alt Hacker NewsWhy can't we just dump massive currents into spring returning solenoids with ~5mm or ~1/4" range of motion, and amplify that motion through tendon systems for whole joint motion ranges?
Replies
cyberax • today at 8:47 AM
You can play around with a solenoid calculator like this one: https://www.getzenquery.com/tools/solenoid-force-calculator/
TLDR; is that you need high current, meaning a lot of ohmic heating. With non-negligible back-EMF resulting in even more losses. Rotating motors essentially "lengthen" the travel of the "plunger" compared to linear motors.
Heat goes up with the square of current, so putting 10x the current to get 10x the force means 100x the heat.
Still, I think this idea is under-explored. There are probably applications for robots that move really fast, but only for a second before having to cool down.