In the 60’s and 70’s, my dad worked off and on on building one of these things in the garage; he called it the “Friction Compensator”. (eROCKIT electro-assist bicycle)
I’m not kidding. He was an electrical engineer by education, and also converted a 1947 Crossley to electric power with a big rack of lead-acid batteries in the back. Drove me to kindergarten in it a few times.