NOISE REDUCTION IN A MEDICAL IMAGING INSTRUMENT USING DISTRIBUTED PIEZOELECTRIC ACTUATOR/SENSOR BASED ON THE FEM MODELING

The purpose of this paper is reducing mechanical noise in a Magnetic Resonance Imaging (MRI) set. The vibration suppression in this instrument prevents the test results to be damaged, which is an important issue in medical tests. For this aim, the task of the structure modeling is tackled using the FEM approach and first order modal identification from the measured input-output data. The space model has been obtained from the dynamic frequency response of the modeled structure. The control problem of the funnel shaped structure is considered using LQG control method. Complete design and control development procedure is implemented in order to reduce the vibration magnitude of a funnel-shaped shell structure of the magnetic resonance tomography used in medical diagnostics.

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