Fibre based low coherence interferometry for in-process control of electrochemical machining processes

制造过程的现场控制和在线监控是复杂且难以实施的。例如，制造过程通常是快节奏的，这意味着任何实时监控系统都必须灵活，能够足够快地分析数据以实施决策。此外，制造环境是不理想的，随着时间的推移，各种外部因素会影响系统的状态。在电解加工中尤其如此，电解加工是在电解液中进行的，或者在电解液喷射加工的情况下在电解液的小射流中进行。在这种环境下，在紧凑的工艺操作空间内进行高精度测量是具有挑战性的，目前还没有可用的测量技术来实现这一点。低相干干涉测量是一种很有前途的技术，它利用光来捕获系统内的距离信息。光可以从光端光纤部署，并允许从高度空间受限的环境中捕获数据。然而，如果使用光纤而不添加光学元件，传感器的性能将大大降低。当前的系统受到确保精确测量所需的距离和使用的光源类型的限制。此外，系统还受限于其在制造机械中的操作、性能、成本和包装。本研究的目的是：分析现有的OCT干涉测量系统，以了解它们在具有挑战性的制造过程中应用于原位测量时的局限性。作为EPSRC拨款EP/ m020746 /1的一部分，支持现有原型系统的进一步开发和扩展操作，开发一种方法来延长距离，从而延长工作范围。开发一种数据收集和分析方法，使连续扫描方法能够用于扩展操作。

In-situ control and in-line monitoring of manufacturing processes are complex and difficult to implement. For example, manufacturing processes are often fast paced, meaning any real-time monitoring system must be flexible and able to analyse data quickly enough to implement decisions. In addition, manufacturing environments are non-ideal with varying external factors affecting the state of the system with time. This is especially true in electrochemical machining, which takes place within a bath electrolyte liquid, or within a small jet of electrolyte, in the case of electrolyte jet machining. Making high precision measurements in this environment, and within the compact operating space of the processes, is challenging and currently there is no available measurement technologies to achieve this. Low coherence interferometry is an established promising technique, which uses light to capture distance information within a system. It is possible to deploy the light from a bare tipped fibre optic and allowing data to be captured from highly space constrained environments. However, which using a fibre without the addition of optics, the performance of the sensor is greatly reduced. Current systems are limited by the standoff distance required to ensure accurate measurements are possible and the type of light source used. In addition, systems are limited by their operation, performance, cost and packaging within the manufacturing machinery. The purpose of this research will be to:Analyse existing OCT interferometry systems to understand their limits when applied to in-situ measurements in challenging manufacturing processes. Support the further development and extend the operation of the current prototype system created as part of EPSRC grant EP/M020746/1Develop an approach to extend the standoff distance and, as such, the working rangeDevelop a data collection and analysis methodology to allow continuous scanning methods to be used for extended operation.