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Posted: Mon Feb 16, 2009 7:51 pm
by MSimon
jgarry wrote:Anyone know anything about fiber optic control of servos?
I know a lot about serial buses. Fiber is just different hardware.

Posted: Mon Feb 16, 2009 8:52 pm
by jgarry
I've been toying with the idea of a fly by wire submersible. It occurred to me that fiber would be the wire to use, because of weight. But I believe that fiber doesn't bend well, so perhaps not.

Posted: Mon Feb 16, 2009 11:25 pm
by krenshala
jgarry wrote:I've been toying with the idea of a fly by wire submersible. It occurred to me that fiber would be the wire to use, because of weight. But I believe that fiber doesn't bend well, so perhaps not.
The bending depends on the fiber. Some can bend pretty well, others not so much. My info comes from when I did installation of multi-mode fiber optic network cabling (I helped run and put connectors on the ends of about 30k feet of fiber for 5k computer terminals about 15 years ago). The fiber we used for that wasn't as flexible as CAT-V network cable, but it was pretty close. Call it a six inch radius curve before you started worrying about fractures in the fiber.

Posted: Tue Feb 17, 2009 1:51 am
by MSimon
jgarry wrote:I've been toying with the idea of a fly by wire submersible. It occurred to me that fiber would be the wire to use, because of weight. But I believe that fiber doesn't bend well, so perhaps not.
Copper wire has a lot to commend it:

1. ease of installation
2. low prices
3. bidirectionality is easy
4. No repeaters required for multidrop buses

And probably a few others.

TSP has pretty good noise immunity.

Where fiber excels is in isolation. (ground loops and high voltage)

Posted: Tue Feb 17, 2009 3:10 pm
by jgarry
I'm a tad busy right now. People I work for are expecting something to be done. The nerve.
But I'm thinking of trying to do something a bit more involved than a typical RC sub, but nothing like the advanced submersibles that uncovered the Titanic. Fly by wire that could operate at moderate depth, with a web cam. Actually an ordinary serial or network cable would probably be adequate.

Posted: Tue Feb 17, 2009 4:07 pm
by MSimon
jgarry wrote:I'm a tad busy right now. People I work for are expecting something to be done. The nerve.
But I'm thinking of trying to do something a bit more involved than a typical RC sub, but nothing like the advanced submersibles that uncovered the Titanic. Fly by wire that could operate at moderate depth, with a web cam. Actually an ordinary serial or network cable would probably be adequate.
Why didn't you say so. I thought the fiber was for internal wiring.

It makes sense if you are going to use it for video and control in a tethered situation. For that fiber that could handle two fairly widely separated light wavelengths would be excellent. About 10 MBs should be a cake walk. Up to 100 MBs (for the video) should not be too tough.

I thought I saw some stuff like that in the Mouser Catalog (bed time reading) the other day.

http://www.mouser.com/catalog/637/154.pdf

Posted: Thu Feb 19, 2009 7:53 pm
by ravingdave
My latest intrests are CNC maching using G-code and M-code. Specifically maching ceramic materials. I have my own Tormach CNC milling machine with a 4th axis, and it can do some pretty neat stuff. (like convert a bmp file to engravings in aluminum or steel. )

I've been doing a lot of carpentry lately, I like doing mechanic work from time to time, singing, dancing, playing the piano, teaching my kids how to make things, watching movies with my family and friends, (zombie movies and old comedys) making costumes, casting metal, building stuff, and occasionally opining on Polywell and Poly-tics. :)


David

Posted: Fri Feb 20, 2009 2:24 am
by Torulf2
Making 3D cg art.
RPG paper and table type.
Collecting beetles.
Anime
Trying to understand scientific things as astronomy, ecology and fusion power.

Posted: Fri Feb 20, 2009 2:28 am
by MSimon
ravingdave wrote:My latest intrests are CNC maching using G-code and M-code. Specifically maching ceramic materials. I have my own Tormach CNC milling machine with a 4th axis, and it can do some pretty neat stuff. (like convert a bmp file to engravings in aluminum or steel. )

I've been doing a lot of carpentry lately, I like doing mechanic work from time to time, singing, dancing, playing the piano, teaching my kids how to make things, watching movies with my family and friends, (zombie movies and old comedys) making costumes, casting metal, building stuff, and occasionally opining on Polywell and Poly-tics. :)


David
Twenty-four seconds of zombie gold.

http://www.youtube.com/watch?v=7XjCory-9y8

Posted: Mon Feb 23, 2009 8:42 pm
by ravingdave
MSimon wrote:
Twenty-four seconds of zombie gold.

http://www.youtube.com/watch?v=7XjCory-9y8

That's a hoot ! As a corollary, my nephew always used to say... "Everybody knows all the deap people vote democrat. "

:)


David

Posted: Thu Jun 11, 2009 3:43 pm
by BenTC
jgarry wrote:Anyone know anything about fiber optic control of servos?
Terminating single and multimode optic fibre is hard. You might want to try starting with Plastic Optic Fibre. Not that I've had a project to try it out yet, but apparently it can be terminated with a pair of scissors. Limited to 100 meters length. 25mm bend radius.

http://www.timbercon.com/Plastic-Optical-Fiber

http://www.firecomms.com/products-optolock.html

http://www.dimoto.com.au/technology.html

http://www.timbercon.com/Ruggedized-Products/index.html

Posted: Sat Jun 13, 2009 1:24 am
by choff
Anybody remember this?
http://www.amctv.com/videos/the-prisoner-1960s-video/
There's a remake coming out in November. Allededly based on a true story.

Posted: Sat Jun 13, 2009 2:42 am
by kunkmiester
Arts, mostly. I'm trying to get into robotics, but the programming is killing me. Had a nice intro to C++, but not so much about linkers and compilers and how to shop for and use them. I suppose I should try to find some more info online, but I'm partly lazy, and partly I don't learn on my own very well.

As for the arts, I'm trying to learn to draw, and I'm getting into making fursuits. Some of that here:
http://www.furaffinity.net/user/watcherinthewater/
I also try to write every once in a while, but I don't have much of that on the web.

Posted: Sat Jun 13, 2009 3:24 am
by Tom Ligon
Writing science fiction, singlespeed and fixed-gear bicycling (preferably on antiques, and 100-mile distances), old tools and learning the skills to use them, do-it-yourself solar projects, following science and technology news.

I like music and wish I had time to create some. I'm a fair poet/lyricist. I'd love a chance to write and produce an opera based largely on Beach Boys tunes (I figure if Abba can do it, this project would be a slam dunk). "The Wreck of the John B." I've had a couple of cartoons published.

Posted: Mon Jun 15, 2009 3:48 am
by BenTC
kunkmiester,

You may want to look into using the Arduino Platform with the Processing Language. Its aimed at artists and non-technical people wanting to do control. Its C++ at its core but no (explicit) linking or compiling. Just click the Upload button to load your program into the microprocessor. When mine arrive I got the first program loaded into it and running within an hour using this procedure, for which the source program is here.

Some of the things people are doing with Arduino...

http://www.instructables.com/id/How_to_ ... Robot_SER/

http://www.philipbeesleyarchitect.com/s ... AtWork.pdf

http://www.arduino.cc/playground/Projects/ArduinoUsers

cheers, Ben