluid communication with a hydraulic actuator, for example a linear actuator or hydraulic motor. In one step, a fault condition with one of the sensors is detected. The method may also include the steps of determining the type and location of the sensor associated with detected fault condition. In another step, an actuator state is determined wherein the actuator is in a passive state or overrunning state. Another step is initiating and implementing one of a plurality of fail operational modes based on the determination of the sensor type and location, and the actuator state.