Controlled lowering of platform - motor recommendations?

Projects General Guidance
1

Hi everyone :slight_smile:

I'm working on a project which involves controlling the lowering of a loaded platform. My current plan involves a motor turning a threaded rod passing through the platform, similar to a 3D printer.

A load on the platform is only applied when it is being lowered or held stationary. When the platform reaches the bottom of the rod, its load can be removed and I plan for the motor to be reversed to send the much lighter unloaded platform back to the top of the rod.

I'm hoping that using this configuration will limit the load on the motor to just friction between the rod and the platform, (other than the reset), as I am trying to deal with reasonably large masses on the platform, ~3-5kg.

Does anyone have any recommendations on which kind of motor could be most appropriate to this application, considering it may need to resist some torque to stop the platform dropping too quickly / stop it moving all together? If its at all possible, ideally it should be extremely quiet as well.

Thank you so much for any help whatsoever! Please let me know if I can explain anything better.

2

Almost all your questions depend on the reduction gearing presented by the threaded rod drive.
Speed, torque and other variables will contribute the selection of motor, or motor and (another) reduction gearbox.

At first glance, i’d be looking at simple DC motors, with limit switches.
Keep in mind (depending on gearing),that there will be some overrun when the motor is stopped at the limits of travel.

3-5 Kg plus the platform isn’t much if you have a 10:1 reduction, and i’d probably allow double that as a designed load.