Blade tip timing-based blade vibration measurement technology and its applications to aeroengine: A systematic review

Blade tip timing (BTT) is a critical non-contact measurement technology for monitoring blade dynamics in rotating machinery, primarily due to its excellent ability to provide accurate, real-time data for all blades without interfering with blade structure or flow field. Driven by the demand for high-speed, high-precision monitoring in advanced aeroengines, the BTT technology is developing rapidly in the design and optimization of measurement systems, signal processing algorithms, and engineering applications in structural monitoring. To further enhance the applicability and reliability of the BTT in the complex operating environments of aeroengines, researchers have undertaken improvements and optimizations of the BTT technology from multiple perspectives. This paper presents a state-of-the-art review of the recent advancements in the BTT technology. Firstly, it briefly outlines the theoretical foundations of the BTT, followed by an assessment of its development trends. Secondly, five popular sensors for BTT measurement are presented. Particularly, optimization strategies related to the sensor placement and number of sensors are comprehensively reviewed. Thirdly, BTT signal processing methods are summarized, including their fundamental identifying principles of vibration characteristics parameters, strengths, and limitations. Additionally, special attention is given to the errors and uncertainties in BTT measurements. Then, various applications of the BTT in structural monitoring are reviewed. Finally, comments on the latest research progress are made, and outlooks on future research directions are highlighted. This review aims to provide researchers in this field with a timely, comprehensive, and systematic reference on the BTT technology, and to offer theoretical support to foster further innovation and application of this technology.