Images geometry #5 & #6 - hall mode

No, this is not the curvature of the earth.
This geometry contrary to the precedent, permits the object in levitation to rotate freely 360 around its vertical axis. If the object is made rotating, it will keep its momentum a very long time...
Ceramic magnet 19 mm x 10 mm th. or
neodymium 25 mm x 5 mm th. (fly over the picture)
Ceramic magnet (grade 5)
Sizes: 19 mm - th.10 mm

Spherical composed objects in levitation: ( 65 mm or 82 mm - weight: > 50 g), the poles plane of levitated magnet have the tendency to stay parallel to the poles plane of sustentation magnets and this property is reinforced by the control of the position for witch the stability is amazing. The coupling with the coils fields becomes rapidly insufficient for a levitation elevation above 20 mm, on this test jig the practical limit of levitation is about 25 mm.
A toy normaly suspended: (fly over the picture)
 25 mm, neodymium magnet in levitation Video: 80 Ko - 10 s duration
(.AVI - wmv9).

(click on the picture)

 video: 19 mm ceramic magnet in levitation

 Globe ODYSSEY 82 mm in levitation
Note: In the geometry #5, the elements are positioned very differently compared to the precedent geometries, the elevation and trim of the levitating object are self-stability by principle, the active stabilization is applied only to the vertical axis. (4 or 6 field coils, 2 or 3 channels controller and 6 magnets sets for sustentation) Note: A weak oscillation around the vertical axis remains during the video, showing the freedom of an object in levitation, this oscillation is the indication that a direction has been slightly privileged by the adjusments. Note: In this demo, 6 coils fields, 3 channels servo controller and 6x2 sustentation magnets are used. One coil for elevation control is inserted at the centre for the weight compensation of different objects (not connected here).

Geometry #5 (cont.)

Other objects composed and levitation of a neodymium magnet with its horizontal axis

Dodecahedron on base in horizontal position.
weight: 50 grams, material: aluminium, neodymium magnet: 25 x 5 mm

test jig for geometry #5 in vertical position like used in
demos at the right hand. (fly over the picture)
Neodymium magnet 25x5 mm
its magnetization axis is now horizontal.

The magnet is separated from the test jig by an aluminium sheet.
(fly over the picture)
 Embase for geometry #5 in vertical position  Neodyme magnet 25x5 mm in vertical levitation
Notes : What is difficult here: the cutting of the dodecahedron...
The edges size: 26 mm.
Levitation elevation: app. 16 mm, maximum: 20 mm.
Notes : The magnets control the trim, the field coils become the sustentation coils, the optional altitude coil inserted in the center becomes the horizontal axis stability coil (in substitution of the gravity force).

Geometry #5-6
One makes oblong the circular domain of the geometry #5

the magnet in levitation become free along the long axis of the new domain

Test jig for geometry #5-6
Vido : 100 Ko, 10 s duration (.AVI - wmv9). (click on the picture)
 linear hall sensor  Video: Oscillation of a kind of inverted pendulum
Notes :Inexpensive and compact configuration, 5 field coils, 10 hall sensors and one servo board. This setup permits to make levitate the magnet easily at an elevation of 25 mm. This test jig can be also configured with 10 field coils (5 coils on each sides). In both cases, the coils are oriented at right angle to the longitudinal axis. this setup is nearest of the geometry #5. the properties are slightly differents. more infos in Tech's page Notes : The adjustment of passive stopping fields at each extremity permits to curve the trajectory by the creating an "hight point" at the center of the stability axis, thus we can get the motion like the one shows on the video.
The using of a laser beam for to guide the magnet along is displacement axis is very effective.

more infos in Tech's page

Geometry #6

if one removes the passive stopping magnets and
closes on itself the oblong domain of the geometry #5-6

We get a circular domaine allowing the positioning of the magnet in levitation at any location

Test jig for geometry #6 applied to a platform free to rotate
Video : 400 Ko, 10 s duration (.wmv). (click on the picture)
Test jig for geometry #6 used as geometry #5.
 Video: to levitate a plateform free to rotate  Geometry #5 in center of #6
Note : The platform comprises 24 neodymium magnets (12 in this experiment) wich are set as crown at the periphery and one magnet at the center as reference of the geometrical center (used for stability control). The weight is not anymore a problem compared to the precedent geometries, the platform is free to rotate 360 around is vertical axis, therefore we get preferencial stopping points each 15 (30 in this experiment) consequence of using discret magnets instead of one ring magnet. This setup permits the fast rotation of the plateform in the way of a elementary magnetic bearing. (click on the picture)

Others details in page Tech's.
Note : Without any changement, we can levitate a magnet in the center of the test jig, we find at this center of the geometry #6 the elements of the geometry #5 not optimized but functional.

Others details in page Tech's.


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