Abstract: A method of detecting a vibration node between a non-collocated sensor-actuator pair of a rotatable component includes applying an excitation signal to an actuator of the sensor actuator pair. The method also includes obtaining frequency response data from the sensor-actuator pair. The method further includes analyzing the frequency response data to ascertain a resonant frequency of the rotatable component. The method includes identifying a resonance/anti-resonance peak pair in the frequency response data for the non-collocated sensor-actuator pair. Furthermore, the method includes determining whether the vibration node is located between a sensor and the actuator of the non-collocated sensor-actuator pair based on the resonance/anti-resonance peak pair.

Abstract: A security dye pack disguised as a bundle of currency for deterring robberies includes a housing formed from a stack of currency bills sewn together and having a hallow chamber formed therein. A substrate disposed within the chamber has a flexible central region through which electrical conductors extend for making electrical interconnections between opposing ends of the substrate. Electrical components are mounted on both sides of the flexible central region to generate an actuating signal upon detecting removal of the security dye pack from the protected premises. Canisters containing dye or other active chemicals are secured at opposing ends of the substrate to emit dyed or other active chemicals in opposing directions when expended. The flexible central region of the substrate allows the security dye pack to be bent into a U-shape. Batteries are arranged in a side-by-side relationship in an elongated narrow case to facilitate bending of the security dye pack.

Abstract: An apparatus for detecting machining conditions in a machine tool has a magnetic bearing for magnetically supporting a work spindle or a tool spindle. An exciting current detector is provided for detecting an exciting current of an electromagnet of the magnetic bearing. The exciting current corresponds to various machining conditions including the conditions when the machine tool starts operating, the tool contacts the workpiece to follow various unfinished faces, and a machining face condition of the workpiece during machining. The detection signals from the exciting current detector are inputted to a plurality of frequency band pass filters to discriminate the machining conditions. Comparators are provided to compare the output signals from the frequency band pass filters with a predetermined set of reference values, and comparative judgment signals are inputted to a control unit, thereby controlling the machine tool to automatically perform appropriate machining operations.