I have a sensor that is about 120 grams that I would like to be able to lower and pull up with some sort of pulley system and string. What would be the best type of motor for this? I have been looking into stepper motors but they seem to be fairly expensive and have a larger footprint. Would servos be able to send back position feedback so I control how many times the pulley turns?
Thanks for the advice.
Would servos be able to send back position feedback so I control how many times the pulley turns?
Hobby servos generally don't send any type of feedback.
1 meter would be ideal
Have a look at sail winch servos. They do about 2.5 turns and you could probably fit a larger pulley to them to get the movement you need as your load is small.
While hobby servos don't have feedback they don't really need it as they are designed to move to a commanded position (assuming the load on them is within their capability).
...R
Maybe a look here as well. The geared motor should support the load okay and maybe not slip if motor power is removed. You would maybe need an H-Bridge board to easily reverse direction of motor. The encoder should allow accurate control of rotation.
lpbug:
I have been looking into stepper motors but they seem to be fairly expensive and have a larger footprint.
Well, expensive, I think not. I was actually just musing on this today. At least two in every printer you find deposited as "road-kill" on the kerb. There might even be a control IC in there somewhere, though rather more difficult to locate as such.
As well as of course, eBay.
Right- but the steppers in printers are a quite a bit too big for my application. I am trying to go as small as I can for the load, which is not very heavy.
Thanks