Fault prediction in hydraulic systems

A non-transitory computer-readable storage device including processor executable instructions that enable a processor to perform operations comprising:

• pruning a dataset by selecting a subset of the dataset for use as a sanitized dataset based on both command signals for a plurality of deployment events of a hydraulic system and pressure data for the hydraulic system, wherein the pruned dataset includes the pressure data for the hydraulic system correlated in time with the command signals for the plurality of deployment events of the hydraulic system;
• determining that a first pressure value measured during a first extension or retraction of a piston in the hydraulic system, and included in the pruned dataset, satisfies a prefault pressure threshold, wherein the hydraulic system relates to a landing gear on an aircraft, and wherein the first extension or retraction of the piston relates to deployment of the landing gear;
• identifying a first pressure slope value relating to a first change in a first plurality of pressure values over time during the first extension or retraction of the piston;
• identifying a second pressure slope value relating to a second change in a second plurality of pressure values over time during a second extension or retraction of the piston in the hydraulic system, wherein the second extension or retraction of the piston relates to deployment of the landing gear, wherein the second plurality of pressure values are included in the pruned dataset, and wherein the second extension or retraction of the piston occurs earlier in time than the first extension or retraction of the piston;
• determining that the first pressure slope value satisfies a prefault trend threshold based on comparing the first pressure slope value with the second pressure slope value;
• and
• determining, based on both the first pressure value satisfying the prefault pressure threshold and the first pressure slope value satisfying the prefault trend threshold, that the hydraulic system is in a pre-fault state, and in response generating a service message for the hydraulic system.

A system, comprising:

• a processor;
• and
• a memory, the memory including instructions that, when executed by the processor, enable the processor to perform operations comprising:
• pruning a dataset by selecting a subset of the dataset for use as a sanitized dataset, wherein the pruned dataset includes pressure data for a hydraulic system correlated in time with command signals for a plurality of deployment events of the hydraulic system;
• determining that a first pressure value measured during a first extension or retraction of a piston in the hydraulic system, and included in the pruned dataset, satisfies a prefault pressure threshold, wherein the hydraulic system relates to a landing gear on an aircraft, and wherein the first extension or retraction of the piston relates to deployment of the landing gear;
• identifying a first pressure slope value relating to a first change in a first plurality of pressure values over time during the first extension or retraction of the piston;
• identifying a second pressure slope value relating to a second change in a second plurality of pressure values over time during a second extension or retraction of the piston in the hydraulic system, wherein the second extension or retraction of the piston relates to deployment of the landing gear, wherein the second plurality of pressure values are included in the pruned dataset, and wherein the second extension or retraction of the piston occurs earlier in time than the first extension or retraction of the piston;
• determining that the first pressure slope value satisfies a prefault trend threshold based on comparing the first pressure slope value with the second pressure slope value;
• and
• determining, based on both the first pressure value satisfying the prefault pressure threshold and the first pressure slope value satisfying the prefault trend threshold, that the hydraulic system is in a pre-fault state, and in response generating a service message for the hydraulic system.