Cable drive system?

Help & Support Robot Parts
1

I am building a servo controlled Pinocchio nose system where the nose needs to grow around 250% longer than its original size. A standard actuator would not get the job done. I have searched for a cable drive system similar to a motorized plumbers snake that would push a spooled cable to extend the nose.

How could this be accomplished?

Here is a video of what I am trying to build: youtube.com/watch?v=g0h3rAQRsnY

I believe that something like a bicycle brake cable is being used and hidden in the straps that hold the nose to the face.

2

There are many ways to create a telescoping system.
If the nose is lightweight, can you hack a retractable measuring tape (remove the plastic housing and spring) so it operates using a continuous rotation servo or 785HB winch motor?

3

Thank you CBenson for the reply.

That is a great approach but too bulky to fit inside the nose. I am planning on using a Bicycle or bowden cable push/pull the nose so that I can put the servo, controller, and battery in a pack so that the servo doesn’t have to fit inside the nose.

Is there a pinch roller mechanism that I could connect to the winch servo that could move the inner wire on the bowden cable? Maybe something like a pinch roller and capstan like you would find on a cassette recorder?

4

Note that removing the plastic case around the tape measure would make it quite small (you don’t need to use a large industrial one either… there are keychain models well.
Unfortunately we don’t offer pinch roller mechanisms. The cable is an interesting approach, but it would need to be solid enough to push without flexing.