Rack and pinions are neat - and naturally the mirror that is controlled to create
pixels... I don't know - but suspect (as it was planned at one time) that the new
Sony super duper - double density HDTV twice the pixels - uses that technology.

Life member - Electron Device Society IEEE
Martin Eastburn
@ home at Lions' Lair with our computer lionslair at consolidated dot net
NRA LOH, NRA Life
NRA Second Amendment Task Force Charter Founder



Don Stauffer wrote:
I have seen micromachined electric motors, air turbines, and gas
turbines. Most folks I know consider gas turbines IC, because the
"engine" they consider includes the compressor, burner cans, and
turbines together, hence IC.

I have yet to see a micromachined piston engine, either 2 or 4 stroke.

One reason for turbines is that the small size allows VERY high rpm
without excessive inertia loads. Also, the very tiny valves for a 4
stroke would be more of a problem than for a turbine.

The blades on the air turbine and gas turbines I have seen are NOT a
very complex shape. How complex they need to be depends a lot on the
operating conditions, particularly the ratio of blade chord to mean free
path, which is of course a function of temperature and density.

wrote:

2005-11-24

To: news:rec.crafts.metalworking

Hey, gang! Feeling better lately. Getting ready for Thanksgiving.

In Kinematic Self-Replicating Machines

© 2004 Robert A. Freitas Jr. and Ralph C. Merkle

the authors mention actual machine tools in section 3.12. I am
wondering if 4-stroke, 2-stroke, or turbine engines would make the best
prime movers for a self-powered self-reproducing machine tool (SPSRMT).
You see, we distribute power with electric wires now, to various types
of tools: machine tools, power hand tools, stationary power tools. If,
as these authors propose, certain design changes can be made to produce
a universal tool, it would only require a single prime mover. Now,
electric machines are difficult to produce with machine tools, but
engines are not.

So I am now asking for any comments on internal combustion,
self-powered, self-reproducing universal machine tools.

A few random thoughts:

It seems like complex turbine blades are out of reach. So that's why I
titled this post with IC. Turbine engines are technically EC. But hey,
if it's in the machine capability, turbines could be an option.

Jet A and other purified kerosenes constituting rocket fuels might be
appropriate as a fuel base because the whole field of SRMT technology
is related to the colonization of space. Only in the extreme case of a
seed ship carrying SRMTs to a destination colony would the nature of
this technology be required. It can't compete here on Earth; it's too
costly compared to mass production of machine tools. I don't see a use
for LOX in the shop unless it's in a compact welding unit. Kinda
dangerous stuff. Powering machine tools on H2; any thoughts on that?

The authors above do not mention the utter primacy of the
anneal/machine/harden/temper sequence as it applies to carbon steel and
a few other materials in shop operations. It is the lever by which the
Industrial Revolution was lifted from its base. I'd like to hear more
on this. Does anyone here remember carbon steel lathe bits, or are we
all too young for that?

I have learned from that two cylinders are optimal
for self-repair of a motorcycle; when one goes bad, you have one left
to either limp home on or provide motive power and battery energy with
which you can debug the other. My latest bike has Direct Injection
Technology in a 2-stroke. However this is controlled by semiconductors.
What's a simple reliable, *easily built* 2-cylinder engine; a diesel?
Some design already on road or in use?

Compressed air has uses in the shop; is there an integrated
engine/compressor design capable of enough pressure to form liquid air,
from which LOX and LN can be separated? Maybe one that can run on four
cylinders at full power, or two at half power, or on two driving and
two compressing cylinders, with little useful mechanical power output.
Is there some ratio to be had, assuming modular cylinders, between the
work of compressing air and the work available from an engine cylinder,
something in the low integers? I just proposed that this ratio be 1:1.
Should it be 4:1? 8:1?

My apologies for any spelling errors.

The Dougster
Replikon Research
Falls Church, VA 22044-0394
email


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