|
Piezoelectric
Sensoriactuator Circuit for Passive Vibration Damping
Passive
vibration control techniques, such as tuned proof mass absorbers,
have proven a reliable alternative to more expensive active
systems, offering the benefits of stability and performance
without the use of complicated electronics and bulky amplifiers.
Most importantly, the inherent quality of unparalleled
robustness make passive control techniques most desirable for a
variety of systems. Another
beneficial characteristic of dynamic systems is collocation.
The sensoriactuator by its very nature is a collocated
sensor/actuator. Collocation
further enhances the stability characteristics of the system in
which it is used.
It
has been shown that passive electronic damping can be successfully
achieved using tuned RL circuits to shunt piezoelectric materials
on structures. These
designs provide electronic equivalents of tuned-vibration dampers
where the coupling coefficient plays the role of the mass ratio in
similar mechanical devices and is the primary factor in
determining performance. However,
in many applications the coupling coefficient is too small to
produce desired or acceptable changes in performance.
In addition, changes in system parameters, such as the
piezoelectric's capacitance, detune the system also limiting
performance.
A
sensoriactuator circuit offers the ability to eliminate the
effects of the piezoelectric's capacitance and improve the
coupling coefficient. Thus,
electronic dampers built with a sensoriactuator circuit offer
improved performance over their strictly passive counterparts.
A
cantilevered beam experimental test article is used with a
sensoriactuator circuit attached.
The sensoriactuator and appropriate control filter are used
in place of the passive shunt circuitry.
The sensoriactuator is placed to attenuate the response of
a single mode. An
optimal circuit design criteria somewhat analogous to that of the
resonant shunt damper is under investigation.
View
of cantilevered beam test rig with sensoriactuator attached
This work was generously
supported by GOALI/Lord Corporation # CMS 9908271.
Research
performed by Matthew V. Kozlowski
and Robert L.
Clark.
Contact
the webmaster.
|