Angular approach combined to mechanical model for tool breakage detection by eddy current sensors

Mathieu Ritou (1) , Sébastien Garnier (1) , Benoît Furet (1) , Jean-Yves Hascoët (1)

1 Modélisation et Optimisation de Process de Production (MO2P)

The paper presents a new complete approach for Tool Condition Monitoring (TCM) in milling. The aim is the early detection of small damages so that catastrophic tool failures are prevented. A versatile in-process monitoring system is introduced for reliability concerns. The tool condition is determined by estimates of the radial eccentricity of the teeth. An adequate criterion is proposed combining mechanical model of milling and angular approach. Then, a new solution is proposed for the estimate of cutting force using eddy current sensors implemented close to spindle nose. Signals are analysed in the angular domain, notably by synchronous averaging technique. Phase shifts induced by changes of machining direction are compensated. Results are compared with cutting forces measured with a dynamometer table. The proposed method is implemented in an industrial case of pocket machining operation. One of the cutting edges has been slightly damaged during the machining, as shown by a direct measurement of the tool. A control chart is established with the estimates of cutter eccentricity obtained during the machining from the eddy current sensors signals. Efficiency and reliability of the method is demonstrated by a successful detection of the damage.

Mots clés: Tool Condition Monitoring; Cutting force model; Milling; Eddy current sensor; synchronous average

Domaines: Génie mécanique [physics.class-ph]; Génie mécanique [physics.class-ph]

Mathieu Ritou, Sébastien Garnier, Benoît Furet, Jean-Yves Hascoët. Angular approach combined to mechanical model for tool breakage detection by eddy current sensors. Mechanical Systems and Signal Processing, 2014, 44 (1-2), pp.211-220. ⟨10.1016/j.ymssp.2013.02.004⟩. ⟨hal-00862232⟩