One of the more novel talks we saw at Defcon was [Zac Franken] presenting on access control systems. He covered several different types, but the real fun was his live demo of bypassing a hand geometry scanners like the one pictured above. With the help of two assistants, 4 pounds of chromatic dental alginate, and 5 liters of water, he made a mold of his hand. The box he placed his hand in had markings to show where the pegs on the scanner are located. After 2 minutes he could remove his hand from the cavity. They then filled the mold with vinylpolysiloxane, making sure to remove all bubbles. 20 minutes later the hand was solid and passed the scanner’s test. This may not be a completely practical attack, but it does defeat the overall idea of biometrics; biometrics are built on the assumption that every person is unique and can’t have their features reproduced.
[Zac] also showed an interesting magnetic card spoofer that emulated all three tracks using coils of magnet wire. We hope to see more about that in the future.
Here’s an interesting grabber hand built for use on an ROV. This grabber is a novel use of a very common and extremely cheap electric screwdriver, that is probably found in everyone’s toolbox. It is also a great way to reuse that small electric screwdriver you have kicking around that uses proprietary batteries that are not worth replacing. Many of the ROV’s covered previously could benefit from such a powerful device built from very common materials off his parts list. Because the screwdriver was extremely cheap the designer chose not to completely seal the housing.
It seems like this simple design that could be used in many robotic projects and by simply changing the jaws could yield other creative uses. The first thing that comes to mind is to upsize this hack into something bigger and stronger. Either way, you might not want to get your fingers in there.
When Boing Boing Gadgets posted about this $13 robot hand music box, we immediately thought “OH EXPLOITABLE!”. Over the years, we’ve acquired quite a bit of cheap trash just operating under the assumption that we would turn it into something else. Most of our acquisitions are Woot‘s fault. Just this morning we were dismayed to find out that the purveyor of cheap electronics had already sold out of animatronic Elvis heads. Now that would have been fun. We’ve purchased things like Tony Hawk helmet cams, jumbo remotes, Bluetooth headphones, Gyration mice, IMFree chatpads, and many other items of questionable use thinking that some day we’d use it. How about you? What sort of irrational purchases have you made and what would you do with a $13 mechanized hand?
[Just as we were wrapping this up, Woot posted a $49 HMD; you better believe we bought that.]