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There is currently some kind of geomagnetic storm which is causing a lot of GPS tracks to be offset over the past few days. It's all over the running/cycling fo

by jerlam 4y ago

There is currently some kind of geomagnetic storm which is causing a lot of GPS tracks to be offset over the past few days. It's all over the running/cycling forums. Could be related, here's an example: https://old.reddit.com/r/Garmin/comments/vo17e2/the_magnetic_storm_is_over_my_track_is_still_all/ https://old.reddit.com/r/Garmin/comments/vo17e2/the_magnetic...

walrus01 4y ago
It is worth noting however that the size, power consumption and antenna precision of a watch-sized or bicycle computer size GPS(+glonass, Galileo, beidou, qzss) receiver is considerably smaller than what should be in these vehicles. I have not seen any mention of GPS service degradation in hobbyist drone enthusiast groups over the last week, some of whom use quite small GPS modules with serial connection to the flight controller for automated signal lost return to home features and such.
- toomuchtodo 4y ago
  I would find it odd if they were not using precise positioning using local reference stations broadcasting corrections over IP or RF. EDIT: Appears GPS/IMU/LIDAR is sufficient, my mistake. TIL.
  - jeffbee 4y ago
    They're almost certainly using dead reckoning with wheel rotation sensors to get the precision they need in an urban environment where radios are kinda trash.
    - walrus01 4y ago
      I would think zero wheel rotation sensors and just LIDAR, which cruise uses extensively.
    - deleted 4y ago
      [deleted]
    - rblatz 4y ago
      Tesla’s also use dead reckoning when GPS is lost. It’s way more accurate than I would have guessed. My GPS antenna was out for over a week and the map was only about 100ft off.
tjohns 4y ago
NOAA doesn't list any meaningful geomagnetic storms right now: https://www.swpc.noaa.gov/communities/space-weather-enthusiasts https://www.swpc.noaa.gov/communities/space-weather-enthusia... But that aside, I'd really hope that these cars are using professional WAAS-capable GPS receivers. Short of a major X-class flare which knocks out the WAAS geostationary satellites, the entire point of the system is to correct for these kinds of disturbances to the GPS signals.
- Natsu 4y ago
  Why does this make me wonder if something is going on with GPS due to the war in Ukraine?
  - mh- 4y ago
    EDIT: the following is incorrect per a reply below. Will leave the original comment below. --- That was going to be my hypothesis. GPS resolution can be reduced in a conflict area. I'll defer to someone with actual knowledge to add more info. :)
    - TaylorAlexander 4y ago
      I believe the government promised not to ever reduce GPS resolution some 15 years ago, and new satellites supposedly do not even have the ability to do so.
      - mh- 4y ago
        TIL, apologies for the misinformation! Will correct my comment if it's still in the edit window
      - HHC-Hunter 4y ago
        Oh my sweet summer child.
        RajT88 4y ago
pj_mukh 4y ago
Highly doubt they'd be using GPS for anything more than putting them in the right neighborhood. Edit: Looks like someone ex-Cruise confirmed this ITT
- KennyBlanken 4y ago
  That's not what the comment said. They said the system can tolerate degradation / loss of GPS data for periods of time, in certain circumstances: https://news.ycombinator.com/item?id=31940167 https://news.ycombinator.com/item?id=31940167 > Fine localization should be able to resolve without GNSS input (with caveats) and there are specific tested requirements to be able to tolerate a certain number of minutes of outage even in the absence of LIDAR before position accuracy degrades beyond acceptable limits.
bmicraft 4y ago
People in that thread are reporting a problem with gps + glonass while galileo on the same frequency as gps is fine.
- aqfamnzc 4y ago
  Could it be using a different protocol or CRC system that's more resistant to that type of issue perhaps? There must be some difference, otherwise it would just be more GPS, right?
TedShiller 4y ago
You're very optimistic
bee_rider 4y ago
It couldn't possibly be GPS, right? Networks are unreliable, the cars must be able to reach a safe state if the network drops out. They appear to have stopped in the road. If these cars can't safely navigate their way to the side of the road using local sensors, they are wildly, hilariously unsuited for autonomous operation. > at least a dozen autonomous Chevrolet Bolts from GM Cruise Automation were spotted blocking the intersection at Gough Street and Fulton Street for a couple of hours, according to reddit user seansinha. There must be something weird about that intersection that is causing a bug.
- yupper32 4y ago
  > If these cars can't safely navigate their way to the side of the road using local sensors, they are wildly, hilariously unsuited for autonomous operation. You are a lot more confident than me that this isn't the case.
  - bee_rider 4y ago
    Or I could be pessimistic about GPS -- these things are, albeit in limited numbers, on the road and actually being used by customers, right? I guess I'm surprised GPS is so reliable that this isn't a widespread, constant issue, if this is the normal "I lost GPS" behavior.
    - carlmr 4y ago
      It could be a middle ground kind of thing. The cars have to trust something. For position you have GPS + some interpolation based on your movement sensors + some buildings/streets and maps (also unreliable since construction etc changes a lot, a lot of buildings and intersections look the same, etc). Computers are very far away from understanding where they are from context alone. Hell most humans don't know where they are. So if you have a short GPS outage they will be able to continue navigating due to other sensors, but the longer the GPS outage/issues persist the more unlikely it is that they still know where they are. There should definitely be a safety to drive to the side of the road and wait though.
sorenjan 4y ago
I doubt it has anything to do with any geomagnetic storm, the issue seems to only affect Garmin devices.
- deleted 4y ago
  [deleted]
infairverona 4y ago
That is most definitely not it, these vehicles have localization modules that rely on lidar point cloud matching, gps is generally only used for bootstrapping that process but is technically not even needed.
raverbashing 4y ago
GPSs can and will be taken offline sometimes (in a region) due to military exercises, tests etc This happens with a certain frequency in aviation Relying purely on GPS (for self driving) won't work.
CTDOCodebases 4y ago
People were responding that switching from Glonass to Galileo fixed it. Could it be sabotage?
- nosianu 4y ago
  > Could it be sabotage? Given that even Russian pilots in Ukraine have been found to be using GPS, it looks like that would not even be necessary. https://www.globaldefensecorp.com/2022/06/21/exposed-captured-russian-pilots-admit-that-russian-air-force-distributed-garmin-gps-and-pronebo-mobile-app-to-navigate-in-ukraine/ https://www.globaldefensecorp.com/2022/06/21/exposed-capture...
belter 4y ago
Are you telling me all these fleet of vehicles can be defeated with a GPS Jammer? https://www.jammer-store.com/gj6-all-civil-gps-signal-jammer-blocker.html https://www.jammer-store.com/gj6-all-civil-gps-signal-jammer...

by jerlam 4y ago

walrus01 4y ago

It is worth noting however that the size, power consumption and antenna precision of a watch-sized or bicycle computer size GPS(+glonass, Galileo, beidou, qzss) receiver is considerably smaller than what should be in these vehicles. I have not seen any mention of GPS service degradation in hobbyist drone enthusiast groups over the last week, some of whom use quite small GPS modules with serial connection to the flight controller for automated signal lost return to home features and such.

toomuchtodo 4y ago
I would find it odd if they were not using precise positioning using local reference stations broadcasting corrections over IP or RF. EDIT: Appears GPS/IMU/LIDAR is sufficient, my mistake. TIL.
- jeffbee 4y ago
  They're almost certainly using dead reckoning with wheel rotation sensors to get the precision they need in an urban environment where radios are kinda trash.
  - walrus01 4y ago
    I would think zero wheel rotation sensors and just LIDAR, which cruise uses extensively.
  - deleted 4y ago
    [deleted]
  - rblatz 4y ago
    Tesla’s also use dead reckoning when GPS is lost. It’s way more accurate than I would have guessed. My GPS antenna was out for over a week and the map was only about 100ft off.

tjohns 4y ago

NOAA doesn't list any meaningful geomagnetic storms right now: https://www.swpc.noaa.gov/communities/space-weather-enthusiasts https://www.swpc.noaa.gov/communities/space-weather-enthusia... But that aside, I'd really hope that these cars are using professional WAAS-capable GPS receivers. Short of a major X-class flare which knocks out the WAAS geostationary satellites, the entire point of the system is to correct for these kinds of disturbances to the GPS signals.

Natsu 4y ago
Why does this make me wonder if something is going on with GPS due to the war in Ukraine?
- mh- 4y ago
  EDIT: the following is incorrect per a reply below. Will leave the original comment below. --- That was going to be my hypothesis. GPS resolution can be reduced in a conflict area. I'll defer to someone with actual knowledge to add more info. :)
  - TaylorAlexander 4y ago
    I believe the government promised not to ever reduce GPS resolution some 15 years ago, and new satellites supposedly do not even have the ability to do so.
    - mh- 4y ago
      TIL, apologies for the misinformation! Will correct my comment if it's still in the edit window
    - HHC-Hunter 4y ago
      Oh my sweet summer child.
      - RajT88 4y ago

pj_mukh 4y ago

Highly doubt they'd be using GPS for anything more than putting them in the right neighborhood. Edit: Looks like someone ex-Cruise confirmed this ITT

KennyBlanken 4y ago
That's not what the comment said. They said the system can tolerate degradation / loss of GPS data for periods of time, in certain circumstances: https://news.ycombinator.com/item?id=31940167 https://news.ycombinator.com/item?id=31940167 > Fine localization should be able to resolve without GNSS input (with caveats) and there are specific tested requirements to be able to tolerate a certain number of minutes of outage even in the absence of LIDAR before position accuracy degrades beyond acceptable limits.

bmicraft 4y ago

People in that thread are reporting a problem with gps + glonass while galileo on the same frequency as gps is fine.

aqfamnzc 4y ago
Could it be using a different protocol or CRC system that's more resistant to that type of issue perhaps? There must be some difference, otherwise it would just be more GPS, right?

TedShiller 4y ago

You're very optimistic

bee_rider 4y ago

It couldn't possibly be GPS, right? Networks are unreliable, the cars must be able to reach a safe state if the network drops out. They appear to have stopped in the road. If these cars can't safely navigate their way to the side of the road using local sensors, they are wildly, hilariously unsuited for autonomous operation. > at least a dozen autonomous Chevrolet Bolts from GM Cruise Automation were spotted blocking the intersection at Gough Street and Fulton Street for a couple of hours, according to reddit user seansinha. There must be something weird about that intersection that is causing a bug.

yupper32 4y ago
> If these cars can't safely navigate their way to the side of the road using local sensors, they are wildly, hilariously unsuited for autonomous operation. You are a lot more confident than me that this isn't the case.
- bee_rider 4y ago
  Or I could be pessimistic about GPS -- these things are, albeit in limited numbers, on the road and actually being used by customers, right? I guess I'm surprised GPS is so reliable that this isn't a widespread, constant issue, if this is the normal "I lost GPS" behavior.
  - carlmr 4y ago
    It could be a middle ground kind of thing. The cars have to trust something. For position you have GPS + some interpolation based on your movement sensors + some buildings/streets and maps (also unreliable since construction etc changes a lot, a lot of buildings and intersections look the same, etc). Computers are very far away from understanding where they are from context alone. Hell most humans don't know where they are. So if you have a short GPS outage they will be able to continue navigating due to other sensors, but the longer the GPS outage/issues persist the more unlikely it is that they still know where they are. There should definitely be a safety to drive to the side of the road and wait though.

sorenjan 4y ago

I doubt it has anything to do with any geomagnetic storm, the issue seems to only affect Garmin devices.

deleted 4y ago
[deleted]

infairverona 4y ago

That is most definitely not it, these vehicles have localization modules that rely on lidar point cloud matching, gps is generally only used for bootstrapping that process but is technically not even needed.

raverbashing 4y ago

GPSs can and will be taken offline sometimes (in a region) due to military exercises, tests etc This happens with a certain frequency in aviation Relying purely on GPS (for self driving) won't work.

CTDOCodebases 4y ago

People were responding that switching from Glonass to Galileo fixed it. Could it be sabotage?

nosianu 4y ago
> Could it be sabotage? Given that even Russian pilots in Ukraine have been found to be using GPS, it looks like that would not even be necessary. https://www.globaldefensecorp.com/2022/06/21/exposed-captured-russian-pilots-admit-that-russian-air-force-distributed-garmin-gps-and-pronebo-mobile-app-to-navigate-in-ukraine/ https://www.globaldefensecorp.com/2022/06/21/exposed-capture...

belter 4y ago

Are you telling me all these fleet of vehicles can be defeated with a GPS Jammer? https://www.jammer-store.com/gj6-all-civil-gps-signal-jammer-blocker.html https://www.jammer-store.com/gj6-all-civil-gps-signal-jammer...