Hi,
Do you remember this guy? https://www.youtube.com/watch?reload=9&v=wI7j6YYZ8-I
Look at the wheel and how its made. Attached picture is his work. Not my idea. His intensions is very different from mine, but the physical construction is very similar on mine.
Instead of using water and buoyancy, I want to (first of all make a much smaller model) replace the tubes with rod magnets that is polarized through diameter - or just steel rods.
What is left outside the wheels is larger portions of visible magnets or steel rods at the narrow end, and smaller portion of visible magnets or steel rods at the wide end.
Now, if we let the magnetic poles go radially, so north is ponting outwards for all magnets.
Then fill the volume inside with ferrofluid. Or just use steel rods.
Inside the wheel the magnetic field is closed in a narrow loop that is kept inside the ferrofluid, but outside in the air the magnetic field is stretching further out.
Then we place long magnets above or under, and on the outside of the wheels along the plane with them. So now the narrow ends that expose more rotormagnet repel or attract the stationary magnets more than the wide end does.
What I try to mimick is the experiment similar to the curie point motor. Making the area ahead of the stator magnet more attractive than the area after.
It's late, so I will make some drawings tomorrow if you don't quite understand what I mean.
Here is a simple sketch with steel rods.
Steel rods as grey
Magnet
Ferrofluid as brown.
Keep in mind that the narrow and wide end of these wheels stays in the same orientation when the wheels turn.
Vidar
I made some simulations in FEMM. I can simulate in only one plane, and the depth of each parts is the samw in FEMM. That means this simulation is not telling everything.
I tried to simulate six different positions of the wheel, just to see how the Y-axis force is. At 30° angles it is lots of uncertainties wether the results ends up in wanted torque or not. I hope the attached images speaks for itself.
Vidar
The grey transparent areas in the images in previous post is the with of magnetic material in the wheel that depends on the position of the steel rod (green).
Also, the magnet at the bottom points its poles horizontally. N to the left and S to the right, or vica verca.
Vidar
Hi Vidar,
how is the ferro-fluid orientated inside the wheel?
At the narrow point is it the same volume compressed, at the wide point same volume stretched thin?
Thanks artv
Quote from: shylo on December 09, 2018, 04:20:45 AM
Hi Vidar,
how is the ferro-fluid orientated inside the wheel?
At the narrow point is it the same volume compressed, at the wide point same volume stretched thin?
Thanks artv
The ferrofluid is not compressable, so it will be filled the complete volume all the time. Since it is a fluid, it will stay oriented as this shape. The steel rods is just "floating" inside and will stirr around in the fluid.
Gaskets around each steel rod prevents fluid to escape.
Steel rods are free to move horizontally. Yellow wheels have separate angled axels (not shown) that is attached to each fixed structure.
So, there is no compression or "stretch" of this fluid.
Vidar
Shylo, this image might explain better. You see that the steel rods are submerged in ferrofluid inside between the wheels.
See explanations of principle of operation in the text in the image.
Vidar
Won't the weight of the fluid just make the wheel come to rest with the wide part at the bottom?
artv
Quote from: shylo on December 10, 2018, 03:36:10 AM
Won't the weight of the fluid just make the wheel come to rest with the wide part at the bottom?
artv
No. It can't. You see the shafts? Marked as axle 1 and 2 that is.
These shafts are connected separately to each the two wheels. As you turn the wheels around, they will turn around in two different axis that is off axis with respect to eachother, because the shafts are not aligned, but have an angle between them.
So the wide and narrow part will stay where they are even if the wheels are turning. I made a short video showing how they turn. Between the wheels I put the ferrofluid. I do ofcourse need to seal the compartment between the wheels so the fluid doesn't poor out.
https://youtu.be/R7uRDvxw1ks (https://youtu.be/R7uRDvxw1ks)
Vidar
Ok I understand your design, but I don't see why it should rotate.
It will just find balance and sit there.
The wide part stays at ~90deg. and the narrow at~270deg. why should it rotate?
artv
Quote from: shylo on December 11, 2018, 03:42:29 AM
Ok I understand your design, but I don't see why it should rotate.
It will just find balance and sit there.
The wide part stays at ~90deg. and the narrow at~270deg. why should it rotate?
artv
That has crossed my mind too, but the wide part stays at 0 ° and narrow part stays at 180° - all the time. The wide part isn't falling down to the bottom at 270°, and the narrow part isn't rising to the top at 90°. The ONLY thing that goes around is the flat disc wheels and the steel rods. The wheels is just acting as walls to keep the ferrofluid inside.
However, Im not claiming that this will work :) , but my idea is that the narrow part exposes approx 90% of the moving rods/parts to the magnetic field. At the bottom approx 50% is exposed. At the widest part 0% is exposed to the magnetic field.
Since the ferrofluid is stationary and fluid, there is no torque in this part at all. Yes, the wheels are turning, but the ferrofluid doesn't need to turn with it. However, its viscosity will finally force the ferrofluid to rotate with the wheels and rods, but that is actually not doing anything.
Since the ferrofluides shape and orientation is stationary and liquid, and the only moving/rotating magnetic parts that "changes size" is the steelrods, the stationary ferrofluid will dominate and cover for the magnetic field more and more as the rods moves from the narrow to the wide side. By doing so, less magnetic field is attracted to the bottom steel rod alone, than the field interacting with the rods earlier, closer to the narrow part, and less and less magnetic fields interact with the steel rods from the bottom toward the wide part.
The idea is that the magnetic interaction with the rods is not balanced, but insted imbalanced by attracting the moving rods more on the narrow-bottom side than the bottom-wide side.
I just got some rubber rings that I will put the steel rods through as a seal. I just need to print out a small model of the wheels, shafts etc. I got approx 50cl of ferrofluid left, so the model will be small.
I also expect more of a mess, than a working model, but it is fun to try :)
I changed my letters somehow?I think you would be better to test and see if the ferrofluid really does reduce magnetic attractionto the steel.Also any fluid will cause friction on the disks and rods.But if you do build I wish you good-luck and look forward to your results.artv
It is a mechanical and magnetic system where no new laws of physics have been claimed in order for it to work. Therefore as it is obeying the laws of mechanics and electromagnetism, it is also describable by a Lagrangian which is fully compatible and logically equivalent to a description by forces, torques and their works. Therefore there is no extra energy. It's as simple as that.
Is this "idea" claimed as a type 1 perpetual motion?
A positive answer implies that the given description of the "idea" is inconsistent for the above reason.
Is not this "idea" claimed as a type 1 perpetual motion?
Then either the "idea" is to tap an unknown energy source (a clue about which?) or the laws of mechanics or electromagnetism are indeed implicitly challenged (which ones?)
Quote from: F6FLT on December 12, 2018, 09:34:50 AM
It is a mechanical and magnetic system where no new laws of physics have been claimed in order for it to work. Therefore as it is obeying the laws of mechanics and electromagnetism, it is also describable by a Lagrangian which is fully compatible and logically equivalent to a description by forces, torques and their works. Therefore there is no extra energy. It's as simple as that.
Is this "idea" claimed as a type 1 perpetual motion?
A positive answer implies that the given description of the "idea" is inconsistent for the above reason.
Is not this "idea" claimed as a type 1 perpetual motion?
Then either the "idea" is to tap an unknown energy source (a clue about which?) or the laws of mechanics or electromagnetism are indeed implicitly challenged (which ones?)
Hi there. I haven't claimed anything. I just need to figure out how magnetism "works" on this. I know just as well as everyone else, that overunity or perpetual motion can't work.
This time I got stuck. I do not know what is happening to the device. I don't know what mechanism that counterforce the rotation, except friction. For me, as I write, I have no good reasons to why it doesn't work. I want to find that reason. To do that, I must build, because I can't simulate this.
Vidar
Quote from: shylo on December 12, 2018, 03:40:35 AM
I changed my letters somehow?I think you would be better to test and see if the ferrofluid really does reduce magnetic attractionto the steel.Also any fluid will cause friction on the disks and rods.But if you do build I wish you good-luck and look forward to your results.artv
Hi! You probably hit he B-button above the text box :-)
I have printed out the first two discs. Two more equal discs is in production. These will just laminate the first ones so the rubber gaskets doesn't fall off.
This fluid have a rather high viscosity. It is mostly oil. Friction is an issue, but also when the gaskets slides back and forth on the steel rods as the wheels rotate. The steel rods I'll be using is 304 steel (Almost stainless). They react on magnetism, but not as good as iron. More like the ferro fluid. This will help because I have only strong neodym magnets available, that would probably destroy the device by crunch it together.
I'll start with six rods on this. Few enough to feel how the magnet interact with the device at different positions/small turns. This way I will learn how the ferrofluid in combination with more or less exposed steel rods will work. So I hope the friction is low enough to sense some forces backwards and forwards as I turn the wheel by hand. I can just dream about a self running thing. I honestly cannot imagine it will work with no hands involved. Let's see how the outcome is - good or bad.
I attach a picture of the first discs with small rubber gaskets in them.
Vidar
The first obstacle I can think of is similar to the problem with the buoyancywheel in the video (First post).
Since the rods is angled relative to the wheels, one side of them (rear side relative to desired rotation), is more exposed than the other.
However if this is the case, the rods should have torque around its own axis that is going in the same direction as what I want the wheels to do. These forces probably cancles out.
The second obstacle is the ferrofluid under magnetic impact. What happens with the ferrofluid close to a magnet, is that it gets "harder" for objects to enter. The pressure in the fluid increase.
However, the narrow part has very little solids to enter, and more solid to exit at the wider part. Meaning that the buoyancy is greater at the wide side.
The third obstacle is a result of the first and second obstacle. Between the wheels, there is more surface area in front of the rods than behind them. The pressure from the ferrofluids impact with magnetism will push them backwards at the bottom. This will probably be counterforced by buoyancy differences in the second obstacle and the magnetic attraction from the narrow side.
However, if the rods weren't magnetic, it would not be attraction from the magnet, but the pressure caused by the magnet at the bottom would still be there and pushed the rods backwards.
In sum, these three obstacle is something I have been thinking of, and I assume none of them have any driving force in one or the other direction. What I got left is the difference exposed rods outside the wheels - at the narrow side versus the wide side.
Therefor I got to build it to see what is actually going on. Energy MUST somehow be conserved, right? What if it's not? ::)
Vidar
Three out of six rods isn't magnetic :'(
https://youtu.be/mtvHW5fj3Jk
I have decided to cut the three "working" rods in half. They are too long anyways.
Here is more pictures.
I am printing out a bellow in flexible material to seal the space between the wheels.
Then I put ferrofluid inside.
Vidar
Quote from: Low-Q on December 12, 2018, 11:05:46 AM
Hi there. I haven't claimed anything. I just need to figure out how magnetism "works" on this. I know just as well as everyone else, that overunity or perpetual motion can't work.
This time I got stuck. I do not know what is happening to the device. I don't know what mechanism that counterforce the rotation, except friction. For me, as I write, I have no good reasons to why it doesn't work. I want to find that reason. To do that, I must build, because I can't simulate this.
Vidar
Hi Vidar,
You are in a respectable process that I am not criticizing at all. Unfortunately, it is clear to me that the underlying physics that you are missing will prevent you from succeeding.
Sorry to sound really pretentious, but if you see a child trying to make a jigsaw puzzle, and either you know there are missing pieces or he has mixed them from other puzzles, you know he can't succeed, wouldn't you tell him?
I'm not negative, I'm positive: you do a work of remarkable competence in mechanics but not in the right direction.
The movement of permanent magnets is a matter of magnetic potential energy, as weights under the influence of gravitational potential energy. Magnets move to the region of least potential energy.
The force on them is conservative, this means that the work between two points does not depend on the path but only on the potentials of the start and end points.
For the magnets to move, there must be a magnetic potential difference between the starting point and the end point. In a cycle, the starting point is the same as the arrival point, there is no potential difference, so there is no cause for magnets to move between the two points even though they have to go through a lower or higher potential point between the two. A ferrofluid doesn't change anything, it's also submitted to this principle of magnetic potentials.
Quote from: F6FLT on December 13, 2018, 05:47:32 AM
Hi Vidar,
You are in a respectable process that I am not criticizing at all. Unfortunately, it is clear to me that the underlying physics that you are missing will prevent you from succeeding.
Sorry to sound really pretentious, but if you see a child trying to make a jigsaw puzzle, and either you know there are missing pieces or he has mixed them from other puzzles, you know he can't succeed, wouldn't you tell him?
I'm not negative, I'm positive: you do a work of remarkable competence in mechanics but not in the right direction.
The movement of permanent magnets is a matter of magnetic potential energy, as weights under the influence of gravitational potential energy. Magnets move to the region of least potential energy.
The force on them is conservative, this means that the work between two points does not depend on the path but only on the potentials of the start and end points.
For the magnets to move, there must be a magnetic potential difference between the starting point and the end point. In a cycle, the starting point is the same as the arrival point, there is no potential difference, so there is no cause for magnets to move between the two points even though they have to go through a lower or higher potential point between the two. A ferrofluid doesn't change anything, it's also submitted to this principle of magnetic potentials.
Thanks for your input. The missing physics is the very reason why I want to build this. I already know it wont work, but I need to know why. Practical experiments never lie, and is the best way to learn the truth ;)
Vidar
Hi Vidar,
You are proposing an interesting experiment. I am familiar with someone who built a bouyancy wheel like you posted at first. He built a much smaller version and did quite a bit of analysis on it. It was too small to turn under its own power but a test he did showed something interesting. He used a small DC motor to drive the wheel in one direction and turned the current down until the wheel would stop. He recorded the minimum amount of current required to keep the wheel turning. He then did the same thing turning the wheel the opposite direction. He found that it required quite a bit more current to keep the wheel turning against the direction you would expect it to go if it could power itself. He and several of us were convinced that a much larger wheel would probably turn under its own power. But the complications of building it larger got the project put on the back burner I think.
To test your device you might also try driving it one way and then the other. The only problem with that is you need to make sure your motor draws the same amount of current in both directions when loaded the same. I have worked with motors for many years and some are more efficient one way than the other. Or you could drive the wheel on one side and then drive it from the other side to keep the motor turning the same way both times.
There are several areas of that design that can add a lot of friction to the free turning of the wheel. I am afraid you will also run in to some of those areas. One improvement you have made is the idea of using a bellows between the wheels. If I recall correctly he had a solid box around the wheels with seals where the wheels met the box. He said those seals were contributing a lot of drag.
The other area of drag was the friction caused by the tubes sliding in and out of the wheels. I don't know anything about the ferrofluid. Is it slippery like a lubricant? That might help reduce the friction in this area.
Good luck,
Carroll
Quote from: citfta on December 13, 2018, 09:25:18 AM
Hi Vidar,
You are proposing an interesting experiment. I am familiar with someone who built a bouyancy wheel like you posted at first. He built a much smaller version and did quite a bit of analysis on it. It was too small to turn under its own power but a test he did showed something interesting. He used a small DC motor to drive the wheel in one direction and turned the current down until the wheel would stop. He recorded the minimum amount of current required to keep the wheel turning. He then did the same thing turning the wheel the opposite direction. He found that it required quite a bit more current to keep the wheel turning against the direction you would expect it to go if it could power itself. He and several of us were convinced that a much larger wheel would probably turn under its own power. But the complications of building it larger got the project put on the back burner I think.
To test your device you might also try driving it one way and then the other. The only problem with that is you need to make sure your motor draws the same amount of current in both directions when loaded the same. I have worked with motors for many years and some are more efficient one way than the other. Or you could drive the wheel on one side and then drive it from the other side to keep the motor turning the same way both times.
There are several areas of that design that can add a lot of friction to the free turning of the wheel. I am afraid you will also run in to some of those areas. One improvement you have made is the idea of using a bellows between the wheels. If I recall correctly he had a solid box around the wheels with seals where the wheels met the box. He said those seals were contributing a lot of drag.
The other area of drag was the friction caused by the tubes sliding in and out of the wheels. I don't know anything about the ferrofluid. Is it slippery like a lubricant? That might help reduce the friction in this area.
Good luck,
Carroll
It was more a case of working out why it would not work.
One thing low-Q needs to take into consideration is that the ferro fluid will also become magnetic around the steel pins,as the steel pins will become temporary magnets while in the magnetic field of the PMs. This in turn (virtually) increases the volume(weight) of the steel pins,and decreases the volume of the liquid ferrofluid.
So the net work done by the PMs on the steel rods on either side of the axis point sums to 0.
Brad
@Carrol
The motor used on the buoyancy wheel might suffer from the difference in efficiency. This can be adjusted on regular DC-motors by turning the commetators a little bit one way or the other, so the timing on the rotating electromagnets is equal in both directions.
The reason why his device got more volume on one side than the other, is because of the angle between the wheels. This angle also increase the surface area in front of each tube which will cause greater force in front of the tube than behind them. This counterforce is caused by the same angle that makes greater volume on the wide side than the narrow side. So these two forces adds up to zero.
Btw, even if steel rods doesn't float on water, he could likely used steel rods instead of hallow tubes.
The difference in buoyancy is the same ;)
My ferrofluid is very slippery. It is some sort of silicone oil with magnetite powder in it.
@Brad
I can absolutely agree with you. Ferrofluid becomes a magnet. Strongest closest to the PM, but it also increase the pressure in the fluid which will make the steel rods more bouyant. Therfor harder for the steel rods to displace the fluid when they enter this area of higher compression. So what the magnetic field is attracting, the increased pressure will counterforce. So I don't think the attraction at the bottom is the main obstacle, but maybe it is.
However, something must account for conservation of energy. Cannot disagree on this.
I need to say that this is just a hobby. Much of my hobbies is creating problems at will, and then try to solve them - a troublemaker that cleans up after himself :)
Vidar
3D printed bellow. I need to redo this one. Too poor bonding between the layers. And I need to extend it a bit with one more section.
https://youtu.be/qNNiBpVd5jg
Vidar
Better but still small holes. Another material, with the same printer settings.
Vidar
Finally a water proof bellow :)
I also cut the rods in two 5cm lengths.
Vidar
Quote from: Low-Q on December 13, 2018, 10:41:02 AM
@Carrol
The motor used on the buoyancy wheel might suffer from the difference in efficiency. This can be adjusted on regular DC-motors by turning the commetators a little bit one way or the other, so the timing on the rotating electromagnets is equal in both directions.
The reason why his device got more volume on one side than the other, is because of the angle between the wheels. This angle also increase the surface area in front of each tube which will cause greater force in front of the tube than behind them. This counterforce is caused by the same angle that makes greater volume on the wide side than the narrow side. So these two forces adds up to zero.
Btw, even if steel rods doesn't float on water, he could likely used steel rods instead of hallow tubes.
The difference in buoyancy is the same ;)
My ferrofluid is very slippery. It is some sort of silicone oil with magnetite powder in it.
@Brad
I can absolutely agree with you. Ferrofluid becomes a magnet. Strongest closest to the PM, but it also increase the pressure in the fluid which will make the steel rods more bouyant. Therfor harder for the steel rods to displace the fluid when they enter this area of higher compression. So what the magnetic field is attracting, the increased pressure will counterforce. So I don't think the attraction at the bottom is the main obstacle, but maybe it is.
However, something must account for conservation of energy. Cannot disagree on this.
I need to say that this is just a hobby. Much of my hobbies is creating problems at will, and then try to solve them - a troublemaker that cleans up after himself :)
Vidar
It is great to watch you carry this out to the end.
Looking forward to the outcome.
Remember,the conservation of energy only applies to a closed system.
Brad
Just remembering some things Ive seen with ferro fluid. Have you experienced ferro fluid while in proximity to a magnet? I believe it hardens up. Like in some computer controlled shock absorbers they use field coils to control the ferro fluid to control the shock absorbing feature. So as I see the wheel will need to squeeze the fluid to keep the weight of it more on one side of the wheel. If you havnt tested the fluid first(if you did I must have missed that part), Id give that a go first. With water and gravity you wouldnt have that hardening issue and the water probably squishes around better with less resistance. Nice work.
Mags
@Brad
Thanks Brad! This is a closed system, so conservation of energy is absolutely the law. Besides that, having the opportunity to print my own parts, cheap and flexible in the matter of shapes or material, is just great.
@Mags
Yes, you're right about the hardless. However, hardness is not the right term to use, because the fluid does not got denser - fluid is virtually incompressible, but the pressure in it increase when you approach a magnet.
I made a video this morning that demonstrates exactly that.
I used the cap for the ferrofluid box. Filled it with fluid, and tested two things:
One non-magnetic rod, and one magnetic rod that I just stirred back and forth.
My ferrofluid have too much oil in it, so it doesn't make these spikes you see on good ferrofluid close to a magnet.
The non-magnetic rod will not enter the fluid, because the pressure makes the rod too buoyant.
However, when I used the magnetic rod, it snapped right into the pond. Then I compared the magnetic attraction with a magnet without ferrofluid.
It is clearly less attractive inside the ferrofluid, but enough to overcome the buoyant effect.
Maybe a perfectly mixed ferrofluid, which is more magnetic, will balance the buoyant effect with attraction, so the steel rod doesn't "know" it is entering anything.
I think, however that would not make any difference for the experiments final outcome. But I just bought 400g magnetite powder so I can mix inn more magnetite into the fluid.
Estimated delivery is dec. 19th according to Ebay.
Here is the video of the ferrofluid vs magnetic, and non-magnetic steel rods:
https://youtu.be/mNQjKTvsb0k
Vidar
After lot of mess, I have filled it up completely with ferrofluid. The gaskets keeps tight, and there is no leak.
When I try to squeeze the bellow, it is a relatively great friction that release suddenly. After that, the rods slides quite easy. But the rods will get temporary stuck at the very widest side and the very narrow side, each time the gaskets in the two wheels change direction along the rods. Also, it is different friction on each side, so the rods will be pushed out one way or the other while the wheels turn. However, I need only 60° rotation to see what is happening, because it is 6 rods.
Next is to print out a structure that holds the two shafts, one for each outer wheels/discs, so they get locked in an angle of approx +/- 15° in the horizontal plane.
I will post pictures later.
Vidar
Here is a video showing the friction.
https://youtu.be/84ez50gaGEg
Vidar
That is gonna result in one big mess.
Big mess, and hard to turn, weak ferrofluid, and weak steel rods. I came up with a similar design without ferrofluid that I will test with iron filled 3D-filament.
In the images below, I have two green wheels, one red shield. This red shield is fixed and stationary. Everything is printed in magnetic materials.
I might print the blue rods as well, but I already have magnetic (weak) steel rods already from the ongoing experiment.
The red shield, as well as the wheels, takes up magnetic fields. The thought is alike the ferrofluid experiment, that the wide side takes up more magnetic fields than the narrow side.
So wide side will ofcourse be more attracted to the magnet than the narrow side.
The steel rods is as usual more exposed at the narrow side, but hidden inside the shield on the wide side.
This experiment is much smoother. The wheels can turn freely with very little friction.
This will be a great benefit when I check how the rods behave in the magnetic field as I turn the green wheels by hand.
Also, I can test one steel rod at the time without ferro fluid leaking out - because it will not be ferrofluid in it.
Another benefit, is that without the ferrofluid, it will not be areas which harden or compress due to the magnetic field.
A narrow airgap between the wheels and the fixed shield will avoid friction (last image)
I think this experiment will be very similar, given the magnetic properties.
It will be friction somewhere, but that is not important.
Most important is that low friction is beneficial in view of the experiment's goals.
Vidar
Complete structure.
The wheels are also made from magnetic material.
Vidar
Gabriel Kron said that Maxwell's laws break down, if the system has rotating parts like coils. Maybe angled magnetic fields do the same like in this machine?
He also said that if system theory shows that a system appears to have a negative resistor in it, the system will behave like there is negative resistor there. So the goal is not to find a negative resistor, but to build a system that appears to have a negative resistor in it. Making something that is not there to actually manifest the effect of such a thing. So in effect maybe you cannot build a negative resistor, but you can gain the effect of one
I picked up that iron filament today. How cool is this? :)
500g plus the spool is lifted easily with a neo-magnet.
https://youtu.be/sId01hDLIRE
I'm printing parts for the new experiment. I hope it's possible to examine the function of it.
Vidar
Quote from: Belfior on December 16, 2018, 08:07:41 AM
Gabriel Kron said that Maxwell's laws break down, if the system has rotating parts like coils. Maybe angled magnetic fields do the same like in this machine?
He also said that if system theory shows that a system appears to have a negative resistor in it, the system will behave like there is negative resistor there. So the goal is not to find a negative resistor, but to build a system that appears to have a negative resistor in it. Making something that is not there to actually manifest the effect of such a thing. So in effect maybe you cannot build a negative resistor, but you can gain the effect of one
Hi there!
I have no high hopes that this will run by itself. I build it to examine an effect that I cannot figure out. I am strictly bound to common physics, and the known laws of thermodynamics will some how account for the conservation of energy - in theory that is.
I'm not shure what Gabriel Kron meant with his statement. Is he implying that magnetic behaviour can cause things to loop itself without stopping? Like, uhh, overunity?
Vidar
Then all the rods are printed. The first wheel is now in production. One wheel takes more than 4 hours. Next wheel tomorrow.
Then I'll be gone for two days bussiness trip. Continue with the shield on thursday. Then the shaft holders and bearings on friday. Hopefully finished during next weekend.
Vidar
More updates. I managed to print the last wheel, and the ststionary shield already. Now, I'm printing holders for bearings in ABS material. These holders will be bolten on with M3 bolts - 6 on each wheel.
Vidar.
Bearing holder in progress.
Vidar
Oops! Need to adjust horizontal size compensation a bit negtive. The hole is too small. Measured 21mm, not 22...
Vidar
I need to fix the 3D printer at work. Using wooden shelves and drills to make stuff :(
Quote from: Low-Q on December 17, 2018, 04:06:51 PM
Oops! Need to adjust horizontal size compensation a bit negtive. The hole is too small. Measured 21mm, not 22...
Vidar
Looks awesome!
What make of the printer you have?
Many people missunderstand Magnetic shielding. There is no shielding just redistribution of magnetic lines. The fluid holds the rod more strongly when there is more fluid although there is less holding of the rods by the magnet. In sum the holding of the rods is the same with or without the fluid.
@Belfior:
Yes, fix that 3D printer and start building stuff :)
@telecom:
Thanks! The printer is a RepRap based one, that is built from scratch. Using Marlin firmware. No fixed or locked settings. I can do whatever I want regarding printer settings :)
@conradelektro:
I have no overunity intentions. This is a closed system, so it cannot (according to established theories) produce its own energy.
I build it just to verify a problem that I cannot solve with my mind :)
The shield is redistributing magnetic fields, and that is the problem I need an answer to.
The stationary "shield" is preferred by the magnet more at the wide side than the narrow side, because it is more magnetic mass at the wide side. However, at the narrow side I got exposed moveable magnetic rods, that also is attracted to the magnet. Since these can move, but the stationary shield cannot move, I cannot figure out how the wheels will encounter equilibrium anyways. Because, as I think, the wide side where the rods are hidden, and the stationary "shield" is the closest magnetic path, attraction between rods and magnet is least. On the contrary, the narrow side has little stationary magnetic mass, but more rotational magnetic mass.
My main goal is to learn more about magnetism. Nothing else :)
Vidar
So if we have a steel rod positioned beside a magnet, the lines of force are concentrated towards the steel rod.
Now if you bring another steel rod to the opposite side are the lines now divided between the two?
Meaning the attractive force is now half?
artv
Quote from: shylo on December 18, 2018, 03:41:24 AM
So if we have a steel rod positioned beside a magnet, the lines of force are concentrated towards the steel rod.
Now if you bring another steel rod to the opposite side are the lines now divided between the two?
Meaning the attractive force is now half?
artv
Not all the field goes through one steel rod. Rest of the field loops right back throug the air.
Adding one more rod, it willl guide some of the field too, but less density through each rod. Because one rod weaken the the field elsewhere. If you could count field lines into 10 lines. Then maybe 5 of those goes through a single rod. Adding one more rod, maybe 4 lines goes through each of them, leaving 2 lines left that loops directly through air.
I hope this explanation makes sense :)
So the widest part of my shield guides most of the field, while the hidden rod inside gets "nothing".
At the narrow side, the rod dominate the field, while less goes through the shield.
However, lots of the field goes through the wide side, leaving less on the narrow side.
But if the magnet is long, the field will "hit" the shield perpendicular to the wheels, and that, I suppose, will leave a uniform field through the whole diameter of the wheel.
Vidar
Quote from: shylo on December 18, 2018, 03:41:24 AM
So if we have a steel rod positioned beside a magnet, the lines of force are concentrated towards the steel rod.
Now if you bring another steel rod to the opposite side are the lines now divided between the two?
Meaning the attractive force is now half?
artv
I quote you again.
In my previous reply to you, I explained two rods on each side with no other magnetic objects nearby,
However, in the wheel I've designed, I assume that the narrow end rod is more magnetic attracted than the wide side rod because the stationary shield at the wide side is picking up more of the field than the narrow side. The wheels itself is also magnetic attractive, and that is the main reason why I'm confused about how equilibrium can occur.
If it's the case that one side of the rotating wheels, including rods, is more attractive on one side than the other, I will probably be killed by Big Oil ;D . However, I want to live my life, so I hope my assumtions isn't correct.
I will do some more simulations on this also, but FEMM isn't considering the magnetic field that goes "in and out" of the computer screen, only those in plane with the screen. Also, Femm cannot simulate an object that is wider on one end than the other. The defined depth of the model is fixed to the same depth all over the place, on every object. Iron, magnets, air, or what not.
Therefor, FEMM is pretty much useless to simulate a model that have magnetic fields in three dimensions. So I must try to make a simulation, or several, for it to make sense. However, the best "simulation" is building the thing and get it over with.
Now, I'm resting on a hotel after 7 hours driving. Some dinner now, and I will start simulating more while am not at home and able to do any work on my model.
Vidar
So the magnetic pull never weakens no matter how many avenues we give it?
As long as they are of the same orientation?
artv
Quote from: shylo on December 18, 2018, 05:44:31 PM
So the magnetic pull never weakens no matter how many avenues we give it?
As long as they are of the same orientation?
artv
I would say that the magnetic pull on one single steel rod weakens if you introduce another steel rod, but not as much as half. Both will have a combined pull greater than one single steel rod, but not double the force.
Vidar
Finally some bearing holders that fits.
PS! The picture of a spinning disc, spins because I spun it by hand. Just for illustration.
Vidar
I must make a rod controller so the rods doesn't slide out.
Attached image is from SketchUp Make. It is made of semi flexible material.
Fexing material is necessary because the rods does not follow a circular path due to the angle between the wheels.
Each rod is placed centered in each hole
Vidar
have you thought about magnetic bearings, so the thing just floats? I think I need to give them up. Just a bit of rotation and the thing flies off the bench :(
Spinning an all north field, creates a south field out in front of the spinning north
The distance away from the spinning field, determines on the strength of the magnet's that are spinning
Vidar
Just mount a retainer on either side to prevent the rods from traveling too far.
Nice work
artv
Quote from: Belfior on December 21, 2018, 07:30:22 AM
have you thought about magnetic bearings, so the thing just floats? I think I need to give them up. Just a bit of rotation and the thing flies off the bench :(
I don't think magnetic bearings will do any good. These baallbearings that I have, have no longer grease in them, so they spins very easily.
Vidar
Quote from: shylo on December 21, 2018, 01:32:40 PM
Spinning an all north field, creates a south field out in front of the spinning north
The distance away from the spinning field, determines on the strength of the magnet's that are spinning
Vidar
Just mount a retainer on either side to prevent the rods from traveling too far.
Nice work
artv
I do not understand the first paragraph ???
Retainers will help :) , bu I'll try this holey rod holder first.
Vidar
Then the structure to hold the shafts and the shields is finished. Not good quality since I printed too fast, too low temperature. Anyways, it holds the wheels and shield good enough.
The flexible rod holder didn't worked, so I'm printing two 15° cones that holds the rods. These cones fits between the wheels, and will roll along the inside without wobbeling from side to side.
I also have to make a stronger magnet. Stacking those discmagnets, and configure them as an hallbach array. I will show you how later.
Here is a couple of new pictures.
Vidar
I'm not sure if these are any help to you, but Laithwaite has many videos on youtube, that gave me many ideas on magnetics
https://www.youtube.com/watch?v=oWiYsRi2Dss
Quote from: Belfior on December 26, 2018, 07:53:42 AM
I'm not sure if these are any help to you, but Laithwaite has many videos on youtube, that gave me many ideas on magnetics
https://www.youtube.com/watch?v=oWiYsRi2Dss (https://www.youtube.com/watch?v=oWiYsRi2Dss)
I watched the video in your link. Very interesting stuff. If I just could get my magnets to behave like AC-coils.
Vidar
New update on the project. It didn't worked out as I hoped. So new parts is printed to achieve better alignment and much less friction.
As said before, the exposed rods at the narrow side was assumed to be pulled more than the hidden rods at the wide side, where I also could not figure out what counter force which stops the rotation. However, some misalignments, and too short rods, prevents a good analysis of whats going on.
Here is a short video, in poor slow english ( ;D )...
https://youtu.be/hxgRHdQeN44
Vidar
I am still so jealous of your 3D printer, that cannot even watch the whole video :(
I will attach a picture of my PM motor, that was not made with a 3D printer (and for that reason is not quite ready yet :( )
The only way I could see the device working, is that the PM magnets get pulled towards the magnet below them. When they approach the bottom magnet, they also get closer to each other. You can probably get them ALL not to repel, but not really care about each other. I think you might call it like a halbach array when they all meet at the bottom. No magnetic field to notice and magnets at the top are being pulled or pushed.
So magnets get pulled down towards the bottom magnet. On the other side of the wheel they are pushed up. When they meet at the bottom, the field is made smaller than the pushing field by arranging the magnets. This would supply the rotation.
My own version relies on acceleration. My wheel accelerates the whole rotation and at the cogging point this angular momentum should carry it over the cogging magnet and to a new rotation. I might need to add an electromagnet so help also at the cogging point or on the other side of the rotor. The third aide is a coil system on the rotor middle. Moving coil (on rotor that moves) inside a changing magnetic field should induce a current into that coil. Now you got Lorentz force in play. You can arrange the setup so, that you get positive Lorentz force that helps with the rotor rotation.
So I hope angular momentum, electromagnet and Lorentz will help with the cogging. Maybe there are more forces I could cram in there.
Quote from: Belfior on December 27, 2018, 07:41:32 AM
The only way I could see the device working, is that the PM magnets get pulled towards the magnet below them. When they approach the bottom magnet, they also get closer to each other. You can probably get them ALL not to repel, but not really care about each other. I think you might call it like a halbach array when they all meet at the bottom. No magnetic field to notice and magnets at the top are being pulled or pushed.
So magnets get pulled down towards the bottom magnet. On the other side of the wheel they are pushed up. When they meet at the bottom, the field is made smaller than the pushing field by arranging the magnets. This would supply the rotation.
My own version relies on acceleration. My wheel accelerates the whole rotation and at the cogging point this angular momentum should carry it over the cogging magnet and to a new rotation. I might need to add an electromagnet so help also at the cogging point or on the other side of the rotor. The third aide is a coil system on the rotor middle. Moving coil (on rotor that moves) inside a changing magnetic field should induce a current into that coil. Now you got Lorentz force in play. You can arrange the setup so, that you get positive Lorentz force that helps with the rotor rotation.
So I hope angular momentum, electromagnet and Lorentz will help with the cogging. Maybe there are more forces I could cram in there.
I don't quite understand how the rotor magnets is getting closer to eachother at the bottom. If they do, I assume the rotational speed isn't constant. So the rotating magnets creates a "traffic jam" at the bottom (?)
I do not use rotating magnets btw., just ferromagnetic rods. Maybe you explained your own project?
I have been thinking of using rotating magnets, but I feel that I have spent enough time and ideas on that, and came to the conclusion that rotating magnets doesn't work. However, it doesn't hurt to try more.
Cogging should not be a problem. Even if it is cogging, this is a response to sticky or repelling spots along the revolutions. Usually, this cogging is due to forces that is equal and opposite in front and behind the very spot where the cogging is at its peak. So the cogging itself should not drain or add energy into the system. For a smoother rotation, it will help with an electromagnet, but then you supply energy into the system due to electrical loss in the electromagnet.
Vidar