I have been researching how to transfer electrical power from stationary to rotational part. Some of them showed the means by using slip spring rings like in this website
http://www.luberth.com/analog.htm (under the An Analog & Digital propeller clock section)
But it does not specify how do you actually assemble that?
So how do you connect the slip spring rings in your setup? Do you connect it to the motor's shaft? But only the ground terminal can be retrieved from the motor's rotating shaft? Where can we get the V+? It was not specified in the website. What are other components that are mainly used for this application.