This May be the World’s Easiest Motor, Constructed with Some LEGO Components

Jamie from Jamie’s Brick Jams selected to get again to fundamentals, thus no fancy motors for him. He’d beforehand made some subtle motors, however for this one, he wished to return to simplicity. That’s precisely what he obtained: easy, straightforward mechanicals constructed with fundamental electromagnetic ideas and some non-LEGO elements. Virtually the entire items could be assembled utilizing common LEGO items.

It’s powered by a rotor consisting of two neodymium magnets connected reverse one another throughout an axis. These magnets are balanced such that the rotor spins easily with out wobbling excessively. Subsequent to it’s a coil of wire that Jamie hand-wound round a LEGO form. That is the driving coil, and when a present flows by way of it, it generates a magnetic subject that interacts with the rotor magnets, giving the meeting a slight nudge.

The meeting begins with a single pulse from a 9-volt battery, however momentum alone lasts just a few seconds. To maintain issues transferring, Jamie added a second coil that features as a sensor. When a magnet passes by, it creates just a little present within the sensor coil. That present is then despatched to a easy circuit that features one TIP31C transistor and an elective LED. The transistor solely activates for a second, sending a short burst of energy to the motive force coil. Every burst is solely one other nudge to maintain the rotor spinning. Each pulse causes the LED to blink, indicating that the timing is right.

After all, polarity is essential; if the factor is failing to spin easily, swapping the connections on one of many coils is usually all that’s required. The transistor is admittedly carrying extra present than it ought to, but stays reliable and features correctly. The digital facet of issues is pretty easy, with one transistor, an LED for suggestions, two coils, and a battery.

Jamie wound the motor coil to round 150 turns of 27 gauge wire, and the sensor coil to about 100 turns of finer 32 gauge wire. LEGO bricks, such because the rotor cage and coil mounts, make up the body that retains every little thing collectively. To maintain the magnets regular throughout testing, a small quantity of short-term glue is utilized to the rotor. Within the demo, the easy two magnet model chugs alongside at round 1,300 RPM earlier than gearing. Including a 3:1 gear discount slows issues down however will increase torque considerably, and with some further LEGO gearwork, belt drive, and an outdated steering system from a 90’s set, you may even get a small LEGO automotive to maneuver throughout a floor.

Jamie later experimented with a rotor with eight magnets in a disc. They used the identical coils, however this time the pace was slower, round 480 RPM, however the torque was a lot increased, and the functioning was smoother as a result of the pulses had been coming quicker. The 8 magnet configuration permits the little car to journey with a lot higher confidence.
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