COTS Elevator in Action

[Mr V]

Originally Posted by lynca

The pulley and spool were separate parts from different companies.
I would not recommend pulley-spool approach because the cable will slip or come off the spool.

If you have the time, use a chain or timing belt system to avoid slipping on your elevator.

As for the linear slide itself, there are lots of options that are COTS but most are quite expensive.
We also prototyped with Rev Robotics Rail system and that will offers even more customization for elevator tower geometry than the robot compeition parts system.

While I wouldn't recommend a cable for use in a string and pulley set up I would highly recommend a paracord and pulley set up.

If your "string" can come off of the pulley then you haven't selected the right pulley/string combo or haven't put a shield on it to prevent the string from coming out of the pulley. It is all in the proper selection and/or design of the pulley to "string" interface.

Power down is also easy to do with the string and pulley set up. I recommend a divided drum and a captive spring tensioner to account for the possibility or variability in wrapping on the drum.

I don't understand why you would think that it would slip on the drum. The "string" should be anchored to the drum so no possibility of it slipping. You should not just wrap the string around the drum and tie it.

Millions of cars on the road today use a string and pulley set up for their window regulator and they last for many years. This method has been used for over 25 years.

Having used a chain driven lift on a number of competition robots over the years and using paracord and pulleys for the Team [REDACTED] Ri3D machine I would never choose a chain driven set up again. It is heavy, a pain to attach to and a pain to properly tension and problematic to repair quickly.