Slashdot Mirror

← Back to Stories (view on slashdot.org)

Optical Mice Used To Detect Counterfeit Coins

Posted by timothy on from the is-there-anything-optical-mice-can't-do? dept.

JimXugle writes "El Mundo reports that Spanish researchers at The University of Lleida have used a modified optical mouse to detect counterfeit €2 coins (Original article, in Spanish) with a success rate comparable to that of an expert trained to do so. Details are to be published freely in the journal Sensors."

25 of 123 comments (clear)

  1. Genius you see... by Monkeedude1212 · · Score: 5, Funny

    The laser from the mouse will heat up the chocolate inside of counterfeit coins, thus exposing the fakes and creating a mess.

    1. Re:Genius you see... by Ukab+the+Great · · Score: 2, Insightful

      And that's why Spain will never get to host the world Dreidel championships.

    2. Re:Genius you see... by Anonymous Coward · · Score: 2, Funny

      My mouse has a laser diode.

      Newer Mac mice are cybernetic, touch sensitive because it has a real piece of scrotum skin stretched over the surface.

    3. Re:Genius you see... by zoney_ie · · Score: 2, Funny

      A real mouse works for that too - they'll happily gnaw through the metallic shell to get at the tasty chocolate inside.

      --
      -- *~()____) This message will self-destruct in 5 seconds...
  2. Who counterfiets 2-Euro coins anyways? by davidwr · · Score: 5, Insightful

    Geesh, can you get me a mouse that detects North Korean bogus US$100 bills?

    --
    Knowledge is how to play a game, intelligence is how to win, wisdom is knowing what game to play.
    1. Re:Who counterfiets 2-Euro coins anyways? by von_rick · · Score: 4, Funny

      I can get you a mouse, but you will need to write the algorithm yourself.

      --

      Face your daemons!

    2. Re:Who counterfiets 2-Euro coins anyways? by xaxa · · Score: 3, Informative

      I don't know about €2 coins, but loads of £1 coins are counterfeit -- perhaps 5%. The €2 (and 1) are bi-metallic though, so presumably harder to fake.

      Under UK law (as that page explains), once you know a coin is counterfeit it's illegal to give it to anyone (except the police) or to keep it. Daft, but it means it's in my interest not to identify counterfeits. (Unless, possibly, I checked every time I was given change. But that's not realistic.)

  3. How does it compare to a vending machine? by istartedi · · Score: 3, Insightful

    In what ways does it defer, if any, from the techniques used in vending machines?

    If it's better, patent and sell to vending companies? Yeah... patents are evil; but maybe a novel application of an existing technology isn't so evil in this case--provided it really is novel and not just a poor-man's vending machine detector, in which case the vending machine companies may already have a patent on it...

    --
    For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares"?
    1. Re:How does it compare to a vending machine? by von_rick · · Score: 2, Interesting

      The corollary to this mouse-hack is that you can use your mouse as a scanner and coupled with an OCR program, use it for getting scribbled notes uploaded to your computer.

      --

      Face your daemons!

    2. Re:How does it compare to a vending machine? by shankarunni · · Score: 3, Informative

      Vending machines rely on mechanical factors, mostly: Weight, size, metallic composition (measured by conductivity characteristics).

      This one seems to focus on the graphics on the faces. It's complementary.

    3. Re:How does it compare to a vending machine? by BKX · · Score: 4, Informative

      Vending machine detectors are usually just magnets (at least in the US). Very few countries make their coins with enough iron, nickel, or cobalt to be magnetic, so a magnet can pick out most slugs (the usual form of counterfeiting used on vending machines). I know; I own vending machines.

      Also, it's OT, but your sig annoys the crap out of me. I use whom correctly all the time, "intensive purposes" is retarded. Begging the question, though, seems to have actually changed meanings over the years, so, being a descriptivist, I'll give you that one.

    4. Re:How does it compare to a vending machine? by mea37 · · Score: 2, Funny

      "It's complementary"

      'What a lovely counterfeit'?

    5. Re:How does it compare to a vending machine? by uglyMood · · Score: 5, Funny

      Complement: to make complete.

      Compliment: to tell a falsehood.

      --
      "No matter where you go, there you probably are." -- Buckaroo Heisenberg
    6. Re:How does it compare to a vending machine? by quercus.aeternam · · Score: 3, Funny

      I don't know where you learned the meaning of compliment, but I am in awe.

    7. Re:How does it compare to a vending machine? by Drishmung · · Score: 5, Informative
      Are they just magnets?

      My understanding was that the coin falls into a balanced cradle that measures the diameter and weight. If it's the wrong size it is rejected (and can fall through to another cradle that tests for a different value coin---and so on). If it is the right size but the wrong weight the cradle tips too far or not far enough and deposits it in the reject slot.

      If it's the right size and weight then the coin drops between two magnets onto a little anvil. If the metallic composition is right the coin will slow just enough passing through the magnets to hit the anvil at the right place and speed to bounce into the accept slot. Anything else and it misses.

      The end result is a very quick, accurate but cheap analysis of the coin's weight, size and metallic composition.

      I know that's the way it used to work. Have they dumbed down the machines recently?

      --
      Protoplasm. Quiet Protoplasm. I like quiet protoplasm.
    8. Re:How does it compare to a vending machine? by uglyMood · · Score: 3, Funny

      Stop lying.

      --
      "No matter where you go, there you probably are." -- Buckaroo Heisenberg
    9. Re:How does it compare to a vending machine? by Valdez · · Score: 3, Interesting

      For all intensive purposes, "whom" is no longer a word. That begs the question, "who cares?"

      "intensive purposes" is retarded

      Perhaps the poster was going for "for all intents and purposes"?

      If so, ouch.

    10. Re:How does it compare to a vending machine? by santathehutt · · Score: 3, Informative

      Back in the 90's I worked for a company that built coin changers and acceptors. Even back then they were using a more advanced method than the one you describe. The acceptor was actually the part that determined what type of coin was inserted and would reject it if it was a slug. The acceptor worked on the same principle as a metal detector. Since coins are made up of a unique mix of metals the acceptors could be "tuned" to accept a certain coin by dropping versions of that kind from different years and differing conditions. This would create a range of values for each coin. When a coin is dropped into the acceptor it gets a reading of the coin. If it is in the range of one of the coins the acceptor is programmed to accept then the coin is routed to the proper coin tube or the cash box if the tube is full. Otherwise it will be rejected as a slug. The acceptor is actually plugged into the top of the changer as a complete unit. For what it's worth I did see an acceptor there one day that worked similar to the way you described, but I believe it was from the 70's or early 80's.

  4. Re:16x16 pixels? by logjon · · Score: 2, Insightful

    You could also try not missing the point. Or the the part of the summary that says "with a success rate comparable to that of an expert. Or the point, that being that sensors are cheaper and generally more easily employable than people.

    --
    The stories and info posted here are artistic works of fiction and falsehood.
    Only fools would take it as fact.
  5. Fun fact #65 by dvh.tosomja · · Score: 4, Informative

    Did you know that there are more than 260 different euro coins from 19 countries to present day!

  6. The conclusion from this by Anonymous Coward · · Score: 2, Interesting

    If you compare a counterfeit-coin-detecting expert with a purpose-built handheld device, the answer is pretty obvious.

    Until the day the people who print counterfeit coins buy a purpose-built handheld device, of course, and there's no expert around to reprogram the device because he jumped off a bridge after losing his job.

  7. Re:16x16 pixels? by pz · · Score: 2, Insightful

    Somehow I doubt a 16x16 pixel grayscale sensor is going to detect counterfeit coins any better than the human eye, but maybe I should read TFA before I jump to judgement...

    And maybe before posting, too? Just a suggestion.

    Generally, if you're about to post something that is along the lines of, "this couldn't possibly work because ..." without (a) having read the article, and (b) being an expert in the field, best to think twice.

    --

    Put my fist through my alarm clock with its ding-dong death inside my ear. - The Blackjacks.
  8. Re:who would go through the trouble? by belmolis · · Score: 4, Funny

    Counterfeit $100s can be identified by the absence of cocaine residue.:)

  9. How by SEWilco · · Score: 2, Insightful
    There are several methods.
    1. Smash coin with mouse. If coin bends, it is fake.
    2. Put mouse on balance scale. See how many coins are required to balance the scale. If the number of coins is different from the number of genuine coins required, at least one fake has been detected.
    3. Use the coin to pry the mouse apart. Look for scratches exposing a different color on the coin.
    4. Put the coin on the mouse. Burn the mouse. See if the coin melts.
    5. Put the coin on the mouse. Pour on the coin an acid which does not affect a genuine coin. Check if the coin survived.
    6. Line up coins the length of the mouse. See if the number of coins matches the number of genuine coins.
    7. Use coins to buy a mouse. See if the cashier rejects any coins.
    8. Use coins to pay for a call to the Secret Service. Report that someone might have used a counterfeit coin to pay for a phone call from this phone booth. Leave the mouse in the phone booth. Repeat until the "mouse counterfeiter" or the "mouse crank caller" is caught.
  10. Re:Other coin facts. by nuckfuts · · Score: 2, Interesting

    We have a coin of our own that is not always accepted, whereas we readily accept US (foreign) coins.

    You don't see the irony in that?