The following update has been appended to:
http://mtaonline.net/~hheffner/ZPE-CasimirThrust.pdf
my "ZPE-Casimir Inertial Drive" article.
If I made no simple calculation error the prospective performance of
this design, even at fairly large element sizes, is startling. Using
nano-technology the performance could be improved by orders of
magnitude.
Update 8/9/2009:
Another design for a Casimir thruster, based yet again on the premise
that matter within a Casimir cavity has reduced inertia, is based on
oscillating a nano-structure beam into and out of a Casimir cavity.
A microelectromechanical system (MEMS) beam can be electronically
activated as a pendulum which oscillates in the MHz range. For
example, see US Patent 6,531,668. An array of beams are created in a
sheet array which can be placed over a plate with matching grooves
in it located so as to act as cavities for the beams when acting as
pendula. The beams then oscillate into and out of their repsective
cavities. When the beams are down in their respective Casimir
Cavities they all accelerate in a direction toward out of the cavity,
and when out of the cavity they accelerate in a direction toward
their cavities. This is an ideal arrangement for creating thrust in
the direction towards out of the cavities, because the beam ends will
have less mass when in the cavities.
For a very rough performance estimate, suppose silicon beams are used
that are 100 microns long, thickness 2 microns, and width 5 microns.
Assume only the far half of the pendulum is active in producing
force, giving an active volume 50 microns long, with thickness 2
microns, and width 5 microns. Using 2.33 g/cm^3 for silicon, we have
an active mass of 1.165x10^-12 kg. Assume it swings to a depth of 5
microns into the cavity, and at a rate of 4 MHz. Its total swing is
10 microns, so it covers that distance with an average velocity v of
(10 microns)*(2 * 4 MHz) = 80 m/s. It changes from v to -v twice
each 1/(4 MHz) = 2.5x10^-7 seconds, giving an average acceleration of
2*(80m/s)/(2.5x10^-7 s) = 6.4x10^8 m/s^2. Suppose the Casimir
cavity mass change is 1/100th the gross mass. The effective mass is
then (1.165x10^-12 kg) * 0.1 = (1.165x10^-14 kg) . A net force f =
m*a = (1.165x10^-14 kg)*(6.4x10^8 m/s^2) = 7.46x10^-6 N = 7.6x10^-7 kgf.
Assume the cavity plates are 30 microns thick and the beam support
plates are 30 microns thick, for a layer thickness of 60 microns or
16,600 layers per meter. Assume the beams are repeated every 10
microns laterally, or 100,000 per meter. Assume the beams are
repeated every 150 microns, or 6,600 per meter. The number of beams
per cubic meter is then 16,600 * 100,000 * 6,600 = 1.1x10^13. The
total force per cubic meter of pendula is then (1.1x10^13) = 8.3x10^6
kgf, or 8,300 metric tons. Now that is robust! If the Casimir
cavity induced mass change is only 1/100,000, then the trust per
cubic meter of pendula is 8,300 kg. Still robust! This is clearly
the preferred method.
Best regards,
Horace Heffner
http://www.mtaonline.net/~hheffner/
