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International audience; This article presents a work in progress of using augmented reality as a way to help handling computer numerical control (CNC) machine tools. Several reasons justify the use of augmented reality in machine tools: (i) a high complexity of using such machines, especially for beginners; (ii) low ergonomics since the operator has to move continuously between the machine window and a control screen to ensure smooth operations; (iii) the window is often obstructed by the lubricant, therefore the operator must often rely only on information displayed by the control screen; (iv) a non-user-friendly interface of the machine; and (v) a complex maintenance operation.In this work, a prototype of a system allowing an operator to improve its working conditions and better handle CNC machines using ar devices is proposed. These devices are positioned in front of the machine, connect to it and display real-time information, such as the operating conditions and a 3D representation of the cutting tool motion. A user interface was also designed to manage operators’ profiles with customized information. The system was tested by several users who confirmed its potentialities to assist machine operators in their work. Other possibilities of this system are under investigation, such as a training tool for beginners and a guide for machine maintenance.

National audience; Le but de cet article est d’étudier l’influence des paramètres de coupe sur la formation des bavures en coupe orthogonale. Pour ce faire, une étude en rabotage est réalisée avec des plaquettes carbures, sur un alliage d’Aluminium-Silicium, communément utilisé pour la fonte de culasses automobiles. Cette étude consiste à analyser l’influence de différents paramètres de coupe sur la formation des bavures dans le matériau. Les résultats obtenus permettent de conclure sur l’influence de certains paramètres de coupe sur la formation de la bavure, ainsi que son caractère aléatoire en coupe orthogonale, dû à l’hétérogénéité du matériau.

International audience; Burr formation during parts manufacturing is a significant problem that companies try to minimise or eliminate. The present work aims to study the burr formation mechanisms in a cast aluminium alloy. Orthogonal cutting tests are performed using different uncut chip thicknesses and tool rake angles. To analyse burr formation mechanisms, the work material state of stress and triaxiality distribution in the chip root was investigated via numerical simulations. Results show that the uncut chip thickness has an effect on burr morphology and burr cumulation while tool rake angle influences burr height on high uncut chip thicknesses.

International audience; Force modelling is a major research topic in machining. Several approaches are used to face with the different needs. Mechanistic models appear to be an easier and rapid way for computing cutting forces; nevertheless they may suffer from accuracy and physically meaning. This article is presenting an advanced mechanistic cutting force model for turning on Ti6Al4V alloy. It considers the effect of the chip flow direction on cutting forces. The proposed model is compared to a basic one and demonstrates its ability to predict more accurately the feed force and the penetration force, which are usually difficult to evaluate.

Colloque avec actes et comité de lecture. Internationale.; International audience; Dans le but de valider les simulations de la coupe visant à prédire l'intégrité de surface, une instrumentation basée sur une caméra double-frame et un éclairage laser pulsé a été développée. A partir des doublets d'images obtenus par ce moyen d'acquisition, les dépouillements possibles par corrélation d'images sont détaillés, accompagnés d'estimations d'incertitudes de mesure.