The model represents a stator in an ultrasonic motor. Voltage fluctuations applied to the PZT material attached to the base of the stator induce vertical motions of the stator which eventually result in a traveling wave around its perimeter. The implicit transient dynamics procedure is used to examine the initial transients, which then evolve into a steady traveling wave.
Description
Piezoelectric-Mechanical interaction refers to a coupling between structural distortion and electric potential. Materials that exhibit this effect are called piezoelectric materials and have additional material properties linking electric flow to local structural distortion. These materials have many applications in accelerometers, MEMS devices, medical surgical equipment, control devices and other applications where shape control through electrical means is desired.
Abaqus contains a complete two-way electrostatic Piezoelectric-Mechanical simulation capability allowing electric flow to cause straining in the material (and shape change) and also allowing stress to cause electric potential change.
Abaqus capabilities
Piezoelectric elements can be used in general analysis steps, including both geometrically linear and nonlinear analyses (in nonlinear analysis, however, the piezoelectric constitutive response remains linear).
Static and transient dynamic procedures can be used to solve piezoelectric problems.
A linear perturbation analysis (about a nonlinear base state) can also be performed (e.g., one can extract the frequencies and mode shapes about a statically preloaded state)
Resources:
Elhadrouz, M., Zineb, T., and Patoor, E., Ecole Nationale Supérieure d'Arts et Méties, "Implementation of a Constitutive Law for Ferroelectric and Ferroelastic Piezoceramics Using the Subroutine User Element (UEL)," ABAQUS Users' Conference, Stockholm, Sweden, May 2005, pp. 127 - 141.
Mahoney, J. F., AlliedSignal, Inc., "Modeling and Simulation of Miniature Piezoelectric Motors," ABAQUS Users' Conference Newport, Rhode Island, May 1998, pp. 489 - 503. KEYWORDS: Eigenvalue extraction, VUMAT, actuators
Ultrasonic motors can be extremely efficient when used in micro-devices. The drive for these motors is typically a stator made from a piezoelectric material which provides mechanical force when an electrical current is applied. Optimal design of these motors present many challenges including extensive use of mechanical moving parts and PZT elements, high torque, etc.
Solution
The Mutiphysics solution from SIMULIA allows the engineer to evaluate the performance and response of the motor under both static and dynamic conditions, taking into account critical nonlinear effects. This provides a realistic assessment of the motor's performance against a prescribed set of design criteria.
By performing sophisticated finite element analysis, design and performance issues are addressed prior to prototype production and testing. This reduces development cost and time-to-market and provides for a more reliable product.