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Wow... OK, so I ordered some stuff from Zazzle. Got a card yesterday
from the postman saying the parcel has arrived. I just picked it up and
opened it to discover... wait, WTF?
Check this out: They sent be some completely random item, unrelated to
what I actually ordered. They also sent me an invoice addressed to some
random person.
In other words, they send me somebody else's order. (!)
Gee, I wonder where *my* order went? I'm guessing to Bucharest like it
says on the invoice...
At this point, I'm stunned. Zazzle has never managed to do this before.
What the hell?
(It also looks like their printer went wrong when it printed the invoice
- lots of random random-like stripes half way down.)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Yay! The help page says to send a message to Customer Support asking for
an RMA, but the form to submit the request won't allow me to send my
message because "the email address is already in the database". Isn't
that wonderful?
(Well of COURSE my address is already in the database you dope! How do
you think I ordered this stuff if I didn't already have an account?! And
why are you asking me for an email address anyway? I'm already logged
in! Stupid web design...)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Orchid XP v8 <voi### [at] dev null> wrote:
> At this point, I'm stunned. Zazzle has never managed to do this before.
> What the hell?
Give them a break. There are just humans running Zazzle.
--
- Warp
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Warp wrote:
> Give them a break. There are just humans running Zazzle.
Well, true. I guess they just put the stuff into the wrong box, or stuck
the wrong label onto it or something. (The misprinted invoice is odd
though.)
I think I'm far *more* astonished that their system for contacting
support prohibits you from contacting them if you're already a
registered user...
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Warp wrote:
> Orchid XP v8 <voi### [at] devnull> wrote:
>> At this point, I'm stunned. Zazzle has never managed to do this before.
>> What the hell?
>
> Give them a break. There are just humans running Zazzle.
>
http://www.cracked.com/article_14990_what-monkeysphere.html
...Chambers
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Chambers wrote:
> http://www.cracked.com/article_14990_what-monkeysphere.html
Great. And now I'm REALLY depressed... :-S
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Chambers <ben### [at] pacificwebguycom> wrote:
> http://www.cracked.com/article_14990_what-monkeysphere.html
Surprisingly insightful article.
--
- Warp
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Chambers wrote:
> http://www.cracked.com/article_14990_what-monkeysphere.html
I'll second Warp. Thanks for posting that. +1
--
Darren New / San Diego, CA, USA (PST)
Helpful housekeeping hints:
Check your feather pillows for holes
before putting them in the washing machine.
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Warp wrote:
> Chambers <ben### [at] pacificwebguycom> wrote:
>> http://www.cracked.com/article_14990_what-monkeysphere.html
>
> Surprisingly insightful article.
>
I know - I totally didn't expect that, given the source :)
The main thing that people tend to forget is that every organization, no
matter what you label them ("evil corporations", anyone?), is made up of
regular old people.
Well, regular *young* people, for some of them ;)
...Chambers
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Chambers <ben### [at] pacificwebguycom> wrote:
> The main thing that people tend to forget is that every organization, no
> matter what you label them ("evil corporations", anyone?), is made up of
> regular old people.
OTOH, some of those people *are* greedy bastards who only think about
themselves and would sell their own grandmother if it was legal and there
was enough profit involved.
--
- Warp
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Warp wrote:
> OTOH, some of those people *are* greedy bastards who only think about
> themselves and would sell their own grandmother if it was legal and there
> was enough profit involved.
That's true. On the other hand, environmentalists often don't have too
much trouble making people starve or die of disease to protect the
wildlife or the mosquitoes. And I'm always amused at the "pro-life"
folks willing to murder people to save a fetus.
I think you'll get nasty selfish people everywhere. They're still people.
--
Darren New / San Diego, CA, USA (PST)
Helpful housekeeping hints:
Check your feather pillows for holes
before putting them in the washing machine.
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Darren New <dne### [at] sanrrcom> wrote:
> Warp wrote:
> > OTOH, some of those people *are* greedy bastards who only think about
> > themselves and would sell their own grandmother if it was legal and there
> > was enough profit involved.
> That's true. On the other hand, environmentalists often don't have too
> much trouble making people starve or die of disease to protect the
> wildlife or the mosquitoes. And I'm always amused at the "pro-life"
> folks willing to murder people to save a fetus.
> I think you'll get nasty selfish people everywhere. They're still people.
The problem is not really your ideology, but how extremist you are.
No matter what the ideology, if you take to an extreme, bad things will
happen.
Most ideologies have a root of rationality to them. Almost every
idology started from a good and right idea. However, when taken to
an extreme, when the ideology becomes an obsession, when the people
supporting that ideology start believing it's the *only* correct
solution to every problem, that's when things start going bad.
I have always wondered why humanity likes extremes so much. The
typical story goes like this: First someone gets an idea, good or
not, which gets widely popular, and at some point the ideology is
taken to a far extreme, causing irreparable damage. Later humanity
as a whole starts realizing the damage it caused and then try to
fix it by going to the other extreme. The problem is that it's, once
again, an extreme, and they just end up doing as much damage as the
original problem did.
Another common problem seems to be that people always need someone
to hate, someone to blame, someone to be accused of all the problems,
someone to be recipient of their extremist hatred. During the entire
history there has always been a group of people, often chosen quite
randomly, which has got its turn in being this scapegoat and receiver
of all the hatred. Sometimes the group of people is completely innocent
and the hatred completely unjust and prejudiced, sometimes the group
of people is not completely innocent, but their crimes are hugely
exaggerated through fear-mongering.
Sometimes some people would like to do something about it and try
to push the "can't we just all get along" ideology. The hippie movement
is a very good example of this. Sadly, even the hippie movement can be
and has been taken to an extreme, with all the negative repercussions.
--
- Warp
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Warp wrote:
> I have always wondered why humanity likes extremes so much.
I guess because seeing the world in black and white is easier than
reasoning about shades of grey? It's the only reason I can think of...
> Another common problem seems to be that people always need someone
> to hate, someone to blame, someone to be accused of all the problems.
I read somewhere that a scientific study showed that amoung American
social groups, there was a need for a "deviant". I forget the exact
experiment, but they found that no matter which way they put a bunch of
kids into social groups, eventually one or maybe some small number of
the kids would be singled out as "the deviant", and thereafter harrassed
and bullied. Change the social groups and the person who's the deviant
changes, but there still *is* a deviant.
The study was done in America. I forget where I read all this, but the
study made subtle hints that similar results were not found in
non-Western societies.
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Orchid XP v8 <voi### [at] devnull> wrote:
> > Another common problem seems to be that people always need someone
> > to hate, someone to blame, someone to be accused of all the problems.
> I read somewhere that a scientific study showed that amoung American
> social groups, there was a need for a "deviant". I forget the exact
> experiment, but they found that no matter which way they put a bunch of
> kids into social groups, eventually one or maybe some small number of
> the kids would be singled out as "the deviant", and thereafter harrassed
> and bullied. Change the social groups and the person who's the deviant
> changes, but there still *is* a deviant.
I'm suspecting there's something inherent in human DNA which causes this.
(Of course exceptions exist. They always exist. But they are very rare in
this case.)
--
- Warp
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>> I read somewhere that a scientific study showed that amoung American
>> social groups, there was a need for a "deviant". I forget the exact
>> experiment, but they found that no matter which way they put a bunch of
>> kids into social groups, eventually one or maybe some small number of
>> the kids would be singled out as "the deviant", and thereafter harrassed
>> and bullied. Change the social groups and the person who's the deviant
>> changes, but there still *is* a deviant.
>
> I'm suspecting there's something inherent in human DNA which causes this.
> (Of course exceptions exist. They always exist. But they are very rare in
> this case.)
The subtle hinting that this phenominon doesn't occur in some other
places [though it didn't specify WHERE] suggests that this might be
learned rather than innate. But I could be very wrong...
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Warp wrote:
> The problem is not really your ideology, but how extremist you are.
> No matter what the ideology, if you take to an extreme, bad things will
> happen.
I think we're in violent agreement here. :-)
> supporting that ideology start believing it's the *only* correct
> solution to every problem, that's when things start going bad.
That's one of the problems with monotheism. When your god is the *only*
god, you *obviously* have to do something to fix all the unbelievers.
When your gods are the Greek gods, and their gods are the Roman gods,
well, when in Rome, do as the Romans do.
> I have always wondered why humanity likes extremes so much.
Probably survival instincts. Maybe only one out of 20 snakes is
poisonous. But if you react badly to all of them, you do far less damage
to yourself than guessing wrong one out of 20 times.
> Another common problem seems to be that people always need someone
> to hate, someone to blame, someone to be accused of all the problems,
> someone to be recipient of their extremist hatred. During the entire
> history there has always been a group of people, often chosen quite
> randomly, which has got its turn in being this scapegoat and receiver
> of all the hatred. Sometimes the group of people is completely innocent
> and the hatred completely unjust and prejudiced, sometimes the group
> of people is not completely innocent, but their crimes are hugely
> exaggerated through fear-mongering.
Possibly. Certainly moreso in recent history when communication is fast
and spreads more widely. I'm trying to figure out who the (say) Greeks
or Romans hated. I'm wondering if slavery (not based on racial
characteristics, perhaps) takes the edge off such. Or if living in a
dangerous brutal world (say, aboriginies of various stripes) reduces it.
And of course, even in peacetime, people are afraid of demons, evil
spirits, stuff like that. I suspect that's the same sort of thing, to
some extent.
> Sometimes some people would like to do something about it and try
> to push the "can't we just all get along" ideology. The hippie movement
> is a very good example of this. Sadly, even the hippie movement can be
> and has been taken to an extreme, with all the negative repercussions.
Again, part of it may be that if you're trying to get along with me, and
I'm trying to take advantage of you, I'm more likely to win.
--
Darren New / San Diego, CA, USA (PST)
Helpful housekeeping hints:
Check your feather pillows for holes
before putting them in the washing machine.
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Darren New <dne### [at] sanrrcom> wrote:
> > supporting that ideology start believing it's the *only* correct
> > solution to every problem, that's when things start going bad.
> That's one of the problems with monotheism. When your god is the *only*
> god, you *obviously* have to do something to fix all the unbelievers.
Somehow I knew you would convert this into a discussion about religion
(something I really didn't want to do, as I was talking in a more general
manner about human nature, independently of indivudal ideologies), but
I'm going to pass on that troll this time, sorry. I'll let others take
that bait if they want.
--
- Warp
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Warp wrote:
> Somehow I knew you would convert this into a discussion about religion
Hmmm... Pull one line out of a whole post, and call it a troll? Very good.
--
Darren New / San Diego, CA, USA (PST)
Helpful housekeeping hints:
Check your feather pillows for holes
before putting them in the washing machine.
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On Sun, 13 Jul 2008 16:25:41 -0400, Warp wrote:
> Darren New <dne### [at] sanrrcom> wrote:
>> > supporting that ideology start believing it's the *only* correct
>> > solution to every problem, that's when things start going bad.
>
>> That's one of the problems with monotheism. When your god is the *only*
>> god, you *obviously* have to do something to fix all the unbelievers.
>
> Somehow I knew you would convert this into a discussion about religion
> (something I really didn't want to do, as I was talking in a more
> general manner about human nature, independently of indivudal
> ideologies),
Well, it seems to me that this is one of the most common applications of
applying a single "good vs. evil" ideology to the world. It's really
easy to follow a religion (I'd go that far rather than just limiting it
to monotheism, myself) if the boundaries between good and evil are really
clear cut with no room for "shades of grey".
Jim
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Jim Henderson wrote:
> Well, it seems to me that this is one of the most common applications of
> applying a single "good vs. evil" ideology to the world.
I'm also amused that he quoted the monotheism sentence as an attack on
religion, rather than the Greek gods, the demons and spirits, or other
religion-based bits. I was actually thinking at least as much the modern
Chinese government banning Christianity as well as Fallun Gong (sp?) as
an "other" kind of thing as I was the Spanish conquistadors.
--
Darren New / San Diego, CA, USA (PST)
Helpful housekeeping hints:
Check your feather pillows for holes
before putting them in the washing machine.
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Warp wrote:
> Somehow I knew you would convert this into a discussion about religion
By the way... Sorry if I annoyed you with that. It wasn't my intention.
--
Darren New / San Diego, CA, USA (PST)
Helpful housekeeping hints:
Check your feather pillows for holes
before putting them in the washing machine.
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On Sun, 13 Jul 2008 19:03:15 -0700, Darren New wrote:
> Jim Henderson wrote:
>> Well, it seems to me that this is one of the most common applications
>> of applying a single "good vs. evil" ideology to the world.
>
> I'm also amused that he quoted the monotheism sentence as an attack on
> religion, rather than the Greek gods, the demons and spirits, or other
> religion-based bits. I was actually thinking at least as much the modern
> Chinese government banning Christianity as well as Fallun Gong (sp?) as
> an "other" kind of thing as I was the Spanish conquistadors.
I found it interesting as well - I guess it's easy to take offense at
what you're not familiar with, but not to at other things.
Kinda reminds me of Isaac Hayes - he was fine with all the allusions in
South Park to the problems with religions he didn't believe in, but once
they went after Scientology, his tolerance was limited. It's always
easier to make fun of others than it is yourself, I guess.
Jim
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>> At this point, I'm stunned. Zazzle has never managed to do this before.
>> What the hell?
>
> Give them a break. There are just humans running Zazzle.
Exactly, which is why they should have systems in place to stop mistakes,
which will happen, getting outside their company. But I guess that costs
money so they make some compromise.
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On Sun, 13 Jul 2008 13:18:15 -0700, Darren New <dne### [at] sanrrcom> wrote:
>That's one of the problems with monotheism. When your god is the *only*
>god, you *obviously* have to do something to fix all the unbelievers.
>When your gods are the Greek gods, and their gods are the Roman gods,
>well, when in Rome, do as the Romans do.
<Nitpicking>
The Romans pretty much had the same gods as the Greeks, the names were changed
to protect the innocent. :)
Also when the Romans were in power Greece was subjective to them and I would
think that they would talk about Jupiter or Jove rather than Zeus to Romans out
of respect.
</Nitpicking>
But I agree with you "One god to rule them all" :)
--
Regards
Stephen
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scott wrote:
>
> Exactly, which is why they should have systems in place to stop
> mistakes, which will happen, getting outside their company. But I guess
> that costs money so they make some compromise.
>
Those systems are made by humans, so they are always compromises.
Or why do you think software has bugs and holes? :)
--
Eero "Aero" Ahonen
http://www.zbxt.net
aer### [at] removethiszbxtnetinvalid
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And lo on Sun, 13 Jul 2008 19:49:33 +0100, Orchid XP v8 <voi### [at] devnull>
did spake, saying:
> Warp wrote:
>
>> I have always wondered why humanity likes extremes so much.
>
> I guess because seeing the world in black and white is easier than
> reasoning about shades of grey? It's the only reason I can think of...
On that note I recall reading somewhere a suggestion that it's caused by
us thinking in binary - If A = Good then !A = Bad; such that if we'v
e been
doing A a lot because we think it's good and it turns out not to be we
automatically turn to !A, because now that must be good :-)
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
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Phil Cook <phi### [at] nospamrocainfreeservecouk> wrote:
> On that note I recall reading somewhere a suggestion that it's caused by
> us thinking in binary - If A = Good then !A = Bad; such that if we've been
> doing A a lot because we think it's good and it turns out not to be we
> automatically turn to !A, because now that must be good :-)
Actually we think in ternary. The third value is "I don't care", which
sometimes also causes problems when taken to an extreme.
--
- Warp
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Eero Ahonen <aer### [at] removethiszbxtnetinvalid> wrote:
> Or why do you think software has bugs and holes? :)
There are small critters inside computers which dig these holes and
are infested with these bugs, parasites and other diseases. Where do you
think "computer virus" comes from?
--
- Warp
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Warp wrote:
> There are small critters inside computers which dig these holes and
> are infested with these bugs, parasites and other diseases. Where do you
> think "computer virus" comes from?
So ... does that explain why when I sneezed on my keyboard and monitor,
my system started belching out loads and loads of ads for fake rolex
watches and cialis?
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Mike Raiford <mra### [at] hotmailcom> wrote:
> Warp wrote:
> > There are small critters inside computers which dig these holes and
> > are infested with these bugs, parasites and other diseases. Where do you
> > think "computer virus" comes from?
> So ... does that explain why when I sneezed on my keyboard and monitor,
> my system started belching out loads and loads of ads for fake rolex
> watches and cialis?
No, that's just those damned haxorz hacking at your computer.
--
- Warp
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Stephen wrote:
> The Romans pretty much had the same gods as the Greeks, the names were changed
> to protect the innocent. :)
Well, yes, naturally. All the more reason to start wars over it. ;-)
> Also when the Romans were in power Greece was subjective to them and I would
> think that they would talk about Jupiter or Jove rather than Zeus to Romans out
> of respect.
I wasn't sure that was the case. My ancient history isn't too good. :-)
--
Darren New / San Diego, CA, USA (PST)
Helpful housekeeping hints:
Check your feather pillows for holes
before putting them in the washing machine.
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>> Exactly, which is why they should have systems in place to stop mistakes,
>> which will happen, getting outside their company. But I guess that costs
>> money so they make some compromise.
>>
>
> Those systems are made by humans, so they are always compromises.
Of course, but a group of clever humans can design a system that prevents
all the common mistakes from getting out.
> Or why do you think software has bugs and holes? :)
Because usually it's not worth the effort preventing them getting out? It's
not because it's impossible. Compare software released for home/office use
with software released for running cars, or factories, or power stations, or
planes, or space ships.
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And lo on Mon, 14 Jul 2008 17:18:06 +0100, Warp <war### [at] tagpovrayorg> di
d
spake, saying:
> Phil Cook <phi### [at] nospamrocainfreeservecouk> wrote:
>> On that note I recall reading somewhere a suggestion that it's caused
by
>> us thinking in binary - If A = Good then !A = Bad; such that if w
e've
>> been
>> doing A a lot because we think it's good and it turns out not to be w
e
>> automatically turn to !A, because now that must be good :-)
>
> Actually we think in ternary. The third value is "I don't care", whi
ch
> sometimes also causes problems when taken to an extreme.
I don't think you'll find anyone who's that neutral.
To use my hypothetical hat-wearing law; there will be those who think it
's
bad and those who think it's good. It may be possible to argue that thos
e
who say "I don't care" have no strong feelings either way, but I would
expect a modifier such as "I don't care, but I think it's a bit stupid"
or
"I don't care, but it certainly makes everyone look smarter".
--
Phil Cook
--
I once tried to be apathetic, but I just couldn't be bothered
http://flipc.blogspot.com
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On Mon, 14 Jul 2008 11:20:31 -0700, Darren New <dne### [at] sanrrcom> wrote:
>Stephen wrote:
>> The Romans pretty much had the same gods as the Greeks, the names were changed
>> to protect the innocent. :)
>
>Well, yes, naturally. All the more reason to start wars over it. ;-)
>
A very good point.
>> Also when the Romans were in power Greece was subjective to them and I would
>> think that they would talk about Jupiter or Jove rather than Zeus to Romans out
>> of respect.
>
>I wasn't sure that was the case. My ancient history isn't too good. :-)
I guessed :-)
--
Regards
Stephen
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scott wrote:
>> Or why do you think software has bugs and holes? :)
>
> Because usually it's not worth the effort preventing them getting out?
> It's not because it's impossible. Compare software released for
> home/office use with software released for running cars, or factories,
> or power stations, or planes, or space ships.
>
You don't think there's bugs in these? ;) NASA's space shuttle is an
exception. I read an article somewhere that before any program change is
made, there are meetings upon meetings. I'm sure there are glitches in
the firmware of cars, you probably don't notice, or think its something
mechanically wrong.
I can tell you automated manufacturing equipment does, in fact, have
bugs. I've seen serious software errors in the FIRMWARE of servo
drives*. Some of which are used in such applications as airplanes. No
worries, though, most of the bugs can be worked around and the main PID
loop seems to do what its supposed to. Mostly. I've seen bearings in our
equipment crushed because a drive didn't stop pumping current into the
motor when it ran against a hard stop. Entertaining -- it ramped the
current up high enough to fry the motor coils. Oops. I've personally
stripped toothed belts bare because of a software error. Had I had the
blade running (I never do in testing, I always have the blade removed) I
would have run a saw blade into a steel I-Beam. I can't even imagine the
consequences for that. I don't think it would be pretty.
There's a reason equipment has a hard-wired emergency stop button that
cuts the power to the drives and motors.... Oh, and most avionics have
direct linkage to the controls. The drives AFAIK are only used in
autopilot, so that can be disengaged if something goes awry.
* For the curious: A servo drive is generally a signal generator and
amplifier used for driving a servo motor. The signal is controlled by a
feedback loop (PID - Andrew should know what this means, Proportional,
Integral, Derivative ) the general case is the greater the error, the
more current fed to the motor. As the error decreases, so too does the
current (P), the motor will eventually settle into position smoothly
(I,D). Thankfully, the heavy calculus lifting is done in the drive's
firmware all the software has to do is give it the factors found from
running a tuning routine, then feed it position, velocity or torque
(depending on your goals) It will then use the PID loop to achieve the
desired value. Obviously there are limits. The drive may allow a few
counts either way on position to be "in position" it may allow some
slack in velocity, or may allow some difference in applied torque. There
is of course a maximum current the motor can handle for short bursts. A
maximum amount of error for a certain amount of time the drive will
tolerate before it gives up, powers down the motor and reports a fault.
The drive described above didn't do this. The error was right below
maximum, but far enough to pump the full amount of current into the motor.
I've had some fun with servo drives in a "lab" setting. Usually the
motor will have a toothed wheel on it, so I can see what its doing. Once
the motor is in position, if the drive is still on, you can grab the
wheel and turn it, and depending on the tuning parameters it can have a
very soft feel, or hard feel. It reacts almost like a rubber band or a
spring. The more you turn it out of position, the more it fights you.
Even small motors have an amazing amount of torque. With low enough
current limits, you can turn the motor past the maximum position error,
and have it "break free" You can also grab it while its turning, hold it
and feel it stop trying once the error gets past a certain amount.
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>> Because usually it's not worth the effort preventing them getting out?
>> It's not because it's impossible. Compare software released for
>> home/office use with software released for running cars, or factories, or
>> power stations, or planes, or space ships.
>>
>
> You don't think there's bugs in these? ;)
Of course there are, but far less than in desktop software. My point was
that depending how much effort you want to put in to it, you either end up
with software like Microsoft, software like Nasa, or somewhere inbetween.
> I read an article somewhere that before any program change is made, there
> are meetings upon meetings.
I think that happens for a lot of software development, not just in space
shuttles.
> I'm sure there are glitches in the firmware of cars, you probably don't
> notice, or think its something mechanically wrong.
It's extremely unusual though, almost unheard of, for there to be any
noticeable glitch in the core software running a car. It's simply because
the consequences are so great, that the effort is put in to ensure that no
glitches ever can occur. Especially nowadays with all the stability, engine
and other control stuff run by software, it would be a total disaster for
any company if their cars suddenly did something stupid under certain
conditions.
> I've seen bearings in our equipment crushed because a drive didn't stop
> pumping current into the motor when it ran against a hard stop.
I saw a solid steel drive bar approx 10cm diameter sheared in two by a
motor, it was meant to be driving a machine to compress paper, but it got
jammed and for some reason the controller didn't stop the motor but kept
giving it more power.
> Entertaining -- it ramped the current up high enough to fry the motor
> coils. Oops. I've personally stripped toothed belts bare because of a
> software error.
But if you knew your software was to control something like a car or plane
with people in it, you would have course checked and tested your software
more thoroughly. That's my original point, ditto with Andrew's order, if
they really cared enough they would have systems in place to make sure that
incorrect orders could not be delivered.
> Oh, and most avionics have direct linkage to the controls. The drives
> AFAIK are only used in autopilot, so that can be disengaged if something
> goes awry.
Maybe on very small civilian aircraft, but on any passenger carrying jet or
military jet the control system is totally electronic with no mechanical
linkages. I suspect it would be near impossible for a person to manually
control most planes mechanically, both because of the high forces needed,
and the lack of an electronic controller to help keep things stable.
But usually there are 4 totally separate controllers, so they do have a high
degree of redundancy.
> Thankfully, the heavy calculus lifting is done in the drive's firmware all
> the software has to do is give it the factors found from running a tuning
> routine, then feed it position, velocity or torque (depending on your
> goals) It will then use the PID loop to achieve the desired value.
Reminds me of doing PID control loops at University, our lecturer had this
huge example about 2 metres high with a beefy motor controlling this mass on
cables around a pulley. He spent almost the whole lecture explaining the
theory (where most people had fallen asleep due to the horrendous calculus
involved), and at the end did the demo. He had set it up to get from point
A to point B in the shortest time with something like 5% overshoot.
Everyone was suddenly paying attention now as he was about to switch it on,
and then as he flicked the switch, the mass moved extremely quickly to point
B, past point B, kept accelerating and smashed off the end of the demo.
Everybody laughed.
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On Tue, 15 Jul 2008 07:36:10 -0500, Mike Raiford <mra### [at] hotmailcom> wrote:
>(PID - Andrew should know what this means, Proportional,
>Integral, Derivative )
Thank you I read it as "Piping & Instrumentation Diagram"
--
Regards
Stephen
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scott wrote:
> Of course there are, but far less than in desktop software. My point
> was that depending how much effort you want to put in to it, you either
> end up with software like Microsoft, software like Nasa, or somewhere
> inbetween.
NASA?
Aren't they those guys who tried to launch a rocket with a faulty O-ring?
Mmm, I guess it's not only M$ that sometimes rushes things due to
"launch shedules".
(You see what I did there?)
>> I'm sure there are glitches in the firmware of cars, you probably
>> don't notice, or think its something mechanically wrong.
>
> It's extremely unusual though, almost unheard of, for there to be any
> noticeable glitch in the core software running a car. It's simply
> because the consequences are so great, that the effort is put in to
> ensure that no glitches ever can occur. Especially nowadays with all
> the stability, engine and other control stuff run by software, it would
> be a total disaster for any company if their cars suddenly did something
> stupid under certain conditions.
Depends on how "stupid". I hear there's a car (I forget which) that has
a design fault so anybody who knows the "trick" can open the boot with
their bare hands even when it's locked - yet the manufacturers
repeatedly refused to admit that anything was wrong...
> I saw a solid steel drive bar approx 10cm diameter sheared in two by a
> motor, it was meant to be driving a machine to compress paper, but it
> got jammed and for some reason the controller didn't stop the motor but
> kept giving it more power.
I saw a machine that can casually snip through 30 mm spring steel the
way a hole punch cuts through tissue paper. The operator commented
"don't put your fingers in this". (!!)
> But if you knew your software was to control something like a car or
> plane with people in it, you would have course checked and tested your
> software more thoroughly. That's my original point, ditto with Andrew's
> order, if they really cared enough they would have systems in place to
> make sure that incorrect orders could not be delivered.
This is what it all comes down to. You can make things as reliable as
you want - it's merely a question of how much money you want to spend
doing it. ;-)
> But usually there are 4 totally separate controllers, so they do have a
> high degree of redundancy.
...I also saw a black-box flight recorder yesterday...
(It was orange.)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Orchid XP v8 <voi### [at] devnull> wrote:
> NASA?
> Aren't they those guys who tried to launch a rocket with a faulty O-ring?
Take two programs of comparable size made in Microsoft and in NASA,
and compare the total amount of bugs found during testing. The former will
have in the order of thousands, while the latter will have something
like 10.
And the latter while never exceeding budgets nor deadlines.
--
- Warp
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scott wrote:
>> I read an article somewhere that before any program change is made,
>> there are meetings upon meetings.
>
> I think that happens for a lot of software development, not just in
> space shuttles.
>
Some, but definitely not all. Many places a small fix-up may not need a
day's worth of meetings, but with the shuttle, not a single line of code
can be changed.
I think this is the article:
http://findarticles.com/p/articles/mi_m0ISJ/is_n1_v33/ai_15103437
>> I'm sure there are glitches in the firmware of cars, you probably
>> don't notice, or think its something mechanically wrong.
>
> It's extremely unusual though, almost unheard of, for there to be any
> noticeable glitch in the core software running a car. It's simply
> because the consequences are so great, that the effort is put in to
> ensure that no glitches ever can occur. Especially nowadays with all
> the stability, engine and other control stuff run by software, it would
> be a total disaster for any company if their cars suddenly did something
> stupid under certain conditions.
I seem to remember a glitch in the ABS system for certain GM vehicles
many years ago.
>> Entertaining -- it ramped the current up high enough to fry the motor
>> coils. Oops. I've personally stripped toothed belts bare because of a
>> software error.
>
> But if you knew your software was to control something like a car or
> plane with people in it, you would have course checked and tested your
> software more thoroughly. That's my original point, ditto with Andrew's
> order, if they really cared enough they would have systems in place to
> make sure that incorrect orders could not be delivered.
In this case it didn't make it to production until it was corrected. We
really didn't want our customers to have to constantly replace bearings
and motors. ;)
>> Oh, and most avionics have direct linkage to the controls. The drives
>> AFAIK are only used in autopilot, so that can be disengaged if
>> something goes awry.
>
> Maybe on very small civilian aircraft, but on any passenger carrying jet
> or military jet the control system is totally electronic with no
> mechanical linkages. I suspect it would be near impossible for a person
> to manually control most planes mechanically, both because of the high
> forces needed, and the lack of an electronic controller to help keep
> things stable.
>
> But usually there are 4 totally separate controllers, so they do have a
> high degree of redundancy.
Ah, I figured the avionics linkages would be hydraulic, not computer
controlled.
> about to switch it on, and then as he flicked the switch, the mass moved
> extremely quickly to point B, past point B, kept accelerating and
> smashed off the end of the demo. Everybody laughed.
Heh. Ouch...
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"Orchid XP v8" <voi### [at] devnull> wrote in message
news:487cc8b8@news.povray.org...
> Mmm, I guess it's not only M$ that sometimes rushes things due to
> "launch shedules".
>
> (You see what I did there?)
Hint: pointing out your own puns makes them irritating more than funny
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Gail Shaw wrote:
> Hint: pointing out your own puns makes them irritating more than funny
Question: Are *my* puns even funny in the first place?
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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>> NASA?
>
>> Aren't they those guys who tried to launch a rocket with a faulty O-ring?
>
> Take two programs of comparable size made in Microsoft and in NASA,
> and compare the total amount of bugs found during testing. The former will
> have in the order of thousands, while the latter will have something
> like 10.
>
> And the latter while never exceeding budgets nor deadlines.
A NASA rocket exploding is something like an M$ product having a severe
security vulnerability.
So far, NASA has had, what, 2 major incidents like this? In its entire
history?
(...I'm sure you see where I'm going with this...)
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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Orchid XP v8 wrote:
> Gail Shaw wrote:
>
>> Hint: pointing out your own puns makes them irritating more than funny
>
> Question: Are *my* puns even funny in the first place?
>
It is possible ...
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"Orchid XP v8" <voi### [at] devnull> wrote in message
news:487ccf56$1@news.povray.org...
> Gail Shaw wrote:
>
> > Hint: pointing out your own puns makes them irritating more than funny
>
> Question: Are *my* puns even funny in the first place?
>
Some are, some I would miss. That's how puns are supposed to be
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Stephen wrote:
> On Tue, 15 Jul 2008 07:36:10 -0500, Mike Raiford <mra### [at] hotmailcom> wrote:
>
>> (PID - Andrew should know what this means, Proportional,
>> Integral, Derivative )
>
> Thank you I read it as "Piping & Instrumentation Diagram"
...and I read it as Prolapsed Intervertebral Disc
John
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Orchid XP v8 wrote:
> A NASA rocket exploding is something like an M$ product having a severe
> security vulnerability.
I don't think that's a fair comparison .. Sure, a security vulnerability
is a headache, but it did just kill the crew, and spread flaming debris
across half of Texas ...
> So far, NASA has had, what, 2 major incidents like this? In its entire
> history?
>
> (...I'm sure you see where I'm going with this...)
>
Didn't the ESA lose a mars probe because of a program error?
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Doctor John wrote:
> Stephen wrote:
>> On Tue, 15 Jul 2008 07:36:10 -0500, Mike Raiford <mra### [at] hotmailcom> wrote:
>>
>>> (PID - Andrew should know what this means, Proportional,
>>> Integral, Derivative )
>> Thank you I read it as "Piping & Instrumentation Diagram"
>
> ...and I read it as Prolapsed Intervertebral Disc
>
> John
At least no one has read it as "Personal Integrity Device" ...
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>> A NASA rocket exploding is something like an M$ product having a
>> severe security vulnerability.
>
> I don't think that's a fair comparison .. Sure, a security vulnerability
> is a headache, but it did just kill the crew, and spread flaming debris
> across half of Texas ...
...which is why software bugs are "acceptable", and safety issues
aren't. ;-)
But I think it *is* a fair comparison: M$ Windoze is not capable of
killing anybody [usually], so a severe security issue is just about the
most catastrophic kind of problem it can experience.
> Didn't the ESA lose a mars probe because of a program error?
Possibly.
Space is a pretty harsh environment, so there's a whole array of
possible malfunctions that could end a mission - broken motors or
sensors, compromised computer hardware, corrupted RAM portions, or
conceivably simple programmer error. The last one would seem one of the
easiest classes of fault to prevent, but sure, one might have slipped
though somewhere...
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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>> (PID - Andrew should know what this means, Proportional,
>> Integral, Derivative )
Andrew did *not* know what it means. I was assuming Process ID...
--
http://blog.orphi.me.uk/
http://www.zazzle.com/MathematicalOrchid*
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