한국정밀공학회 2013 년도 춘계학술대회논문집
1. Introduction
The SimMechanics is a very strong simulation software in the mechatronics field. It can be used to analyze dynamic and control designs in the complicated structures as much as 5-axis machine tools, robot hands and so on [2]. But the disadvantage of this method is for each mechanical structure must be created a model. There are many different configurations of machine tools [1]. Hence, it takes so much of times to create the models in SimMechanics. To save the time in design process, this paper proposed a new method to analyze multi-axis machine tools using SimMechanics.
The machine tools always use two motions, that are translation (T) along axis X,Y,Z and rotation (R) around axis X,Y,Z on a rectangular Cartesian coordinate system. The method is used this paper to simulate multi-axis machine tools is created a library include 62 SimMechanics models. The translation axis XYZ and the rotation axis ABC is not used in the library that it is replaced by Translatory and Rotary axes. The translation axis XYZ and the rotation axis ABC will be customized by transformation axes in the Cartesian coordinate system.
2. Using SimMechanics in controller system Fig1.a shows a part in the control model using Lagrangian equation, Fig.1b shows a part in the control model using SimMechanics.
Fig.1
The stiffness and damping parameters are installed in the Cartesian joint. There are eight Cartesian joints is used in this case, four in the vertical direction and 4 in the horizontal direction. They are linked with the stage by 8 spherical joints. When the external forces apply on the stage, the motion process of stage will be simulated. Hence, the complicated sate-pace equation can be replaced by the SimMechanics model in the control system.
3. Development of multi-axis machine tool models.
No. Axis Number of configuration Traditional Method New Method
1-Axis 6 2(21) 2-Axis 30 4(22) 3-Axis 120 8(23) 4-Axis 360 16(24) 5-Axis 720 32(25) Total 1236 62 Table 1.
SimMechanics 를 활용한 다축 기계장비의 모델링 기법
Development of Multi-axis Machine Tool Models Using
SimMechanics
팜반딘1,2, #송창규1,2 , 김병섭2
P.V. Dinh1,2([email protected]), #C. K. Song([email protected])1,2, B. S. Kim2 ([email protected])
1과학기술연합대학원 나노메카트로닉스학과
, 2한국기계연구원 초정밀 시스템 연구실 Key words : Multi-axis; machine tool; control system
a, b, x' = Ax+Bu y = Cx+Du State-Space K*u Motor xyz-dir K*u Encoder xyz-dir
537
한국정밀공학회 2013 년도 춘계학술대회논문집
To simulate the controller systems using SimMechanics, we have to build the SimMechanics models like Fig.2a and Fig.3a and combination with Simulink. Hence, to simulate the multi-axis of machine tools case, we must be created 1236 SimMechanics models in the traditional method. To reduce the number of configuration, this paper used the translation axis and rotation axis method.
Fig.2a shows the SimMechanics model in the 1-axis translation case. But it can be transformed into Fig.2b, Fig.2c by the replacement axis method. So the number of SimMechanics model need to be created are one Translation and one Rotation axis (T & R).
In the two-axis case, the number of SimMechanics models must be created are 22 = 4 (TT, TR, RT, RR). Hence, the equation to calculate the number of SimMechanics model as following.
N = 2t Where:
t: number axis of machine tool. N : Number of SimMechanics model.
Fig.3 shows the SimMechanics model in 2-axis case (TR). But it can be transformed into 30 other configurations (Fig.3b, Fig3c, Fig.3d etc.) by the replacement axis method.
Fig.4 shows the main program to choose the configuration of machine tools. Firstly, choice number axis of machine tool and then choice workpeace carrying axes, the next step is choice tool carrying axes, click Confirm bottom. The program
will process and export the result.
4. Conclusion
This method was developed to help the controller simulation software of multi-axis machine tools.
It can be solved the complicated configurations of machine tools and suggestion for designers chose the optimal options in design process.
Saving times build the data bases for simulation software.
References
1. E.L.J Bohez “Five-axis milling machine tool kinematic chain design and analysis” Machine tool & Manufacture 42, 505-520, 2002.
2. L. Brezina, O. Andrs, T. Brezina “NI LabView – Matlab SimMechanics Stewart platform design” Applied and Computational Mechanics 2, 235-242, 2008.
3. SimMechanics Getting Started Guide R2012a
