US 2014/0174543 A1Published application

Fail operational modes for an electro-hydraulic system

AssigneeEaton Corporation

InventorMICHAEL BERNE RANNOW

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Abstract

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.

Claims16

Dependent claims

A method for initiating and implementing fail operational modes in an electro-hydraulic system comprising the steps of:

(a) providing a plurality of valve assemblies, each valve assembly having at least one of a pressure sensor and a position sensor in communication with an electronic system controller, the valve assemblies being in fluid communication with a hydraulic actuator;
(b) detecting a fault condition with one of the sensors;
(c) determining a sensor type associated with the fault condition wherein a first sensor type is a fault condition is associated with one of the pressure sensors and a second sensor type is associated with a fault condition one of the position sensors.
(d) determining a sensor location associated with the fault condition wherein a first location is associated with a sensor located at an upstream side of the actuator and a second location is associated with a sensor located at a downstream side of the actuator;
(e) where a position sensor has failed, determining an actuator state the actuator being in a passive state or an overrunning state;
and
(f) initiating and implementing one of a plurality of fail operational modes based on the determination of the sensor type, the sensor location, and the actuator state associated with the fault condition.

4 more elements

A method for initiating and implementing fail operational modes in an electro-hydraulic system comprising the steps of:

(a) providing a plurality of valve assemblies, each valve assembly having a pressure sensor in communication with an electronic system controller, the valve assemblies being in fluid communication with a hydraulic actuator;
(b) detecting a fault condition with one of the pressure sensors;
(c) determining a sensor location associated with the fault condition wherein a first location is associated with a sensor located at an upstream side of the actuator and a second location is associated with a sensor located at a downstream side of the actuator;
(d) initiating and implementing one of a plurality of fail operational modes based on the determination of the sensor location associated with the fault condition.

1 more element

Dependencies are inferred from the claim text.