Maher Barkallah

Modeling and Simulation of Micro EDM Process

In contrast to Robust Design applications, the simulation of a mechatronic system including both mechanical and electrical parts requires a different strategy for the investigation of its robustness. Differences mainly results from interactions between the mechanical and the electrical part of the mechatronic system. Micro Electrical Discharge Machining (μEDM) is good example for mechatronics application. This paper presents an approach to evaluate robustness of mechatronic comfort systems. At the outset, this study revolves around modeling of the various constitutive blocs of the machine through the appliance of the ‘Matlab/Simulink’ as well as analyzing the strength of this model by resorting to the same software programme of simulation . Having gone through the phase of simulation, the main outcomes of this experience where noticed at the level of the parameters defining the drilling such as the gap and the position of the electrode.

Analytical Based Approach for Vibration Analysis in Modelica: Application to the Bridge Crane System

Most engineering system, machines and products have moving parts and in order to achieve a desired performance, they require the manipulation of their mechanical or dynamic behavior from the early stage of design. Also, the dynamic interaction between the moving object and the structure should be properly considered at this level. The objective of the presented paper is to propose a new methodology for the pre-design of a mechatronic system, considering the vibrational behavior using the object oriented modeling language Modelica with Dymola environment. In fact, we study the dynamic behavior of a supporting flexible beam structure (simply supported at both ends) traversed by moving masses at variable speeds, based on the object-oriented modelling paradigm developed in Modelica. An analytical approach is adopted, providing a compromise between the results accuracy and the computation time. To illustrate the methodology, the bridge crane system is used as a supporting study. This machine is commonly used in industrial facilities. The effects of varying the different parameters on the dynamic response of the system are investigated. This methodology would be useful for a designer to have an overview about the system response and the interaction between the different subcomponents in the conceptual design phase.

A SysML based-methodology for modelling disturbances in manufacturing systems using ADACOR holonic control architecture

Nowadays, industrials are looking for models and methods that are not only capable to support efficient production performances, but also reactive systems facing an increasing set of unpredicted events and perturbations. For this reason, manufacturing control systems must include mechanisms that cope with the complexity and unpredictability related with disturbances and perturbations that may appear in the system. In this paper we propose a methodology based on SysML language and holonic architecture “ADACOR” for modelling the sources of disturbance and its management in manufacturing systems. In the proposed methodology we show how we use SysML diagrams to estimate the future performances in a reactive mode and how to switch between the scheduling and control in the case of unpredictability. In order to validate the proposed methodology, a case study has been conducted on a welding cell. As a result, we noticed that the unpredictable events are controlled in such a way that we assure a continuous production.

Non-linear Stiffness and Damping Coefficients Effect on a High Speed AMB Spindle in Peripheral Milling

During the milling operation, some factors such as the cutting parameters and the spindle type and speed can influence the cutting force attitude consequently the state of the finished part. In this work, a High Speed Milling (HSM) spindle supported by a pair of Active Magnetic Bearings (AMB) is modeled. The shaft is discretized with Timoshenko beam finites elements. The six degrees of freedom of both rigid and elastic motions are considered. Electromagnetic forces are modeled by linear springs and dampers. A peripheral milling model is suggested to predict the dynamic cutting force and the tool tip response. Dynamic coefficients of bearings with four, six and eight electromagnets are considered and plotted to study the spindle dynamic behavior.