VERFAHREN UND VORRICHTUNG ZUR REDUZIERUNG VON SCHWINGUNGEN

摘要

A method of reducing unwanted vibrations in a zone wherein such unwanted vibrations arise from a source of vibration, which generates a signal having at least one vibrational component at a substantially constant frequency over a detection period, the method including within a detection period deriving a tracking signal at the constant frequency; providing in-phase and quadrature components I, Q of the tracking signal; monitoring vibrations at each of a plurality of predetermined locations within the zone to provide a set of observation signals 6; multiplying each of said in-phase and quadrature components I, Q of said tracking signal by each of said observation signals 6 and filtering each resultant to provide a set of output values Iout. Qout, each of which represents the extent to which the respective observation signal 6 contains vibrations at the constant frequency; and utilising the set of output values Iout, Qout and the in-phase and quadrature components of the tracking signals I, O to produce a plurality of drive signals 8 which when supplied respectively to each of a plurality of actuators cause vibrations to be produced within the zone which tend to cancel those generated by the vibration source. The method is particularly useful in propeller-driven aircraft. <IMAGE>