ABSTRACT
Electrostatic microactuators remain a subject o f research interest and devel opment, and as such are not yet available on the general commercial market.
B. Electromagnetic Actuation Electromagnetic actuation is not as omnipresent at the micro-scale as at the con ventional-scale. This probably is due in part to early skepticism regarding the scaling o f magnetic forces, and in part to the fabrication difficulty in replicating conventional-scale designs. Most electromagnetic transduction is based upon a current carrying conductor in a magnetic field, which is described by the Lorentz equation:
dF = IdlxB
where F is the force on the conductor, / is the current in the conductor, / is the length o f the conductor, and B is the magnetic flux density. In this relation, the magnetic flux density is an intensive variable and thus (for a given material) does not change wi th scale. Scaling o f current, however, is not as simple. The resistance o f wire is given by:
gized sequentially to rotate the stator.
