Wireless condition monitoring of freight locomotives

Key technical challenges include overcoming the space constraints and the vibration and shock environment on Locomotive bogies. A smaller lighter vibration energy harvester takes less space but the problem with smaller proof masses is that they are intrinsically less powerful. Therefore, a significant challenge has been to achieve more power per unit mass. Lower power levels mean critical challenges in the efficient storage and use of the energy available from the harvester. The challenge is also to make the whole Wireless Sensor Node (WSN) and its bracket more resilient and reliable in these extreme conditions. This would be a "First of a Kind" installation as the new product has not previously been installed. The new design has specific advantages for locomotive monitoring, including smaller and stiffer mount for the vibration sensor and a slimmer, lighter form factor to address the problems of restricted space on a locomotive and the higher levels of vibration expected. The new system will be integrated with a freight maintainer/operator/owner maintenance system with the unique opportunity to develop optimised freight locomotive maintenance with a national distribution of freight maintenance depots. Earlier development projects (including the InnovateUK funded ENERGYMAN) have enabled Perpetuum to innovate much improved energy efficiency and power management in the harvester and WSN for this project. This proposed installation will enable us to demonstrate that this new type of significantly improved WSN with about 60% lower weight and volume will be able to withstand the very challenging environment. The experience gained from attempted installations of the original WSN design on a locomotive and in some severe passenger train environments as well as extensive in-house shock and vibration testing all give us confidence that this revolutionary new harvester and WSN will operate successfully. We expect that some culture and organisational change to maintenance methodology will be required for the successful implementation of condition based maintenance and this will require appropriate information, presented in a useful format to be developed and agreed with the customer. Lathe wheel turning practices and bearing inspection and change routines must be understood so that optimised logistics for vehicle maintenance can be devised and implemented. Wheel and bearing life extension strategies matched to the application will be designed in conjunction with the customer. Study will be required for wheel degradation rates to predict achievable wheel life. Innovation - the new node design enables freight loco wheel monitoring for the first time. Innovation is in both the application, which is special due to the particular use and duties of freight locos and also in the product being used. Track maps will be produced showing locations of flats, noise, and track quality as experienced by the locomotive. Identifying causes of excessive vibration and noise should then enable remedial action to be targeted at noise reduction. During the short run time of the project sufficient information should be gathered to demonstrate that it is possible to use real time condition to optimise wheel management. In summary the key technical challenges have been to produce a smaller, lighter, reliable WSN for freight locomotives, to improve the energy efficiency of the system and to use the data effectively to improve maintenance procedures and hence resilience and cost of freight locomotive operations. The objectives are primarily to increase the reliability and resilience of freight operations with significant cost savings associated with wheel management on freight locomotives: - Fewer visits to wheel lathes - Reduced inspections and changes of bearings - Better planning of wheel maintenance operations - Elimination/significant reduction of trackside wheel impact alerts causing disruption to service - Increased wheel life - Improved unit availability. It is anticipated that the associated general improvement in wheel quality will reduce noise from the wheel/rail interface, reduce unplanned journeys to maintenance depots and improve traction efficiency. There are secondary objectives to use the system's track monitoring capability to map track quality, detect localised noise sources and identify the location of wheel defect occurrences. There is significant potential to extend installations to other operators in Europe of these EMD manufactured locomotives. If resources permit, a trial installation could also be made on a DRS class68 built by Stadler. There is then potential to extend the monitoring to other vital parts of the locomotive including bearings, diesel engines, gearboxes and other components. There are also plans to monitor freight wagons being hauled by these locomotives, with the data being transmitted by vibration energy harvester powered sensors to the locomotive for onward transmission.