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> To solve this problem Etak invented ‘augmented dead reckoning’. This used a process to match the position given by the navigation sensors to a topologically c

> To solve this problem Etak invented ‘augmented dead reckoning’. This used a process to match the position given by the navigation sensors to a topologically correct electronic map. Whenever the vehicle turned you made the assumption that you’re driving on a road. At that point the location could be ‘snapped’ back to the road and the error from the sensors could be reset. This technique was later adopted by all navigation apps and is still in use today. No way did they invent this. Not even close! This is called map matching. It predates Etak by at least 20 years, if not more. This paper was published a decade before which does exactly this: Lezniak TW, Lewis RW, Mcmillen RA. A dead reckoning/map correlation system for automatic vehicle tracking. IEEE Transactions on Vehicular Technology. 1977 Feb;26(1):47-60. The government was building out this technology in the 50s, here's a RAND report about that. https://www.secretsdeclassified.af.mil/Portals/67/documents/RM0756-1%20Survey%20of%20Self-Contained%20Navigation%20Systems.pdf https://www.secretsdeclassified.af.mil/Portals/67/documents/... I suspect there are even earlier examples.

kqr 3y ago
This was my sense as well. The device looks and is described like something I would not be surprised to find on a 1970s warship or spy plane to aid navigation. Not with street maps, specifically, of course, but something similar! Still impressive to get it into a consumer-sized (and almost consumer-priced) box.
lsaferite 3y ago
I mean, if that paper wasn't declassified until 2017, what are they chances they knew about the prior art exactly? I'm not disputing your assertion, but perhaps I'm a little more charitable in thinking they could have independently invented the same thing and believed they were the first since the one you mentioned was apparently classified.
- MBCook 3y ago
  Right. Independent invention happens all the time.
- light_hue_1 3y ago
  The other paper I showed was always public over a decade before.
  - lsaferite 3y ago
    Unfortunately, I cannot access the paper and as such cannot give any meaningful feedback. Edit: Funnily enough, searching on google for this paper, your comment is the second result.
    - lsaferite 3y ago
      As an aside, wanting me to pay $33 to read a PDF of a paper from 46 years ago is... unfortunate. (I have a list of other words I'd rather use, but I'm being civil)

kqr 3y ago

This was my sense as well. The device looks and is described like something I would not be surprised to find on a 1970s warship or spy plane to aid navigation. Not with street maps, specifically, of course, but something similar! Still impressive to get it into a consumer-sized (and almost consumer-priced) box.

lsaferite 3y ago

I mean, if that paper wasn't declassified until 2017, what are they chances they knew about the prior art exactly? I'm not disputing your assertion, but perhaps I'm a little more charitable in thinking they could have independently invented the same thing and believed they were the first since the one you mentioned was apparently classified.

MBCook 3y ago
Right. Independent invention happens all the time.
light_hue_1 3y ago
The other paper I showed was always public over a decade before.
- lsaferite 3y ago
  Unfortunately, I cannot access the paper and as such cannot give any meaningful feedback. Edit: Funnily enough, searching on google for this paper, your comment is the second result.
  - lsaferite 3y ago
    As an aside, wanting me to pay $33 to read a PDF of a paper from 46 years ago is... unfortunate. (I have a list of other words I'd rather use, but I'm being civil)