Model trees and sequential minimal optimization based support vector machine models for estimating minimum surface roughness value

Average surface roughness value (Ra) is an important measure of the quality of a machined work piece. Lower the Ra value, the higher is the work piece quality and vice versa. It is therefore desirable to develop mathematical models that can predict the minimal Ra value and the associated machining conditions that can lead to this value. In this paper, real experimental data from an end milling process is used to develop models for predicating minimum Ra value. Two techniques, model tree and sequential minimal optimization based support vector machine, which have not been used before to model surface roughness, were applied to the training data to build prediction models. The developed models were then applied to the test data to determine minimum Ra value. Results indicate that both techniques reduced the minimum Ra value of experimental data by 4.2% and 2.1% respectively. Model trees are found to be better than other approaches in predicting minimum Ra value.