Kv=141-position loop gain [1/s],visionair-browser.g-scop.grenoble-inp.fr/visionair... · Web viewFig.5 Visualisation of the whole CNC portal milling machine in machine EON Studio

Project funded by the European Commission under grant agreement n°262044

PUT-Poznan: TNA-Project-159- Modeling of CNC milling machine feed drive in Matlab-Simulink and its visualization in Virtual Reality

Proposer: Prof. Dr. Zoran PANDILOV, University "Sv. Kiril i Metodij"-Skopje, Faculty of Mechanical Engineering, Republic of Macedonia

Visited institutions: Department of Mechatronic Devices and Virtual Reality Laboratory at Poznan University of Technology, Poland

Visit Dates: 02.06.2014-02.07.2014

During my research stay I was hosting by professor Dr. hab. inż. Andrzej Milecki and his research team: Mgr inż. Amadeusz Nowak, mgr inż. Damian Grajewski and Dr. inż. Filip Górski. The research was very complex and divided in two phases.

The first phase was modelling of the very complex models of the portal 3-axis CNC milling machine feed drives which consist of many elements (position, velocity and current control regulators, actuators, mechanical transmission elements, etc.). All these elements have great influence on the machine tool important parameters like movement stability, positioning accuracy and dynamic stiffness. The modeling was done with Matlab-SIMULINK and Sim Scape. The Sim Scape Toolbox allowed us to use the complete CAD model of the geometry of the machine tool in modeling and automatically calculating the selected properties.

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Fig. 1 CAD model of the machine tool Fig. 2 Simulink model of position and velocity loop for one axis feed drive

The influence of changing and optimization of several feed drives parameters (position loop gain Kv, proportional gain Kp of the velocity controller, integral gain of velocity controller-Tn, electrical drive time constant Te, total moving mass m, sampling period Ts, etc.) on positioning accuracy and dynamic stiffness were simulated, tested and validated.

The ready Matlab-Simulink and Sim Scape models were initially visualized in the Matlab program, but they were very simplified, comparing their visualization in Virtual Reality EON Studio program.

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Fig. 3 Sim Scape model of mechanical elements of y-axis of portal CNC machine tool1

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Fig 4. Complete model of CNC portal machine tool feed drives (x, y and z axis) with simple visualisation in SIMULINK

The second phase of the research was visualization of the whole machine tool using the CAD model of machine tool and models of the feed drives developed in Matlab-Simulink and Sim Scape in Virtual Reality system with EON Studio software. The using of EON software significantly improved the model and visualization quality.

With the visualization we were able to simulate the real work of the whole CNC machine tool (contouring operations, changing tools, etc.)

Fig.5 Visualisation of the whole CNC portal milling machine in machine EON Studio software

Fig.6 Presentation of the finished project

This whole research could be very useful to machine tool producers, because they could change their practice of making very expensive real prototypes of the CNC machine tools, with creating virtual prototypes of machines.

Leaving the Poznan University of Technology, Department of Mechatronic Devices, I am deeply convinced, that my finished TNA VISIONAIR project, will be only a start of a long term collaboration in research, scientific and educational issues with my host institution and host institution colleagues.

Proposer of the project: Host: Prof. Dr. Zoran PANDILOV Prof. Dr. hab. inż. Andrzej MILECKI