The Expert system FatiDamage has been developed for evaluating the fatigue crack
initiation life of the machinery and structural components. The system comprises three
major modules: fatigue character evaluation system, fatigue load evaluation system and
fatigue life prediction system. The predictability of the expert system has been examined
by comparing the predicted fatigue lives with experimental one. The system has been
implemented using the UNIK expert system shell, Visual FoxPro database software and
Borland C++.Rules and frames have been used for the knowledge expression and forward
chaining has been adopted for inferring the knowledge.
Fatigue properties of the material can be estimated from tensile test data using the
best estimation method recommended by the expert system. Users can confirm the applied
method and update the knowledge for the predictabilities of the estimation methods with
the experimental results. The Unified method has been suggested and adopted with
default in the expert system for fatigue damage evaluation.
The predictability of the expert system based on the prediction results in compare
with the SAE fatigue experimental data are about 81.4%. Using the expert system, general
users such as mechanical designer can get the available results considering of the load
interaction effects.
