Characterization and Control of Non-Steady State Machine Vibration

在从风力涡轮机到飞机的各种机械中，非稳态运行条件是很常见的。然而，这些情况下的系统反应动力学仍然没有得到很好的描述，也没有得到很好的理解。产生非稳态响应的不断变化的运行条件是由多种因素引起的，例如不可预测的机器速度(风力涡轮机中的行星齿轮系统)、波动的质量(采矿斗的装载和排空)或可变激励(飞机飞行包络、核磁共振扫描仪成像激励)。在所有情况下，为了控制机械振动和减轻潜在的有害影响，充分了解系统响应是极其重要的。广泛的非稳态机器响应应用具有定义不同运行机制的广泛且可变的时间范围(可能从几分钟到几个月)。定义这些系统运行条件的许多不同参数也可能以不可预测的方式组合在一起。在这些情况下，表征、预测和控制机械振动仍然具有挑战性。到目前为止，非稳态系统的表征遵循了一条特别的发展道路。大多数工作都集中在非稳态系统行为是独特的特定应用上。拟议的研究工作将采用更有条理的方法。这种方法将从一组传统上用于稳态系统识别和表征的表征标准开始，并开发用于表征非稳态运行的新的和/或混合方法。我和其他人的初步工作揭示了在这方面显示出重大前景的几种新的信号分析方法。最近的研究已经开始生产允许系统状态监测、故障诊断、振动控制和系统性能优化的工具。这项工作的大部分需要固定的时间尺度、预期的系统运行状况的先验知识以及代表这些运行状况的样本数据的合理历史。我过去的研究工作与这一研究领域直接相关，重点是不需要详细的先前系统知识也不需要样本数据来训练分析算法的方法。我最近完成的其他密切相关的工作包括减少核磁共振扫描仪的噪音和振动，以及控制采矿机的振动。这两种应用中的振动和噪声问题的解决依赖于对系统在非稳态运行情况下的性能有更清晰的了解。在我的Discovery Grant申请中提出的研究工作将集中在通过系统表征进一步了解非稳态系统性能。研究成果的应用将直接为机械/结构状态监测、故障检测与诊断、振动控制、系统性能与设计优化提供新的方法。在我的研究计划中，我将把重点放在这些成果的应用上，因为它们适用于行星变速箱的故障检测和诊断、核磁共振扫描仪的降噪以及采矿跳汰机的振动控制。虽然这些应用可能看起来相对具体，但它们有共同的方面，代表了加拿大一系列以资源为基础的重要行业感兴趣的广泛研究领域。我的专业知识和经验使我独一无二地能够解决这些问题。

Non-steady state operating conditions are commonplace in a wide range of machinery from wind turbines to airplanes. However the system response dynamics in these situations remain poorly characterized and not well understood. The changing operating conditions that generate non-steady state responses are due to a variety of factors such as unpredictable machine speed (planetary gear systems in wind turbines), fluctuating mass (loading and emptying of mining skips) or variable excitation (aircraft flight envelopes, MRI scanner imaging excitation). In all cases it is extremely important to fully understand the system response in order to control mechanical vibration and mitigate potentially harmful effects. The broad class of non-steady state machine response applications has a wide and variable time scale (potentially ranging from minutes to months) defining the different operational regimes. The many different parameters that define the operating conditions of these systems may also combine in unpredictable ways. In these cases it remains challenging to characterize, predict and control the mechanical vibration. Non-steady state system characterization has followed an ad-hoc development path to date. Most work has focused on particular applications where the non-steady state system behaviour is unique. A more structured approach will be followed in the proposed research work. This approach will begin with a set of characterization criteria that are traditionally used in steady state system identification and characterization and develop new and/or hybrid methods for characterization of non-steady state operation. Preliminary work by myself and others has revealed several new signal analysis methods that show significant promise in this regard. Recent research has begun to produce tools that allow system condition monitoring, fault diagnosis, vibration control and system performance optimization. Most of this work requires fixed time scales, prior knowledge of the expected system operating conditions and a reasonable history of sample data representing those operating conditions. My past research work has been directly related to this research area and was focused on methods that do not require detailed prior system knowledge nor sample data for training of analysis algorithms. Other closely related work that I have completed recently includes noise and vibration reduction in MRI scanners and vibration control in mining skips. Solutions to the vibration and noise problems in both of these applications relied on development of a clearer understanding of the system performance during non-steady state operational situations. The research work proposed in my Discovery Grant application will be focused on the further understanding of non-steady state system performance through system characterization. Application of the results of this work will lead directly to new methods for machine/structure condition monitoring, fault detection and diagnosis, vibration control, and system performance and design optimization. In my research program I will be focusing on the application of these results as they apply to fault detection and diagnosis in planetary gearboxes, noise reduction in MRI scanners and vibration control in mining skips. While these applications may seem relatively specific they have common aspects and represent a broad field of study of interest to a range of important resource based industries in Canada. My expertise and experience uniquely position me to address these topics.