Investigation of dynamics of the winding process

The research of dynamics of coiling of the tight band has been done by using the mathematical modeling within MATLAB/SIMULINK. The step response of tension force on the band by using friction clutch has been investigated. The curves (Fig. 5) shows good control quality of the tension force to the reference signal of tension force witch appears ten second after the start. The system response to step of linear speed after 15 seconds is good enough but stabilization of the tension force appears with oscillations.

Similar experiments were performed with the real system, firstly giving step of linear speed and later step of tension force. For the measuring and registering the changes of linear speed and tension force the digital oscilloscope with two input channels were engaged. The scales of the signal measurement are: for measuring force 40 [N] per division and for measuring speed 0.2 [m/s] per division. During the first experiment values of the running coiling processes were as follows: tension force F=const=107.6 [N]; step of linear speed v from 0.3 to 0.6 [m/s] (Fig. 6a). The force F was slightly oscillated similarly to results of mathematical modeling (Fig. 5).

In the second round of experiments the values of the running coiling processes were as follows: step of tension force F from 53.8 to 107.6 [N]; keeping the linear speed v=const= 0.3 [m/s]. Good coincidence of experimental results with results obtained by mathematical modeling was observed (Fig. 6b).

Conclusions

1)    The lab stand with real tide band coiling system was designed and compared with mathematical model. The stand is designed in the way to control the rewinding process with direct measurement of tension force. With this stand there exist several possibilities to demonstrate and investigate various conditions of coiling process for educational and scientific purposes.

2)    The mathematical model has been developed to simulate the real stand for tide band coiling. Mathematical modeling allowed to investigate the dynamics of coiling system and to find the relationship between the tightness of the band, and the coiling speed.

3)    The results of the mathematical modeling well coincide with the real experimental results. Therefore this model might be used for determining optimal PID controller parameters of the real tide band coiling system.

Acknowledgment

Authors and Department of Control Technology at Kaunas University of Technology would like to thank Lithuanian JSC Lenze for the donated equipment.

References

1)    Thiffault C., Sicard P. and Bouscayrol A. Desensitization to voltage sags of a rewinder by using an active dancer roll for tension control // IEEE-IEMDC'05, San Antonio (USA). 2005. P. 466 473.

2)    Radons G. and Neugebauer R. (eds.). Nonlinear dynamics of production systems. Weinheim; Cambridge: Wiley- VCH, 2004.