Abstract: A device and method for the non-contact measurement of dynamic torsion in a rotating shaft using magnetostrictive sensors (MsS). The monitoring and detection system has specially configured magnetostrictive signal detectors that include inductive pick-up coils, in which signals corresponding to localized shaft torques are induced. The basic system sensor utilizes either a permanent DC bias magnet positioned adjacent the rotating shaft or applies a residual magnetic field to the shaft. The techniques described in conjunction with the system are particularly advantageous for on-line monitoring of loaded rotating shafts that are integral parts of power trains, by providing a low-cost and a long-term sensor for acquiring dynamic data of the shaft portion of the machinery system being monitored and/or controlled.

Abstract: A method and apparatus is provided for the sensing, collection, and analysis of information on combustive and mechanical events occurring within an operating internal combustion engine through the measurement of mechanical stress waves present within the engine. The system includes a magnetostrictive sensor placed in mechanical compliance with the engine, preferably the engine block, which detects and translates stress waves into an electrical signal that is filtered and amplified for recording and/or for analysis. Information regarding the frequency, amplitude, and timing changes within the signal is utilized to characterize the ordinary operation of the engine and to identify anomalous events. The system includes a means for maintaining a signal record and comparing signal features with past records for a particular engine or with standard signal features associated generally with certain engine events.