Study of a sensor platform for monitoring machining of aluminium and steel

Being able to measure and monitor the forces applied and the resulting vibrations is important to be able to understand and control the process of milling, which is a highly interrupted process based on many variables. The present work concerns analysis of signals gathered during shoulder milling of toughened steel 2541-3 and aluminium alloy 7010. The signals acquired are force in three dimensions and accelerometer in the two horizontal dimensions. Moreover, a laser Doppler vibrometer is applied. The correlations of the analysed signals of the different sensors with the surface roughness were studied. While the signal stability and correlation were unsatisfactory for several sensors, the three sensors measuring along the feed direction were most suitable to monitor the increase of the machined surface roughness with increasing feed rate.