Tribo-Acoustic Sensors for In-Situ Performance and Inspection of Machine Components

工程机械，从汽车和飞机，到发电站和生产线，都有许多活动部件。这些部件的可靠性是机器功能和能源效率的关键。通常是这些运动部件失效，而失效通常与摩擦表面有关。像轴承、齿轮、密封件和活塞这样的机器元件经常磨损，表现出高摩擦或卡死。了解机器元件是否处于最佳状态可以节省能源并延长使用寿命。能够在机器中对部件进行现场监控可以加快开发周期。此外，监测性能而不是故障，允许机器操作员计划维护。这对于位于偏远地区的高资本成本机器尤其重要，比如海上风力涡轮机。当前的监测方法是基于测量过度振动或失效部件发出的噪声（声发射AE）或通过计算润滑剂中的磨损碎片颗粒。测量性能而不是故障的传感器，因此可以用于优化操作参数，这将更加有用。这也开启了使用基于传感器读数的高级控制的可能性。许多机器部件都是商品，集成传感器提供了一种增加商品价值的方法。位于谢菲尔德的列奥纳多中心开发了独特的测量机器接触的方法。这些方法是基于无损检测和动力学领域的超声技术。通过发送超声波脉冲通过机器部件和测量传输和反射，我们已经能够无创地研究各种摩擦学机器部件。在早期的工作中，我们开发了测量油膜厚度和金属接触量的方法。这已经很好地建立，在实验室实验验证，并应用于轴颈轴承，信任垫，滚动轴承，活塞和密封件。一些工业公司在其产品开发周期中采用了这些方法。该奖学金旨在探索新的方法，以了解更多的接触。使用不同种类的超声波，换能器拓扑结构和信号处理，我们将开发测量接触负载，应力历史，油粘度和摩擦的方法。这些将在实验室原型，我们有工业合作伙伴准备提供现场应用。此外，该奖学金寻求与学术机构合作；首先学习新的声学传感器技术，其次通过提供新的测量方法来支持机器元件的研究。这将支持莱昂纳多中心的目标，不仅是摩擦学超声波测量的领先中心，而且是英国在工业和学术界的机器部件研究和开发的研究基础设施的关键部分。

Engineering machines, from car and planes, to power stations and production lines, have lots of moving parts. The reliability of these parts is key to the function and energy efficiency the machine. It is often these moving parts that fail and frequently that failure is associated with the rubbing surfaces. Machine elements like bearings, gears, seals, and pistons often wear out, exhibit high friction, or seize.Knowing if a machine element is performing at its optimum can save energy and lead to long life. Being able to monitor the components in-situ in a machine can speed up the development cycle time. Further, monitoring performance rather than failure, allows allows the machine operator to plan maintenance. This is particularly important for high capital cost machines, in remote locations, like offshore wind turbines.Current monitoring methods are based around measuring excessive vibration or the noise emitted by a failed component (acoustic emission AE) or by counting wear debris particles in a lubricant. Sensors that measure performance rather than failure, and so can be used to optimise operating parameters would be much more useful. This also opens the possibility of using advanced control based on sensor readings, Many machine components are commodities, and integrating sensors provides a way to add value to what would otherwise be a commodity product.The Leonardo Centre at Sheffield has developed unique methods for measuring machine contacts in-situ. The approaches are based on ultrasonic technologies adapted from the NDT and dynamics communities. By sending ultrasonic pulses through machine components and measuring transmission and reflection we have been able to non-invasively study various tribological machine components. In early work we developed methods to measure the oil film thickness, and the amount of metal contact. This has been well established, validated in laboratory experiments, and applied to journal bearings, trust pads, rolling bearings, pistons, and seals. Several industrial companies have adopted these approaches in their product development cycles.This fellowship seeks to explore new methods to learn more about contacts. Buy using different kinds of ultrasonic waves, transducer topologies, and signal processing we will develop methods to measure contact load, stress history, oil viscosity, and friction. These will be prototyped in the laboratory and we have industrial partners ready to provide field applications. In addition the fellowship seeks to collaborate with academic institutions; firstly to learn new acoustic sensor techniques and secondly to support research into machine element research with the provision of new measurement methods.This will support the Leonardo Centre aim to be, not only the leading centre for ultrasonic measurement in tribology, but to be a key part of the UK's research infrastructure in machine component research and development both in industry and academia.