As the known tinkerer of this site, I am always looking for cool cheap alternatives to solve a problem. In my undergraduate career, I was involved in a UAV design project and one of my specific tasks was to design the gimbal mechanism. In a traditional UAV gimbal, there are usually two or more servomotors adjusting the angle of the camera as the algorithm tracks its target. One major concern with this concept is, when the motors are continuously moving, will the the wires become tangled? In the case of rotary motion, a possible solution would be to use a slip ring. A slip ring is a rotary connector that allows two components to be electrically connected and spin freely.
The issue with this, however, for the designer on a budget is, if there are multiple moving parts and each slip ring costs between 20 and 30 dollars, you are quickly using up your budget. In my travels, I came across a “tangle-less” telephone connector for land line phones that only costs about 5 dollars (depending where you look).
This connector has four pins and can rotate continuously. At first I was a bit skeptical about the connection strength but, after checking the resistance across each pin, I found it was close to zero, and I was ecstatic!
I was able to get my hands on a much cooler black one
For the first step, I needed to gain access to the pins, so I cut away the plastic on the top and bottom using a standard Dremmel.
After removing much of the plastic, you will notice that the connections have become loose and may fall out. To fix this issue, carefully hot glue them into the optimal position (making sure they are all connected).
Added Hot Glue
Like most tinkerers out there, when you finish a project, you realize there are more ways you can improve it. So, I cut away the entire top half to make access to the wires even easier (using the Dremmel again.)
As you can see in the video below this 4-pin slip ring spins perfectly. (Say hello to Charlie!!)
Moving forward, you can use jumper cables on the top and heat-shrink wires to the bottom connections. Please leave any questions or comments in the section below! I’m always up for listening to new improvements for these designs, or hear how you’ve used them yourself!