SBIR-STTR Award

AI Signal Research, Inc. proposes to develop a Non-Intrusive Vibration Measurement System (NI-VMS) for turbopumps which will provide effective on-board/off-board fault detection diagnostic capabilities without relying on any intrusive installation of once per revolution (1/Rev) tachometer key phasor measurement. Many vibration signature analysis techniques use a key phasor signal to identify and detect critical vibration characteristics and fault signatures. However, in many operational environments (e.g., SSME HPOTP), the tachometer measurement is not available usually due to its intrusive installation requirement or safety consideration. For this situation, many powerful diagnostic analyses cannot be performed. With our system, we over come this problem by utilizing a novel signal analysis technique called Pseudo Key Phasor (PKP) to reconstruct an equivalent 1/Rev PKP signal directly from a non-intrusive vibration measurement. The resulting PKP signal enables the use of effective signature analysis to enhance diagnostic capabilities. The applicable innovation is attributed to to effectively achieve non-intrusive health monitoring and diagnosis without intrusive tachometer installation. This technology will enhance incipient fault detection capability, reducing catastrophic engine failure risks and improve reliability of NASA's advanced propulsion systems. Phase I objectives are to demonstrate the feasibility and relative benefits of NI-VMS non-intrusive monitoring capabilities.

ASRI proposes to develop an advanced and commercially viable Non-Intrusive Vibration Monitoring System (NI-VMS) which can provide effective on-line/off-line engine vibration monitoring capabilities without relying on intrusive key-phasor speed measurements. Many powerful vibration signature analysis techniques for engine-health monitoring rely on key-phasor signals to extract/enhance critical fault signatures from noisy vibration measurements. In many situations (e.g. SSME HPOTP), such speed measurements are not available, usually due to the safety concerns of a key-phasor's intrusive installation (e.g.in a high-pressure liquid-oxygen environment for HPOTP). As a result, the ability/reliability for health monitoring and post-test diagnostic evaluation is severely limited. The proposed NI-VMS overcomes this problem by utilizing a novel signal analysis technique called Pseudo Key Phasor (PKP) to reconstruct a PKP signal directly from external vibration measurements. This procedure enables powerful signal analyses that require a key phasor to become applicable, greatly enhancing fault detection and diagnostic capabilities. NI-VMS can reduce the risks of catastrophic engine failure and improve the reliability of NASA's current/future propulsion systems. Phase I feasibility studies using SSME test data have successfully demonstrated the technical merits of NI-VMS. Phase II will complete design, development, and testing of the prototype NI-VMS hardware/software system.