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Synchronizing 2 Servo Motors Connected to 2 Rolls with Different Diameters
How can I synchronize 2 servo motor connected to 2 rolls of different diameters for positioning application? Due to different roll diameters, I am facing overload issues in motors.


Application: Positioning

I have 2 roll with different diameter connected with servo motor.
Application is to do positioning. 2 Roll are connected with each other by conveyor belt (no scope of stretching) and need to do positioning (highly accurate).

I did positioning with roll diameter of master (luckily master & slave dia were same [differant was 0.5mm]). So 1 machine done, but when I try to do with 3 ~ 4mm diameter difference then I face overload in either drive 1 or drive 2.

So How can I synchronize 2 servo motor connected to 2 different diameter of roll in positioning application? Can anyone suggest me how to control it?

Thanks in advance

It seems that you must change Gear Ratio from step to step according to difference in motors' load.

>It seems that you must change Gear Ratio from step to step
>according to difference in motors' load.

Initially in first installation roll diameter were near to same so I use same gear ratio to calculate roll circum in servo motor. But now roll diameter are different. Can you help me out? if anyone can provide me mail id then I shall mail you my sketch for better understanding.

I have seen some machines are working but those people are not sharing their control method.

1 out of 1 members thought this post was helpful...

Do you use standard Master-Slave configuration - i.e. Slave controlled by Master encoder?

Do you have high or low difference between both rolls' diameters?
What's happens if you keep Gear ratio constant? i.e. one of motor load is increased?

Thanks for the reply,

I use 2 different roll diameter instead of master slave configuration and that is the problem. As both the servo motor are connected with each other by conveyor on different diameter meter of rolls (differance come up to 10 to 15mm)

Can you help me to guide how to do master slave configuration? I will synchronize only master (I will find its roll circum by setting up 1000mm position) and slave will follow master.

Or can I have your mail id so I can mail you the drawing so you can guide me better.

By Bob Peterson on 28 December, 2017 - 3:25 pm

This seems like a run of the mill electronic gear ratio application. Most motion control systems have this capability.