I have simulated an industrial sewing machine. I want the input crank to rotate with constant 1450 rpm and I have been trying to figure out the torque which needs to be given to the input joint for this motion.
For this purpose I defined a motion to input joint. And I defined a joint sensor which gives the computed torque. I need the RMS value of the torque plot. But I am not sure that I obtain the correct curve for computed torque.
Because I expect that when I increase the inertia of the input link, the fluctuation of the computed torque curve decreases. But it is not. It is always the same curve below.
I even tried to increase the inertia to 999999999kg m^2 and nothing has changed. I also expected to have higher initial torque but I did not have either. I am attaching the file. I have to have the curve of this torque at steady state to compute the RMS value for selecting suitable motor. My system is as follows:
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Also in my opinion the curve needs to repeat itself in every 60/1450=0.04 sec. Because each cycle needs to be same. But this curve repeats itself about 0.08 sec.I dont know the reason. I would be glad if you help me. Also I would like to learn how can I compute the RMS value by using MATLAB.
Thank you
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