https://www.youtube.com/watch?v=W6SSY7ABJkw (https://www.youtube.com/watch?v=W6SSY7ABJkw)
Check this thing out. I know it has been out for a while, and a guy had one at work last year on his desk. It is amazing and, I would like to make one as it costs about $100 US to buy. The video above says it all. It even works sideways!
To me, this is the opposite of the kind of devices that TK, Lidmotor and others have built where something hangs in space using light sensors.
I am guessing that there is only about $10-$20 worth of parts in this thing. I just think it would be really cool to make one.
TK suggested searching for their patent to see what that says. This is a good idea and I will look for it.
Bill
PS It also rotates the levitating disk as well as adjusts for any added weight differential. Amazing!
PPS: I found this while searching: US patent number 2007/0170798A1. I will pull it up to see what it says.
I found this:
http://www.google.com/patents/US20070170798 (http://www.google.com/patents/US20070170798)
Very interesting to read. I am just getting started with it.
Bill
I haven't read the patent yet but here's what I think.
The black disc contains a big ring magnet polarized on the faces, and a couple smaller magnets around the edge of the ring, but facing sideways. The base contains a big coil facing up/down, and a few smaller coils around the edges. The big coil is switched in polarity, rather then being just turned off and on as in my levitation system. The opposite switching polarities of the big coil act on both poles of the ring magnet to "lock" it into position, whereas in the usual system like mine, the levitated object is not locked but rather balanced between gravity pulling it down, and magnetism pulling it up. It's always falling slightly when the coil is off and rising slightly when the coil is on. But in the Levitron, gravity doesn't play a role, the thing is first attracted-repelled by one polarity of the coil acting against the faces of the ring magnet and then attracted-repelled oppositely by the other polarity of the coil. So it's "locked" in position. The rotation and perhaps lateral stabilization come from the side-facing magnets in the black disc, the rotation coming from being slowly attracted or repelled by the smaller coils around the outside of the big coil in the base, in ordinary "pulse motor" fashion. This locking in position, regardless of direction of gravity, can be seen in my demonstration of what I call the "Nikolayev trailer hitch", where a ring magnet and a cylinder magnet are kept in that relationship, and the cylinder is prevented from flipping over by being inside a central tube. In the Levitron the black levitating disc doesn't flip over because the polarity of the coil is flipping over instead. The spacing is probably maintained by photodetectors and UV or IR LEDs, and the visible LEDs are there to tell the operator when the disk is in the correct position for the sensing system to take over.
That's my guess.
Now I suppose I should read the patent.
(There is another really cool levitation system that works by having most of the weight of the levitated object taken up by a strong Permanent Magnet in the top of the assembly, and the electromagnet coil is wrapped around the PM. The strength of the overall field of the PM/coil is regulated in the usual way by sensing shadow edge or by Hall sensor, and it takes very little current in the coil to maintain the levitation. If the power goes off, the levitated object doesn't drop like it does in the usual system like mine, but rather is pulled UP to the permanent magnet in the top part of the device. It also will "self start" from this position when the power is turned on, it doesn't need any intervention from the operator to get things in the right position. This system is much more efficient than the usual one since it takes so little current to regulate the field of the PM that is supporting the weight of the object.)
ETA: now I've read the patent. I almost guessed it! It looks like sort of a combination of what I guessed and the other system mentioned above, partially permanent magnets and partially coils modulating the field of the PMs.But I had the base and disc PM configurations reversed, apparently, from what's in the patent.
Good find Bill, thanks!
Yes, there are few strong permanent magnets and with sensor usage it just balances the object all the time with weak electromagnets.
Click on this Link to see the Patent in a PDF format that's easier to read.
http://www.pat2pdf.org/patents/pat20070170798.pdf (http://www.pat2pdf.org/patents/pat20070170798.pdf)
.
Quote from: TinselKoala on November 25, 2014, 11:12:15 PM
I haven't read the patent yet but here's what I think.
The black disc contains a big ring magnet polarized on the faces, and a couple smaller magnets around the edge of the ring, but facing sideways. The base contains a big coil facing up/down, and a few smaller coils around the edges. The big coil is switched in polarity, rather then being just turned off and on as in my levitation system. The opposite switching polarities of the big coil act on both poles of the ring magnet to "lock" it into position, whereas in the usual system like mine, the levitated object is not locked but rather balanced between gravity pulling it down, and magnetism pulling it up. It's always falling slightly when the coil is off and rising slightly when the coil is on. But in the Levitron, gravity doesn't play a role, the thing is first attracted-repelled by one polarity of the coil acting against the faces of the ring magnet and then attracted-repelled oppositely by the other polarity of the coil. So it's "locked" in position. The rotation and perhaps lateral stabilization come from the side-facing magnets in the black disc, the rotation coming from being slowly attracted or repelled by the smaller coils around the outside of the big coil in the base, in ordinary "pulse motor" fashion. This locking in position, regardless of direction of gravity, can be seen in my demonstration of what I call the "Nikolayev trailer hitch", where a ring magnet and a cylinder magnet are kept in that relationship, and the cylinder is prevented from flipping over by being inside a central tube. In the Levitron the black levitating disc doesn't flip over because the polarity of the coil is flipping over instead. The spacing is probably maintained by photodetectors and UV or IR LEDs, and the visible LEDs are there to tell the operator when the disk is in the correct position for the sensing system to take over.
That's my guess.
Now I suppose I should read the patent.
(There is another really cool levitation system that works by having most of the weight of the levitated object taken up by a strong Permanent Magnet in the top of the assembly, and the electromagnet coil is wrapped around the PM. The strength of the overall field of the PM/coil is regulated in the usual way by sensing shadow edge or by Hall sensor, and it takes very little current in the coil to maintain the levitation. If the power goes off, the levitated object doesn't drop like it does in the usual system like mine, but rather is pulled UP to the permanent magnet in the top part of the device. It also will "self start" from this position when the power is turned on, it doesn't need any intervention from the operator to get things in the right position. This system is much more efficient than the usual one since it takes so little current to regulate the field of the PM that is supporting the weight of the object.)
ETA: now I've read the patent. I almost guessed it! It looks like sort of a combination of what I guessed and the other system mentioned above, partially permanent magnets and partially coils modulating the field of the PMs.But I had the base and disc PM configurations reversed, apparently, from what's in the patent.
Good find Bill, thanks!
TK:
That was a very well educated guess on your part. The patent did not seem to me to be very clear but, the info is there and, I suppose they don't want to make it easy for folks to make on their own. What is doing the polarity switching? Is it a mosfet or something? It seems that it would have to handle a lot of power. As a matter of fact, one of the things I found was a review from a guy that said his device worked great for 3 days after he bought it...then...it died. Maybe the switching circuit can not handle the power very well?
Also, I did not know that swapping the polarity of the input to an electromag changed the poles of the magnet. It makes perfect sense, I just never knew that. So, it ignores gravity and repels/attracts in a very fast cycle and the permanent mags are there to keep the disk centered. I wonder if someone made one of these using very powerful neos and, boosted the electromag output if it would hover a lot higher? I would not even mind a larger base with a very good heat sink and possibly even a cooling fan if needed.
No matter what, I have to say that this is a very clever application of known effects and they deserve a lot of kudos for inventing it. I love this type of thing.
Bill
PS Fatbird: Thanks for the PDF.
Quote from: pavqw on November 26, 2014, 02:05:04 PM
Yes, there are few strong permanent magnets and with sensor usage it just balances the object all the time with weak electromagnets.
It does more than "just balance" because it supports the levitated disc even when the base is turned on its side. It actually locks the disc in position, up down and sideways.
It's a really neat use of magnetic fields. I hope Bill buys one and tears it apart!
Quote from: TinselKoala on November 26, 2014, 09:50:25 PM
It's a really neat use of magnetic fields. I hope Bill buys one and tears it apart!
TK:
Well, I was hoping that you would buy one and tear it apart, ha ha. Hey, maybe we can start a crowd funding campaign in order to raise the $100 needed to purchase one? If we accidentally get $200,000, we can move to Morocco.
Bill
Quote from: Pirate88179 on November 26, 2014, 08:52:15 PM
TK:
That was a very well educated guess on your part. The patent did not seem to me to be very clear but, the info is there and, I suppose they don't want to make it easy for folks to make on their own. What is doing the polarity switching? Is it a mosfet or something? It seems that it would have to handle a lot of power. As a matter of fact, one of the things I found was a review from a guy that said his device worked great for 3 days after he bought it...then...it died. Maybe the switching circuit can not handle the power very well?
Yes probably it died from heat buildup. The circuits given in the patent aren't complete of course, they just show the critical parts. The triangle symbols are op-amp comparators that will flip output polarity based on what happens at their two inputs. They could be high-power opamps that drive the electromagnets directly, or they could drive a current amplifier stage, like an H-bridge of bipolars or mosfets, that then drive the coils. It would be fun to examine an actual conventional schematic instead of the patent-type sketches of the circuitry.
Quote
Also, I did not know that swapping the polarity of the input to an electromag changed the poles of the magnet. It makes perfect sense, I just never knew that. So, it ignores gravity and repels/attracts in a very fast cycle and the permanent mags are there to keep the disk centered. I wonder if someone made one of these using very powerful neos and, boosted the electromag output if it would hover a lot higher? I would not even mind a larger base with a very good heat sink and possibly even a cooling fan if needed.
Yes, it's got me thinking too. I imagine that it wouldn't really be too hard to build something similar, now that we have the "hints" in the patent. I might even have some magnets that would be appropriate, like a big ring magnet, and another thin flat-plate thing that is amazingly strong, originally meant for attaching a tracking device underneath a car body. I dunno if I have the patience to make a functional version but I might do some "proof of concept" experimenting later on.
Quote
No matter what, I have to say that this is a very clever application of known effects and they deserve a lot of kudos for inventing it. I love this type of thing.
Bill
PS Fatbird: Thanks for the PDF.
Dittoes. I'd like to see how fast the spinning could be made to go; it's regulated to be slow in the device as we see it, I think, since it's designed to display stuff rather than do crazy fast spinning.
Quote from: Pirate88179 on November 26, 2014, 09:55:33 PM
TK:
Well, I was hoping that you would buy one and tear it apart, ha ha. Hey, maybe we can start a crowd funding campaign in order to raise the $100 needed to purchase one? If we accidentally get $200,000, we can move to Morocco.
Bill
;D ;D ;D ;D ;D
In my continued searching on the Levitron, I am reading more and more reviews where it breaks down after only a few days. There are quite a few complaints of this nature. They also make a levitating globe which is a little smaller device using the same approach, and I also read at least 3 reviews where that one quit working after just a few days. If I paid $100 or so for this and it broke after a few days, I would be sending it back.
I have not yet found where anyone has taken the base apart and video taped it or took photos.
I will continue to search.
Bill
It is not that hard to built one.
You will need hall sensor(s), coils A, B and some neodymium magnets.
There must be exact proportion between all these stuff to get the best results.
With microprocessor you can do it even more sophisticated.
It would be nice if permanent magnet can be replaced with electromagnet to change levitation height. With this you can make even cooler levitated platforms.
But if you want to really levitate things, I can see much higher potential in ion thrusters.
I am now thinking that maybe...possibly, I can convert one of my one magnet, no bearing Bedini motors (Ala Johnnydavro) into one of these levitrons? It has the electromagnetic coil placed vertically, and the circuit to pulse it....I think we need to find out a way to swap polarities on the electro mag and also add some stabilization perma mags around the base.
It might be easier to start from scratch but this idea hit me today and I am still thinking about it.
Bill
One of my videos of the Johhnydavro replication: https://www.youtube.com/watch?v=8RsFMyZbj1I&list=UU0bTBCRogMzrYTQT3pbhxwg (https://www.youtube.com/watch?v=8RsFMyZbj1I&list=UU0bTBCRogMzrYTQT3pbhxwg)
Bill, the way to do it is to use an H-bridge, or equivalently an op-amp circuit, that will switch output polarity in response to a sensor input. Two example "sketches" are below. Just substitute the coil for the motor M in the circuits. These are bare-bones sketches of course, the real circuit will have some more complexity depending on your sensors, power supplies, etc.
You'd need relatively highpower op-amps that can source and sink sufficient current on the outputs to the coil. Like maybe OPA549 from TI.
Here's a more complete and simpler solution but requires a bipolar power supply, +/- voltage wrt a "zero" ground level. The 741 op amp is as common as sand and about as cheap.
If Vin to pin3 of the 741 is above the ground level the motor or coil runs one way, if the Vin is below the ground level the motor or coil runs the other way. The Vin comes from a potentiometer voltage divider (ends to Vcc+ and Vcc-, wiper to Pin3) or other sensor system.
Quote from: TinselKoala on November 28, 2014, 11:42:38 PM
Bill, the way to do it is to use an H-bridge, or equivalently an op-amp circuit, that will switch output polarity in response to a sensor input. Two example "sketches" are below. Just substitute the coil for the motor M in the circuits. These are bare-bones sketches of course, the real circuit will have some more complexity depending on your sensors, power supplies, etc.
You'd need relatively highpower op-amps that can source and sink sufficient current on the outputs to the coil. Like maybe OPA549 from TI.
TK:
Thank you for the schematics. This is now over my head but, I will research more on this. I am surprised that the levitron folks are not using a chip of some kind...but...maybe they are...we don't know what is inside there for sure. I am also not seeing how they are using sensors as, the base only shows leds pointing up.....maybe ir like you said before but, would the sensors not have to shoot across the bottom of the hovering base? (In a horizontal fashion) If they are just pointing up, how can they sense if the disk is rising or falling? Do you think they might be angled a bit so the light bounces off of the bottom of the disk? (and hits the receptor at a certain angle) If the disk gets too high the light misses the receptor...same if it gets too low?
I don't know why I am so fascinated by this...probably because I can't understand it...ha ha.
Maybe someone will chime in here who has one and has taken it apart. Or, maybe i can try to contact some of those folks that said in their reviews that it quit working after a few days and see if they want to make a few bucks on the now useless unit?
Bill
Quote from: Pirate88179 on November 29, 2014, 01:20:03 AM
TK:
Thank you for the schematics. This is now over my head but, I will research more on this. I am surprised that the levitron folks are not using a chip of some kind...but...maybe they are...we don't know what is inside there for sure. I am also not seeing how they are using sensors as, the base only shows leds pointing up.....maybe ir like you said before but, would the sensors not have to shoot across the bottom of the hovering base? (In a horizontal fashion) If they are just pointing up, how can they sense if the disk is rising or falling? Do you think they might be angled a bit so the light bounces off of the bottom of the disk? (and hits the receptor at a certain angle) If the disk gets too high the light misses the receptor...same if it gets too low?
I don't know why I am so fascinated by this...probably because I can't understand it...ha ha.
Maybe someone will chime in here who has one and has taken it apart. Or, maybe i can try to contact some of those folks that said in their reviews that it quit working after a few days and see if they want to make a few bucks on the now useless unit?
Bill
Well, the video shows that the disk has to be pretty carefully positioned over the base for the thing to "catch" initially, using the corner visible LEDs as indicators. Those LEDs could be part of the sensor system, or it could use Hall effect sensors somehow. The patent shows some LEDs and maybe photodiodes in the sensor loop, but just as sketches, not real complete circuits. I can think of a couple of ways that converging and reflected LED beams could be used.
Contacting someone with a failed unit might be worth doing, if they haven't been able to get any satisfaction from the distributor as far as returns go. It would be interesting to see what they are using. There are several "chips" that could handle most of the functions: quad op-amps or even motor controller chips. The high power op amp I listed earlier is kind of like a many-pin TO247 package, like a big mosfet.
I went ahead and put together that last circuit I posted, just as a lark, to see how it worked. I made a little demo video, it should be ready to view in an hour or so once it finishes rendering and uploading. It's easy and works great, with a potentiometer input. I haven't tried using it with a Hall sensor but it occurs to me that maybe the sensor from a computer fan might be made to work, like the one I used for the magnet polarity indicator. I dunno, I'll have to think about that one. For sure it will work with a 2-photocell (photoresistor type) voltage divider. I'll post the link to the video when it's done.
ETA: Here's the video:
http://www.youtube.com/watch?v=-hNEpCwRX_k
--
Quote from: TinselKoala on November 29, 2014, 02:43:35 AM
Well, the video shows that the disk has to be pretty carefully positioned over the base for the thing to "catch" initially, using the corner visible LEDs as indicators. Those LEDs could be part of the sensor system, or it could use Hall effect sensors somehow. The patent shows some LEDs and maybe photodiodes in the sensor loop, but just as sketches, not real complete circuits. I can think of a couple of ways that converging and reflected LED beams could be used.
Contacting someone with a failed unit might be worth doing, if they haven't been able to get any satisfaction from the distributor as far as returns go. It would be interesting to see what they are using. There are several "chips" that could handle most of the functions: quad op-amps or even motor controller chips. The high power op amp I listed earlier is kind of like a many-pin TO247 package, like a big mosfet.
I went ahead and put together that last circuit I posted, just as a lark, to see how it worked. I made a little demo video, it should be ready to view in an hour or so once it finishes rendering and uploading. It's easy and works great, with a potentiometer input. I haven't tried using it with a Hall sensor but it occurs to me that maybe the sensor from a computer fan might be made to work, like the one I used for the magnet polarity indicator. I dunno, I'll have to think about that one. For sure it will work with a 2-photocell (photoresistor type) voltage divider. I'll post the link to the video when it's done.
ETA: Here's the video:
http://www.youtube.com/watch?v=-hNEpCwRX_k (http://www.youtube.com/watch?v=-hNEpCwRX_k)
TK:
That is a really cool circuit. Once I watched the video, it became clear to me on how this thing works. I think that the bottom surface of the floating disk has a mirrored surface and the leds/senders/receptors could be angled to shoot up at a slight angle such that the beams bounce back down to the other side of the base to each other.
_________ (levitating disk)
. .
. .
. .
. .
. .
[--0---------------------0--] (base)
Led Sensor
Something like the crude drawing above maybe?
Thank you for making that circuit and the video.
Bill
You're welcome, it's fun to play with.
Yes, that reflection idea is one that might work indeed.
I just made another video using CdS photoresistors instead of the potentiometer, it's uploading now. I'll put a link when it's ready. Still haven't tried it with a coil but that's coming soon.
ETA: Video:
http://www.youtube.com/watch?v=SUsA-YuAtBU
Magnet hopper:
http://www.youtube.com/watch?v=onga0XPFs44
:P
Quote from: TinselKoala on November 29, 2014, 04:45:57 PM
Magnet hopper:
http://www.youtube.com/watch?v=onga0XPFs44 (http://www.youtube.com/watch?v=onga0XPFs44)
:P
I commented on your video and don't want to repeat myself but.....this is excellent! Clearly showing the pole reversal on the coil controlled by your photo sensors. What ga. wire is on your coil? Also, do you have an iron core in the coil?
This is so cool to watch you reverse engineer this device. I hope a lot of folks are watching this.
Bill
#33, no core, perhaps 1500 turns, it's one of the test coils I made for the PerPenduPetulum. Its resistance is too high, really, which is why it doesn't burn out the transistors by drawing too much current. They don't even get warm. For a real levitator you'd want to use heavier wire to get more current, and power transistors or mosfets. Also I think the CdS sensors might not be optimum. Probably better to use phototransistors or photodiodes, or even a specialized Hall effect sensor system. I'm still thinking about all of that.
Quote from: TinselKoala on November 29, 2014, 04:45:57 PM
Magnet hopper:
http://www.youtube.com/watch?v=onga0XPFs44
:P
Very cool TinselKoala Put a fan blade (or your flat piece of wood) on the motor so when the fan covers the sensor it will reverse and cover the other one and reverse again. Why no idea :-) but would be fun to watch.
I guess you could also try throwing a bar magenet in your coil and create a bidirectional solenoid. Put sensor top and bottom so when the magnet pokes out one side polarity reverses and hopefully catches it in time and forces magnet out the other side of the coil and repeats. Again no idea but would be fun to watch.
Quote from: Nink on November 29, 2014, 11:25:12 PM
Very cool TinselKoala Put a fan blade (or your flat piece of wood) on the motor so when the fan covers the sensor it will reverse and cover the other one and reverse again. Why no idea :-) but would be fun to watch.
I guess you could also try throwing a bar magenet in your coil and create a bidirectional solenoid. Put sensor top and bottom so when the magnet pokes out one side polarity reverses and hopefully catches it in time and forces magnet out the other side of the coil and repeats. Again no idea but would be fun to watch.
Ah... great minds think alike. Actually one of my YT subscribers m3sca1 suggested this first, although I was already thinking of it. So yes, I did it, sort of, and it works. I call it the MescalMotor in his honor... sorry, I already named it before I saw your post! Next version may be the NinkMotor. I made a video and when it is done rendering and uploading I'll post the link here.
Again, thanks for the suggestions!
ETA: Video is up:
http://www.youtube.com/watch?v=ZqtKoFifby0
8)
Quote from: webby1 on November 29, 2014, 08:18:05 PM
I liked the first vid with the motor,, the chopstick you were using was making it move,, I had to watch it twice just to make sure I was not just seeing things :)
Yes, the photoresistors and op-amp make it very sensitive, it responded even to the very thin shadow of the chopstick!
Wow works better than I thought it would. Nice work. I may try building one with a couple of hall switches next week (wife has me doing Christmas lights this weekend )
Horizontal mounting:
http://www.youtube.com/watch?v=cgikT9HEiyM
Draws about 50-60 mA at +/- 13.5 V wrt 0 reference, and the little transistors I used are hot but not scorching.
(BC556B and BC337-25)
Quote from: TinselKoala on November 30, 2014, 08:54:46 PM
Horizontal mounting:
http://www.youtube.com/watch?v=cgikT9HEiyM
Draws about 50-60 mA at +/- 13.5 V wrt 0 reference, and the little transistors I used are hot but not scorching.
(BC556B and BC337-25)
Nice did you stick it on a sessaw and see if it would balance ?
Quote from: Nink on November 30, 2014, 10:21:27 PM
Nice did you stick it on a sessaw and see if it would balance ?
No but I'm sure it could be made to do so.
One thing that may not be obvious is that it would not work with a simple bar magnet in there. The magnets stuck onto the rod ends are oriented like this:
N:S===[[[[[coil]]]]]]===S:N
So that the coil always attracts from one side and repels from the other side. When the coil reverses polarity, the attraction/repulsion sides swap ends.
I could only find one hall sensor so I had to improvise so a small magnet retracts the other magnet when the power is cut and then power restored electric magnet is stronger than small magnet so pushes out again. Needs tweaking. https://vine.co/v/Ovz6zaVI7Yu
I guess back to the original problem how do you levitate, There are a bunch of circuits on line to levitate from above using hall or photo sensors http://www.electroschematics.com/6306/magnetic-levitation-circuit/ but not from below. I think maybe 3 or 4 hall switches coils and permanent magnets.... anyone given this any thought ?
Nink:
They way we think the electronic levitron might work is using a circuit like TK has made...then use 2 photo sensors and 2 light sources aimed at the bottom of the levitating disk. Also, there seems to be an array of perma mags situated around the base to keep the disk from sliding off to one side or the other.
I believe TK has broken this "secret" wide open by postulating that an electromagnet was being controlled by sensors and was switching polarity such that, it keeps the floating magnet disk...floating. Then he built that circuit in his videos demonstrating how it could be done. I think his "Jumping disk magnet" video shows clearly how this could work.
We know that there are permanent magnets involved in the base as evidenced by when the device is placed on its edge in the video and the disk continues to hover in place.
I think it would be cool if we started seeing homebrewed hovering devices popping up on the web.
Bill
Quote"anyone given this any thought?"
I'd bet these guys have....
https://www.youtube.com/watch?v=1gMMM62NC-4 (https://www.youtube.com/watch?v=1gMMM62NC-4)
And considering the efficiency gains and economy of the Fe16N2 magnets being constructed, which have proven appreciably stronger than the former theoretical limit, dramatic changes across the board are afoot....
http://phys.org/news188458077.html (http://phys.org/news188458077.html)
Good Journies
Quote from: TechStuf on December 01, 2014, 09:10:29 PM
I'd bet these guys have....
https://www.youtube.com/watch?v=1gMMM62NC-4 (https://www.youtube.com/watch?v=1gMMM62NC-4)
And considering the efficiency gains and economy of the Fe16N2 magnets being constructed, which have proven appreciably stronger than the former theoretical limit, dramatic changes across the board are afoot....
http://phys.org/news188458077.html (http://phys.org/news188458077.html)
Good Journies
Wow! Excellent find! (ref. the first video link) This is exactly the type of device being discussed here except, this one looks better and able to hover much, much heavier weights. Totally cool...it is getting better and better.
Thanks for posting this.
Bill
PS Here is the site of the folks that make this cool device: http://www.crealev.com/
They seem to make a lot of other related stuff too. I did not see a price for this...I get the feeling that they do custom stuff for branding, trade shows, etc. I wonder if this violates the Levitron Patent? Or, are they licensed under it maybe? Or, since it is so much better, maybe have their own patent?
CLM 1.5 Levitation Module (floating height max 70 mm) The CLM 1.5 is the long awaited module between the heavy lifting CLM 2 and the workhorse that is the CLM 1+. It's featuring levitation height of approximately 70 mm and is capable of carrying loads up to 4 kg, and is brand new for 2014! The CLM 1.5 is providing a cost effective alternative to the CLM 2 for the heavier projects. Although some characteristics are new, it still boasts all the quality one can expect from our modules. Equipped with overheating protection and based on our field-proven durable levitation technology, the CLM 1.5 is a robust and easy to use system. It has an unsurpassed levitation height for its class.
The CLM 1.5 levitation module is operated by connecting the base to a supply (mains adaptor). Next putting the carrier, with its rubber side down, in the middle above the base until "lock" occurs. The carrier can then be released. Both carrier and base contain powerful magnets, therefore Crealev advises to keep magnetic sensitive devices such as credit cards at a minimum distance of 25 mm (<300 Gauss) from the CLM 1.5.
(http://www.crealev.com/wp-content/uploads/2014/01/pdf.png)download product sheet
(http://www.crealev.com/wp-content/uploads/2014/04/CLM-1.5-Product-Sheet.pdf)
@ All: http://www.crealev.com/product/clm-1-5-levitation-module/ (http://www.crealev.com/product/clm-1-5-levitation-module/)
I like how it says it is protected from over heating! This seems to be a bit of a problem with the levitrons it seems. OK, now I really want to take one of these apart, ha ha.
Bill
They have to be using hall sensors or reed switches since they put it in a pillow etc so I agree Pirate88179 your probably looking at a circle of magnets with the ring magnet and hall hall sensor in in the corners with coil magnets making small adjustments to the voltage to ensure ring magnet is always locked. So maybe we need a broken microwave to salvage a large ring Magnet from and some computer cooling fans for hall switches.
EDIT: I THINK I WAS WRONG ABOUT THIS. I posted later that there looks to be a hole in the pillow and the table also had a hole in it for an optic sensor.
Yep. A single ratiometric Hall sensor feeding an op-amp comparator with adjustable setpoint, the comparator then drives the pushpull coil driver stage. The ratiometric Hall sensor will put out a voltage that is proportional to the sensed magnetic field strength. So you adjust the setpoint voltage so that the comparator flips at the field strength corresponding to the right levitation distance. Closer (stronger) means the push-pull output stage pushes, farther (weaker field) means that the push-pull stage pulls. (this is assuming the drive coil is beneath the levitated magnet disc). So in this manner the levitated object will be "locked" into a narrow zone, the height of which is adjustable by the setpoint of the comparator flipping state. It still must be stabilized sideways though.
For levitation coil above the object, you only need to "pull". In fact if you aren't concerned about sideways levitation, even the coil-beneath only needs to push, but for that arrangement there must be some other means, like side magnets or coils, to keep the object centered above the coil instead of slipping off like you see in the "magnet hopper" video. Of course the levitated magnet must also be prevented from flipping over in both cases; this is easily enough done by the geometry (distribution of mass wrt the distribution of lift) of the levitated object.
The only Hall sensor I have available at the moment is the one I pulled from the computer fan and it's a latching switch type, not ratiometric. Allegro Microsystems makes the ideal sensors for this purpose, they are cheap and robust and I've used them in several projects before, but I can't remember where they are at the moment. Oh... I just remembered, at least one is in the Orbette pulse motor, but I can't get to that one right now.
My Arduino-based levitator (coil on top) uses optical sensing, a really neat system that actually shuts off the illuminating LED and samples the ambient light every 100 pulses and adjusts for it automagically.
I'm not sure how the Hall sensors will work in the presence of the strong PMs and also the variable field from the coil, though. Perhaps the Hall sensor reads when the coil is momentarily off. Things can happen very fast, at multi-kHz frequencies, so you can turn coils off for a few cycles to take a Hall reading and the object will hardly move in that time. This kind of thing would require microprocessor control though, I doubt if you could do that "coil off then sample field then coil on at right strength and polarity" with op-amps alone, but maybe.
Quote from: Nink on December 01, 2014, 10:08:30 PM
They have to be using hall sensors or reed switches since they put it in a pillow etc so I agree Pirate88179 your probably looking at a circle of magnets with the ring magnet and hall hall sensor in in the corners with coil magnets making small adjustments to the voltage to ensure ring magnet is always locked. So maybe we need a broken microwave to salvage a large ring Magnet from and some computer cooling fans for hall switches.
Yes, I agree with you. Did you see it that video above that it can (according to the specs.) hover 9 pounds? Holy crap that is a lot of weight, and their hover height is very decent. I would be thrilled to hover 1 pound in a stable manner.
Bill
That has to mean that most of the levitation is done by the PMs and the coils modulate the field of the PMs. I think. That's the only way a small current (low heating) can possibly lift that much mass. I think.
TK:
Did you see that video? I am still dumbfounded!
For the price these folks are probably charging (and good for them as this is the best I have yet seen) it would not surprise me if there were an Arduino or Rasperry PI style micro processor in there somewhere. In quantities, I am sure they can be had very economically. Looking at the version they had hidden in a table, only the center part of the base (looked to be about 1.5" dia.) was showing through the wood. If that is true then the feedback sensors would all have to be in that small area right?
In the next day or so, I will see if I can find the patent (s) for this type of device. They probably have a patent in Europe as it looks like that is where they are from.
Bill
Quote from: TinselKoala on December 01, 2014, 11:03:12 PM
That has to mean that most of the levitation is done by the PMs and the coils modulate the field of the PMs. I think. That's the only way a small current (low heating) can possibly lift that much mass. I think.
But they can't reverse the polarity of the pm's that way can they?
Bill
Quote from: Pirate88179 on December 01, 2014, 11:07:02 PM
But they can't reverse the polarity of the pm's that way can they?
Bill
Well, do they have to? Say you have two oppositely oriented PMs, both being modulated in strength by their coils. You can weaken the N pole facing one and strengthen the S polar facing one...
Also the field from a big ring magnet can do funny things near the "hole in the donut".
http://www.youtube.com/watch?v=nUihboGkJnE
Quote from: TinselKoala on December 01, 2014, 11:10:28 PM
Well, do they have to? Say you have two oppositely oriented PMs, both being modulated in strength by their coils. You can weaken the N pole facing one and strengthen the S polar facing one...
Also the field from a big ring magnet can do funny things near the "hole in the donut".
http://www.youtube.com/watch?v=nUihboGkJnE (http://www.youtube.com/watch?v=nUihboGkJnE)
Could those mags be stacked then? If so, this might indeed be how the do it. Increase the north on one, increase the S on the other. If they are stacked with opposite poles facing each other (as they would really want to do on their own) then this would seem to work great! Like you said, the main lifting "power" is handled by the neos (If that is what is used) and hover is achieved and maintained by adjusting the coils like you said.
This is brilliant! Also, like you said, a lot less power input required=less heat...also brilliant! I just thought that base was large enough for a computer fan and that was how they did it.
I do believe that you have this device wired, as they say. Nice work. This never occurred to me at all.
Bill
PS I don't think you have to weaken the field on either of the mags, just boost the pole you need on the appropriate mag. at the right time. This way, since you are only boosting the S on the S facing mag, and vise versa, the mags will not get weaker over time...they might actually increase over time. So now, in this scenario, we are not talking about pole reversal, we are just talking about switching between magnets, which I believe your circuit will also do nicely.
I re watched the video and I think I was wrong it looks like they are using and optic sensor. You can see the hole in the botttom of the pillow and in the center of the table.
If (when) tk get a working (reverse engineered) model and puts a youtube video up, I would expect quite a few (hundred?, thousand??) views of that.
Full construction details also supplied of course. :)
Then wait for all the replication videos. :)
Since they are only tracking in the center I am not sure we would be accurate enough with a circle of infared receivers and an infared led in the middle and reflective tape on object. We may need an infared camera in the middle surrounded by infared LEDs in a circle with a small piece of reflective tape in the centre of the levitation unit. The levitation unit is a ring magnet with the centre covered and the small piece of reflective tape. See Johnny lee infared tracking with the wii remote. http://johnnylee.net/projects/wii/
Quote from: Nink on December 02, 2014, 07:39:25 AM
Since they are only tracking in the center I am not sure we would be accurate enough with a circle of infared receivers and an infared led in the middle and reflective tape on object. We may need an infared camera in the middle surrounded by infared LEDs in a circle with a small piece of reflective tape in the centre of the levitation unit. The levitation unit is a ring magnet with the centre covered and the small piece of reflective tape. See Johnny lee infared tracking with the wii remote. http://johnnylee.net/projects/wii/ (http://johnnylee.net/projects/wii/)
I think that the entire bottom of the floating magnet disk is mirrored. At least, it looked to me like it was in the video on their website. When they levitated the pillow, they just set the pillow on the magnetic disk...right?
I am still curious about the hidden version in the wooden desk top. Like I said...only a small dia. area is visible on the desktop. All of the sensors have to be in there...right?
Bill
PS. Allelectronics has hall sensors for like $.75 ea. For what that is worth.
I just placed an order for ten Allegro AH3503 ratiometric Hall effect sensors from China. Cost for the ten: one dollar and ninety-eight cents. Shipping: two dollars. So I'll have them here in my mailbox in 10 or 14 days, for a cost of about 40 cents each.
My local shop only has Hall switches for $4.99 each and they are just on off, they don't even sense magnet poll let alone provide voltage based on distance.
Here is how I think they are doing this with an Infrared LED in the middle of a circle of Phototransistors. The LED is slightly behind the Phototransitors so they can only see the reflected light when the reflected tape is directly above both the LED and the corresponding phototransistor The Phototransitor then completes the circuit activating the appropriate electromagnet. I am not sure if the electromagnets would need to go inside or outside of the magnetic ring, I guess that would depend on what is more effective, are we pushing or pulling, and what required the lowest amount of energy / heat to maintain a stable levitation.
Nink:
I think you are heading in the right direction there. I just wish I had one to rip apart, ha ha.
Will an electro mag. work using AC? (I can't remember if it will) Because, if so, then won't the poles swap polarity at whatever freq. the AC is?
Bill
PS I just looked it up and it will work. So, could we not simply adjust the ac freq. to get the balance we need to hover a given weight? Maybe use an air capacitor like in a radio? Of course, we still need the surrounding perm mags to keep it centered but, I think it might be possible to simply "tune" the air cap. to adjust the freq to keep the ring magnet hovering.
Just a thought.
With a lot of power you can levitate non-magnetic metals like copper or aluminum or brass with an AC electromagnet running at 50/60 Hz. The changing polarity of the field induces eddy currents in the metal piece and those eddys produce a magnetic field that opposes the field from the magnet (like polarities, switching very rapidly) so the metal plate rises up above the electromagnet pole pieces. John Hutchison did some of his fake videos like this.
It does take a bit of power though, and generates heat in both the electromagnet and the levitated metal. But no sensors or switching are needed, just the AC in the electromagnet. I used to demonstrate it with a "magnetic floor sweeper" we had at the lab, using a big variac for control and a chunk of aluminum plate for the levitated object. I don't have anything with the right pole pieces now, though.
I built a hall effect based levitator a few years ago and they are fairly simple however there are a few tricks. The first issue you will encounter is hysteresis or feedback causing oscillations, next high current draw due to coil saturation if the magnet is too close or high current draw if the magnet is too far away from the coils. The most efficient layout I found was using a coil above in attraction and a weaker permanent magnet below in repulsion. The most efficient layout does not actually levitate the magnet with a coil but uses a permanent magnet to produce the levitating force and a coil to stabilize the levitated magnet. I also used a neat trick I discovered to stabilize a rotating motor/magnet being levitated, a 1/2" aluminum plate below the magnet will dampen oscillations however it will not hinder rotation. Remember the magnetic field is stationary in space and bound to the source as such rotation on axis does not produce any noticeable eddy currents or dampening effects however any other movement on any axis will. ;)
AC
A few pics.
Maglev photo is a simple hall effect magnet levitation device and I was using a laser bounce system to map field inconsistencies.
The second photo is a magnetic bearing system I developed based on my magnet levitation experiments. Been sitting under the bench for a few years now but I was thinking of digging it out for the pulse motor build off. It works very well and is rock solid on all axis and by my estimate is a 99% passive system. Note on the far right outside column there is a silver aluminum disk in the column attached to the shaft, this is used to stabilize the shaft on all axis but does not dampen the axis of rotation as explained earlier.
The record for this bearing with only the 1" steel shaft spinning is continuous rotation for about 6 hours from 1000 RPM. By comparison a good set of ball bearings oiled with synthetic oil and the seals removed will spin approximately a minute or so. Interesting stuff and it becomes very apparent that a field is the ultimate bearing surface because it has literally no friction.
AC
I`d love to see any video you have of these devices.
@AC: in the second photo, one end of the shaft is bearing against an end plate somehow, is that correct? That is, there is one point of actual contact between the levitated shaft and the support structure?
@Lakes: at the risk of boring you silly....
Optically-sensed, Arduino controlled:
http://www.youtube.com/watch?v=xkiGTWODERo (http://www.youtube.com/watch?v=xkiGTWODERo)
Electrostatically rotated, passive permanent magnet levitated:
http://www.youtube.com/watch?v=tVfw-TeJ9r4 (http://www.youtube.com/watch?v=tVfw-TeJ9r4)
This could also be accomplished with concentric ring magnets, as I presume AC is using in his system, and which Steorn used some years ago in their "Plinth" Orbo demonstrations at the Docklands. Still will need one point of contact with the frame, though, but will work vertically (as Steorn) or horizontally as AC's demo.
I have a set of such ring magnets but don't have the ability at the moment to construct a frame with sufficient accuracy and strength to support them.
Yup, I seen that (suspension) video and also the point contact (usually a lead pencil against a mirror) type using ring magnets.
If this is the type used from the above pictures, they were not clear enough for me to tell.
I`ll have to watch the electrostatic one though, not sure if I've seen that one.
Much more interested in your attempts at a "no-contact" type of levitation, but I am beginning to see how it works with the circle of permanent magnets as stabilizers.
Once that is working :) the next step would be to inductively light some LEDs as well. :D
There is "no contact" in my coil-on-top maglev system and also no stabilizing magnet underneath. It's all done with optically-sensing the shadow of the bottom of the object and switching the coil on and off by the Arduino driving a power mosfet. The program in the Arduino corrects for ambient light by turning off the illuminating LED briefly every 100 pulses and sampling the ambient light falling on the photosensor, then correcting the pulse timing and strength so that the levitated object stays in the same position regardless of room lighting changes.
The system described by AC where the major lifting is done by PMs and then the coil just modulates that field, is a patented system that uses very little power, and also has the advantage of not dropping the object when the power goes off, instead the object jumps up and sticks to the PM lifting the weight. Sorry, I don't recall the inventor or patent number but it's available as a commercial display system as well. I think the electronic Levitron that is the subject here is also using that system, but inverted, acting in repulsion instead of attraction. Whether the field is sensed by Hall sensors, or the position sensed by optical means, is a question that is separate from how the levitation and stabilization is actually performed. Each sensing system has its advantages and disadvantages. I think a Hall effect sensing system will turn out to be more accurate and robust against outside perturbation, but also more difficult to implement in the actual build.
Still waiting for my Hall sensors from China, probably won't be here for another week at least.
Somebody (Lidmotor?) has demonstrated a top-coil levitation system that rotates the object and also lights up an LED inductively. I can't find the video at the moment, maybe someone else can. I did get an LED to glow a bit while being levitated in my system but not as well as Lidmotor (?) did in his.
The "coil on the bottom" system is more visually impressive, but of course more difficult to achieve.
I have seen a video where the "coil above system" is used to suspend a beer bottle and rotate it for an advertising display. :)
I will patently await the results of yours (and/or others) efforts for the "bottom coil" system. :)
@TK
I thought about patenting my magnetic bearing as I have never seen one like it however it would be better served in the public forum... so here it is.
Take two magnets in attraction and slip a 1mm plastic shim between them, mine are N42 150 lb pull strength ring magnets. Now try to pull them apart, we cannot it's too hard so we must slide them apart pushing on one and pulling on the other. I was doing this when I thought Hmm...shear force?, why not have four magnets with a shaft in between the two inner magnets and a frame holding the two outer magnets attracted to the two inner magnets apart.
Frame--NS NS--shaft--NS NS--Frame
Now imagine the left hand side magnets pull 150 lb to the left and the right hand magnets pull 150 lb to the right thus the shaft in the middle is in perfect magnetic balance pulling neither left nor right when perfectly centered with equal gaps on both sides. The frame must be strong and rigid because the frame magnets are pulling with a force of 300 lb+ inward just as the shaft magnets are also pulling with a proportional force outward. The adjustment bolts are to set the 1mm gaps between the end magnets in attraction and to adjust for the fact the boards keep warping under the strain, lol.
The neat part is that the attractive magnetic forces are axial however the load acts radially downward, the load is carried by the magnetic shear force on the magnetic field between the magnet pairs on each end . I use a 5mm ball bearing on one end to stabilize the gaps and the axial load on the 5mm bearing is measured in grams while the radial load peaks at around 40 Kg on the bearing shown. Which raised a question in my mind, the pull force between the two magnet pairs can have literally any value (tons)while the magnetic shear force carries the load however if both attractive forces sum perfectly to zero then the axial load would still be in grams thus it is easy to see why the system is 99% passive.
In a perfect world the magnet gaps on each end of the load bearing shaft would be perfectly equal and the axial forces would sum perfectly to zero thus the axial load on the stabilizing bearing(s) would be near zero and the magnetic shear forces would carry 100% of the load.
I believe the idea really clicked while reading A.D. Moore's book on electrostatics at the time. That is a cube of aluminum the size of a sugar cube in which all the charges have been separated by a distance of 1 m will have an attractive force of 32 million million million pounds... and yet all of these forces somehow sum to zero in this little cube of aluminum. If that does not boggle the mind then I submit nothing will, lol.
It's yours use it.
AC
I hate to burst your bubble, AC... but your system, if I am reading it right, is exactly the "Mendocino Motor" levitation system, also used by Steorn in the vertical plinth Orbos and also used by me in the video of the ES powered motor above. I don't think you'll be able to patent it...
Steorn used powerful ring magnets, two on the shaft and two in the frame, and a hard ball bearing against a micrometer head for axial support and adjustment. This allows vertical shafting or other orientations. The Mendocino Motor design appears in certain magnetic desk toys (without the motor part) and also in many YT video demonstrations of motors, usually solar-powered with magnets and coils in addition to the opposing support magnets (rings on shaft, other shapes possible on frame), but always with the single point contact restricting axial motion. The usual design, as I've shown in the ES motor, only works horizontally because gravity provides the stabilizing force up and down. Concentric ring magnets as Steorn used mean that the magnets themselves handle all stabilization at right angles to the shaft.
In CLaNZeR's replication of the Steorn Orbo plinth, you can clearly see how the ring magnets are arranged, to produce forces in opposition just as you have described. The rotor/shaft assy is pushed _up_ gently against the axial adjustment screw and all the weight is supported by the magnets in repulsion. And the strength of the forces and the precision required is why I can't at present duplicate this system, my necessary tools are not available to me (they are in Ontario and I'm in Texas). Although I do have a set of the correct magnets, donated to me some time ago by a Steorn replicator from another forum.
BTW congrats on reading Moore's book. Not too many people know about his work. I guess you've seen my Dirod and some of the demos I've done with it.
@TK
QuoteI hate to burst your bubble, AC... but your system, if I am reading it right, is exactly the "Mendocino Motor" levitation system, also used by Steorn in the vertical plinth Orbos and also used by me in the video of the ES powered motor above. I don't think you'll be able to patent it...
I figured someone might have patented something similar because it seemed like a good idea, I did a patent search but couldn't find anything. Although in a vertical orientation there is no actual shear force while on the horizontal axis there is. The shear force and the fact that any force could be balanced within itself is what inspired me. In any case it is known now so if someone can find some value in it then it's all good, it felt really good giving away my work even if it was patented by someone else. God I hope this isn't habitual or I'm really screwed, lol.
Edit... No my magnets are not arranged like that in the picture you posted, they are not one inside the other ie radial they are facing each other on each end on the axis of rotation. I made a pretty crappy picture below to show the layout, the load force is the shear force between the magnet faces acting downward. The magnet faces want to align with one another despite the fact the load is forcing it to move downward out of alignment. Think of a shear pin only the pin is a magnetic field.
Quote
BTW congrats on reading Moore's book. Not too many people know about his work. I guess you've seen my Dirod and some of the demos I've done with it.
I thought his book was awesome, it is one thing to understand something and quite another to explain it in terms anyone can understand. I have also built a small dirod, my variation of a charge doubler and a 24" Van de Graaff I need to brush some dust off of this week for my daughters science project. I just so happen to see the charge doubler up on a shelf collecting dust and will include a picture.
I imagine you have had your fair share of fun with leakage then?, it's kind of like herding cats.
AC
Quote from: TinselKoala on December 03, 2014, 11:53:43 PM
With a lot of power you can levitate non-magnetic metals like copper or aluminum or brass with an AC electromagnet running at 50/60 Hz. The changing polarity of the field induces eddy currents in the metal piece and those eddys produce a magnetic field that opposes the field from the magnet (like polarities, switching very rapidly) so the metal plate rises up above the electromagnet pole pieces. John Hutchison did some of his fake videos like this.
It does take a bit of power though, and generates heat in both the electromagnet and the levitated metal. But no sensors or switching are needed, just the AC in the electromagnet. I used to demonstrate it with a "magnetic floor sweeper" we had at the lab, using a big variac for control and a chunk of aluminum plate for the levitated object. I don't have anything with the right pole pieces now, though.
TK:
OK, now this is interesting to me. I understand the use of diamagnetic materials for the levitating disk, but, what if a real perm. mag were used? I feel like you would need to be able to adjust inputs to get it to hover but, in theory anyway, the AC is doing the work of a pole reversal circuit no? That is why I was thinking about being able to adjust the freq. to find the sweet spot balance point vs the weight of the hovering disk. This approach, of course, would not "adjust" to different weights of the hovering disk but, I am still thinking that, along with the perm. mags to keep the disk contained, it might still hover? Am I wrong in thinking this?
PS I have always wanted a variac, we used to have a very nice one in my machine shop. I can get a smaller one online for about $65.00. It is on my list of wanted stuff.
A.C.
Good to see you here again, I believe it has been a while.
Bill
Quote from: Pirate88179 on December 04, 2014, 10:17:53 PM
TK:
OK, now this is interesting to me. I understand the use of diamagnetic materials for the levitating disk, but, what if a real perm. mag were used? I feel like you would need to be able to adjust inputs to get it to hover but, in theory anyway, the AC is doing the work of a pole reversal circuit no? That is why I was thinking about being able to adjust the freq. to find the sweet spot balance point vs the weight of the hovering disk. This approach, of course, would not "adjust" to different weights of the hovering disk but, I am still thinking that, along with the perm. mags to keep the disk contained, it might still hover? Am I wrong in thinking this?
PS I have always wanted a variac, we used to have a very nice one in my machine shop. I can get a smaller one online for about $65.00. It is on my list of wanted stuff.
A.C.
Good to see you here again, I believe it has been a while.
Bill
No, I guess I didn't explain it very well. It isn't a case of diamagnetism, it's a case of induced currents producing a field that opposes the AC EM's field. It's an AC version of the classic demonstration of dropping a magnet down a copper pipe. The AC EM field is alternating; this changing field induces the eddy currents that circulate in the plate sitting on top of the pole pieces of the EM. These eddies are changing direction just as the EM field is changing polarity. The eddies have their own associated fields which oppose, that is, they act in repulsion, to the changing field from the AC EM. This produces a net force that tends to force the plate away from the pole pieces of the electromagnet. The levitation height is dependent only on the amount of power you can put into your AC electromagnet, so you can control the height with the Variac feeding the EM. No sensors, no frequency changing, just current, the more the merrier. It's still an unstable situation though, like balancing on a basketball; the levitated object will tend to move out of the sweet spot sideways if you let it.
Here, I found a video. Some people are calling this "diamagnetic" levitation, but it isn't an effect of a magnetic field being excluded, like the diamagnetic bismuth plate hovering over a permanent magnet. It is an eddycurrent effect, the induced eddys have their own magnetic field which acts in repulsion to the EM's field.
http://www.youtube.com/watch?v=1kUPibd9620
@AC: I like your little ES machine. And I'd love to see your big VDG in operation, I've built a few of them myself and I'm getting ready to make another small one. The only ES machine I have here is my big Bonetti machine, packed away in its crate, and yes... leakage is a problem, since the relative humidity here is almost always quite high. It's like 90 percent right now, no way I could get a static machine to work without drying the air. Damp air causes water to condense onto surfaces and that bleeds away the ES charge quickly and even prevents some machines from working at all, as you know. The rest of my static machines and demo devices are stuck up in Ontario-- where they work great, especially in winter!
I still think your mag-bearing design is going to turn out to be a variation of the ones I mentioned, I don't quite get the image you drew. It would seem to me that the shaft would snap to one side or the other and stick there, and I don't quite see how it doesn't droop down from gravity and rest on the "pins" sticking out axially from the shaft. I'd like to see some good photos of the apparatus if you have them, or even better a video showing the parts and their orientations. Certainly I could describe the operation of the Mendocino Motor system in the same words you used in the first description. If not... maybe you've found a counterexample to Earnshaw's Theorem, and that would be a big deal indeed!
ETA: Oh, I think I may be starting to "get it". Those pins are fixed to the frame magnets and are pressing gently on the ends of the shaft, right? So this keeps the shaft from snapping to one side. And it's the fringing fields from the "backside" of the magnets rather than the facing sides that keep the thing from drooping down. More like my "nikolayev trailer hitch" with the big ring magnet and the smaller cylinder magnet, locking into place. Maybe?
@TK
Quote@AC: I like your little ES machine. And I'd love to see your big VDG in operation, I've built a few of them myself and I'm getting ready to make another small one. The only ES machine I have here is my big Bonetti machine, packed away in its crate, and yes... leakage is a problem, since the relative humidity here is almost always quite high. It's like 90 percent right now, no way I could get a static machine to work without drying the air. Damp air causes water to condense onto surfaces and that bleeds away the ES charge quickly and even prevents some machines from working at all, as you know. The rest of my static machines and demo devices are stuck up in Ontario-- where they work great, especially in winter!
Oh the grief I have had with leakage, lol, one trick is to bake all PVC parts in the oven at low heat then coat them with a non-conductive clear coat. I also use a hair dryer on high heat to drive off residual moisture before start up. Leakage is like trying to carry water with a vegetable strainer but as you say in winter or before a thunder storm things really fire up.
QuoteETA: Oh, I think I may be starting to "get it". Those pins are fixed to the frame magnets and are pressing gently on the ends of the shaft, right? So this keeps the shaft from snapping to one side. And it's the fringing fields from the "backside" of the magnets rather than the facing sides that keep the thing from drooping down. More like my "nikolayev trailer hitch" with the big ring magnet and the smaller cylinder magnet, locking into place. Maybe?
Your almost there just reverse it, the stabilizing pin is on the rotating shaft end and runs through the hole in the ring magnets which is why ring magnets must be used in this design. The whole premise is based on a pretty simple effect. Stick a magnet to a bench then place another magnet over the first in attraction. The faces of the magnets in attraction will want to "align" perfectly with one another. Now try and "slide" the top magnet off, we can see there is a magnetic shear force which is preventing the top magnet from sliding away and this is the same force which carries the load overcoming the force of Gravity only I use a 1mm gap to reduce the sliding friction. I simply use a magnet pair on each end of the shaft to balance the forces and the force causing the magnet faces to align is the force which counteracts Gravity. I made a better picture below which should explain things, two floating pins can be used however I use one because it's easier. The pins are simply to hold a position of equilibrium between the two magnetic fields and any contrivance could be used to replace the pins.
QuoteI still think your mag-bearing design is going to turn out to be a variation of the ones I mentioned, I don't quite get the image you drew. It would seem to me that the shaft would snap to one side or the other and stick there, and I don't quite see how it doesn't droop down from gravity and rest on the "pins" sticking out axially from the shaft. I'd like to see some good photos of the apparatus if you have them, or even better a video showing the parts and their orientations. Certainly I could describe the operation of the Mendocino Motor system in the same words you used in the first description. If not... maybe you've found a counterexample to Earnshaw's Theorem, and that would be a big deal indeed!
Earnshaw's theorem holds so far as I know, believe me I have tested it in every way possible, lol. However it is an observation of a phenomena without any specific details as to how it may be applied practically. My magnetic bearing capitalizes on the effects of Earnshaw's theorem as follows. Earnshaw basically said a system of magnets will always be unstable because there is no point of balance in the system and the magnets will always move towards one another. However what he did not say was that "the closer the magnets are to a point of equilibrium the smaller the force to hold them in equilibrium" which is my premise. Thus any load be it 1 Kg, 100 Kg or 1000 Kg may be applied to the shaft however the force to hold the load in equilibrium between the magnet pairs will not change because it is perpendicular to the load. I should note that I have since found a way to hold the equilibrium position without any pins or mechanical devices... a work in progress.
I should also note the load shaft is "floating" and one would think it would move about however with strong magnets and small gaps it is rock solid. I mean I can literally grab the shaft and hold the machine up in the air and shake it and it feels like a solid shaft making the connection to the frame.
AC
I pm'd Lidmotor on Youtube to see if I could get him interested in the research going on over here. He was aware of TK's circuits and even replicated one of them already. I just wish I knew more and could actually help to move this forward. I will be experimenting soon for better or for worse.
I look forward to see where this topic goes from here.
Bill
@AC: Ok, I see it now! You have to carefully balance the distance so that the attraction on the left is a little stronger than the attraction on the right, otherwise it will snap over and stick on the RH side, right? An additional pin would be a good safety feature but it would normally only be very lightly loaded, less so than on the left side pin. I think.
Maybe this is something new. It definitely doesn't fit in the usual Mendocino Motor levitation system, and I've not seen it before, for sure. It's too bad you've disclosed it here otherwise it might actually be patentable. I can see it could be very useful in many applications.
The ring magnets I have on hand for the Steorn rep are radially polarized, I only have one big ring magnet that is polled axially, so I can't play around with your system... yet. Maybe I can get hold of some proper ring magnets later on.
Thanks for taking the time to explain it to me. I can be just as dense as the next fellow but I do try to work things out, and if you keep at it I usually will finally get the point.
;)
Quote from: Pirate88179 on December 06, 2014, 01:20:39 AM
I pm'd Lidmotor on Youtube to see if I could get him interested in the research going on over here. He was aware of TK's circuits and even replicated one of them already. I just wish I knew more and could actually help to move this forward. I will be experimenting soon for better or for worse.
I look forward to see where this topic goes from here.
Bill
Lidmotor is way in advance of us poor tinkerers over here, he is the King of pulse motors. I envy his fine designs and his excellent results. He would just be bored stiff, in between bouts of hysterical laughter, looking in here.
:-[
@TK
Quote@AC: Ok, I see it now! You have to carefully balance the distance so that the
attraction on the left is a little stronger than the attraction on the right,
otherwise it will snap over and stick on the RH side, right? An additional pin
would be a good safety feature but it would normally only be very lightly
loaded, less so than on the left side pin. I think.
Now you have it, if you look at the picture you will see I have two sets of vertical boards. The inside one's are for safety and to keep the shaft from slamming to the right or left while the outside boards hold the outer magnet sets. To be honest I was very surprised how small the force was to hold the shaft in place and the end cap to hold the bearing can be adjusted so the force is down to grams.
QuoteMaybe this is something new. It definitely doesn't fit in the usual Mendocino
Motor levitation system, and I've not seen it before, for sure. It's too bad
you've disclosed it here otherwise it might actually be patentable. I can see it
could be very useful in many applications.
The ring magnets I have on hand
for the Steorn rep are radially polarized, I only have one big ring magnet that
is polled axially, so I can't play around with your system... yet. Maybe I can
get hold of some proper ring magnets later on.
I'm really not interested in patents and believe a technology not used is a useless technology so it makes sense to me that I should give it away rather than have it sit around collecting dust... if you only knew what I had under my bench collecting dust, lol.
AC
Quoteif you only knew what I had under my bench collecting dust, lol.
We'r listening, it does feel good to give thats a human condition that enhances the soul.
Thank You for the magnetic bearing.
https://www.youtube.com/watch?v=7740EhgwfII (https://www.youtube.com/watch?v=7740EhgwfII)
I'm suspecting hoax anyway.
Quote from: Qwert on December 06, 2014, 03:44:44 PM
https://www.youtube.com/watch?v=7740EhgwfII (https://www.youtube.com/watch?v=7740EhgwfII)
I'm suspecting hoax anyway.
Not a hoax, the apparatus operates as shown, it does produce rotation in the center magnet spinner.
However the "explanation" is totally bogus and there is no "magnetic vortex" produced by this, or any other arrangement of permanent magnets. The rotation motion is powered by Mister Hand, and it's easy to prove this. You will never see such an apparatus working where the outer ring is rigidly mounted so that it cannot move. If there were such a "magnetic vortex" the rigid mounting would not affect the result. Mister Hand is a critical component of the complete apparatus and it will not rotate without his assistance.
The difference between the "center of repulsion" caused by the outer ring of magnets, and the point of contact of the center spinner with the substrate, creates a torque couple which results in the spinning of the spinner. To maintain this couple the outer ring needs to be moved, slightly but continuously. The presenter is fooling himself by thinking he is not applying any work to the system, and the reason he is able to fool himself is because he is _theory-driven_, and will always seek to explain observed phenomena in light of his dearly-held theory, rather than using observations to test his theoretical hypotheses by doing proper, true experiments.
Ask him why the device does not spin when the outer ring is rigidly mounted, and you will get in return some more gobbledegook "explanations" that still attempt to salvage the bogus theory, rather than a factual and true interpretation of what the observation indicates: No magnetic vortex exists and the spinning is due to some other cause, namely the continuous movement of the outer ring, caused by Mister Hand.
The famous "Minato Motor" is another case of this phenomenon. The Minato Motor consists of a simple, non-powered rotor with all magnets facing the same polarity outwards around the periphery of the rotor. You hold a stack of magnets in your hand, and approach the rotor with the stack at various angles. Eventually you find an angle and distance which gives constant rotation of the rotor. But when you try rigidly mounting the hand-held stack in the "exact same" position and angle... it doesn't work. Since you "know" that your theory is correct, you waste hours, days and weeks of your life trying to get it to work without the hand-holding part... when in actuality, an _observation-based_ approach to performing True Experiments will very quickly reveal that you are in fact "pumping" the system with slight motions of your hand, actually caused by trying as hard as you can to hold the stack still, but since the passing rotor magnets are pulling/pushing, your little out-of-phase motions are actually providing the input power to rotate the rotor.
As Richard Feynman said, the easiest person to fool is yourself.
Quote from: TinselKoala on December 06, 2014, 05:34:16 AM
Lidmotor is way in advance of us poor tinkerers over here, he is the King of pulse motors. I envy his fine designs and his excellent results. He would just be bored stiff, in between bouts of hysterical laughter, looking in here.
:-[
Funny you should mention that. I heard back from Rusty (Lidmotor) and he said he has now read this entire topic. He said that years ago he tried building a Levitron using hall sensors and an op-amp but could not get it to work. He said that later, he built an infrared device that worked quite well. He said he will be following us here to see what is going on. He did mention that TK should be able to build this new type of Levitron if he has enough time.
So, there you have it TK, a vote of confidence from Lidmotor. I, for one, can not wait until your hall sensors show up.
Bill
PS No pressure.
Thanks, TinselKoala. This site becomes very helpful thanks to some dedicated guys including you. Keep doing this, please.
@Dave45
QuoteWe'r listening, it does feel good to give thats a human condition that enhances the soul.Thank You for the magnetic bearing.
Like many here I have the usual assortment of unworkable devices and as TK mentioned ... the easiest person to fool is ourself. However even an old dog can learn new tricks and sometimes an original thought and sheer luck may converge.
I noticed a couple of unfinished projects collecting dust which have an interesting premise. One is that I found a way to vary an off the shelf capacitor (capacitance) from min to max value on the fly which I thought impossible prior to actually build one. Another is a self-synching grid tie inverter which does not use boost conversion or transformer action to raise the source voltage. Nor does it use an "H" bridge on the output section which raises all kinds of questions doesn't it?. I'm not quite ready to disclose these yet and simply mentioned them so that people might consider the premise and how such devices might work. It's all left field outside the box kind of stuff which I enjoy working on.
I understand many things seem impossible however the seemingly impossible is actually a pretty straight forward process. I use a thought process related to Critical Thinking (observation and analysis of our thinking concerning the observation) and Looping (observe, deconstruct, change/reverse premise and process, repeat). It works and multiple loops are formed at which point the dots are connected to form other loops and at some point solutions.
AC
Found this on YouTube http://youtu.be/vypjmqq9i-o
Thoughts ?
Quote from: Nink on December 10, 2014, 09:37:19 PM
Found this on YouTube http://youtu.be/vypjmqq9i-o (http://youtu.be/vypjmqq9i-o)
Thoughts ?
Wow! Nice find. I translated his description and all it said was " home made levitron."
I tried translating a few of his comments answers and did not get very much at all.
It looks like he has re purposed some other type of device and hacked it into this device. At first, I thought it was a hard drive...but now I am not sure.
I see he has the leds for feedback and it does hover very well.
Maybe someone on here that speaks Russian can contact him and get more details?
Thank you for posting this.
Bill
Link to translated webpage
https://translate.google.com/translate?sl=auto&tl=en&js=y&prev=_t&hl=en&ie=UTF-8&u=http%3A%2F%2Fmozgochiny.ru%2Felectronics-2%2Fsamodelnyiy-levitron%2F&edit-text=&act=url
Interesting. It looks like a floppy drive enclosure of some kind but I've never seen one with a big heatsink on it like that. It certainly acts like the commercial version. I was surprised to see no disturbance when he passed the rod beneath the object, interfering with the light from the LEDs, so I'm wondering about the LEDs still. Are they part of the sensing loop, or just for show? I dunno.
I've put that project on the "back burner" for now since my Hall sensors still haven't arrived from China. Should be a few more days, not too many I hope.
From the translated web site linked above, he's using hall effect sensors and a differential amp.
The LEDs are just for show.
Lakes:
Thank you so much for posting the translation page. So, hall sensors appear to be the ticket here as well then.
TK:
At first, i thought it was a hard drive package but then, as you say, it could also be some other type of drive unit. The heat sink confused me as well but, I suppose that could easily have been added to the drive enclosure. The fact that he is using a heat sink is probably good news as I doubt the Levitrons are using one...or at least not a large enough one as there seems to be some problems with longevity with those.
Bill
The Forum that discuses this is an interesting read but googles translation engine is painful at best.
https://translate.googleusercontent.com/translate_c?act=url&depth=1&hl=en&ie=UTF8&prev=_t&rurl=translate.google.com&sl=auto&tl=en&u=http://radiokot.ru/forum/viewtopic.php%3Ff%3D3%26t%3D4810%26hilit%3D%25D0%25BB%25D0%25B5%25D0%25B2%25D0%25B8%25D1%2582%25D1%2580%25D0%25BE%25D0%25BD&usg=ALkJrhibx4UoU0UwyDScPJvF8d6PBk0TtQ
there are some great videos of this in the thread.
https://www.youtube.com/watch?v=rQbGKWUjlBg
https://www.youtube.com/watch?v=FZKuk6ay6Pc
https://www.youtube.com/watch?v=S3ANCG_Tbjc
https://www.youtube.com/watch?v=FMCir6MNYzk
Nink:
Those videos are great!!!!! I think it was the 3rd video where it showed like 5 small wound electro mags on the bottom. It is great to see that all of these variations appear to work very well. I will look at their youtube accounts to see if there are any vids with schematics or how to build.
Man, I feel like we are really late to the party here. I thought this would be a cutting edge project, but now we see this is not the case, ha ha.
Great find and thank you for posting.
Bill
Here is another video from the first video guy posted above:
https://www.youtube.com/watch?v=NyzgB7Ah3IM&list=UUhRJmfON7S6q-TaiUnarWXg (https://www.youtube.com/watch?v=NyzgB7Ah3IM&list=UUhRJmfON7S6q-TaiUnarWXg)
This thing is beautiful!! Evidently, this video was done prior to the other one we have seen.
That might be the coolest device I have seen yet. I want one of these floating in my living room.
Bill
PS Holy crap! Here is another video from yet another guy:https://www.youtube.com/watch?v=eexeEg2N7kw (https://www.youtube.com/watch?v=eexeEg2N7kw)
https://www.youtube.com/watch?v=tPpgz0bpDrY&list=UUW1ksApUmz61fqfVRgdYfaw (https://www.youtube.com/watch?v=tPpgz0bpDrY&list=UUW1ksApUmz61fqfVRgdYfaw)
Check this guys channel on Youtube. He has like 10 videos on his devices showing his experiments and progession.
Bill
https://www.youtube.com/watch?v=BC0AZWXk224 (https://www.youtube.com/watch?v=BC0AZWXk224)
Another type built by some UBC physics students it appears.
Bill
http://www.google.com/patents/US7348691#v=onepage&q&f=false (http://www.google.com/patents/US7348691#v=onepage&q&f=false)
Above is the patent that they ref.
https://www.youtube.com/watch?v=RDvH76Cj-UY (https://www.youtube.com/watch?v=RDvH76Cj-UY)
MIT open courseware showing how to levitate a coil of aluminum wire 3" over an aluminum plate using Lentz's law. This appears to use a lot of power though.
Bill
Quote from: Pirate88179 on December 11, 2014, 10:55:29 PM
https://www.youtube.com/watch?v=RDvH76Cj-UY (https://www.youtube.com/watch?v=RDvH76Cj-UY)
MIT open courseware showing how to levitate a coil of aluminum wire 3" over an aluminum plate using Lentz's law. This appears to use a lot of power though.
Bill
Put 110v into a coil and place over joining corners of 4 aluminium plates
https://www.youtube.com/watch?feature=player_detailpage&v=azsqhKg8hX8#t=254
Similiar to 4 corners of diamagnetic pyrolytic graphite and 4 neo magnets
https://www.youtube.com/watch?v=yFX_O8Q8qto
The induction current type levitating an aluminum plate uses a lot of power and things can get really hot quickly!
https://www.youtube.com/watch?v=txmKr69jGBk
Which is why I much prefer this hall effect/magnet system which uses less power.
Btw, the "Levitator Prototype 1 "rotating crystal display was awesome!
This system using an arduino and a H Bridge is (I would guess) probably the one that Tk will be using.
https://www.youtube.com/watch?v=qS1cdUzFX8M
I like this one, from the same maker as the Arduino one above, but not using Arduino I think:
http://www.youtube.com/watch?v=JQypYoDSFrA
The sphere magnet doesn't want to flip over!
Quote from: Pirate88179 on December 11, 2014, 10:37:29 PM
https://www.youtube.com/watch?v=tPpgz0bpDrY&list=UUW1ksApUmz61fqfVRgdYfaw (https://www.youtube.com/watch?v=tPpgz0bpDrY&list=UUW1ksApUmz61fqfVRgdYfaw)
Check this guys channel on Youtube. He has like 10 videos on his devices showing his experiments and progession.
Bill
Yep, he's the one who did the sphere levitator. Good find!
@TK
QuoteI like this one, from the same maker as the Arduino one above, but not using Arduino I think:http://www.youtube.com/watch?v=JQypYoDSFrA (http://www.youtube.com/watch?v=JQypYoDSFrA)The sphere magnet doesn't want to flip over!
That is cool and it looks like he is using four coils as far as I can see. Note the oscillations, I noted similar effects when levitating a 1" dia x 1/2" N42 Neo. I believe drag falls by the V^3 rule and a small flick would cause my levitated magnet to oscillate for hours. It kept oscillating so long I got bored and just turned the damn thing off.
That setup is a bit of a catch 22, if he is only using coils then at that distance the power draw would be large and if he uses a PM in the center then he would saturate his coils again increasing the power draw. It's a vicious circle although an Arduino and PID loop would easily solve the oscillation/hysteresis issues. It would also be fairly easy to apply a MPPT algorithm, not max power point tracking but minimum power point tracking if a central PM in repulsion were used.
AC
TK and All:
OK, I have a weekend and some time. I also have a salvaged roll of zip cord and, an 8" toroid from a huge transformer.
What would happen if I wound this toroid with the zip cord, bifilar so I don't have to separate the cord, and used a light bulb for a load, because if I shorted it my breaker would blow....and then, took a disk magnet and attempted to hover it above this toroid?
What would happen? I realize that it would not be self-correcting as there are no hall sensors involved, but, would not the polarity of this toroid be reversing at 60 times/sec? Is there a sweet spot distance/perfect weight that might hover with this cheap and dirty set up? I have over 100 1/4 inch neos here that I could stick to a disk and vary the repulsion of the hovering disk if needed.
My question is...if there is 0 chance of this ever working, I will work on something else this weekend. If there is a small chance that this "might" work, then I will give it a go.
I also have about 40 hard drive magnets I can use to keep the hovering disk from sliding off if needed also.
My other projects are on hold at the moment, and I am looking for something interesting to do.
What do you think?
Thanks,
Bill
PS I realize that the hovering crystals video was due mainly to the visual effects of the crystals with simple leds showing through them, but, I think that the combination of hovering and the crystals, and the leds was simply brilliant. Maybe I am easy to please but it was cool.
PPS I was also just thinking that I could vary the amp draw by using different wattage light bulbs as well. A 100 or a 150 bulb would draw a lot of amps through the toroid. Of course, maybe this is a fool's errand.
http://rfhv.com/ (http://rfhv.com/)
This student has several levitators on this page. (scroll down to see them)
He has one design that uses no hall sensors. This kid really builds some nice stuff. Here is a photo of one of them.
Bill
https://www.youtube.com/watch?v=8gko4Oadn3g#t=86 (https://www.youtube.com/watch?v=8gko4Oadn3g#t=86)
A very creative use of the levitators.... a back to the future desk top hover board!
Bill
Very nice indeed!
I've still got a long way to go, and I can tell that my finished project (if I ever do finish) is sure not going to look as nice as those do. :'(
But my Hall sensor order arrived this afternoon and I put together a little testing and demonstration circuit:
http://www.youtube.com/watch?v=1GazsfQLu38
TK:
Nice video! Thank you for making it very clear how the hall sensors work. I really like your circuit as it has many other uses besides repulsive magnetic levitation.
I began fooling around with the non-electronic old school style Levitron (spinning magnet top hovering over speaker magnets) and found out that there is a very narrow window of weight and height that this thing will work in. No hovering here yet, but getting close. Very interesting effects when over the hole in the center of the large magnets.
Bill
Well, I think I figured out that that guy with the beautiful hovering crystals device was simply using this commercially available
device from a hovering globe display
http://www.amazon.com/Fascinations-Levitron-Globe-World-Stage/dp/B002W8IH4Y/ref=sr_1_4?ie=UTF8&qid=1418577848&sr=8-4&keywords=floating+globes (http://www.amazon.com/Fascinations-Levitron-Globe-World-Stage/dp/B002W8IH4Y/ref=sr_1_4?ie=UTF8&qid=1418577848&sr=8-4&keywords=floating+globes)
It appears that he removed the magnetic disk from the globe (which it says you can do to hover your own items) and placed a piece of plexi over the base and then added the crystals. It is still a nice effect, just not totally home made as I first thought.
I am really tempted to try to sell some stuff and purchase this device to play with. Of course, I will take it apart, ha ha. This is the lowest price I have found so far......I will think about it.
Bill
PS
http://www.amazon.com/Huhushop-TM-Levitron-Revolution-Technology/dp/B00HAW8S6O/ref=pd_sim_t_3?ie=UTF8&refRID=080VKG6J8TDPAJGMSVDT (http://www.amazon.com/Huhushop-TM-Levitron-Revolution-Technology/dp/B00HAW8S6O/ref=pd_sim_t_3?ie=UTF8&refRID=080VKG6J8TDPAJGMSVDT)
Here is one without the globe (who cares?) for $52.00. This is now the cheapest one thus far.
I wonder if he/it can levitate some of the sh!t he spreads here, or maybe some that he licks from the kings rim ?
Serious replies only.
Regards...
Edited for troll approval...
Quote from: Cap-Z-ro on December 14, 2014, 04:38:35 PM
I wonder if can levitate some of the sh!t he spreads here, or maybe some that he licks from the kings rim ?
Serious replies only.
Regards...
This post speaks for itself. I am only quoting it to preserve it so when it is edited, we can all see what was originally posted. I suppose it would be nice if he at least used complete sentences but, oh well.
Bill
Those who can, do, Bill. Those who cannot do, just insult those who can. You know that. Let the pottymouth adolescent spew his garbage, it matters not one whit to people who actually build things that work, like you or me.
Hall effect sensor demo 2: improved stability, great sensitivity.
http://www.youtube.com/watch?v=Wl8Ke62r468
Boy, trolls sure get irritated when you troll them back.
Guess a dose of their own medicine isn't to their liking.
Cap happens to hold Patents in Canada and the US...with all artwork and specs done by his truly it shood be noted.
i rather doubt these 2 bozos have ever had an original thought.
Regards...
Cheapest on ebay £40
http://www.ebay.co.uk/itm/Novel-Decor-Levitron-Ion-6-Magnetic-Rotating-Globes-Floating-Levitating-Earth-/390973640000?pt=UK_Home_HomeDecor_Miscellaneous&var=&hash=item5b07d84d40