Re: starship-design: HIGHLY OPTIMIZED TOLERANCE

[STAR1SHIP@aol.com]

In a message dated 3/19/00 7:36:42 AM Pacific Standard Time, 
bfranchuk@jetnet.ab.ca writes:

> John Bean wrote:
>  
>  > I don't know if I agree with the make-everything-myself idea when it 
comes
>  > to really complicated processes that are really expensive such as chip
>  > making. At some point you need to repair/replace the "table top wafer 
fab"
>  > and the technology to do that would have to be carried. Then that
>  > technology needs to be repaired so you need the technology to do that. 
> This
>  > goes on forever with each iteration adding weight, complexity and cost.
>  >
>  
>  That is only true, with a evolving system. The Critical components
>  would be fixed in design. Barring the latest PC clone I can see only
>  50 - 60 different kinds of semi-conductor components. A air circulating
>  fan
>  does not need a 1 GHz 64 bit cpu to control it.
>  
>  > 
>  > Also making chips is not as simple as a wafer lab according to the guys 
> who
>  > are making custom chips for me. The process is big by nature, requires 
> lots
>  > of energy, lots of chemicals and consumables, very skilled people and
>  > ultra-high tech ultra expensive equipment. These guys snicker or drool
>  > whenever you talk about a small or inexpensive or easy prototype machine
>  > like you are discussing.
>  >
>  
>  That is true, but semi-custom chips require less processing, at say a
>  30%
>  loss in speed and processor size. High density programmable logic,
>  providing
>  that they be used wisely and you don't have problems with bit rot in the
>  chips
>  that could really cut down the number of spares needed.
>  
>  Right now I am working with a semi-custom design package, ( free on
>  linux )
>  with rather slow logic ( 1 ns gate + 1 ns/pf ) to design the ttl logic
>  processor I always wanted to build but never could make up my mind on 
>  the instruction set. Since I started programing computers on the PDP-8,
>  a classic micro-controler with 4 k-words of core memory, I have this
>  dislike
>  for bloated code.

As my first PC was a Commadore 64, they were masters at minimum code writing. 
They were doing thing with games, multimedia (video toaster) that only 
recently bloated code on present humongous PCs are doing. It would seem that 
you need to focus on your instructional set and not chip technology to 
accomplish what you want, Basic computer architecture has remained the same 
with miniaturization (and the increased speed with it) being the main 
progress. That not done by hardware can usually be done by software.

> Anybody need a 24 bit processor chip ... coming real
>  soon. I am sure that even the old 8 could handle control of the fusion
>  reactor or plasma drive.The PDP-8S ( slow ) was a neat all transistor
>  ( 1001 of the suckers) computer.
>  
>  You only need computing power for graphics,games
>  and multi-media. People stuff, not ship running stuff.

True. I use analog computer processors for ship guidance. This inertial 
guidance system takes data from sensor input, processes it in real time and 
delivers the output analog data to the control servos. A robust method that 
eliminates the fragility of present slow miniaturized processor chip 
technology.
 
>  > Even if you could create this machine and have it weigh 100 pounds with 
> 100
>  > pounds of support stuff, excluding consumables, and 100 pounds of spare
>  > parts and equipment it becomes really heavy and would cost millions of
>  > dollars. I don't know how to figure out the weight of the person to 
> operate
>  > this or the supplies he needs. This also ignores the toxicity of some of
>  > the processes.
>  
>   Very heavy!? you just said 300 lbs. Most likely 3,000 lbs and the same
>  for support stuff. Note this would be at the trailing edge of technology
>  as most of the design stuff would be simple devices.
>  
>  > 
>  > A better suggestion may be to design a "generic" logic module using 
modern
>  > technology. I'm not suggesting a few gates on a board as in the 80s I am
>  > suggesting a 32 Bit ARM processor, a DSP, 160k of program flash, 8Mbits 
of
>  > data flash, 12k of RAM, a USB port, an IRDA port, some A/D channels, some
>  > D/A channels, somer general purpose IO pins. This could be built on a 2x3
>  > board that uses very low current (50ma with both CPU and DSP cooking at
>  > 22/80 mips) at 3.0 volts using available (off the shelf) technology for $
> 20
>  > a board in medium volumes at about 2 oz a board.
>  >
>   YUCK !!!
>  
>   Eprom,Dynamic ram,Flash,Cmos all have a limited life span (10
>  years),zapped easily
>  by cosmic radiation and just is over kill for many things.. Low density
>  bipolar fuse based logic looks to be more rugged in a space application
>  for critical
>  things.

SInce the first PC was made from one of the parrallel processor chips from a 
supercomputer and given a reduced operating instruction code,, I reasoned 
that the many XT PC's with a few AT's laying around could be hardwired back 
in parallel (with Novell hardware and Lan Assist software. I then wrote the 
expanded operating code to return the hardware to the super computer status.

Massive failures (rare) in any or many of the parallel processors (100 in 
number) failed to bring the computer down. In a RAID type array each of 3 
instruction sets can be compared and the majority bit by "majority" vote sent 
to the central processor for actual use. This and other techniques would 
allow such a space faring computer to obtain many bit destroying cosmic 
collisions without destroying the integrality of the data and its primary 
function. 

Example: Oxide memory storage disks can have many holes (from cosmic 
collisions) in coating and still work as the bad spots are mapped and the 
data written to and beyond the hole and retrieved in the same manner. Any 
storage device with the redundant data comparison instruction set can route 
and go around a faulty chip address in the parallel set allowing the data 
processing integrity. Wriiteable CD storage devices would be less susceptible 
to magnetic storms encountered and the same repairable redundancy technology 
be used. Since present hard drive technology available for retail have their 
heads flying in air of the oxide (or other surface) they are not useful and 
crash in the vacuum of space. That is a fixable problem with pressurization 
though hard to maintain with robotic probes. (again micro meteor collision)

>  
>  > 
>  > In place of your 300 lbs of machine you could carry 2400 spares for 
$48000.
> 
>  > Considering a desk-top fab will probably cost Millions, which excludes 
the
>  > packaging and testing equipment also required.

Only a few thousand if you use obsolete processors with a nifty instruction 
set.

>  
>    Funny last time I looked at star-ship prices that was in the travelers
>  role-playing game and they where not cheap. For a fleet of 12 ships
>  custom
>  design was only 10%. I place this as a .1% cost modification.  
>  
>  > 
>  > The real difference is that you have to get used to the concept that in
>  > some things, such as modern electronics, you are often better off to 
throw
>  > a bunch of parts at a simple task than to make something custom.
>  >
>  
>  Is not that the same thing, custom chips only are the bunch of parts
>  all on one chip rather than a PC board.
>  
>  > 
>  > If you need to interface a full keyboard use one of these boards and also
>  > use one to interface to a single switch. The idea is to have so many of
>  > them that it just doesn't matter. If the initial design used this 
approach
>  > there would be thousands of these boards in a starship spread through
>  > critical (life-support) and non-crital (personal entertainment) systems.
>  > Take some multiplier of these as spares and you would be covered for many
>  > decades.
>  >
>    Take keyboards - I want a just a keyboard , not a key board with
>  trackball, infrared remote and windows keys just to punch up the
>  commands to "leave orbit"
>  or "hyper speed 3.623".


Ok, but I will just use a joy stick and throttle sensors from my analog 
computer. As the human brain is one of the best and biggest analog computers 
around (especially mine ;=)), I will take 20 other brains from 
starship-design list or clone of mine with me for redundancy. :=)

>  > Since many of the boards will be used for different types of tasks a
>  > particular failure on one part of the board would not prevent the board
>  > from being used in another location. For instance if an AD failed switch
>  > that board to some task that doesn't use the ADs and take the one from 
the
>  > task that didn't use the AD. This provides some redundancy without even
>  > reaching into the spares.
>  > 
>  > This approach can be applied to other technology issues also. For 
instance
>  > only use two kinds of displays, a big one and a small one, and make sure
>  > the big one can do the job of the small one. Then carry spares, mostly of
>  > the big ones.
>  
>   That is the best way to design it.

Each of the twenty crew members will have three (one operating) PC's net 
worked together but each capable of operating independently to handle all 
ship computer needs.
  
>  > Another way to extend the mission duration is to send supply ships ahead,
>  > or send them faster from behind with some replacement stuff. Since 
"stuff"
>  > doesn't need gravity or environmental controls or oxygen or food or water
>  > it can be moved much faster and much cheaper than we can move people.
>  > Although re-supply may be distasteful to "pure" starship travel the
>  > reallity is that even here on earth it was, and is, considered normal.
>  > Aircraft carriers and submarines and space stations do it, the only
>  > difference is distance.

Brilliant technique there to extend both range and journey there. First used 
by nomads crossing uncrossable deserts. Supply trips buried supplies further 
and further out so the trip could be made. Non manned supply ships are not 
limited by the constant 1 g acceleration required for human cargo and so can 
be accelerated to a constant 15 g before supply integrity fails.
>  >
>    Or move more at a slower speed, only "living" things need to be moved
>  fast.
>  
>  > 
>  > Considering FTL isn't going to happen soon, if ever, it is probably safe 
> to
>  > assume that we would go pretty slow in a colony ship.

Speak for yourself please :=)

> If a supply ship can
>  > go 1.5 times faster at 8 months we send one with the first resupply
>  > reaching us at the 1 year point. Assuming engines will keep getting 
better
>  > perhaps the next supply ship is launched at 18 months and reaches us in 2
>  > years. Radio will still be effective so we can provide them with a 
> shopping
>  > list even if it is taking weeks or months for it to reach earth.
>  > 
>  > Personally I don't think we will be going to reach the stars soon.

wrong. Hell I am already there. :=)


> However,
> 
>  > I think starting to travel is critical to our survival just like setting
>  > out in doughouts was to most early sea fareing nations.

Considering the frailty of space ship earth and the MAD atomic policy such a 
journey would seem most necessary to mankind's survival.

Best Regards,
Tom


> I think that our
>  > travelers, now in space for 15 years, will be stuned when some kid pulls 
> up
>  > in his dads Mach5 with his FTL Quantum drive with the Window's logo on it
>  > and says "haven't you heard, Bill Gates bought NASA, now everyone has an
>  > Intel FTL drive in their family car. Other than having to turn it back on
>  > every hour and the occasional warping into a star it works great"
>  
>  LOL

Ditto
 <A HREF="http://members.aol.com/tjac780754/indexb.htm">Plasma Rocket Engine</
A> 

>  -- 
>  "We do not inherit our time on this planet from our parents...
>   We borrow it from our children."
>  The Lagging edge of technology:
>  http://www.jetnet.ab.ca/users/bfranchuk/woodelf/index.html
>  
>