strange phenomena with stepper motor 1

[hardcak]

Hi,

Attached are 2 files showing a powerful servo motor set to rotate the clamp (improvising for now) 90 deg. The 2 setups only difference in arrangement is by attaching the clamp using a 50mm bush. Does anybody know why this version struggling to hold the torque and complete the cycle?? Nothing is slipping. Completely baffled?!!

 

[Skogsgurra]

More or less expected with a resonant and badly damped load like that. Add some damping (paddle in water or similar) to see better performance.

Gunnar Englund

http://www.gke.org

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Half full - Half empty? I don't mind. It's what in it that counts.

 

[hardcak]

its not an elegant solution, but we need a boss for a cheap solution. the clamp is an improvisation for now.
Im curious why adding this the boss creates this constant issue...seems strange to me like to like

 

[hardcak]

attached are both setups. the original attachment only showed the one..

 

[hardcak]

cogging perhaps?

 

[cswilson]

Your title says "stepper motor" but your post says "servo motor". The audio sounds more like a stepper motor. Which is it?

I'm guessing stepper motor, and think Skogs is likely correct. You changed the sqrt(K/J) resonant frequency of the system to where its natural oscillations worked against the command sequence.

Curt Wilson
Omron Delta Tau

 

[hardcak]

yes its a stepper motor. My knowledge on motors is limited - clearly!

Great i have started researching about resonance in stepper motors - and ways to combat this..

Thanks all