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Proceedings of the International Conference on
Advances and New Challenges in Earthquake
Engineering Research, Hong Kong Volume
STRUCTURAL VIBRATION CONTROL USING PIEZOCERAMIC
PATCH ACTUATOR
G. Song 'and B. Xie
Smart Materials & Structures Laboratory
Department of Mechanical Engineering
The University of Akron,
Akron, OH 44325-3903 USA
ABSTRACT
This paper presents active vibration control of a 3-floor model building using piezoceramic patch
actuators. Piezoceramic material possesses the property of piezoelectricity, which describes the
phenomenon of generating an electric charge in a material when subjected to a mechanical stress (direct
effect), and conversely, generating a mechanical strain in response to an applied electric field. This
property prepares piezoceramic materials being able to function as both sensors and actuators. The
advantages of piezoceramic include high efficiency, no moving parts, fast response, and being compact. A
commonly used piezoceramic is the Lead zirconate titanate (PZT), which has a strong piezoeffect. PZT
actuation strain can be on the order of 1000 £i strain. Within the linear range, PZT actuators produce
strains that are proportional to the applied electric field/voltage. These features make them attractive for
dynamic applications. PZT can be fabricated into different shapes to meet specific geometric
requirements. PZT patches are often used as both sensors and actuators, which can be surface-bonded to
various structures. In the research, surface-bonded PZT patches are used as both sensor and actuators.
Prior to control design, experimental modal testing of the model building is performed to reveal the
dominant modes and their corresponding modal shapes. This information is then used in the control
design. Several controllers, positive position feedback, strain rate feedback, and sliding-mode control, are
designed and implemented on the 3-floor model building. Increased vibration damping is observed in all
control designs. A comparative study is conducted to reveal the advantages and disadvantages of each
control design.
1 INTRODUCTION
Recent years have seen the emergence of the new field of structural control "smart structure" or "active
structure" for application to active control of seismic-excited linear and nonlinear civil engineering
structures. The term of "smart structure" or "active structure" is uses to describe a structure, which has the
ability to sense and adapt to the changing operational condition according to the designed specifications.
Smart structures are characterized by integrating sensors, actuators and micro-processors. Among the
smart materials used in the smart structures, piezoceramics has proven to be one of the most promising
ones in the active control applications. The advantages of piezoceramic include high efficiency, no
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