enter image description hereI am new to StackExchange and trying my best to stay within the rules. I have invented an efficient mechanism -- a rotating mass magnetically attached inside a closed loop (GB 2517244). I am attempting to apply an EMF (electro-magneto force) system into the mechanism to make an 'at source' electricity generator. The mechanism is based on the Kinetic (Chinese) Wheel yoyo. I am using a 1.5kg flywheel assembly rolling 0.5 m down a 3 degree slope. The mechanism, using a battery, sensors and electromagnets to rock a counter-balanced beam (as the engine), is made to complete an 'orbit' at 1 metre per second @ approximately 1600RPM.

Leaving aside 'start up' considerations and given each GPE (gravitational potential energy) renewal costs two 0.33amps inputs from the electromagnets, can I achieve more electrical output from an EMF arrangement along the transits than is needed to rock the mechanism?

enter image description here

  • Where should the energy you gather come from? Do you attach your device on top of a boat, so that wave movement make the wheel move back and forth?
    – J. Chomel
    Commented Aug 8, 2017 at 7:47
  • The mechanism is, hence the flywheel assembly, are in a counterbalance beam (engine) rocked using electromagnets 0.33amps per GPE renewal inside a closed loop. Single rotational direction is maintained by magnetic attachment along the upper transit (see Kinetic wheel yoyo or 'SMOT over unity' on YouTube for basic principle) The question is will a suitable EMF arrangement produce more than 0.33amps per transit from the rotational motion accrued from the mechanism's conversion of GPE to rotational energy?
    – Andy
    Commented Aug 8, 2017 at 9:37
  • 2
    Andy, have you considered the back-EMF which any electrical load on the output will apply to the "generator?" This will counter-act the kinetic energy of the rolling mass. With such a low incline it will not take much electrical load to slow the mass. Based on the laws of thermodynamics, we know in fact that the energy the mass produces must be less than the energy required to tip the beam and re-start the rolling motion. In a vacuum, and using finely tuned components, you could likely make this mechanism power itself and run a while, but not forever, and not with a surplus of energy.
    – LShaver
    Commented Aug 9, 2017 at 15:12
  • 1
    One point is unclear -- you say you need 0.33 amps to tilt the beam and re-start the mass rolling. This is a measure of current. How much energy is used -- that is, 0.33 amps at what voltage, over what time period?
    – LShaver
    Commented Aug 9, 2017 at 15:15
  • 2
    I'm voting to close this question as off-topic because it is about perpetual motion machines.
    – LShaver
    Commented Mar 3, 2020 at 18:33

4 Answers 4


No, you cannot get more energy out than you put in.

No, you cannot invent a perpetual motion machine.

  • 3
    How do you interpret his design as a perpetual motion machine? Frankly, I don't understand his description at all, and only assuming that I don't know enough about engineering kept me from flagging it as 'unclear'.
    – user2451
    Commented Aug 7, 2017 at 13:58
  • 1
    @JanDoggen AFAICT, he's using electricity to rock the beam, then trying to harvest the resultant kinetic energy to generate electricity
    – 410 gone
    Commented Aug 8, 2017 at 8:00
  • Jan Doggen, it is possible to see the 'mechanical' principle on YouTube under 'SMOT over unity'. Leaving aside the over unity reference it shows a ball bearing magnetically attached inside a closed loop and perpetuated by the guy's finger movement (manual work). I've replaced the ball bearing with a flywheel assembly and the manual work with electromagnets and a pivot. It costs 0.33 amps per repositioning of the beam to accrue high speed rotational energy. This is what I am attempting to 'harvest'.
    – Andy
    Commented Aug 8, 2017 at 10:12
  • As stated in the new 'picture synopsis' please be specific to the aspects of the concept. I'm not interested in unrelated regurgitated knowledge which tries to justify someone's misunderstanding.
    – Andy
    Commented Aug 10, 2017 at 12:35

Sophisticated watches with no battery do exist, but they use the movement of the bearer against earth gravity as a source of energy.

Here is your misconception: kinetic energy comes from within your system! To move something, you need energy, and when you collect electricity from that movement, you collect LESS energy that what is needed to move it. My opinion is you mix potential energy and renewable energy in your system.

If you want to user earth gravity as a source for energy, it only works until you reach the center of the earth. Then if you want to harvest more, you have to bring the mass where it began. And you need more energy than you could possibly collect in the first place by going down the first time.

In other terms, your system is consuming latent energy, which makes it another failed attempt at Perpetual motion.

troll physic http://imgarcade.com/troll-physics-magnet-car.html

And if you allow me, it's not a new idea:

Perpetual Motion by Norman Rockwell.jpg
By Norman Rockwell - Downloaded 2009-06-29 from Popular Science magazine, Vol.97, No.4 (October 1920), Bonnier Corp. New York, ISSN 0161-7370, front cover on Google Books, Public Domain, Link

  • Gravity is a constant at 9.81N, the mechanism accumulates inertia. Rolling 1.5Kg down an incline (and the flywheel assembly is continually made to roll downhill by rocking the beam) The losses incurred in the 'beam engine' are the pivot and (at start up) 1.5Kg. This take 0.33amps.
    – Andy
    Commented Aug 8, 2017 at 10:02
  • 1
    @Andy, You are correct, except you cannot collect more energy than what was used to bring the wheel up. We are just trying to help you save time and think of something better. A system like yours might be able to harvest energy if it has energy input, e.g. from see waves.
    – J. Chomel
    Commented Aug 8, 2017 at 10:50
  • I don't believe you are fully conversant with the principle of the mechanism, so I've added a compilation of pictures to help you. Norman Rockwell's picture would be rather amusing if only I hadn't come across such mechanisms that adhere to the conservation of energy, when I was so young and ignorant.
    – Andy
    Commented Aug 8, 2017 at 15:41
  • @Andy, as long as the wheel is set to its original position with electricity generated from your system, it will require more electricity to get there than it can possibly generate when it goes down. Do we agree on this?
    – J. Chomel
    Commented Aug 8, 2017 at 17:55
  • No. Start up energy, as with most machines requires more input than say an internal combustion engine at cruising speed. The proposed machine at working speed, 1600RPM, uses (now less than) 0.66amps per second per orbit.
    – Andy
    Commented Aug 9, 2017 at 12:29

Your system involves a 1.5kg weight rolling down a 0.5m slope of 3 degrees. Therefore, each time you reverse the mechanism you are raising the weight by 0.026m (basic trigonomety - sin 3 * 0.5m). To raise a 1.5kg weight by 0.026m takes 0.38J of energy. If you're doing this 26.6 times per second (1600RPM) you'll need 10.13W - at 0.33A you system must therefore be running off 30V.

If you assume there are no other losses, the most energy you can get out is therefore 0.38J as the weight rolls back to the lower level - it has 0.38J more potential energy at the top than it does at the bottom. It is physically impossible to get more energy out than you put in.


No, you cannot due to the second law of thermodynamics.

The Second Law of Thermodynamics states that "in all energy exchanges, if no energy enters or leaves the system, the potential energy of the state will always be less than that of the initial state."


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