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Pendulum Clock with Atomic Precision
u19925 writes "Now you can get atomic clock precision out of your grandma pendulum clocks. Here is how it works: There is a camcorder fitted inside the clock which monitors the pendulum swing. It has an atomic clock signal receiver. It compares the pendulum swings with the atomic signal hearbeat. The camcorder also has an arm. If the pendulum clock drifts, then it uses its arm to push or pull the pendulum to make correction." It's not an April Fool's joke, but it is rather impractical.
Now if we could just invent something that would push or pull Grandma when she's not regular enough...
Huh?
It would be nice if the submitter placed a working link to the article in question.
Why not just control the swing with a couple of magnets mounted at the ends of the pendulum's arc? It would surely be cheaper and easier to maintain than a camera and mechanical arm ;-)
Code, Hardware, stuff like that.
Editors forgot how to insert links.
Any "HTML Programmers" care to help?
heres a revised version of the article:
Now you can get atomic clock precision out of your grandma pendulum clocks. Here is how it works: There is a camcorder fitted inside the clock which monitors the pendulum swing. It has an atomic clock signal receiver. It compares the pendulum swings with the atomic signal hearbeat. The camcorder also has an arm. If the pendulum clock drifts, then it uses its arm to push or pull the pendulum to make correction. " It's not an April Fool's joke, but it is rather impractical.
"Now you can get A HREF="http://www.newscientist.com/news/news.jsp?id =ns99993549">atomic clock precision out of your grandma pendulum clocks.
Sigh. I'd love to get a href, but where would I put it?
how about that hyperlink :\
BilldaCat
Is that broken link an april fools joke? Obviously CowboyNeal didnt click the link because you cant!
Why incur the cost and complexity of designing this system with a camera?
Couldn't a simple cheap magnetic sensor and some sort of magnets or motor be cheaper, more precise, and a hell of a lot easier to design??
Is this real science, or the results of this year's Rube Goldberg contest?
Wow.
Maw! Fire up the karma burner!
Not an April Fool's link, but it is rather impractical.
Try this
Infuriate left and right
My plan was to put a magnet on the pendulum and then put the regulation mechanism on the reverse. This would measure each swing of the pendulum from the emf induced in a coil on the back of the clock. This would also be used to advance or retard the pendulum if necessary.
Looking for an Information Security student project suggestion?
Try http://dotcrimeManifesto.com/
...is there to prevent posters from making glaring errors in their submissions.
Maybe the editors should get one of those too. It's pretty handy for us peons who make mistakes all the time...
Amazon has patented hyperlinking, so from now on ... you'll have to form your own links....
Perhaps Slashdot needs an atomically-precise HTML checker to catch those pesky "a href" tags.
stuff |
For more information on pendulum clocks, check out A HREF="http://science.howstuffworks.com/clock.htm"> this site :P
umm, I don't think it was the editors that wrote the post. They just posted it. I believe it has always been there policy to not change the original content of the person who submitted. Of course, a link where they posted there comment would have been nice.
The Kruger Dunning explains most post on
Wouldn't the latency of the net connection/camera/lever defeat the whole purpose of atomic precision? I mean, anyone can just reset thier clock once and a while to the "technical" standard time. Is this really accurate?
We're only gonna die from our own arrogance, that's why we might as well take our time...
Simply nudge the clock base vertically (pikc a corner/side) as required, by a small system of active mounts, that sense the pendulum's momentum and urge correction? Banging on the weight as it swings seems a bit counter-productive.
Now we can replace all of throw away all of the atomic clocks and replace them with this. ;)
Funny how all the people come out of the woodwork to chime in on an obvious problem, as if that's all they have to say, or at least can think about. Of course they made a mistake, but do we need 30 people (it's still early in the life of the commenting on the article) to regurgitate the same error pointed out?
It's 1/10 second precision that get synced daily to an atomic clock - a pendulum clock with "atomic precision" doesn't even pass the sniff test
Accept no substitutes.
I don't need no instructions to know how to rock!!!!
the editors just score: -1, troll your posts. they'd rather sweep the problems under the carpet than make an honest effort into improving things around here.
face it, this site is shit and it's editors and owners are shit as well.
Pfft, as if anyone who reads slashdot is looking for websites that don't suck. I think you worry for nothing.
You never even thought of it until just now.
C'mon, admit it.
I don't need no instructions to know how to rock!!!!
This time, I actually read the article, and it's insanely funny!
I'm not sure why. Probably because it's British.
I'm a self professed 'gadget junkie' and love playing around with robots and stuff, but this idea is just, well lame. And irrelevant. As if you are going to notice that your clock is out by 1/100 of a second. I don't know why you'd even bother. I know this sounds negative et al, but zzZZZzz.
Everyone thinks of changing the world, but no one thinks of changing himself. -- Leo Tolstoy
The second rule of Slashdot is: WE DON'T TALK about Slashdot on Slashdot!
The mods/editors will rape anyone that tries. But where else in the world can you post anything at all and at most risk being auto-banned for a day or two?
Amen brother
I know that's a rather short reply for such an essay. I'm not sure why the editorialism of Slashdot is as low as it is unless the editors are secretly developing a software package for VA Software (or whatever their name is now) 99% of the day and spend only a minute or two to approve an article and go back to developing code, or relaxing and eating pizza.
Looks like one of the editors decided to 'offtopic' everyone in this thread. Typical.
Preach on brotha. Slashdot is full of old news that can be had from other places days in advance. There's that, and you don't have to hear about stupid fucking annoying cowboy neal, or listen to michael's liberal whining.
Brilliance.
Yes.
As an AC with a posting limit of 10, I understand. Basically the only satisfactury alternatives is news sites that have good journalistic standards without a posting capability or posting with moderation (what Slashdot does is more a scoring filter than, moderating as Usenet or private groups practice it, for example).
About 20 years ago - only they used the mechanism from a quartz clock.
It's Christmas everyday with BitTorrent.
Because slashdot wants a competition on shit?
I solemnly swear to take up the post of trolling every thread from now on with fake April Fools posts to prevent that cockmonger Taco from fucking up Aprils Fools 2004 the same way he did for 2003. So remember this day, the start of a trolling revolution!
Doesn't anyone read the friggin articles?
Nowhere in the article are the words 'camcorder', 'grandma', 'arm', etc.
It wasn't designed to fit into a grandmother clock and it certainly doesn't use a camcorder. It uses an infared sensor to sense pendulum location and a 'piston' to modify pendulum swing, and it is being used to automate maintenance on large clocks in churches, etc. It can also set the clock ahead and back an hour for daylight savings time.
Gotta be the worst case of can't be bothered to RTFA I've ever seen.
Now, anyone who thinks it would be better to replace the clocks in Big Ben with some modern electronic thing... well... probably ought to be shot. This doesn't seem like a bad way to get those big clocks to operate a good long time without human intervention.
Sweet! Now the 'tick-tock-tick' my grandma hears every day of her life ominously counting down to her impending death can be atomically accurate! Thanks Slashdot!
Our clocks are perfection... Resistance is futile.
Karma: The shiznight, mostly because I am the Drizzle.
I feel that some informed comments are required for this topic. I am a clockmaker, yes I work on 200 year old clocks all the time; and I have to say that this is a really neat merging of modern and antique technology.
The clocks that are being regulated are tower clocks, they are observed by hundreds if not thousands of people a day. It would be nice to know that they are on time. It would also be a crime to rip out the old pendulum movement and replace them with an electric movement. Another feature is that the old antique system can run for several days in the event of a power failure, it just won't be quite as accurate.
The movements in these clocks are heavy cast iron units with large gears and very heavy pendulums. Using a magnet system to attempt to influence the timing rate would probably prove ineffective. However using some sort of system to raise or lower the pendulum by just a couple of millimeters will affect the timing rate by several seconds a day.
These clocks used to be wound once a week by hand and the time would have been reset at that time. These days most of these clocks have been converted to an automatic winding system, thus they see much less hands on maintenance, automatic systems for regulating the clock become much more attractive.
As a side note, the tower clock in London, commonly known as "Big Ben" ("Big Ben" is really the name of the bell that is used to count the hours) is regulated by adding or removing one or two old English Pennies, the one that were about the size of an old American Silver Dollar. The clock is regulated to be as on time as possible on the Queens Birthday and on New Years Eve.
Going even further afield some of you might get a kick out of the elaborate astronomical clocks that were designed in the 1800's. These were astonishing pieces of engineering that have been known to take an astronomer to figure out all of the settings required to set the clock.
I guess my passion for my vocation is showing, I hope that I was able to add something of interest.
Chronos
Uhh, it may just be me, but isn't the atomic receiver the one doing the time telling? I mean, you're using a clock to run the pendulum, whereas the order used to be reversed. (Pendulum ran the clock)
Does that seem really frivilous to you too? This barely fits under "Stuff that matters"
From the article:
The piston will gradually stop the pendulum over 20 swings or so, avoiding any sudden forces. Then, 11 hours later, when it will be 1 pm British Summer Time, the piston will gently set it ticking again
So if lightning strikes the clock at 8:00 am, it will be stopped at 1:00, and no one will be able get their time machine back to the future...
I know lots of things. Most of them are wrong.
You reminded me of this old April Fools joke: http://www.jonnypage.ca/archives/000134.html --
Nor is it impractical. As the article points out, it is intended for very old clocks that can have very delicate mechanisms. By automating tasks like daylight savings, they can make sure changes are made gently over a longer period and that there's less opportunity for ham-fists to break things.
TFA also states that because we're talking about historic clocks, they can't go drilling holes into them and bolting stuff on. Hence the Rube Goldberg nature of these non-invasive mods.
Xix.
"Everything is adjustable, provided you have the right tools"
Danny Hillis designed the Clock of the Long Now to keep time accurate to the second for 10,000 years, and it's completely mechanical.
Most ( if not all ) grandfather clocks I've seen don't have a hand for seconds so how are you going to know you've lost a second of time? Stare at the clock for an hour? Have fun!
I read this as Pentium Clock with Atomic Precision
So I'm thinking to myself, why would someone make a clock with a Pentium in it? What would be the point? Some kind of wi-fi enabled clock that turns on the wi-fi enabled coffee machine in the morning?
Then my brain woke up....
Huh?
So basicly you can make a normal clock as accurate as an atomic clock by putting an atomic clock inside it... hmm...
cat
ummm, nice try buddy.
I'm the inventor of the "you fail it" line. And by fucking up the sentence with that stupid addition you put on it doesn't work. I afraid...
YOU FAIL IT!!
In answer to the people who suggest (electro)magnets, a design to do just this was published long ago, before the 1993 archive start, in dead tree Scientific American. Assuming the pendulum weight is cast iron, it is perfectly practical to use a magnet. As I remember it, the magnet goes on the dead center line below the pendulum bob. Depending on where in the cycle it is turned on briefly, it will accelerate or decelerate the pendulum very slightly. I guess with some clocks if you made the magnet big enough, it could be used to decelerate the pendulum very slowly to a complete stop allowing the Daylight Saving adjustment, and the use of a second magnet to one side could then enable a restart. Potentially less invasive than an arm that prods the pendulum, which seems extremely Heath Robinson or Wallace and Gromit to me.
Panurge has posted for the last time. Thanks for the positive moderations.
This is slightly off topic but related.
I have a Western Union Clock I inhereted from my grandfather.
Whats a Western Union Clock?
It's a big round self-winding pendulum clock. Apparently they were ordered from western union. Someone would come install this clock on the wall with a single wire coming from the back the wire would supply power for the winding mechanism and (This is the cool/relevant part) every hour on the hour a signal would come through the wire and the minute hand on the clock would jump to 12 giving a fairly accurate clock.
What I've wanted to do for a while if find a way to get my computer to send the hour signal to the clock so it would have atomi "accuracy" at least on the hour
We got a camcorder bitch slapping a poor grandma into sync... what has our world come to!!
The Japanese do it any time a quake hits Yokohama. Yokohama's Landmark Tower, 70 stories, has a fully suspended base, computer controlled, that reacts to earthquakes by countering movements in order to offset jolts that would bring ordinary buildings down. Why raise the bridge, when you can just as easily lower the water.
If an active base works for something this large, it can be scaled down, I'm sure.
not only that, it has to be marked as not an april fools joke
I meam, really. A fucking pendulum. Get a fucking life. Christ in a bottle. A [i]pendulum[/i]. Think about it. There's a fucking war on and you're worried about a penduleum. Sorry, but this says a lot.
If you're sure it will be hard, or it can't be done without a fight, you are likely to be correct in the end. In the mean time, someone else will succeed where you fail.
The description shoud have been:
"Now you can make an atomic clock out of a grandma clock and another atomic clock"
Woo
Camcorder - where on earth did he get that from?! Did the guy that submitted that actaully read the article he was submitting?! It doesn't mention that in the article - mainly because it would be a stupid idea. That's maxiumum overkill if I've ever heard of it. That would be like using a camcorder to 'look' and see if the fridge door is shut!
And why use a piston to change the swing? What's wrong with an electromagnet which wouldn't need to actually touch the pendlum?
Nick...
In Soviet Russia, the clocks set YOU!
Seems like a quartz would do better than that!
Overengineered.
Synchronizing a clock with another one is hardly new. Any raido-controlled clock does it. And it does not give you a "Pendulum Clock with Atomic Precision" at all. It gives you a slaved pendulum that is still pretty imprecise but gets resynchronized when the imprecision reaches a rather large value. For short term usage that means it is just as preice as it was before.
Most ACs are not even worth the keystrokes to insult them. Be generically insulted and ignored otherwise.
you could just buy a clock that receives the atomic radio signal....
-------
"In times of universal deceit, telling the truth becomes a revolutionary act."
-- George Orwell
Edgar Allan Poe about this? The timing on his pendulum was the pits!
One line blog. I hear that they're called Twitters now.
if atomic precision is that important then it would probably be better to actually add something to the fulcrum (or whatever you call that in a clock) utilizing a winding spring to give an extra boost in either direction. This could be as fancy as a small servo or just a simple electrical winding spring like in old buzzers and ringers. No clock is needed, only something to receive the signal and simultaneously correct for delay and error in the actual pendulum swing.
If the atomic clock is what's actually keeping the time, then the pendulum portion is merely superfluous. It's like placing a bicycle inside a Hummer, then claiming that you've created a bicycle with the power and speed of a Hummer! No one would find that story interesting, so I'm perplexed as to why this story is any different.
When someone creates a pendulum clock that actually keeps time in a precise manner, I'll be interested. Until then, why was this story posted?!
If someone says he and his monkey have nothing to hide, they almost certainly do.
YOU FAIL IT!
Now you can get atomic clock precision on your computer too! Much like the 'atomic clock accuracy on a pendulum clock' seen on /., the atomic clock on your computer is "set" by using the ntp protocol. Wow!
Uh...atomic clocks don't keep time precisely...that is what the atomic part does...a couple of decaying 'trons are compared and a resultant time is calculated, and the master clock is adjusted via atomic update.
Consider where I work - we have a very accurate 10 MHz reference to sync all our RF gear to. We need that ref to be tracable to the National Bureau of Standards. Now, it would be somewhat impractical to check with the Bureau 10 million times a second (anybody want to run a fiber from Boulder to Wichita just for the time sync?).
Before I go on, let me point out the difference between precision, accuracy, and repeatability.
From a metrological standpoint, having more accuracy than repeatability is useless. Having more precision than accuracy is also useless. (Ignoring tricks like averaging for the moment.)
Back to the example. What we do is to have a very high precision and stable oscillator (we used to use a rubidium standard). It has a long term stability of about 10E-9 and a short term stability of 10E-12. In other words, over a short period of time the thing will drift not more than one part per trillion, and over the long term (days) it will drift about one part per billion.
Now, that is running next to a GPS receiver that gives us a time tick synced to the Bureau. Every second the GPS time is compared to the local time standard, and an error value is computed. That error value is averaged over a long period of time, and used to gently tweak the rubidium standard. Thus, over the long run the drift is reduced to level of the cesium clocks, about 10E-13.
So we have atomic clock accuracy but rubidium clock precision and repeatability.
Now, if you used the same sort of technique on a pendulum clock - measure the error between the clock and the GPS, average, filter, and apply - you would have atomic clock accuracy with pendulum clock precision. Granted, I would not want to use the clock's time for reporting astronomic phenomena where the precision must be very high, but for normal use this would be quite good enough.
www.eFax.com are spammers
... to an LED?
Or better yet spend $25 on a Casio?
I am very small, utmostly microscopic.
Feed the camera into a PC (running Linux if you prefer). Have a vision system (lots of software) analyze the motion and compare it to the results from the USNO / NIST atomic clock. Control the timing of the clock dynamically by placing a small stepper motor on the pendulum that moves the weight up or down...
It's not an April Fool's joke, but it is rather impractical.
Well, that's the point, isn't it? I mean, what's the point of being a geek if you can't do geeky, pointless things?
Ed Wedig
Graphic design services
docbrown.net
to suggest that if one is going to go to the length of having a signal from an atomic whatsit, that one could far more simply DISCONNECT the pendulum and run the clock hands by the atomic clock, and just have a simple motor keeping the pendulum swinging away?
Or is the tremendous effort to keep the weights/pendulum the 'driver/regulator' for the clock mechanism the point? Maybe I'm just a mechanical clock philistine.
-Styopa
No, "Big Ben" is really the name of the giant rat in the tower whose job it is to run on the treadmill that winds the clock.
OK, so I'm several days late for April Fool's, *and* I'm a Willard fan. But at least I dodged the third strike because I'm not an AC!
--Rob
Third strike: Unfunny -5. Oops.
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Are we sure this isn't a joke? The article is clear about how you lose an hour in the fall but how do you gain an hour in the spring? Stop the clock for 11 hours?
Take a couple of pictures around the expected time, see which way it is moving and how close to optimum. Magnets, LEDs, now you are talking special circuitry. Webcams are simple and cheap.
Infuriate left and right
That's not having an atomically precise clock; that's using an atomically precise clock to automatically adjust your not-so-precise clock.
Vintage computer games and RPG books available. Email me if you're interested.
So this is not a Rube Goldberg device, it is a piece of conservation technology :-)
Why not eliminate the Rube Goldberg device and get to the root of the problem: Eliminate DST
So given the added risks of DST-lagged public behind the wheel, a fatigued public safety sector cleaning up after it, and the farmers that feed us having to go out of thier way to get the food out, not to mention the abovementioned problems with historical clocks breaking when they go to lag or jog them an hour, can society really afford to continue using DST in the long term?
Help us build a better map!
That's The Dumbest Thing I've Ever Heard!
Must-not-watch TV!
The camcorder seems a little extravagant. Why not just use an induction loop (a la EZ-Pass or bicycle spedometers) to sync the pendulum with the atomic clock?
Statistically speaking, there's a 99.998% chance that my IQ is higher than yours. Get over it.
I'd like to point out for those moderators out there who may not be familiar with the Slashdot code of community conduct, parent was jokingly playing the role of karma whore police, because grandparent was jokingly playing the role of slashdotted story reposter while actually playing the role of that-guy-who-points-out-the-slashdot-summary-has-n othing-to-do-with-the-story. Grandparent was "Funny," but absolutely not "Insightful," unless one means insightful into the shortcomings of slashdot which are traditionally modded either "Funny" or "Offtopic." Parent is not a troll, but a prankster playing along with grandparent posing as a troll, and doing so just a little too subtly it would seem. Grandparent should be Score 3 or 4:Funny, and parent should be score 1:Funny.
Thank you for your attention. You may now return to modding down RIAA appologists.
The ______ Agenda
Image analysis through a camcorder, comparison with an atomic clock, manipulation of the pendulum with a mechanical arm? Where is the geek factor in that?
What this projects needs is a
GRAVITATIONAL CONSTANT MODULATOR (GCM) to control the period of the pendulum. Now that would be much cooler than some stupid magnets.
You know, electronics a better product doth not mache. It's the whole routine of well winding setting tempering and discoplin (oiling the bobs gears cogs etc.) These pendulums are at least 100 years old and still keep working far better than my moder day windup wrist watch. And don't add linux to them that'd make them work even worse
Does this mean that I've bred a superhorse when I put a race horse in a trailer and drive him cross-country at 80mph?
Stupid headline detracts from otherwise neat hobby-hack.
"Reality is that which, when you stop believing in it, doesn't go away." - Philip K. Dick
Instead of the piston, etc. set the pendulum so that its natural frequency is slightly fast, just enough so that with setting error, temperature effects, etc. it will never run slow. Then phase-lock the pendulum to the atomic clock, using a non-contact electromagnetic brake (eddy current) slowing the pendulum as the control mechanism. The pendulum frequency can be sensed with something less complicated/more reliable than a video camera, such as a magnetic sensor. as the article says, some of these clocks have been running for centuries. Adding an overly complicated kludge to set the time really seems like an offensive thing to do to them!
Like, if I'm not for me, then fer shure, like who will be? And if, y'know,
if I'm not like fer anyone else, then hey, I mean, what am I? And if not
now, like I dunno, maybe like when? And if not Who, then I dunno, maybe
like the Rolling Stones?
-- Rich Rosen (Rabbi Valiel's paraphrase of famous quote
attributed to Rabbi Hillel.)
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