文档介绍：Time Effective Transient Analysis Using ANSYS
Mechanical and Matlab Simulink
Jan Rubacek
Philips Oral HealthCare

Abstract
The performance of the Elite® advanced resonant power toothbrush is measured in terms of oral biofilm
removal and improvements in oral health over time. These are strongly related to the mechanical
performance of the brush head and bristles located on it. To find an optimum resonant structure, which
provides both the required performance and a specified clinical experience, the transient behavior of the
toothbrush is modeled.
To optimize the resonant structure, we are using an APDL built FEM model. Using this model we are
able to perform Modal, Harmonic or Transient analysis within ANSYS Mechanical (Release ). To save
time and expense, the dynamics of the brush head are calculated by using a modal analysis in FEM, and
exported as eigen vectors to Matlab. In Matlab this data is translated to a state-space formulation and used
as a transfer function of a linear system in Matlab Simulink. This allows us to apply various excitations and
look at time domain responses of our power toothbrush.
Introduction
To evaluate the toothbrush response in time domain, one needs to do a transient dynamic analysis. ANSYS
offers three methods of transient dynamic analysis: Full transient, Modal superposition method, and
Reduced method. These methods differ in calculation method, and also in range of applicable types of load.
In this paper pare our results from ANSYS with transient calculations done in Matlab Simulink.
When using ANSYS for transient analysis, we have faced the following issues, which make our analysis
plex:
1. Input signal definition:
Tabular input requires pre- data processing in excel versus a direct loading from the measurement. For
simple waveforms the ANSYS tabular format was sufficient.
2. Time of calculation:
There is significant difference in calculation time between ANSYS tran