SYSTEM AND METHOD FOR HEATLH MONITORING OF SERVO-HYDRAULIC ACTUATORS

摘要

A method of health monitoring of a hydraulic actuator includes sensing a first hydraulic fluid pressure at a first chamber of a hydraulic cylinder, the first chamber defined by a piston disposed in the cylinder and a first cylinder wall. The method further includes sensing a second hydraulic fluid pressure at a second chamber of the hydraulic cylinder, the second chamber defined by the piston and a second cylinder wall opposite the first cylinder wall. The pressures are summed to derive a pressure sum leakage estimate. An actual piston position in the hydraulic cylinder is determined and compared to an intended piston position to determine a positional error of the piston. A command-response error leakage estimate is derived from the positional error. The pressure sum leakage estimate and the command-response error leakage estimate are fused to determine an internal hydraulic fluid leakage in the hydraulic cylinder.