maglev trains

[TheBigDog]

Sounds like a linear motor. As the train moves down the track it pushes and pulls on magnets located along the track. The "people movers" at Disney World's Future World have been using this for 40 years, although they are wheeled, not maglev. I think you are on the right track. Space out the magnets under the train. As the train passes over them you need to flip the polarity of either the magnets on the train or the track in precise time so that they push and pull the train along.

Good luck!

Bill

[CraigD]

Please correct me if I’m wrong, but I gather you’ve made something that looks, in cross section, like the attached thumbnail (were the black is foamboard, the red is magnet strip, and I may have the magnets poles backwards, but not to worry) and levitates OK.

Congratulations! That’s more than I’ve done.

The magnet and pulley scheme you describe seems possible, but not much like a real maglev. Instead, I think this might work better:

Make several electomagnets by wrapping insulated wire around a large nail, secure with tape of glue, leaving plenty of extra wire.

Stick them through the bottom of the track foamboard, with both ends of the wire coming out the bottom. For starters, space them as widely as the train car (you may want to try different spacing later)

To move the train, connect the wire ends of one electromagnet to a battery so that it attracts the train. Then disconnect that electromagnet, and connect to the next one, and so on. If you reverse the wires (the polarity) of the previous magnet, you can cause it to repel the train, moving it more quickly.

The polarity (N/S vs. +/-) of an electromagnet is given by the right hand rule, but you don’t really need to know it – just try it one way, and if that repels the train rather than attracting it, just reverse the wires. There are formulas for calculating the number of windings around the nail and the voltage of the battery to produce a given magnetic field strength, but again, it isn’t necessary – just follow the “bigger is better” rule, wrapping the nail as many times with the thinnest insulated wire you can find (there is a special kind of wire for this, with a very thin insulator, but any thin, low-current wire should work), and using the biggest practical battery (a 9-volt is will give you the same voltage as 6 1.5 AAs in a row, and not require a holder)

If this works, you should be able to put it all together with whatever switches you have on hand, to make operating it by hand smoother and prettier, or, if you’re really clever, something that will handle the switching automatically.

This sounds like fun. It may take a good bit of tinkering to get to work. I wish I could lend an actual hand, but the internet’s not quite ready for that .

[InfiniteNow]

So shadow,

Do you still have any questions? If so, you should ask them here, in reply to this thread, so all of our members can assist and clarify.

[shadow67]

yeah
just want to tell you that the conveyor belt idea is great the only problem is can somebody give me an idea on how to make a simple conveyor belt

[CraigD]

Originally Posted by PM from shadow67

… our instructor told us that everything should be working on its own not manually except for switches or remote control.

The scheme I described would, I think, qualify as “not manual except for switches”. However, if you’d like to try something simpler, I’d suggest just attaching a small battery powered motor with a model airplane propeller. Switched on, it should “fly” the train car from one end of the track to the other pretty well.

The easiest way I can think of doing the above is to find a cheap battery powered toy plane (eg: an Airhogs Echarger, take off the wings and pretty decals, and mount it with a bit of foamboard and hotglue.

The Inductrack inventors have proposed driving full-size maglevs with propellers or turbojets, so this really isn’t a far-out solution.

If you’re committed to the conveyer belt solution, I’d consider using bended coat-hanger wire for one end, possible with a plastic or wood thread spool, the drive axle of an electric motor on the other, possible with a single wrapping of duct tape to give it better traction, and some elastic cord, which you can get at any sewing store. If you get the tension right, it should work. An easier solution would be to glue or tape the end of some heavy thread or light string to the motor axle, the other to the train car - a winch, not a conveyer belt.

[shadow67]

can somebody tell me how do i tell which side of the electromagnet is north and which side is south?

[InfiniteNow]

Grab another magnet that's marked. Hold the North end upward, and put the other magnet near the north end. If it attracts, then the end of the "other" magnet is south. If it repels, then it's north.

You can also get a compass (you know, the thing that helps you navigate north south east west, and really used by sailors for centuries.) Hold the compass with north facing forward, then bring your magnet near it (edge on). If the needle of the compass is repelled, then you have the north end of your magnet by it. If the needle of the compass comes toward your magnet, then you have the south end of the magnet by it.

[shadow67]

ye thanks

[CraigD]

Originally Posted by shadow67

can somebody tell me how do i tell which side of the electromagnet is north and which side is south?

Originally Posted by InfiniteNow

Grab another magnet that's marked. Hold the North end upward, and put the other magnet near the north end. If it attracts, then the end of the "other" magnet is south. If it repels, then it's north.

You can also get a compass…

And, of course, if you want to change an electromagnet’s polarity (swap its N and S poles), just reverse its current (swap the battery terminals the wires are connected to).

If you want to calculate the electromagnet’s polarity using theory, use the “right hand rule”: if you have wrapped wire around a nail in a counter-clockwise direction (looking downward) from top to bottom, and you attach the top wire to the negative terminal of the battery, the bottom to the positive (electric current flows from negative to the positive), wrap the fingers of your right hand in the direction of the current flow, and note the direction your thumb is pointing – up. The N pole of the electromagnet is its top, pointing up.

[shadow67]

i just wanted to know in a little detail if someone can explain me how to position those electromagnets along the track with its wires. and how many switches will be required for turning on and off the magnetic field? my track is 20" in width and 40" in length.