Mister Bill said:

positive displacement pumps

This has spawned a memory.

Before I explain, let me focus on what I was imagining: You said your beam (from where you intend to extract energy) was moving 5mm. A half swing up of 2.5mm and down 2.5mm. When Bill mentioned positive displacement it got me thinking of my fish tank aquarium air pump. It consists of an iron core, a beam with a magnet on the end, and a bellows. At 50 or 60 Hz it vibrates a very short stroke. Yet the bellows pumps a lot of air. In part it does so because of the speed at which it oscillates. At the 2.5Hz your beam seems to be oscillating at - the aquarium pump wouldn't be of any use. But I wanted to mention it anyway. Perhaps it may spawn a new idea in your mind or in the minds of others.

 

Actually it's upwards 5mm from its balanced position and then back to that again so it's not oscillating around a central position. It does that twice every pendulum cycle, so about every 0.8s. Yes, perhaps the mechanism of an Aquarian pump can create some air pressure. Ideally, though I would like to generate the output in electrical energy so perhaps my only option is the Neo magnet in a solenoid wound on an acrylic tube. It will take some trial and error.

 

In practice I’m jumping the gun here since my timer circuit seems unable to allow independent control of frequency and duty cycle which I need. I followed the link of a contributor, which is the basis of the circuit I posted a little while back, but it doesn’t actually do as I need.

So I need to rebuild the timer and wanted to ask if there is a design that allows independent control using one 555 or instead should I feed the output of one 555 into the input of another 555, the first setting frequency and the second duty cycle?

Thanks

 

I don't know what range of frequency and duty-cycle control you have in mind, but here's my suggestion for 0%-100% duty cycle control at an independently settable frequency :-


The two unused inputs of the CD4049B IC should be grounded. You will need to buffer the output of the circuit if you want to drive more than a couple of mA into a load.
C1 can be increased to lower the frequency from that used here.

 

I don't know what range of frequency and duty-cycle control you have in mind, but here's my suggestion for 0%-100% duty cycle control at an independently settable frequency :-
View attachment 210151

The two unused inputs of the CD4049B IC should be grounded. You will need to buffer the output of the circuit if you want to drive more than a couple of mA into a load.
C1 can be increased to lower the frequency from that used here.

Sorry I should have been more specific. I need 5-50% duty cycle and 0.2-50Hz.

Is it feasible to do it with 555 timers as I already have those rather than buy in new components?

Are U1a, U1b etc pins on the one chip?

 

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!

Yes, <chuckle> I went into investigating the properties of UVc light for disabling/killing viruses and bacteria. Turned out very interesting as i found very low level (regular) UVc can kill viruses.

As to your project, as you extract energy the beam will become more damped which means more power to keep it rocking.
Also, you might look into Wave Energy Converters to find a way to harness the energy from the up and down movement of the far end of the beam.

 

As to your project, as you extract energy the beam will become more damped which means more power to keep it rocking.

As I've been telling him. Any extraction of energy from anything does that. A swinging pendulum moving perpendicular to a beam is going to be even more effected than a link from a prime mover. It doesn't matter if it is electromagnetic,like he wants, or even a motor moving a link perpendicular to the beam, it's not a workable device. That is why it has never been used in mechanics. Doing the force vectors would/should show that to a "physics" teacher as he claims to be. Even a dummy such as I know that.

 

Are U1a, U1b etc pins on the one chip?

They are individual inverters in the CD4049B IC, which is an inexpensive 6-inverter package. The pin numbering is found in the datasheet. The Vdd and Vss pins of the IC supply are not shown in the schematic.
Your timer looks doable with a couple of 555s though.

 

They are individual inverters in the CD4049B IC, which is an inexpensive 6-inverter package. The pin numbering is found in the datasheet. The Vdd and Vss pins of the IC supply are not shown in the schematic.
Your timer is certainly doable with a couple of 555s though.

Thanks. I was hoping it was as I have those already. I was asking if you could direct me to a suitable circuit using 2 555s? The one I built that was supposed to do the job doesn’t.

 

As I've been telling him. Any extraction of energy from anything does that. A swinging pendulum moving perpendicular to a beam is going to be even more effected than a link from a prime mover. It doesn't matter if it is electromagnetic,like he wants, or even a motor moving a link perpendicular to the beam, it's not a workable device. That is why it has never been used in mechanics. Doing the force vectors would/should show that to a "physics" teacher as he claims to be. Even a dummy such as I know that.

Hi,

It's not perpendicular all the time. In fact, it's only perpendicular at one angle of the beam. The swinging weight is bound by gravity which is downward, while the beam end moves up and down. Granted it may not be much but that depends on the amount of weight and the strength of the 'motor' that drives it.
So the cord and weight have little relationship to the beam, only to the pivot point of the cord.

I was trying to highlight the damping factor not the energy extraction.

 

The difference is that you were suggesting I didn’t understand the basics of energy conservation and were trying to find fault with what I was doing. Misterbill and a few others didn’t and were offering constructive ideas. The undertone of your posts was very different. Maybe you hadn’t read every post in the thread but I can only respond to what you put out and not what might be in your head.

OK, now we know, the TS, J.P. Is one of us who lacks the ability to read minds at a distance. I frequently need to remind folks that I am very handicapped by that same inability. Welcome to the group, J.P!

 

OK, now we know, the TS, J.P. Is one of us who lacks the ability to read minds at a distance. I frequently need to remind folks that I am very handicapped by that same inability. Welcome to the group, J.P!

It’s a failing of mine.

 

Generating electricaql energy from a slow moving object will be a challenge in efficiency because rate of change is a first order variable in the formula. That was my reason for suggesting a fluid pumping arrangement, which does not depend on speed so much.

 

Generating electricaql energy from a slow moving object will be a challenge in efficiency because rate of change is a first order variable in the formula. That was my reason for suggesting a fluid pumping arrangement, which does not depend on speed so much.

Sure. Having got a vessel full of fluid (e.g. air or water) I need to calculate the potential energy contained in it. That shouldn’t be too hard.
Interesting news on the new liquid air storage system being built: https://www.theguardian.com/environ...-liquid-air-battery-starts-construction-in-uk

 

Sure. Having got a vessel full of fluid (e.g. air or water) I need to calculate the potential energy contained in it. That shouldn’t be too hard.
Interesting news on the new liquid air storage system being built: https://www.theguardian.com/environ...-liquid-air-battery-starts-construction-in-uk

Sure, it works but it's not an efficient 'battery' technology.

https://kth.diva-portal.org/smash/get/diva2:1216213/FULLTEXT01.pdf

The biggest disadvantage of LAES is its low round trip efficiency, probably under 50%, which is much lower than that of batteries and pumped hydro. It is similar to CAES and other chemical storage. LAES is only practical on a relatively large scale. Also, concentration of oxygen and cold working temperatures pose some safety risks.

Round trip efficiency without heat and cold recycle

Figure 4 shows how the efficiency can be increased with access to waste cold. With access to waste cold the optimal P(B) changes slightly from 16,6 bar at 25 °C to 15,7 bar if waste cold at 0°C is available. The efficiency increase is modest but probably relatively easy to achieve. Without cold heat sink medium, the efficiency is 21,6% and with heat sink medium at 5 °C the efficiency is 23,1%.

 

Sure, it works but it's not an efficient 'battery' technology.

https://kth.diva-portal.org/smash/get/diva2:1216213/FULLTEXT01.pdf


Round trip efficiency without heat and cold recycle

Well scale is presumably not a problem in this example. Diversity in energy storage systems has to be a step in the right direction and necessary to suit a range of environments and contexts.

 

I notice bad behavior by several on here who brazenly making irritating comments.
It is an accusation that any claim has been made regarding the functionality or efficiency.
The discussion is negatively affected and those forcing wrongful narrative continue to disrupt.

It is not cute, not friendly, just disruptive bad actors attacking someone trying to improve a 2 stage oscillator model.
The forum suffers from their wrongful activity of disruption resulting in people get tired of them and leave the forum.
There are trolls and their activity can be seen on this thread.

The author further reveals that the mechanism itself is sufficient as a platform to study energy transfer and storage having a short undulation.
The project is somewhat like measuring bumps in a road using a detector under a moving vehicle, the handling of the data and it's accuracy being more important than structure and isolation of it's vibration could be done with software.
The question regarding a 555 timer with a transistor follower being sufficient with regard to duty cycle and frequency almost has enough
information to answer the question. I can only guess that also software and sensor could make up for inaccuracy.

 

Wasn’t for me to say but well said.

 

Well scale is presumably not a problem in this example. Diversity in energy storage systems has to be a step in the right direction and necessary to suit a range of environments and contexts.

I think it's a step in the right direction too if we have excess energy for solar or wind that can't be more efficiency stored or used by other means like smart-grids, pumped hygro or large scale batteries. At large energy scales the low efficiency solutions become environmental problems of concentrated heat waste because heat engine efficiency is fundamentally limited.

 

I notice bad behavior by several on here who brazenly making irritating comments.
It is an accusation that any claim has been made regarding the functionality or efficiency.
The discussion is negatively affected and those forcing wrongful narrative continue to disrupt.

It is not cute, not friendly, just disruptive bad actors attacking someone trying to improve a 2 stage oscillator model.
The forum suffers from their wrongful activity of disruption resulting in people get tired of them and leave the forum.
There are trolls and their activity can be seen on this thread.

I think the OPs defense of his ideas has been excellent and well said. This is the 'internet' not a church or library where people are expected to fall in line and be silent.