Lego Generator





Introduction: Lego Generator


I was screwing around with some of the motors from my old Lego Mindstorms kit, and discovered that when two motors were directly connected to one another the spinning of one would cause the other to spin too. It was obvious once I realized what was going on, but still strange to see the other motor spinning without being connected to anything but the other motor.

Step 1: Parts

The only things really needed to do this experiment are the motor and the power wire connector. To demonstrate on a second motor you need a second motor, to measure the voltage you need a multimeter, to demonstrate on an LED you need an LED, etc. A rubber wheel is also a good idea because it will be easier to grip then the axle coming from the motor.

Step 2: Procedure

Connect the power wire to the motor, put the wheel on the motor.

If you are demonstrating on another motor:
-connect the power wire to another motor with a wheel on it.
-spin one of the wheels and notice how the other wheel will spin
-to get the wheel to spin in the other direction reverse the polarity of the wire connections by unplugging the square connector and plugging it back in facing the other direction

If you are demonstrating on a potentiometer:
-connect the square power piece on the end of the wire to the 2 leads from the potentiometer
-set it to 20v dc and spin the wheel as hard as you can, from just running it on the desk the highest I generated was 19v
-optional: connect the motor to a dremel or a power drill and see how much voltage you can get it to generate

If you are demonstrating with a LED:
-connect the square power piece to the LED (I used the same LEDs that were used for the throwies)
-spin the wheel, the LED should light up, if not check polarity

Step 3: Potential

This experiment has huge potential for many different projects. It can be attached to almost anything with motion, in order to generate electricity.

The perfect project for this would be a bike light. Unfortunately, since I am away from most of my parts and tools, I do not really have the opportunity to test it it out. Hopefully someone reading this will further experiment with it seeing what interesting things they can make.

Multiple motors can be used, to create either more amperage or more voltage, depending on how they are connected.



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    you should put one of those motors at each wheel it will make it 4 wheel drive. and what motors are using

    I'm 38 yrs old and have never had a car drivers' license. Excuse me if I'm off here - and please correct me. It has always puzzled me why there are no magnet generators installed on every wheel that spins on every vehicle that travels - cars - bikes - trikes - shopping carts?. Now I know I'm getting a bit hyperbolic but - really - why is this energy wasted. Another thing I will just throw out there is if we could use capillary action (or some other currently overlooked action) to raise water above sea level we could harness the power of it's descent through big pipes (think flushing the toilet) to drive turbines. Nice post sir.

    they dont use them in shopping trolleys because people can jack/steal them.

    ever ride  a bike with the dynamo (for the lights) on?
    ul notice that ul have to kick harder, so, more energy used, for less energy output.
    on a car, this already is being used for things as the battery (for starting the engine, lights, dashboard, etc) but the energy that is needed (gas/diesel) to generate other kinds of energy (elektricity) is equal, but mostly a bit less since theres a small resistance from the wiring.
    so, it would actually wasting energy...
    i already thought of  that, and its a nice experiment :)

    btw, if ul make this experiment (with that lego thingies) large enough, ul notice that the second engine is *slightly* spinning slower...

    its like one of those free energy machines, they don't work =)

    because driving the magnets would effectively slow down what ever u are moving and more energy would be needed to move it. thus being completely pointless

    That's how all hybrid cars work now, I beliebe - when they're free-rolling the momentum charges the batteries.

    only when brakes are applied plus it is not set up to collect on every wheel if there where 'good' enough batteries and enough of them it would be beneficial to collect power from every wheel btw: alternator is only from the engine spinning (as for you hoihoi151 I am 14 years old)

    they use the turning of the wheels to generate electricity only when the brake pedal is applied. that is why they don't do much better than normal cars on the freeway; you dont break much

    there is a big generator attached to the wheels through the axils and gears called an Alternator