Low-Power Motor Can Run for Years on a Coin Cell

Can you run an electric motor for two years on a single lithium coin cell? [IamWe] figured out how to do it, and even though his donut motor doesn’t look like any motor we’ve ever seen before, it’s a pretty solid lesson in low-current design.

The donut motor is really just a brushless DC motor with a sign-pole stator and a multi-pole rotor. The frame of the motor is built from a styrofoam donut, hence the motor’s name. The rotor is a styrofoam sphere with neodymium magnets embedded around its equator. A sharpened bicycle spoke serves as an axle, and …read more http://pje.fyi/Q7XyRv

Paul Jacob Evans

Advertisements

Smooth and Steady Cuts with an Improvised Power Feeder

Some woodworking operations require stock to be fed at a smooth, steady rate, for which purpose a power feeder is usually employed. They’re expensive bits of gear, though, and their cost can usually be borne only by high-output production shops. But when you need one, you need one, and hacking a power feeder from a drill and a skate wheel is a viable option.

It should come as no surprise that this woodshop hack comes to us from [Matthias Wandel], who never seems to let a woodworking challenge pass him by. His first two versions of expedient power feeders were …read more http://pje.fyi/PqkCc1

Paul Jacob Evans

Hackaday Prize Entry: Very, Very Powerful Servos

A few years ago, [patchartrand] decided to build a robot arm. The specs were simple: he needed a drive system that would be at least as strong as a human arm. After looking at motors, [patch] couldn’t find a solution for under $3,000. This led to the creation of the Ultra Servo, an embiggened version of the standard hobby servo that provides more than ten thousand oz-in of torque.

Your typical hobby servo has three main components. The electronics board reads some sort of signal to control a motor. This motor is strapped into a gear train of some sort, …read more http://pje.fyi/PNS945

Paul Jacob Evans