MEMS robots and another way to power the world

MEMS (Micro Electro Mechanical Systems) uses the technology of
building integrated circuits to build mechanical devices on a tiny
scale.

http://en.wikipedia.org/wiki/Microel...anical_systems

This has been used to make tiny robots that can be controlled remotely

http://nextbigfuture.com/2008/06/agi...s-smaller.html

MEMS based rockets have been built

http://www.me.berkeley.edu/mrcl/rockets.html

So, tiny flying robots are possible

http://oai.dtic.mil/oai/oai?verb=get...er= ADA469488


Since the weight of an object varies as the cube of its dimension,
while the surface area of an object varies as the square of its
dimension, the thrust to weight ratio of rockets fans props and wings
increase dramatically as sizes are reduced. Also, the power to weight
ratio of solar powered systems increases as size is reduced as well.

Density of silicon: 2.33 grams per cc
Power of sunlight: 100 milli-watts per cm2

Cube Area: 6 * d^2
Cube Volume d^3

Sphere Area: pi * d^2
Sphere Volume pi/6 * d^3

So, for a centimeter scale device;

Power: 100 milliwatts to 157 milliwatts
Weight 2.33 grams to 1.71 grams

Power/Weight 50 W/kg to 100 W/kg

Which lets us estimate devices of the following sizes

10.00 mm 50 W/kg - 100 W/kg
1.00 mm 500 W/kg - 1,000 W/kg
0.10 mm 5,000 W/kg - 10,000 W/kg
0.01 mm 50,000 W/kg - 100,000 W/kg

Nature has a whole range of 'no-see-ems'

http://en.wikipedia.org/wiki/Fairyfly
http://en.wikipedia.org/wiki/House_dust_mite

http://thelongestlistofthelongeststu...mallest49.html

What can we do with machines such as these?

Well, we can gather sunlight - and since processed silicon costs about
$890 per kg - we can see we can make power at $0.01 per peak watt.
About 10 grams of silicon devices are needed to power a home, or a
hybrid car. 100 grams of silicon devices are enough to power a home
and two cars with synthetic fuel made from sunlight and air.

We can create a fog where the elements communicate with one another
via open optical laser - very similar to the way IR remote controls
work - but at a peta-bit rate. This lets us create a global fog that
provides a global wireless hotspot without satellites or any large
hardware whatever - other than the factory that churns out the solar
powered no-see-ums.

We can also use them as a means to sense the environment and create a
virtual model in any attached computer of the entire world - that can
then be interrogated remotely by any authorized user. So, we could
create a DVR for the whole world and make it available to anyone or
everyone.

Small mites could penetrate any storage container and cover every
document - scanning it and communicating the information to the fliers
- which then communicate it to the virtual reality model - so
documents and in fact all records - could be placed in the virtual
model

A spherical device 0.1 mm in diameter masses 12 nanograms. A fog of
1,000 fliers surrounding every individual on the planet would require
7 billion x 1,000 x 12e-9 grams = 84 kilograms - which costs less than
$84,000 - once the core technology is in place.

A fog of fliers covering the entire Earth with a 1 cubic centimeter
per element - to a depth of 100 meters - would mass 9,600 kg. $9.6
million. Increasing separation to 1 meter reduces this to 9.6 grams -
costing $10.

Clearly, once the core technology is developed - which can be done for
less than $100 million - using an old wafer fab - we could build a
power infrastructure and communication infrastructure and an
information infrastructure that is tremendously important.

Is there any way we can use these no-see-ums for anything else?

Consider Newton's third law of motion;

mv = MV

Imagine a tiny 12 nanogram no-see-um moving at a velocity and hitting
a surface. First, the object is likely not to be hurt. Second, the
no-see-um will impart a force to the object. A large number of
objects will impart a continuous force.

F = mdot * velocity
1 newton = mdot * velocity

With 100 m/sec velocity then

mdot = 1 Newton / 100 = 0.01

10 grams per second - moving at 100 m/sec produces 1 newton of thrust.

800,000 no-see-ums per second at this speed are needed per Newton of
thrust.

Since the no-see-ums may be recycled - creating a current or flow of
particles - the total mass of particles may be quite small. At 100 m/
sec - and moving over say 10 cm - particles may be reused 1,000x per
second - so, 800 particles are needed to produce 1 Newton of force.

So, to lift requires the following amount of material

1 pound (4.46 Newtons) 3,568 particles 0.05 mg
10 pounds (44.55 Newtons) 35,680 particles 0.5 mg
100 pounds (445.55 Newtons) 356,800 particles 4.4 mg
1,000 pounds (4.5 kN) 3.6 million particles 43.2 mg

So, only a few cents of solar powered devices can be organized to lift
anything anyone could reasonably deal with even with Earth moving
equipment. This can be done in any direction, location, and so forth.

Its easy to see that combining the communications, sensing, and
virtual model with a force application - would allow people to do
useful work anywhere from anywhere. An apple could be identified
picked by remote control - and carried to anyone anywhere.

People could know what others are doing or have done. People would
also have the capability of acting anywhere upon this knowledge.

The ability to do good, or not, of all people will be greatly
magnified.