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Apple Maps claims it's 29,905 miles away

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Re: Apple Maps claims it's 29,905 miles away

#31

Post by Liftyee »

monerozcash wrote: post #21

While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…

I wonder if it's using a compass and odometry (distance) with dead reckoning. A strange choice when GPS is available, but it would account for the map moving in the car's direction and it not changing locations when it moved without rolling (ferry).

Re: Apple Maps claims it's 29,905 miles away

#32

Post by stockresearcher »

monerozcash wrote: post #21

While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…

I had a Volvo XC90 that “jumped” off the interstate and onto a parallel mountain road east of Knoxville. It did its best to track along those roads and somehow made its way into North Carolina. But even when I was back in Chicago, it was still stuck in NC trying to find a way off those mountain roads. Dozens of on/off cycles did nothing. I disconnected the battery overnight and that didn’t work. At the next service appointment, the dealer had to do a full firmware reset to wipe the memory and get it working again.

It amazed me that Volvo programmed an SUV to disbelieve that it could ever actually leave a road.

Re: Apple Maps claims it's 29,905 miles away

#33

Post by technothrasher »

monerozcash wrote: post #21

While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…

I remember cars in the early 2000's doing this. Haven't seen that behavior in years.

Re: Apple Maps claims it's 29,905 miles away

#34

Post by bragr »

monerozcash wrote: post #21

While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…

My guess would be:

1. Car entered ferry, loses GPS

2. Car entered dead reconning mode used for tunnels and such

3. Car left ferry, acquired GPS

Then either:

4a. Location via dead reconning vasty disagreed with GPS because the car doesn't know about the ferry's movements, triggering some kind of failsafe.

Or:

4b. There's just a plain old bug in the condition to switch back to GPS and maybe people haven't noticed because you don't get as badly desynced in a tunnel.

>the car must have a pretty good dead reckoning system

Yeah all the pieces are there: accelerometers and gyros for stability control, compass for navigation, and the wheel speed sensors give you exact distance traveled.

Re: Apple Maps claims it's 29,905 miles away

#35

Post by billyjmc »

Liftyee wrote: post #31
monerozcash wrote: post #21

While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…

I wonder if it's using a compass and odometry (distance) with dead reckoning. A strange choice when GPS is available, but it would account for the map moving in the car's direction and it not changing locations when it moved without rolling (ferry).

Almost certainly. GPS is not only easily jammed, but easily spoofed. If the car believed GPS instead of its own eyes, so to speak, then there’s significant potential that you’d see glitches more often. It could also be something of a safety risk when using its self-driving capabilities.

Re: Apple Maps claims it's 29,905 miles away

#36

Post by kijin »

stockresearcher wrote: post #32
monerozcash wrote: post #21

While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…

I had a Volvo XC90 that “jumped” off the interstate and onto a parallel mountain road east of Knoxville. It did its best to track along those roads and somehow made its way into North Carolina. But even when I was back in Chicago, it was still stuck in NC trying to find a way off those mountain roads. Dozens of on/off cycles did nothing. I disconnected the battery overnight and that didn’t work. At the next service a…

My dad used to have a crappy aftermarket GPS in his car that did the same thing. It would get lost dozens of miles away, and then hundreds of miles away.

The explanation I found online at the time was that a GPS receiver needs to download data about the exact orbits of all GPS satellites from time to time. Satellites slowly lose altitude and change their orbits. Up-to-date information is constantly broadcasted by every satellite, but it takes about 15 minutes for a device on the ground to download this dataset.

Most GPS devices do this automatically whenever they get the chance. But if your GPS is somehow unable to stay online for 15 consecutive minutes (bad firmware, faulty memory, tunnels, underground parking lots, etc), it will be relying on increasingly outdated info and drift far off its actual location.

Re: Apple Maps claims it's 29,905 miles away

#38

Post by bragr »

Liftyee wrote: post #31
monerozcash wrote: post #21

While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…

I wonder if it's using a compass and odometry (distance) with dead reckoning. A strange choice when GPS is available, but it would account for the map moving in the car's direction and it not changing locations when it moved without rolling (ferry).

In addition to sibling's comments about jamming and self driving safety, there are many driving situations where there is no or poor GPS reception: tunnels, double deck bridges, double deck freeways, underpasses, urban canyons, actual canyons, etc. Also regional problems. The GPS constellation is in a 55° inclination, so if you are north of ~55N, or south of ~55S, you need a clear view of the southern/northern sky, respectfully, for reception, since there will be no overhead satellites.

Re: Apple Maps claims it's 29,905 miles away

#39

Post by meindnoch »

hyperpape wrote: post #14
pushedx wrote: post #12

It is easily 29,905 road miles away. If you put all of your blood vessels end to end they would go to the moon and back.

Being a little bit clever can lead you to make some pretty bad mistakes. Yes, the distance according to roads can be different from the distance as the crow flies. No, it cannot realistically be 10x the distance when the crow's distance is 2500 miles.

But what if you count the distance of going in and out of each tiny crack on the road surface?

Re: Apple Maps claims it's 29,905 miles away

#40

Post by doubled112 »

stockresearcher wrote: post #32
monerozcash wrote: post #21

While we're on the subject of maps-related bugs, I was recently borrowing a new Tesla Model Y and took it on a RORO ferry. After the crossing, the car’s GPS was convinced I was still at the port where I had departed from. I restarted it a couple of times, but nothing. I drove off using Waze on my phone instead of the car's navigation. The map on the car kept moving relative to the direction I was driving, so the navi…

I had a Volvo XC90 that “jumped” off the interstate and onto a parallel mountain road east of Knoxville. It did its best to track along those roads and somehow made its way into North Carolina. But even when I was back in Chicago, it was still stuck in NC trying to find a way off those mountain roads. Dozens of on/off cycles did nothing. I disconnected the battery overnight and that didn’t work. At the next service a…

Last summer traveling down a rural road in southwestern Ontario, Apple maps told me to return to the route. We hadn't turned in 10 kilometers, but it was showing that we were 200 meters into a cornfield.

I don't think I could have ended up there if I tried in the Golf we were in. Nice try.

My kids thought it was the funniest thing, but it's a good technology lesson.

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