To ACTIVE STABILIZATION & COMPASS
Positionning using optical sensor. (reflection & lateral reading).
|Embase test jig,
Positionning using hall sensors. (lateral reading).
|More complicated for the FLYINGMAGNET© concept||More performing for the FLYINGMAGNET© concept
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|Test jig in geometry #0
Obviously, the criteria defined in the following page are not respected.
|The sphère (full of water): D=68 mm, V=165 cm³
emerged weigth: approximately 170 g
apparent maximum weight in the chosed working range:
approximately 70 g
The sphere: full of water (weight zero when fully immerged) is located under the object in suspension.
The curve of variation of weight of the sphere in function of the height of emerged part, takes advantage on the curve of the attraction force in function of the distance between the magnets.
Vice versa: an empty sphere, equipped with a magnet (geo #5, page "tech") can be anchored stably above a magnetic mass without material link. This is perhaps not a good idea to try that in an aquarium, the fishs may lose the North.
The neodymium magnets:
sphere: 25,4 mm (1"), disc: 25,4 mm x 6,35 mm (1" x 1/4"). The adjustment at the middle of the operating range is done by sliding the main tube and the support of the magnet.
Distance between magnets: approximately 55 mm (2")
The stable position shown, allows a vertical swing of a magnitude more than 2 cm (3/4") without losing control (falling of the magnet or stick to the ceiling), the damping is perfect!
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|Two are better than one !
Sphere neodymium, diam: 19 mm (1/2") and a fragment of neodymium epoxy coated, spaced by approximately 50 mm (2").
|The two spheres are suspended and linked magnetically. Moving one moves the other, removing one makes the other fall. The spherical form is absolutely not obligatory.|
|Determining the poles of a magnet :|
The pole of a rotating free magnet that orients towards the geographical North pole, is defined as the North pole of this magnet, and consequently the North pole is the one that will attract the south tip of a compass's needle.
Note : This test must be carried out at a good distance from the magnet in order to avoid the reversal of the compass's poles!
How the compass is made:
Hollow Sphere in soft iron (fancy chocolate box...), suspended magnetically and two spherical magnets of 12.5 mm, poles in series at 180 °, positioned on the equator.
The Stability control uses 2 field coils (Top & bottom), one disc magnet 25x5mm inside the sphere at the top, one disc magnet 10x5mm at bottom outside of the sphere and two disc 100x5mm magnets stacked at the top of the core of the main coil (all magnets "neodyme").
The controller is the same as the one used in the other demos.
Compass oscillating around the north after being disturbed :
Video 270 Ko AVI - (wmv9) : click on picture