Active Vibration Suppression of a Cantilever and Sound Pressure Control of a Loudspeaker Using a PVDF Sensor
Date Issued
2009
Date
2009
Author(s)
Pan, Shan-Ying
Abstract
In many industrial, scientific and defence applications, the presence of noise and vibration is of major concern. In the first part of this thesis, a polyvinylidene fluoride (PVDF) film sensor is applied to measure the vibration of a cantilever beam system. Based on these signals of the PVDF sensor, the first three modes of this beam system are suppressed via four kinds of feedback controllers. These controllers are positive position feedback (PPF) controller, resonant controller, constant gain controller, and integral controller. By using Simulink modules, optimum parameters are calculated and applied to this cantilever beam system. In the second part of this thesis, the PPF controller is chosen to suppress a panel loud speaker unit. The characteristic of the sound pressure level (SPL) curve of this speaker unit is predicted via the measuring procedure mentioned above. The SPL curve can be modulated by suppressing the vibration of the loudspeaker structure. In the final part, these simulated and experimental results address a new direction of modulating SPL curve of a loudspeaker unit.
Subjects
PVDF film sensor
cantilever beam
vibration control
PPF controller
resonant controller
constant gain controller
integral controller
Type
thesis