Can a robot actuator also transmit 20v as a slip ring?

I’ve got this amazing actuator designed by LoboCNC that does a 38:1 reduction from a 35mm stepper which will be quite effective in a robot arm, but I’m wondering if I can also extend it to be a slip-ring at the same time to carry the 20v across the whole robot? The rest of the signals for coordination should go across Bluetooth, so this will be a robot with 0 wires possibly.

Here’s the 2mm wide copper tape I’m trying to use and the PLA brushes hanging off the top side of the actuator that will touch the other side of the ring. I think this just might work, but worried about the copper wearing out if I’m just using tape. However, this is just a hobby robot, so probably would wear out long after its usefulness.


You might consider phosphor bronze for both sides. It is what is typically used (though often nickel plated for corrosion resistance) for battery terminals.

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Here’s an example of what’s available:

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Thank you for that suggestion. I had no idea phosphor bronze was typically used. That sheet looks cheap and easy to use instead of copper tape, albeit this adhesive on the copper tape is quite convenient.

I got the top lid wired with a standard header connector. Soldering to copper tape against PLA ain’t easy. Need to now get the wired connectors in the base, but I’ve got great conductivity as seen in the video, minus one spot that seems dead. I’ll have to add a redundant arm at 180 degrees to have two brushes per conductor.


Got the bottom part wired/soldered up.

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You might consider putting 3M VHB adhesive on one side of phosphor bronze sheet before cutting it into strips, giving yourself essentially the same idea as the copper tape, but with phosphor bronze.

20V is fairly high for DC; above 24V switches typically use special coatings to avoid damage from arcs, and if you have incomplete connections you’ll end up with arcing. Phosphor bronze is harder, and should resist arcing damage better. It’s also springy, so you won’t have to back it with PLA springs, so you won’t have to try soldering against PLA which sounds to me like a pretty frustrating enterprise.

Good luck!

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