Difference between revisions of "Levitation"
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Beside thermally induced dipoles there's also a not yet well understood but certainly practical relevant component of the Van der Waals force | Beside thermally induced dipoles there's also a not yet well understood but certainly practical relevant component of the Van der Waals force | ||
| − | that originate from the suppression of non harmonic modes of heat radiation in nano to micro scaled gaps. | + | that originate from the suppression of non harmonic modes of heat radiation ( ... virtual particles ... ) in nano to micro scaled gaps. |
Certain geometries like an elongated ellipsoid over a circular hole in a plate) lead to static levitation. | Certain geometries like an elongated ellipsoid over a circular hole in a plate) lead to static levitation. | ||
['''Todo:''' find out why this shape] | ['''Todo:''' find out why this shape] | ||
Revision as of 21:35, 21 May 2014
With Levitation one can bear very high speeds in a very small space when load isn't excessive.
Contents
Methods
Dynamic electrostatic control
Some form of electrostatic sensor is needed.
A lot should be nown from MEMS here.
Electrostatic lagrange points
Mechanically forcing two equal e.g. positive charges with sufficient difference in charge [factor 24.65 = 25/2+sqrt(621)/2] to circle around each other around their hypothetical barycenter with their hypothetical natural rotation period gives two stable Lagrange points in L3 L4 for small charges of the opposite sign - just like in celestial mechanics. The ability to deviate from the natural movement might allow for further optimisation of the stable points. [To inverstigate: is there a better and if is there an optimal configutation] The usefulnes of this isn't quite obvious.
Note that any (sufficiently isolated) zero dimensional nano sized object is subject to quantum mechanical wave dispersion.
Casimir force
Beside thermally induced dipoles there's also a not yet well understood but certainly practical relevant component of the Van der Waals force that originate from the suppression of non harmonic modes of heat radiation ( ... virtual particles ... ) in nano to micro scaled gaps. Certain geometries like an elongated ellipsoid over a circular hole in a plate) lead to static levitation. [Todo: find out why this shape]
Negative compression bearings
When bushing and axle of a DMME-bearing form an increasingly big but not too big gap the force can switch from inward from all directions to pulling outwasd in all directions at the same time but still provide a stable center for the axle. This lowers the waviness and coupling of the bearing and makes it more levitation like.
This happens whe the shafts surface lies between the minimum and the inflection point of the Lennard Jones potential of the bushing atoms. Going beyond the inflection point (unloaded bearing) makes the axle stick to one side of the bushing. Going for the minimum of the potential leds to zero local stiffness (like in tensegrity structures).
Magnetic levitation
Magnetism dooes not scale well with shrinking size thus it will only be used for levitating macroscopic parts. The manipulation of magnetic properties of diamondoid materials falls unther the non mechanical technology path
Applications
- nanoscale turbomelecular pumps (but the may not be needed since positive displacement pumps do just fine)
- carriage particle accelerators
- moving surface medium movers
