Page 16 - trends in automation

P

hysics always draws clearly

defined lines. The transition from

one state of matter to another –

solid to liquid, liquid to gas – is a

perfect example of this. The same is true

of superconductors. The metals, metal

compounds or ceramic materials abruptly

enter a superconducting state below a

certain transition temperature. When this

happens, they lose their electrical resist-

ance. This opens up fascinating new

perspectives for technical applications.

For example, if a superconductor is cooled

to below the transition temperature under

the influence of the external magnetic

field of a permanent magnet, it can store

or ‘freeze’ the magnetic field of the per-

manent magnet at a predefined distance

and thus create a stable floating condition.

The superconductor responds to any

attempt to move it by returning to the

stored position. In contrast to electromag-

nets, this characteristic of a frictionless,

stable bearing does not need complex

measurement and control technology.

Gliding on the rocker

To experience what it is like to hover

using superconductor technology, Festo

has developed SupraLinearMotion, a

rocker with a seat for one person mounted

on a slide. To make the rocker hover, the

superconducting material on the bottom

of the slide is cooled to a constant tem-

perature between 63 and 77 Kelvin using

liquid nitrogen and placed at a distance

of around 15 millimetres above a rail

made from permanent magnets. The

superconductor stores and maintains the

defined position parallel to the rail. To

move the slide, the rocker is taken off

balance. The passenger hovers in the air,

carried only by superconductance.

Frictionless handling

In the SupraHandling system, the principle

of the superconductor rocker has been

transferred to an X/Y-table for moving

objects in a level plane. Two drives

attached beneath the table tilt the base

plate in the X and Y direction indepen-

dently from each other and thus move

two hovering slides on magnetic rails

with superconductive bearings. As with

With SupraLinearMotion

the passenger

glides noiselessly and friction-free over

the magnetic rail.

Superconductor technology for automation

Frictionless movement

Superconductors work by hovering,

are resistance-free and energy efficient. They offer

new potential for sustainable production techniques for the future. Festo has developed the

first superconductor applications for automation technology in three projects carried out in

cooperation with the company evico and other partners from research and academia.