Model Maglev Train containg Hall Sensors on the train... Best Method?

[David Garza]

Hello,

I am very new to this, and am pressed for time. A friend and I are
looking to build a model maglev train that will be able to hover
independently from any sides or rubbing against anything visible.

From the BEST I can understand is:

1. We would use a hall sensor to judge the distance from the car to the
track; this will be used to maintain a horizontal balance so it will
not touch the sides. The Hall sensors would be mounted on the train.
2. We would use static magnets (ferrite bar magnets) to maintain a
constant height. However, I have read this may interrupt the horizontal
balance provided by the Hall sensors.

Now, another idea which I am leaning towards is:

A 'v' shaped track, as such:


\ /\1 1/\ /
\/ / \ \/
\/ \/
\ /
\ /
-------------------

This would allow us to remove the static ferrite bar magnets on the
bottom. But that means the Hall sensors would have to be mounted on the
track, where electromagnets would be mounted, because the track will be
maintaining vertical and horizontal stability.

The Hall sensors would replace where the #1's are and the
electromagnets would be right beneath the Hall sensor that is
controlling it.

Here are my questions:

1) What type of and how should the magnets be setup on the cart itself?
2) How many Hall sensors would we need and how far apart should they be
spaced?
3) What should we do concerning propulsion, as we want to regulate the
speed ourselves (if possible)?
4) I read that the feedback loop of the Hall sensors would eventually
move the cart so much that it would eventually come off of the track;
what can we do to prevent this?

Thank You all for your help!

Thanks and God Bless!

David Garza

 

[Richard the Dreaded Libertarian]

Hello,

I am very new to this, and am pressed for time. A friend and I are
looking to build a model maglev train that will be able to hover
independently from any sides or rubbing against anything visible.

Hah! Good Luck!
http://www.google.com/search?q=maglev&btnG=Google+Search

Cheers!
Rich

 

[Paul Hovnanian P.E.]

Hello,

I am very new to this, and am pressed for time. A friend and I are
looking to build a model maglev train that will be able to hover
independently from any sides or rubbing against anything visible.


1. We would use a hall sensor to judge the distance from the car to the
track; this will be used to maintain a horizontal balance so it will
not touch the sides. The Hall sensors would be mounted on the train.
2. We would use static magnets (ferrite bar magnets) to maintain a
constant height. However, I have read this may interrupt the horizontal
balance provided by the Hall sensors.

Now, another idea which I am leaning towards is:

A 'v' shaped track, as such:

\ /\1 1/\ /
\/ / \ \/
\/ \/
\ /
\ /
-------------------

This would allow us to remove the static ferrite bar magnets on the
bottom. But that means the Hall sensors would have to be mounted on the
track, where electromagnets would be mounted, because the track will be
maintaining vertical and horizontal stability.

The Hall sensors would replace where the #1's are and the
electromagnets would be right beneath the Hall sensor that is
controlling it.

Here are my questions:

1) What type of and how should the magnets be setup on the cart itself?
2) How many Hall sensors would we need and how far apart should they be
spaced?
3) What should we do concerning propulsion, as we want to regulate the
speed ourselves (if possible)?
4) I read that the feedback loop of the Hall sensors would eventually
move the cart so much that it would eventually come off of the track;
what can we do to prevent this?

Thank You all for your help!

Thanks and God Bless!

David Garza

Why not use the same scheme that full sized Maglevs use?

I belive that their levitation and track centering schemes are based on
magnetic repulsion. This provides its own negative feedback with no
control electronics. If
the car moves too far in one direction, the repulsion on that side
increases and provides a force that moves the car in the opposite
direction.

Some systems use permanent magnets in both car and track, which provide
levitation at all times. Others use magnets in the car and conducting
loops in the track in a form of linear induction motor. These ill only
levitate when the car is moving, so the car will need wheels on which to
'land' when the car stops.