The consumer electronics industry has shipped hundreds of millions of touch screens in the last few years and i've not seen a single article complaining that they opened up their new tablet/phone to find it mis-calibrated and that their touches were off my such a huge margin. Why are voting machines apparently subject to calibration problems that other touch screen devices are not?
I remember the old Nintendo DS touch screen, which was resistive, required user calibration where you would press on the corners of the screen. If you missed the corners (which, with the relatively thick stylus and the relatively thick bezel on the original DS, wasn't uncommon), the accuracy of your touch positions would be very notably off, to the point that using touch-screen keyboards in some games would be difficult.
Obviously I don't know for sure if this was the exact case with this voting machine, but the point being, some touch screens do require calibration and there is a chance for error. Or, of course, it could simply have been a factory mistake.
Either way, I doubt there's any malice behind this error.
This is an example where technological ignorance is dangerous because it leads to the wrong conclusions.
Multi-touch screens as used in smart phones use capacitive touch sensing technology, they do not require calibration.
Cheaper, older touch screen systems (such as those used with ATMs or voting machines) use resistive touch technology, they absolutely require calibration.
Honestly curious - what kind of abuse could cause a calibration error?
My kids abuse my iPad pretty heavily but generally smacking on the screen with their hands and fingers a lot but I still have never seen it mis-calculate a touch.
iPads used capacitive touchscreens which aren't prone to the same sorts of calibration issues that resistive touchscreens are.
I don't know much about electronic voting machines but I wouldn't be surprised if they mostly used resistive touchscreens (which are historically much cheaper to produce).
If you ever used a Palm Pilot, you've seen this sort of calibration issue. Given the state of government procurement, they're likely using that cheaper, crappier tech in most areas.
Most likely it's the difference between capacitive versus resistive screens. If you purchased your phone based on the lowest bidding vendor, I'd bet there be a lot more problems with it too.
The touchscreens you see in modern consumer electronic devices are capactive touchscreens. I think the iPhone was the first major device to ship with a capactive touchscreen, prior to that, resistive and infrared touchscreens were a lot more common (and cheaper).
If you've ever interacted with a touchscreen at an ATM, mall kiosk, or airport kiosk, it's likely that they were resistive or infrared based, and more susceptible to calibration errors.
Miscalibrated devices shipped to consumers get returned, resulting in extra costs to the retailer or manufacturer. Miscalibrated voting machines don't.
