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Jones on stepping motors found via google

Seems like stepper motors are not that difficult to control. A simple darlington transistor, resistor, and diode are all that's needed for the driver, for the control circuitry I suggest Atmel AVR microcontrollers, some of them have built in A/D etc, they're cheap, and they are programmable via GNU C compilers available under linux.

Get a Dontronics rAVeR to run the control circuit.

An AVR running at 10 mhz gives you a lot of processing power, and plenty of i/o to step 2 motors forwards and backwards. The main question is how to tell the AVR what to do.

It depends on how complicated your control algorithm is, ie. do you just need to run through a set of rote steps, or are you doing feedback control, or responding to the outside world?

If you're doing feedback control, then get an AVR with A/D channels built in, if you're responding more complicatedly then perhaps use the sound card output of your computer to tell the AVR what to do?

Admittedly all of this is likely more trouble than installing windows and writing your software in VB, but once you've done it, you've got a system that you can have some control over vs. an off the shelf solution from a non-responsive vendor (ie. there's not necessarily a guarantee that the thing works all that well under windows either)

Plus, with this kind of experience you will rapidly find other uses for a general purpose microcontroller platform, you'll be able to bypass buying expensive proprietary PCI cards and build some of the simpler control systems you need yourself.

NOTE: if you're building things yourself you have to deal with debugging the hardware and the software. Keep focused on the cost to benefit ratio of doing it yourself vs. buying off the shelf. Remember you're trying to do research, which means you need the flexibility of do-it-yourself, but you've also got a hard enough time doing the research, so adding hardware design and debugging on top is added hassle.

Getting an undergraduate electronics engineer to work with you for work-study credit is probably a good idea.

The problem isn't that Excel comes from MS or that it is closed source (except in a round-about way): the problem is that the flaws which make Excel unsuited for statistical analysis don't affect sales enough to justify the cost of fixing them.

I think that this picture says it all.

Yep, I know what combinational logic machines are-- I've built several. They're logic systems where the output is dependent only upon the current states of the inputs: that is, they're memoryless. They contrast with sequential logic systems that have "memory" and the current outputs are dependent not only on the current input values, but also on previous output values.

My point was that his fuzzy concept of "operations" is nothing more than the idea of "instructions." A short while ago I did a paper design and simulator for a "one-instruction" computer based on Douglas Jones' Ultimate RISC. I've seen several people argue that it's not a "one-instruction" machine at all; the memory-mapped ALU operations are individual instructions where the opcode is encoded in the destination address.

Yep, I know what combinational logic machines are-- I've built several. They're logic systems where the output is dependent only upon the current states of the inputs: that is, they're memoryless. They contrast with sequential logic systems that have "memory" and the current outputs are dependent not only on the current input values, but also on previous output values.

My point was that his fuzzy concept of "operations" is nothing more than the idea of "instructions." A short while ago I did a paper design and simulator for a "one-instruction" computer based on Douglas Jones' Ultimate RISC. I've seen several people argue that it's not a "one-instruction" machine at all; the memory-mapped ALU operations are individual instructions where the opcode is encoded in the destination address.

Thanks -- that jogs the memory cells a bit. I also found a page that describes the level and how to finish it (text without screenshots, sadly). I seem to remember it was harder than most of the other levels, comparable perhaps to the last level.

Genetic engineering != eugenics. They're two completely different ideas.

NASA has published a brief history and a depiction of the plaque.

NASA has published a brief history and a depiction of the plaque.

The G4 are the 7xxx series: 7410, 7441, 7445, 7451, 7455.

What's curious is that the PowerPC G4 (7400 series) processors have part numbers eerily similar to the names of discrete logic parts: 7410 is a triple 3-input nand gate; 7441 and 7445 are 4-bit BCD to 7-segment LCD signal converters; 7451 is a dual AND-OR-INVERT gate; 7455 is a 2 wide 4-input AND-OR-INVERT gate.

Unless you happen to be Al Gore...in which case, YOU are the one responsible!

This is one of the two memes about the internet that really bugs me. If you are going to criticize someone, criticize them for what they actually said, not for what their critics say they said, for crying out loud.

Gore never claimed to have "invented" the internet. During a CNN interview he said "During my service in the United States Congress I took the initiative in creating the Internet."

So, who did create the internet? Well Vinton Cerf and Robert Kahn were the guys who lead the development of TCP/IP, so their opinion should carry some weight.

And this is what they had to say about it.

I imagine that if Gore had been writing, rather than speaking off the cuff, he may have prefaced the word "initiative", and said, "legislative initiative" or "political initiative". And if Cerf and Kahn are to be believed, this would be a very fair assessment of his role.

I didn't know of his efforts, prior to reading this article. Reading it earned him my respect.

Particularly when you consider what George W. Bush was doing during this time. When was dubya a drunk and a coke-head?

The other meme that bugs me is that "the internet was designed to survive a nuclear war." You don't believe that one too, do you crawdaddy?

I am going to go off-topic in this last paragraph, and suggest slashdot readers take a look at the portion of Douglas Jones's homage to the punch card devoted to analyzing the questionable voting machines used in Florida./a?

There's a project called Hank supported by the NSF and Ford that would make a nice environment for such a thing.

Actually, no joke. There've already been studies which show that this kind of crap is actually more dangerous than talking on a cell phone while driving (itself as dangerous as drunk driving), because a voice interface to a Web page is so awkward.

for the lazy click here

well, at least this sounds better than when i decided to translate the windows binaries into sound . . .

My interpretation is that he found that the massive undercounting of Al Gore's votes was a predictable artifact of the machines chosen and the ballot layout.

If a partisan person, who knew about this defect of the machine, was designing the layout of the ballot, they could take advantage of this flaw to skew the election results.

I recently took a class taught by a computer science professor who is also on the state of Iowa election machine panel. He brought the worlds of mark sense scanning, human factors and politcal realities together. He has a wonderful page of resources, historical cases and technical mumbojumbo and I offer it to you, the /. community: Douglas Jones's Electronic Voting Resources

Well, eleven months ago Douglas Jones submitted an article to the RISKS digest pointing to an longer online article that explained in detail how all the spoiled Gore votes arose . It turns out the debacle was completely predictable. It was due to a known artifact of those particular voting machines. One which had caused a scandalous shortfall in those same counties, in a Senate election in 1988.

Briefly, Jones disassembled an example of the votomatic machines in question. He found that there was a structural bar behind the slots through which the chads were to be poked. Jones's investigation proved that candidates whose holes were to be punched over those bars were practically guaranteed to jam. Whoever designed the ballots laid them out so Gore's chads were directly over that bar.

Slashdot editor Michael's comment on voting reliability and trustworthiness strikes me as naive. Don't worship the technologoical fix! Michael addresses providing an audit trail for the vote casting and tabulation software. This is not as important as providing an audit trail of the actual votes cast.

Well, eleven months ago Douglas Jones submitted an article to the RISKS digest pointing to an longer online article that explained in detail how all the spoiled Gore votes arose . It turns out the debacle was completely predictable. It was due to a known artifact of those particular voting machines. One which had caused a scandalous shortfall in those same counties, in a Senate election in 1988.

Briefly, Jones disassembled an example of the votomatic machines in question. He found that there was a structural bar behind the slots through which the chads were to be poked. Jones's investigation proved that candidates whose holes were to be punched over those bars were practically guaranteed to jam. Whoever designed the ballots laid them out so Gore's chads were directly over that bar.

Slashdot editor Michael's comment on voting reliability and trustworthiness strikes me as naive. Don't worship the technologoical fix! Michael addresses providing an audit trail for the vote casting and tabulation software. This is not as important as providing an audit trail of the actual votes cast.

My two cents:

I graduated from The University of Iowa College of Engineering during Dean Miller's last year. (As the article mentions, Miller is now president of Olin College.)

This concept is very appealing to me. The UI COE prides itself in a student body comprised of those who are "engineers and more." This is one of the reasons I choose to attend Iowa over That Other School. Admittedly, Iowa's curriculum is not much different from the basic curriculum of any other ABET-accredited school. (BTW, we were required to take Rhetoric, like all UI grads, and a number of courses in the humanities and social sciences. In fact, to fulfil, say, the humanities requirement, you had to take a lower-level and upper-level course in the same field.) Yet, the exposure to, and opportunity in, many diverse areas was invaluable. As a hiring manager, I would be very reluctant to hire an engineer that wasn't "well-rounded," with excellent written and verbal communication skills, and a broader perspective on his work.

Or those wanting to do mixes of their own: http://www-pw.physics.uiowa.edu/~dag/sounds.html - the sounds page belonging to the professor who converted them to human audible... Please post mp3 conversions if you do any! Thanks

Ale

Crap.. my message got cut off.. (for some reason, it wouldn't let me do "L"+ampersand+"L" together in a post as three characters-- it cut off.

Let me try again...

---

Wow, either I'm totally spacing or we were isolated here (which I have a hard time believing, being Austin), but I don't recall GBBS... Can you recall any distinguishing features of the interface?

GBBS was a bulletin board written, if I remember right, by L[and]L Software --Lance and Lance??. It used a language called "ACOS" -- a kind of hybrid of BASIC w/o line numbers (edited in a text editor and pre-compiled) that also allowed "modules" to be written that could be loaded into memory and run in real time while the user was connected. A lot of these modules included games and stuff..

Here's an chat transcript with Lance where he talks about some new post-ACOS system I never saw...


It was basically a regular board with a door game that allowed you to challenge either a monster or another user or a progressive "dungeon" mode (basically a sequence of monster fights increasing in difficulty, death resulting in immediate logoff). Basically after a day or maybe five tops, it resulted in the sysop and ONE user taking turns killing each other to the limits of the top user's maxcallsperday.

That sounds about right. I think you could fight monsters to increase your experience points or something. I don't remember though that monopolizing the phone line would help you... I did like the "instant death" aspect of the game though...


Something to remember when we talk about how slow our modems were in those days is that we had relatively small chunks of data to deal with... a complete side of a disk was 360K tops. Even at 1200 baud, that's not THAT bad, and until Ultima 2 or so came out, very few games or applications took more than one side of an SSDD floppy. Aside from the fact that you were usually tying up the entire system at the time, the size of various Stuff made it so that 1200 baud really wasn't unbearable.

Well, for a while before Cat Fur, I was d/ling at 300 baud from AE lines-- where you could hear teh actual bits (after squeezing the phone into the cradle...) and it took about an hour anda half for a DDD (Dalton Disk Disintigrator... :)) side of a disk... and of course you KNOW your mom/sibling is picking up the phone around minute 80. Sigh.

Long live the Beagle Bros. Apple II forever.

;)
W

This is representative of robotics in general. Robots are notoriously BAD at knowing where they are in the real world, or exactly how far they have moved. That's why NASA had a lander and a rover in the Mars Pathfinder mission. The lander had a pan and scan stereo camera that could pretty accurately measure the rover's relative position from the lander (IIRC, cameras were accurate to about 5mm at 5m, but I'd have to review my notes). Without an external view, NASA would have quickly lost the rover - in one sequence of commands, the error in where the rover ended up from where it was commanded to go was as large as the distance it was supposed to move!

One way (I think, anyway) to get around this is to have many rovers all talking to each other and to the lander. Robots are good at sending relative positions, but bad at determining absolute position. So you get each robot to stay in constant contact w/2 other robots, and deterime their positions relative to itself. As long as one robot stays in constant contact with the lander, the lander can do some simple vector math and determine the positions of all the other robots! This would be cool because you can string out the robots in a long line, and you can safely move robots outside of the visual range of the lander. I wrote about it in my thesis.

There is an explanation of the Pioneer plaque (and it is a work of genius) at: http://www-pw.physics.uiowa.edu/pioneer/other/plaq ue.gif

Best wishes,
Mike.

Take a look at these files. This project is basically an example of what not to do. It's faggotted up like a twelve-year-old schoolgir's notebook, to borrow a phrase from The Onion. In particular,

• The huge block comments have these banners that are at column 1, in complete defiance of the indentation. Consequently, the indentation is not at all consistent across the code. It makes it difficult to visually see what level you are at. It makes using a folding text editor impossible.
• there are lots of comments along the lines of "// slamb was here, 4-26-02". These are things much more appropriate for a version control system (cvs annotate). They clutter up the code unnecessarily.
• the comments that are there explain nothing. For example,

  // This is the main method that Java invokes at start-up

  That should be obvious from the "public static void main (String argv[])".

• They are not in the proper form for Javadoc, Doxygen, or any other documentation generator. If you go to the trouble of putting comments at the beginning of methods in structured way, you should do so in a way that can be used to generate easily browsable documentation. See Writing Documentation Comments at Sun.
• The grammar is inconsistent and awkward. That same document gives hints on making useful documentation with grammar that does not distract.
• The code is not self-documenting. If you adhere to a consistent coding standard, like Sun's Code Conventions, you will know what a lot of stuff is without resorting to comments at all.

This Frank fellow saw these black dots on UV weather satellite images and though they were clumps of water delivered by mini comets hitting the earth. This mini comets are supposed to be house-sized fluffy snowballs, and there are a lot of problems with this theory -- why is the Moon not getting hit with these things, producing a thin water vapor atmosphere?

As pointed out, the SOHO comets are not the big honker Hale-Bopp style comets. If the Sun is bombarded with SOHO comets, maybe the Earth is being hit with Louis Frank comets after all.

I managed to get a copy of the book finally, and discovered wonderful passages such as the following on page 115:

ESB [electrical stimulation of the brain -- JAB] may evoke more elaborate responses. For example, in one of our patients, electrical stimulation of the rostral part of the internal capsule produced head turning and slow displacement of the body to either side with a well-oriented and apparently normal sequence, as if the patient were looking for something. This stimulation was repeated six times on two different days with comparable results. The interesting fact was that the patient considered the evoked activity spontaneous and always offered a reasonable explanation for it. When asked, "What are you doing?" the answers were, "I am looking for my slippers," "I heard a noise," "I am restless," and "I was looking under the bed." In this case it was difficult to ascertain whether the stimulation had evoked a movement which the patient tried to justify, or if an hallucination had been elicited which subsequently induced the patient to move and to explore the surroundings.

This passage is eerily reminiscent of a passage from Richard Dawkins' "The Extended Phenotype" chapter titled "Host Phenotypes of Parasite Genes":

"Many fascinating examples of parasites manipulating the behavior of their hosts can be given. For nematomorph larvae, who need to break out of their insect hosts and get into water where they live as adults, '...a major difficulty in the parasite's life is the return to water. It is, therefore, of particular interest that the parasite appears to affect the behavior of its host, and "encourages" it to return to water. The mechanism by which this is achieved is obscure, but there are sufficient isolated reports to certify that the parasite does influence its host, and often suicidally for the host... One of the more dramatic reports describes an infected bee flying over a pool and, when about six feet over it, diving straight into the water. Immediately on impact the gordian worm burst out and swam into the water, the maimed bee being left to die' (Croll 1966)."

The Iowa Electronic Markets are real-money futures markets in which contract payoffs depend on economic and political events such as elections. These markets are operated by faculty at the University of Iowa Tippie College of Business as part of our research and teaching mission. We invite you to join us in this mission.

You're right in that the Atanasoff-Berry Computer was the first working computer. For the record, it was made at Iowa State University, not the University of Iowa.

Probably doubtful, given the amount of willful ignorance displayed vocally and proudly on /., but if any /.ers are interested in actually learning a little bit about African history, try http://www.uiowa.edu/~africart/toc/history/giblinh istory.html for a start.

Please people, if you don't even know that "Africa" isn't a country, then you certainly aren't qualified to give opinions on Africa on a public forum.

• 16-bit Princeton architecture (64kword address space: 28K ROM, 32K RAM, 4K IO)
• Serial (RS-232) I/O for terminal
• Uber-retro audio cassette interface for mass storage

• composite video/RF out
• keyboard interface
• Parallel interface for PROM burner
• Disk interface?
  

• 16-bit Princeton architecture (64kword address space: 28K ROM, 32K RAM, 4K IO)
• Serial (RS-232) I/O for terminal
• Uber-retro audio cassette interface for mass storage

• composite video/RF out
• keyboard interface
• Parallel interface for PROM burner
• Disk interface?
  

Actually, there is an entire book about it. It's called "The Big Splash" IIRC, and it was written by a University of Iowa professor named Louis Frank. I haven't really been following this "ice comets" business much but I think I heard recently that there was some new evidence for his theory. You can read about it at:

http://smallcomets.physics.uiowa.edu/

marjine says,

the Vikings never made it past "new found land"

Depends who you ask. Some people believe that the "Vikings" (actually, a fourteenth-century band of Goths and Norwegians) made it as far inland as west central Minnesota.

Look up the Kensington Runestone. This is controversial, however; some people think it is a hoax.

ugly.

Not really that cold. But then if you consider that it has a pretty hot on board heat source (i.e. reactor), and the ONLY means for dissippating it is black body radiation (yup, its a hard vaccuum)... This means its pretty dark (i.e. cold, since its a vaccuum, the only external heat source would be incident radiation).

So, ya, its cold out in deep space ;)

You all HAVE to read this. Seriously. This is a good bit of nice dry tech specs on the Pioneer 10.

Personally, this is a very good read. I found this bit especially interesting:

The processor is completely redundant with the exception of the interface circuits. Upon command from the spacecraft, the signal processor can be switched from the main logic system to a standby redundant logic system. The function of the processor is to sequentially accumulate data on a frame basis from the seven detectors. Data are accumulated in a 24 bit register and then compressed quasi-logarithmically to 12 bits for transmission.

As the other artices say, that baby is getting quite cold. There's a year by year printout of it's tmperature on that page too.
Anyway, I just thougt I'd point this out for those interested in a little more "dry" facts on the thing other than the hoopla of it talking back (which is a feat, don't get me wrong).

A resource for punched card information:

http://www.cs.uiowa.edu/~jones/cards/index.html

• Avoid hard drives where practical--even when sitting at an idle, most buses do a good amount of vibrating/shaking.
• You can probably assemble a pretty stable power generation scheme right off the bus engine. Talk to a good mechanic about extra/beefier alternators. Run everything through a UPS (I loved watching my headlights surge during acceleration). And for god's sake, watch your gas gauge.
• Look for low/no-heat displays. Bus circulation systems are designed to be effective while the vehicle is in motion.

I started at The Univerisity of Iowa College of Engineering in 1993 and, as far as I know, the professors teaching programming courses had something like this from day one.

Incidently, an academic environment should be partially different from an industrial one. Sure, you won't get fired in industry for getting help from a collegue, but if you've never developed the basic skills needed to do your job (because you always relied on your more dedicated classmates to complete your coursework), you won't last long.

I started at The Univerisity of Iowa College of Engineering in 1993 and, as far as I know, the professors teaching programming courses had something like this from day one.

Incidently, an academic environment should be partially different from an industrial one. Sure, you won't get fired in industry for getting help from a collegue, but if you've never developed the basic skills needed to do your job (because you always relied on your more dedicated classmates to complete your coursework), you won't last long.

Only marginally more absurd than your cases 1 and 2. :)

This reminds me of the Freedows project. It's odd that, after years of hype for Freedows (an os that would run MacOS, *nix, Windows, other) programs, parallel to each other and at the same time, using one microkernel, their website has now become a pr0n gateway. Original concept here.

Some previous discussion of the trajectory issue here. The big lost opportunity for flybys was the "Grand Tour" mission. Would have had to launch in 72 or thereabouts. Bad timing -- that was just when the public felt glutted by space missions, columinating with the showy, but not demonstratively useful, Apollo project.

Yeah right, "It's always about oil." They said the same thing about Vietnam, yet the oil never materialized.

but none of the other U.S. military actions of the last few decades have been about oil--Lebanon, Somalia, Haiti, Kosovo.

Lebanon? Our entire Middle East policy is dominated by the black gold.

Kosovo? Again, not oil, but I'm sure that lead, zinc, cadmium, gold, silver, and coal mines have the interest of the US ruling class.

If memory serves, WatFor came from the University of Waterloo (Canada, not Belgium). The people who wrote it later went private and formed Watcom. Early 70s, I think.

You youngins don't know how good you have it!

There are actually quite a few uses for this type of technology (see my Master's thesis for references ). The AI community has been looking at swarm intelligence and multi-agent systems for years. NASA has sponsored research on using ant-like behavior in multiple robots to explore Mars (advantages in redundancy, system memory, command and control, etc...).

Also, check out The Swarm Development Group - you can download some software to play with alife sims, visualize really efficient search patterns, etc...

Originally IBM made equipment to deal with punched cards. However setting up a tab machine was very time consuming. Early IBM business computers were basically automated plug boards, they still used cards as i/o, but the program was quickly and easily changed. It wasn't until the 70s that mass storage started to replace punch cards. Because of this, mainframes use EBCDIC which is an enhanced version of the original punch card code, almost totally backwards compatable.

Punch cards never used ASCII, first they were in use since about 1880, long before ASCII was thought up, secondly, ASCII isn't suitable for a punch card code - if you tried to punch a card full of '7' characters, you'd end up with 400 holes on one card, which wouldn't have any structural strength. Punch cards had numbers encoded as a single hole, and everything else as one or two holes, giving a maximum of 160 holes possible on a single card. This gave a maximum of 64 different codes, so when the computer read in the card it could be very easily translated into a six bit code, a Binary Coded Decimal Interchange Code or BCDIC. Extending this to 8 bits gave EBCDIC. Here is a good description of card formats and EBCDIC.

Not a myth just a different thread of the multiverse.

See my comment regarding the Industrial Revolution 2000 years ago here.

AJ

Mayo Clinic already has a pretty cool machine for making 3-D x-ray movies. In fact, they have had it for about 20 years. They call it a dynamic spatial reconstructor. It used to take days of supercomputer processing to extract the movie from the raw data.

Computer Engineering is more structured than computer science. They approach the subject more methodically. You tend to get a more technical outlook on things. (i.e. in networking the engineers look more at numbers such as bandwidth and delay times, where the computer scientists may look more at how the overall TCP/IP structure works). Many of the upper level classes here in Computer Engineering & Computer Science overlap.

Computer Science in general is more "free and artsy" as a friend of mine said the other day. I think computer science people also get more low level experience, although they have plenty of application developing experience also.

Ideas of focus for computer engineers:Software design & designing hardware
Ideas for Computer scientists: programming/software design, graphics, designing & improving algorithms
of course those are just a few...

Have fun whatever you choose!!!!