[HN Gopher] Electro Gyro-Cator
___________________________________________________________________
Electro Gyro-Cator
Author : gumby
Score : 97 points
Date : 2023-01-28 15:01 UTC (3 days ago)
(HTM) web link (en.wikipedia.org)
(TXT) w3m dump (en.wikipedia.org)
| causi wrote:
| Meanwhile my 2022 smartphone sometimes decides it's going the
| opposite way down the road because its dash mount is pointed at
| the driver instead of straight at the back seat.
| Arrath wrote:
| Or decides that after an hour of travel on the highway, at
| highway speeds, my car shifted 15 meters to the side and I'm
| actrually doing double the speed limit on the frontage road.
| No, wait, I'm on the highway. Oh nope my bad, actually on the
| frontage road.
| fortylove wrote:
| So true. Oh wait, I took that exit. No wait I didn't. No
| wait, I'm back on the entrance ramp!
| jollyllama wrote:
| I'm pretty sure a lot of military submarines use inertial
| navigation.
| askvictor wrote:
| That seems really the only option; but how do they account for
| currents? Or do they match the sensor data with the engine
| output to correct for this?
| AnIdiotOnTheNet wrote:
| I think a lot of military craft do. I know for certain a lot of
| jets do, and I think tanks do as well. Unsure outside of that.
| pierrebeaucamp wrote:
| It's also being used in aerospace & naval navigation.
| Interestingly, the more advanced systems use fibre-optic
| gyroscopes, see https://en.wikipedia.org/wiki/Fibre-
| optic_gyroscope.
|
| Northtrop Grumman manufactures those, for example.
| jihadjihad wrote:
| Looks like it had a base plate of pre-famulated amulite
| surmounted by a malleable logarithmic casing...I can see why it
| was so expensive!
| mattkrause wrote:
| Gotta get that side-fumbling under control!
| pmdulaney wrote:
| Wow. I imagine there was quite a bit of drift.
| krisoft wrote:
| Yes. I found this paper which measured the errors of the
| system: https://apps.dtic.mil/sti/pdfs/ADA138283.pdf
|
| They performed two kind of measurements. On a bench they
| measured the drift of the helium-flow gyroscope in itself, and
| then they took the whole system to drive test loops and
| measured the errors in eastings and northings.
|
| Quite a thorough job in fact, but I guess that is what you get
| if you ask a rocket scientist to evaluate a new-fangled vehicle
| navigation tool.
| machinehum wrote:
| Thanks for the link to the paper, this was an insane amount
| of work.
| analognoise wrote:
| ...this place is so weird, I love it so much.
|
| Like if there was going to be one place where a random
| comment links to an actual Defense Technical Information
| Center technical report evaluating the system, it's here.
| rvnx wrote:
| Then you may find even more happiness on Reddit where you
| can find specialists about everything
| analognoise wrote:
| I'll bet HNers have a collection of fascinating
| subreddits.
|
| HN is better - it's broader and there's usually amazing
| takes in the comments (amazing good, not YouTube
| "amazingly WTF" style comments)
| olyjohn wrote:
| It doesn't say in the article, but I'm pretty sure you drop in
| a slide with the map on it, and then you move the pointer to
| your current location. So you reset the drift every time you
| use it.
| eckza wrote:
| Probably not, as it was only optioned to the Accord and Vigor,
| which are FWD vehicles.
|
| http://instantrimshot.com/
| kojeovo wrote:
| Handbrake!!!
| aidenn0 wrote:
| Don't change the subject; we are talking about cars, not
| video encoding!
| leokeba wrote:
| Even with data from all four wheels the system as it is
| described cannot prevent drift altogether. Wheel diameter is
| variable depending on many factors, tires can lose grip on
| the road, and also the earth is not perfectly flat. There
| would be other sources of inaccuracies, but basically in any
| real-world situation you need some kind of absolute position
| source to get drift-free location data. The trick is that it
| can be very noisy and low bandwidth if you integrate it with
| other sources of data like and IMU.
| amelius wrote:
| You could compensate for drift if you use a map as a
| constraint on the position.
| kube-system wrote:
| The comment you replied to was an attempt at a joke
| gtirloni wrote:
| I know explaining a joke ruins it but I failed to
| understand it so far.
| aidenn0 wrote:
| "Drift" is another term for understeer which is when the
| rear-end of the car loses traction in a turn. It tends to
| be easier to induce (accidentally or on purpose) in a
| rear-wheel-drive car.
|
| I should note that my ~2005 MY Ford Focus would
| absolutely understeer if you enter a turn too fast
| without applying power.
| eckza wrote:
| Are you lifting right before you start to turn in?
| That'll do it, because lifting off the throttle abruptly
| will shift weight to the front, which will unweight the
| rear; and sometimes that little weight transfer is all it
| takes to break the back end out a bit. (Used to do this
| regularly in a Taurus that I had the pleasure of driving
| for a few months.)
| kube-system wrote:
| Yeah, the first gen focus is pretty easy to induce lift-
| off oversteer in. The rear end weighs nothing and the
| suspension sits strangely high.
| eckza wrote:
| > Lift-off oversteer
|
| was on the tip of my tongue. Thank you!
| kube-system wrote:
| Oversteer is when the rear end loses traction. Understeer
| is when the front end loses traction.
| aidenn0 wrote:
| holy shit I wrote it exactly backwards. I didn't have my
| coffee this morning.
| kube-system wrote:
| They are intentionally misinterpreting "drift" as the
| driving technique (often associated with RWD vehicles)
| rather than the intended meaning.
| forgotmypw17 wrote:
| This thread just keeps drifting further and further away
| from the original topic.
| Xylakant wrote:
| The device is described as using a gyroscope to measure
| movement, so it would be independent of wheel diameter and
| grip. Gyroscopes still drift, so occasional calibration
| against an absolute position source is still required.
| kube-system wrote:
| The device uses a gyroscope to determine direction. But a
| gyroscope is unable to measure distance travelled. So
| this device also attaches to the transmission to
| determine distance.
|
| > A special servo gear was also attached to the
| transmission housing to feed information to the Gyro-
| Cator to help maintain position, map speed and distance
| traveled.
| Gordonjcp wrote:
| Well, I thought it was funny.
| dfox wrote:
| You can drift with anything that has wheels, or even, tracks,
| somebody did that.
|
| And drifting with FWD german family car is one of my favorite
| activities.
| zh3 wrote:
| Depends on the qualities of the gyros. My step-dad flew 707's
| between NY and London, and INS on those used the same kind of
| system (obviously more pro version) - one of the reasons it was
| no longer necessary to carry a navigator in the cockpit.
| aidenn0 wrote:
| IIRC some pre-GPS cold-war era spy-planes used an INS that
| was corrected for error with an analog-computer celestial
| navigation system.
| elil17 wrote:
| Yep - 3.5% of distance traveled (i.e. drive 1 km and you'd have
| 35 meters of drift)
| hammock wrote:
| Not bad.
|
| When you consider a city block is about 100m, you could drive
| 3km before being off by a street so as to miss your turn.
|
| On the highway it's even better- if exits are 5km apart, you
| can drive 142km before being so far off you might miss your
| exit
| dfox wrote:
| That is surprisingly close to what I used as a good-enough
| error in fallback route estimator in our TSP/VRP solver. I
| came up with that essentially by curve-fitting great-circle
| WGS84 distances and really traveled distances between my
| favorite pubs and it seems to work (bear in mind that it is
| the last fallback and there is A* on map data and ML-ish
| thing before that)
| hammock wrote:
| Everything is fractal/self-similar
| pantulis wrote:
| That's not that bad, specially for solo driving where you
| cannot use a regular road map (remember those?).
| dfox wrote:
| Let me guess: you didn't ever solo drive for work. You can
| certainly use a paper map while driving. When it gets too
| distracting to safely drive then you are lost and should
| stop and use the paper map more thoroughly to find out
| where you are.
|
| Source: I intentionally tried to be a parcel delivery
| driver without a GPS-based navigation and only with regular
| road map and printed out rough plan of the route. Not to
| mention that for most of my long driving trips I used to
| simply print out the itinerary from RAC RoutePlanner and
| ignore the navigation (it is a shame that this service
| apparently does not exist anymore).
| actionfromafar wrote:
| Wasn't there another turn-by-turn system of similar vintage which
| worked similarly and was surprisingly accurate, because it used
| turns as checkpoints to null the error and reset where it was?
|
| I want to say it was an American system.
| e44858 wrote:
| There was an older system that used a cassette tape which told
| you to make a turn when the odometer reached a certain
| distance: https://jalopnik.com/this-cassette-tape-based-
| navigation-sys...
| fipar wrote:
| Do you mean this?: https://arstechnica.com/cars/2020/01/turn-
| by-turntables-how-...
|
| It showed up on HN some time ago.
| aidenn0 wrote:
| Maybe Etak? https://www.fastcompany.com/3047828/who-needs-gps-
| the-forgot...
| actionfromafar wrote:
| Bingo
| sebastianconcpt wrote:
| And the UI has that beautifully complex vibe that's the opposite
| of flat. Every atom of it is _very_ touchy-feely.
| stronglikedan wrote:
| More importantly, every component is _differently_ touchy
| feely, so that it can be easily used by touch alone.
| sebastianconcpt wrote:
| ...without forcing the user to look at what is touching to
| know what is touching and in which state it is (kinaesthetic
| communication)
| aidenn0 wrote:
| This has to be the closest to a joke-name that a real product
| has. I read "Electro Gyrocator" but I hear "Turbo Encabulator"
| dang wrote:
| Related:
|
| _Electro Gyro-Cator (1981)_ -
| https://news.ycombinator.com/item?id=10614058 - Nov 2015 (6
| comments)
| jetrink wrote:
| Another early inertial navigation system for cars was the Etak
| Navigator, which was originally released in 1985. The idea for
| the device was conceived onboard Nolan Bushnell's racing yacht in
| a conversation between Nolan and his navigator, Stan Honey. Stan,
| who was also an accomplished engineer, went on to found Etak with
| Nolan's financial backing. You can see the device in Chevy
| Chase's car early on in the 1991 film Nothing But Trouble.
|
| 1. https://www.fastcompany.com/3047828/who-needs-gps-the-
| forgot...
| yborg wrote:
| Worked on early auto navigation systems at Motorola in the
| early-90s, using differential wheel sensor data from the ABS
| system for dead-reckoning interpolation between fixes from the
| original SA-active GPS before the full constellation was
| deployed. This was a hard problem to solve with the technology
| of that era, and impossible at an economically viable price
| point. Our map database was on an original Red Book _single-
| speed_ CD qualified for automotive temperature range. It took
| minutes to plan a route.
|
| Sometimes the technology just isn't ready.
| okl wrote:
| A video showing the device in action:
| https://www.youtube.com/watch?v=hOqig8rixOU
___________________________________________________________________
(page generated 2023-01-31 23:01 UTC)