control of 2 motors

[silver7854]

I have a unique problem that i haven't ever come across before, maybe someone has thought of this allready:

I have 2 motors that are driving linear actuators. These linear actuators are positioned in such a way that they are back to back, one actuactor acting 180 degrees in the opposite direction of the other. Both motors are attached in the middle, so the linear actuators push out in either direction away from the motors.

So here is the problem: The motors that drive the actuators do not have the exact same impedance, so they run slightly differently. these actuators are placed perpendicular to the ground, and there is a load on them. When we try to extend both at the same rate, the bottom motor doesnt act at all, while the top one does. We would like to make sure that both actuators extend at the same rate no matter what the load on them. Does anyone know something that i could build/buy to accomplish this?

thanks very much!
-Aaron

 

[itsmoked]

Are you running them with one supply or do they have their own individual supplies?

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[silver7854]

sorry, forgot to say i was only using one power supply to do this.

 

[sreid]

You say the motors are not exactly the same. Is it possible that one motor is small enough that it can't lift the load at all? Both actuators should be seeing the same force.

 

[silver7854]

also i forgot to say i'm sending one overall signal to both actuators (a signal the tells the entire system to extend to an overall length).

 

[silver7854]

its interesting because if i flip the system around and run it that way i the motors behave in the same exact way, except opposite. Whichever motor i place on the bottom always doesn't move, and the top one always moves first.

 

[Skogsgurra]

It would help a lot to know what motor type you use. DC, AC, three phase?

Gunnar Englund

http://www.gke.org

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