The overall goal of the project is focused on incrementing the efficiency of Electro-Mechanical and Electro-Hydrostatic systems in terms of extending the life and improving the reliability and enhancing the performance of the maintenance activities of wing actuation systems. It means to investigate and improve innovative sealing and sensor solutions, combined with health monitoring technologies, able to monitor the actuation systems and to detect and predict failures at an early stage in order to avoid a catastrophic fault. With this objective in mind, the activities within the project have been oriented to the following goals:
Innovative and alternative sealing solutions that are able to reduce the friction, wear and leakage at high level of deformation monitored in accelerated seal tests. To increase lifetime to thermal cycles of the seals.
Innovative and alternative lubricant solutions that are able to reduce friction and wear and to increase extreme pressure properties, increasing the temperature limit and time to a fixed temperature in relation to reference lubricants. The best lubricating alternatives will be tested in order to quantify their capacity to extend their lifetime.
New oil sensing systems to monitor the status of the lubricant (chemical and physical parameters along with inspection of solid particles) with a twofold aim: identify faulty conditions and extend the life of the lubricant.
The lifetime control (friction, wear) of the selected gears materials and lubricants was performed by means of accelerated simulated tests monitoring in parallel both vibrations and wear, in order to create the right knowledge for conditions monitoring.
Develop, implement and integrate Health Monitoring algorithms to predict failures before affecting the actuator output in a critical way.
Conclusions
There have been 3 main conclusions, that impact the three pillars of the project.
Extension of the life of seals: Different seal/lubricant pairs were be selected and tested in order to find sealing solutions providing a longer service life. The validation of the performance of the different new proposed sealing systems and lubricants was performed through simulated tests at lab scale and the most promising tribo-systems were validated using the advanced test rig TESSA, were aeronautical working conditions were simulated in an electro hydraulic actuator. The information gathered will impact the design of future electro hydraulic actuators, improving the life of the seal-hydraulic par.
On-line monitorization of the hydraulic fluid: In ISSELUB it was decided to adapt and modify the oil health and oil-wear sensors (oil quality and wear debris sensor) for the working conditions of electro-hydraulic actuators. A new line of Oilhealhtand Oilwear sensors is being developed, bringing to the market the product of the research done in the project. On the other hand the monitoring of some of the EHA parts has given insight of the degradation process. This valuable information will be used in future designs.
Health monitoring of mechanical components: ISSELUB advanced the state-of-the-art in health monitoring by developing, implementing and validating a health monitoring solution for actuators. It was targeted to develop technologies to efficiently exploit the information of sensors for failure detection and diagnostics. The tests and the health algorithm developed have an impact in future designs, as they will be safer and more efficient.
