take your mains power and convert it into whatever voltage you want.

But there is even a "small" loss there too. Even a transformer isn't 100 percent efficient.

 

May be, start with half the system.
look at the pendulum part of the circuit.

If you wanted to measure the displacement, you could do worse than a LVDT
https://en.wikipedia.org/wiki/Linear_variable_differential_transformer

A simpler version of that, just a coil and a permanent magnet, would generate AC as the magnet moved back and forward.
This sounds possible, not least, looking forward, its lite, and the wires going to it can be small, and hence wont upset the beam when its mounted on that.

The beam, a variation on the LVDT is the rotary encode, which if you have a permanent magnet , is a dc motor,
as the beam rotates it clock wise then anti clockwise, then again you will get a AC waveform out.

It would be intellectual interesting, just showing how little energy can be harvested like this.

But as the others have said, if your looking at getting more energy out than you put in, a) thats against current laws of nature, b) against the rules of this forum,

 

I've torn apart a lot of old cassette tape players. Those pickup heads are very sensitive to electromagnetic changes. Those changes - which represent audio recordings - are then amplified through a series of amplifiers. Typically a "Pre-Amp" then an Amplifier. If you're looking to see how much energy can be harvested - that's a starting place. But your amplifiers will use far more energy than you can harvest from the pickup head.

 

May be, start with half the system.
look at the pendulum part of the circuit.

If you wanted to measure the displacement, you could do worse than a LVDT
https://en.wikipedia.org/wiki/Linear_variable_differential_transformer

A simpler version of that, just a coil and a permanent magnet, would generate AC as the magnet moved back and forward.
This sounds possible, not least, looking forward, its lite, and the wires going to it can be small, and hence wont upset the beam when its mounted on that.

The beam, a variation on the LVDT is the rotary encode, which if you have a permanent magnet , is a dc motor,
as the beam rotates it clock wise then anti clockwise, then again you will get a AC waveform out.

It would be intellectual interesting, just showing how little energy can be harvested like this.

But as the others have said, if your looking at getting more energy out than you put in, a) thats against current laws of nature, b) against the rules of this forum,

As a retired physicist I’m not looking to break any of the laws of Physics but to explore some electro-mechanical techniques.
Perhaps if I’d shown the motor at the top of the pendulum in my original drawing I wouldn’t have raised the forum’s temperature.

Pic attached

 

As a retired physicist I’m not looking to break any of the laws of Physics but to explore some electro-mechanical techniques.
Perhaps if I’d shown the motor at the top of the pendulum in my original drawing I wouldn’t have raised the forum’s temperature.

Pic attached

My apologies,

I thought i was giving you some good ideas as to possible ways of getting a reading on the energy in the system, and highlighting to you why the rues of the forum might be causing a few problems to you,

Please, no offence was intended,

We were inundated a while back with schemes to make free energy,

keep us in the loop as to how you get on, and a suggestion, highlight in double intensity words that you know you get less energy out than you put in,

 

My apologies,

I thought i was giving you some good ideas as to possible ways of getting a reading on the energy in the system, and highlighting to you why the rues of the forum might be causing a few problems to you,

Please, no offence was intended,

We were inundated a while back with schemes to make free energy,

keep us in the loop as to how you get on, and a suggestion, highlight in double intensity words that you know you get less energy out than you put in,

Yes there have been some good ideas here and I will look into one or more. Let me say here and now that NO SYSTEM IS MORE THAN 100% EFFICIENT. Heat losses for one and entropy make sure of that. However, many energy systems are open, like solar panels and heat pumps, so energy from the environment, from the sun at the end of the day, can be brought into the system. But that’s another issue and not in contravention of the laws of Physics as I taught my secondary science students when I turned to teaching.

 

Yes there have been some good ideas here and I will look into one or more. Let me say here and now that NO SYSTEM IS MORE THAN 100% EFFICIENT. Heat losses for one and entropy make sure of that. However, many energy systems are open, like solar panels and heat pumps, so energy from the environment, from the sun at the end of the day, can be brought into the system. But that’s another issue and not in contravention of the laws of Physics as I taught my secondary science students when I turned to teaching.

I agree with you about efficiency, its total energy in against total energy out.

 

I agree with you about efficiency, its total energy in against total energy out.

Yes and we must differentiate between efficiency and ‘coefficient of performance’ which is energy out / energy provided by the operator. A ground source heat pump typically has an efficiency of 70% but a CoP of 3.

 

It’s examining efficient ways to extract energy from an oscillating beam.

To what end?

Look at an oil/water pumpjack and you can see how to use an oscillating beam to transfer energy from a prime mover to a load. The efficiency is dominated by the efficiency of coupling energy into the beam from the prime mover and the efficiency of coupling energy from the beam to the load. The efficiency of the beam itself as a transfer mechanism between the two is nearly 100% with small frictional and flex losses.

But it doesn't sound like that is what you are looking at. What are you looking at? What is the end goal? What are you looking to accomplish when all is said and done?

 

To what end?

Look at an oil/water pumpjack and you can see how to use an oscillating beam to transfer energy from a prime mover to a load. The efficiency is dominated by the efficiency of coupling energy into the beam from the prime mover and the efficiency of coupling energy from the beam to the load. The efficiency of the beam itself as a transfer mechanism between the two is nearly 100% with small frictional and flex losses.

But it doesn't sound like that is what you are looking at. What are you looking at? What is the end goal? What are you looking to accomplish when all is said and done?

I’m looking at efficient and novel ways to transfer mechanical energy to electrical energy. My mecanno build was a simple way to explore the idea. Amazing what COVID shielding makes one think of doing!

 

The the ‘pumpjack’ idea does sound interesting too. Any useful sources about it?

 

I want to learn some more classical mechanics and learn to study/build machines that way. That be the perfect way to analyze your machine's motion and KE/PE

 

I want to learn some more classical mechanics and learn to study/build machines that way. That be the perfect way to analyze your machine's motion and KE/PE

Take a crack at writing the Lagrangian.

 

I followed the work of Veljko Milkovic. He pursued developing a way to improve pumping water by hand.
The Milkovic 2 stage pendulum also transfers additional energy thru an impact vibration. The metal and dimensions
are carefully chosen to take advantage of this.

I believe that the conversion to a spinning flywheel at high RPM lends itself to measuring this type of oscillating.
Probably to absorb enough impulse the model should be larger.

 

I followed the work of Veljko Milkovic

I had not heard of him, but then Googled the name. While the Youtube videos show a amplification of power (for a very short amount of time) there was no real work being done. And the pendulum need input to even keep it working. I can see no real advantage to doing what he was doing. Can you give a better link to show something that gets a mechanical advantage from his experiments?

 

This is my circuit for pulsing the motor at the top of the pendulum. I’ve built it but can’t get a square wave and haven’t yet found the fault. I get a lot of high frequency signals and noise.

Can someone just check over my attached circuit? I’m in fact using an electrolytic capacitor at C and IN4007s instead of the IN4148s.

Thanks

 

This is an interesting query and certainly has attracted a lot of attention, and a lot of comments from the clueless. Only a method that does not involve any contact would be very efficient, and so you are limited to magnetic coupling. That would be having that moving mass on the end of the beam be a rather strong magnet and having it moving through a rather closely fitting solenoid coil. A voltage will be developed across the coil, and power can be extracted with the current into a load. But it will not be a lot because of the slow speed. You can calculate the energy and compare that with what you get to evaluate the efficiency.
I am suspecting that this is an experiment intended to evaluate methods of capturing energy from some natural motion source, and probably you do not wish to share that part of the concept. Good Luck.

 

This is an interesting query and certainly has attracted a lot of attention, and a lot of comments from the clueless. Only a method that does not involve any contact would be very efficient, and so you are limited to magnetic coupling. That would be having that moving mass on the end of the beam be a rather strong magnet and having it moving through a rather closely fitting solenoid coil. A voltage will be developed across the coil, and power can be extracted with the current into a load. But it will not be a lot because of the slow speed. You can calculate the energy and compare that with what you get to evaluate the efficiency.
I am suspecting that this is an experiment intended to evaluate methods of capturing energy from some natural motion source, and probably you do not wish to share that part of the concept. Good Luck.

I’m happy to share what I’m doing which is observing the way energy is transferred from a swinging pendulum to a horizontal beam and, in the process, querying the optimum way one can extract energy from the oscillating counterweight.

’ve mentioned before the idea of suspending a Neo magnet on a thread and letting it move within an air coil made of fine (27swg?) wire. I have already calculated the GPE energy available from the counterweight and that comes to 184mW so it will be interesting how much of that I can extract.

Any thoughts on my timer circuit? Looks right to me but I’m not experienced in that line.

Jules

 

Any thoughts on my timer circuit? Looks right to me but I’m not experienced in that line.

There are several problems with that circuit.

First, you absolutely MUST use a decoupling capacitor or capacitors across the 555's power pins, 1 and 8. I would suggest a 100 nF ceramic capacitor in parallel with a 1-10 μF electrolytic or tantalum capacitor, located as close as possible to the IC pins. Decoupling caps are necessary for two reasons: one, the 555 is notorious for producing a prodigious amount of "shoot-through" current each time its output changes state (for a few nanoseconds during the transition, both the upper and lower output transistors can be conducting). And two, to keep the 555's timing from being affected by electrical noise appearing on its power connections. And motors can produce a LOT of noise.

Second, your pot Ra should have a fixed resistor (perhaps 1 kΩ or so) in series with it so that when the pot's wiper is in the leftmost position it does not short the 555's pin 7 to pin 8. Were that to happen, you could easily overheat (and possibly destroy) the 555.

Third, you should check your power topology. Especially when dealing with motors and other heavy switched loads, properly segregating current paths is important to keep circuits from doing "funny" things. Current flowing though the motor should NOT be allowed to flow through any of the wires making up the 555's circuit. Remember, every wire is both a resistor and an inductor, and currents flowing through a wire will have a resultant voltage drop along that wire; and sudden changes in current (such as when switching a motor on and off) will cause a transient voltage spike along the wire. If these voltage drops/spikes occur within the 555's timing circuit, they can disrupt operation. To prevent this, connect the top end of the motor and the cathode of its catch diode DIRECTLY back to the +12V power input terminal without going through any of the 555's connections, and in like manner connect the emitter of your BC548 directly back to the 0V power input terminal.

 

There are several problems with that circuit.

First, you absolutely MUST use a decoupling capacitor or capacitors across the 555's power pins, 1 and 8. I would suggest a 100 nF ceramic capacitor in parallel with a 1-10 μF electrolytic or tantalum capacitor, located as close as possible to the IC pins. Decoupling caps are necessary for two reasons: one, the 555 is notorious for producing a prodigious amount of "shoot-through" current each time its output changes state (for a few nanoseconds during the transition, both the upper and lower output transistors can be conducting). And two, to keep the 555's timing from being affected by electrical noise appearing on its power connections. And motors can produce a LOT of noise.

Second, your pot Ra should have a fixed resistor (perhaps 1 kΩ or so) in series with it so that when the pot's wiper is in the leftmost position it does not short the 555's pin 7 to pin 8. Were that to happen, you could easily overheat (and possibly destroy) the 555.

Third, you should check your power topology. Especially when dealing with motors and other heavy switched loads, properly segregating current paths is important to keep circuits from doing "funny" things. Current flowing though the motor should NOT be allowed to flow through any of the wires making up the 555's circuit. Remember, every wire is both a resistor and an inductor, and currents flowing through a wire will have a resultant voltage drop along that wire; and sudden changes in current (such as when switching a motor on and off) will cause a transient voltage spike along the wire. If these voltage drops/spikes occur within the 555's timing circuit, they can disrupt operation. To prevent this, connect the top end of the motor and the cathode of its catch diode DIRECTLY back to the +12V power input terminal without going through any of the 555's connections, and in like manner connect the emitter of your BC548 directly back to the 0V power input terminal.

Thank you for the detailed response. I will deal with each of those areas and feedback in due course.