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A curious phenomenon called 'Etak'

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Re: A curious phenomenon called 'Etak'

#81

Post by bsenftner »

KingOfCoders wrote: post #48
sllabres wrote: post #44

Earlier quoted context omitted.

Very interesting, i've just yesterday wrote about the successor of EVA, the TravelPilot IDS [1] which was commercially available. But I didn't knew that there was another system 5 years ahead. Both (Etak and TravelPilot IDS) seems to use kind of a vector display. Does someone know if this is for better resolution or better contrast, or both or if there is another reason? https://www.bosch-presse.de/pressportal/de/en/…

There is no conventional resolution to vector displays (though monitors have limitations). Reminds me at one point in time I owned a Vectrex, which had much cleaner lines than any other console, even much better than my later, much more expensive Amiga or (early) PCs. "This Vectrex does things I never thought possible" https://www.youtube.com/watch?v=8Dv15YRAmzM Only got that feeling back with Retina displays.

I worked at the company that made the Vectrex, Jay Smith was a wonderful guy. Super brilliant too: the world of PSX Bowling games was his creation, he wrote the first bowling physics sim using Excel, and we hired some guy with a PhD in Statistics who wrote Jay's algorithm in assembly for the PSX, and the 3D bowling genre was launched.

Re: A curious phenomenon called 'Etak'

#84

Post by em-bee »

ghostly_s wrote: post #57
toast0 wrote: post #42

Earlier quoted context omitted.

I don't think so... I think heads up for the digitizing indicates that the digital map was overlayed on top of the (scanned) source image? As opposed to digitizing from a paper map where you have the map on a surface in front of you, and a digital map hopefully on a screen in front of you (but they did say some were digitizing blind before this?) and you're trying to get the digitized version right by looking between…

I’m guessing the 'blind' method looked something like using one of the early graphics tablets to trace routes or tap control points on a paper map according to a sequence displayed on a text terminal, with no graphical feedback to confirm the vector data during input.

in 1988 i was doing an internship at a company designing ship propulsion systems. they had a CAD computer with with a huge screen and tablet. not sure how old that device was or how expensive but i guess in '85 the technology was not far away.

digitizing blind at that point would mostly be used because it was cheaper than getting a graphics capable computer.

using a projector instead of a screen would be enough to devise a system where the digital image is shown on top of a printed map. so when they came up with that idea they probably already had most of the pieces they need to make it work.

Re: A curious phenomenon called 'Etak'

#85

Post by mauvehaus »

SamBam wrote: post #17

The name is perfect. "Etak" refers to a system of navigation used by Micronesian and Polynesian seafarers to navigate from island to island in the vast Pacific Ocean. Much like this device, it operates by "augmented dead reckoning" (as it says in TFA). The etak system of navigation involves navigating by stars and ocean swells to get the heading, but a key issue when navigating by dead reckoning over long distances i…

Another book specifically about the Polynesian navigators is The Last Navigator. Having no experience navigating at sea, parts of it were a bit over my head, but it was a great read. It also goes into the culture of the people who are the subject of the book.

Re: A curious phenomenon called 'Etak'

#86

Post by stavros »

SamBam wrote: post #17

The name is perfect. "Etak" refers to a system of navigation used by Micronesian and Polynesian seafarers to navigate from island to island in the vast Pacific Ocean. Much like this device, it operates by "augmented dead reckoning" (as it says in TFA). The etak system of navigation involves navigating by stars and ocean swells to get the heading, but a key issue when navigating by dead reckoning over long distances i…

Oh, I thought it was just the name "Kate" reversed.

Re: A curious phenomenon called 'Etak'

#87

Post by mauvehaus »

LeoPanthera wrote: post #50
tgsovlerkhgsel wrote: post #47

The article claims that the "match roads by turns" technique "was later adopted by all navigation apps". Does anyone know if this is true? My impression was that they rely on GPS position only for positioning, even though modern phone hardware should give really nice gyroscope/accelerometer data.

Virtually all car navigation software, or phone GPS apps in driving mode, will "snap" to a nearby road if the GPS indicates that you are traveling parallel to one. This compensates for minor GPS reception errors. This can occasionally , in rare situations, be a problem, if you have frontage roads very close to a highway, they can sometimes get confused about which road you are actually on.

I love when I've been traveling at highway speed down a highway for over an hour, and suddenly my GPS starts giving me directions back to the highway from some nearby parallel road when I haven't so much as passed an exit.

Re: A curious phenomenon called 'Etak'

#88

Post by stavros »

m463 wrote: post #64

I had a friend who had one of these in the mid-90's. It was pretty cool (at the time) I remember installation wasn't trivial. It needed a lot of futzing with the car. I remember the wheel rotation sensors, and they are briefly mentioned in the article. Smazing that nowadays all this stuff is solid state and in your pocket.

None of this stuff is solid state. What's solid state is completely different stuff, namely GPS. There's also a gyroscope, accelerometer, and compass, but I don't know if those can be considered solid state.

Re: A curious phenomenon called 'Etak'

#90

Post by myself248 »

LeoPanthera wrote: post #50
tgsovlerkhgsel wrote: post #47

The article claims that the "match roads by turns" technique "was later adopted by all navigation apps". Does anyone know if this is true? My impression was that they rely on GPS position only for positioning, even though modern phone hardware should give really nice gyroscope/accelerometer data.

Virtually all car navigation software, or phone GPS apps in driving mode, will "snap" to a nearby road if the GPS indicates that you are traveling parallel to one. This compensates for minor GPS reception errors. This can occasionally , in rare situations, be a problem, if you have frontage roads very close to a highway, they can sometimes get confused about which road you are actually on.

It's incessant for me; a significant part of one of my frequent routes is on the service-drive that parallels a major freeway, after taking an exit, but prior to diverging. Depending on traffic, though, it may also be advantageous to stay on the freeway, so both are valid parts of the route.

If Waze instructs me to take the exit, then it assumes I'm on the service drive, even if GPS says I'm still on the freeway. And vice-versa, more problematically -- if I impulsively take the exit, it assumes I'm still on the freeway even if GPS clearly shows I'm on the service drive.

(I can confirm this by running a spare laptop with a USB GPS as a logger, while my iPhone runs Waze. Overlay the GPX on a map later and it's super obvious whether I took the exit or not, but either the Apple location provider or Waze staunchly ignores reality in favor of obsessive road snapping.)

Where this gets stupid is, if there's a traffic jam on the freeway and I dip onto the exit to avoid it, now Waze sees me flowing freely down the service drive, assumes that it's the freeway that's flowing freely, and disbelieves other users who report traffic there. Even as the service drive curves and diverges and I follow the curve, it doesn't retroactively say "Oh jeez, he must be on the service drive after all, adjust the previous data to apply to the service drive and not to the freeway!". So the bad data continues to corrupt the traffic picture and encourage other users to get stuck in traffic they can't report.

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