Orbital shaker - DC servo or stepper motor

[Lluis]

Hi,

I wish to build an orbital shaker (a bigger version of these examples:
https://learn.adafruit.com/crickit-lab-shaker

https://www.thingiverse.com/thing:2983846

As my aim is that it will work continuously for months around 100rpm what is preferred in aspects of heat and weight on top of it, DC servo or stepper motor? High torque? Any other parameters to consider?
Thanks

 

[berkeman]

Welcome back to PF. How did your Scotch Yoke Mechanism work out from back in July?

TL;DR Summary: How to change Scotch yoke mechanism parameters in order to calculate slider movement

I design out of curiosity this Scotch yoke mechanism (left image) based on a scheme (right image).

 

[Lluis]

It came out nice. Thanks

 

[jrmichler]

Servo and stepper motors are overkill for applications that run at a single speed. Look for a gearmotor (search the term). A gearmotor is a motor combined with a gear reducer. A quick search found this on Amazon: https://www.amazon.com/dp/B0721T1PXQ/?tag=pfamazon01-20

I have no idea if this one meets your needs, nor do I have any knowledge of its quality. It's just the first one that popped up on a search for gearmotor with 100 RPM output. Given the low price, you might consider just buying it (or a similar one), and find if it works.

 

[Baluncore]

As my aim is that it will work continuously for months around 100rpm what is preferred in aspects of heat and weight on top of it, DC servo or stepper motor? High torque? Any other parameters to consider?

Avoid brush motors if you want continuous operation. Find a BLDC servo motor that will do the work needed without generating too much heat.

Avoid stepper motors, unless you need precision positioning. Steppers are not the most efficient way of converting energy.

I would consider a common AC induction motor, driving an eccentric mass. If I needed speed variation, I would use a variable speed drive.

 

[berkeman]

It came out nice. Thanks

Glad to hear it. It's common courtesy to reply to threads that you start where you get good help. That did not happen in your previous thread; hopefully you are able to reply in this thread with your thoughts on the responses you've received.

 

[Rive]

If fixed RPM is OK then ... well, I would start with an old vinyl player

 

[berkeman]

If fixed RPM is OK then ... well, I would start with an old vinyl player

With a belt drive to change up to 100RPM?

 

[Lluis]

Thanks a lot for the infornation