5 ms·

The question to me is why would someone want a faster Z. Normally people only view their GPS in 2D, granted elevation could be useful for GPS speedos and the l

The question to me is why would someone want a faster Z. Normally people only view their GPS in 2D, granted elevation could be useful for GPS speedos and the like, but when inside a car the barometer will lack precision. The Private Pilot (ie n00b of t3h pilots!111!) in me knows that its incredibly unlikely to have issues seeing many GPS sats when flying, and I wouldn't ever want a static source that wasn't outside. So I think this will be only a speed optomisation at most, however combined with GPS posistion and tempurature, such barometric data could no doubt be of use to weather forecasters who are trying to model incredibly localised patterns maybe?

pavel_lishin 14y ago
No matter what your screen is showing you, you are currently occupying three dimensions of space, and if you want an accurate representation of that without already knowing at least your rough location, you need to lock on to more satellites than you do if you already know approximately how high you are. At least, such is my limited understanding.
- XorNot 14y ago
  Also if I'm plummeting out of plane in the middle the night with no sense of position, then I'm not saying relying on my phone is a good idea but knowing when to pull my chute so I don't spend too much time in the stratosphere would be pretty handy. I mean I'm not saying it's likely but...luck favors the prepared right?
- TheAnimus 14y ago
  As I said I support faster GPS (my last line in the post). I think it might be a faster, data light alternative to the A-GPS thing, but I can't really see it narrowing it down that much? I'd have thought dual tuning GLONAS and GPS was better? After-all the error for these sensors will be vast depending on where you are. My understanding (may well have changed, I don't know) is that currently most work on one or the other, not both. A reason I am saying this is I remember the first time I flew a plane in Asia after learning in mild weathered UK I was getting challanging readings from my static source. As such I'm not sure how well it would work as an optomisation. I'm not saying its bad, I'm not saying it's not fun for geeks considering the no doubt low cost of this scale. But I still don't see the need for faster Z, as most smartphone users are on the terraferma?
ghshephard 14y ago
"The question to me is why would someone want a faster Z." Cyclists, Joggers - anybody who uses their iPhone for logging external activities is frustrated with how inaccurate the iPhone is for capturing Z. It's not completely useless, but it's not very precise.
- TheAnimus 14y ago
  I bought one of the handle bar mounts for my phone and have really rather accurate Z, this is also in London too, AFAIK the software isn't using map data to help either, but surely that would be a good way of doing it too. Archway Hill has always been accurate, even on my old Garmin thing. Again I think it is mostly for faster aqusistion, as i doubt how this will help anyone who isn't keeping their phone in a correct posistion for accurate sampling. These barometric sensors weren't that accurate 5-7 years ago when I played with them, I can't imagine them helping when in a pocket or waterproofed running strap / cycle case.
kordless 14y ago
GPS coordinates are calculated off what are known as psudoranges: http://en.wikipedia.org/wiki/Pseudorange http://en.wikipedia.org/wiki/Pseudorange. You can imagine these 'ranges' as a calculated distance to a given satellite. Knowing the altitude ahead of time allows you to calculate your 3D position faster because you don't need as many range samples, or satellites, to do accurate estimates of position.

pavel_lishin 14y ago

No matter what your screen is showing you, you are currently occupying three dimensions of space, and if you want an accurate representation of that without already knowing at least your rough location, you need to lock on to more satellites than you do if you already know approximately how high you are. At least, such is my limited understanding.

XorNot 14y ago
Also if I'm plummeting out of plane in the middle the night with no sense of position, then I'm not saying relying on my phone is a good idea but knowing when to pull my chute so I don't spend too much time in the stratosphere would be pretty handy. I mean I'm not saying it's likely but...luck favors the prepared right?
TheAnimus 14y ago
As I said I support faster GPS (my last line in the post). I think it might be a faster, data light alternative to the A-GPS thing, but I can't really see it narrowing it down that much? I'd have thought dual tuning GLONAS and GPS was better? After-all the error for these sensors will be vast depending on where you are. My understanding (may well have changed, I don't know) is that currently most work on one or the other, not both. A reason I am saying this is I remember the first time I flew a plane in Asia after learning in mild weathered UK I was getting challanging readings from my static source. As such I'm not sure how well it would work as an optomisation. I'm not saying its bad, I'm not saying it's not fun for geeks considering the no doubt low cost of this scale. But I still don't see the need for faster Z, as most smartphone users are on the terraferma?

ghshephard 14y ago

"The question to me is why would someone want a faster Z." Cyclists, Joggers - anybody who uses their iPhone for logging external activities is frustrated with how inaccurate the iPhone is for capturing Z. It's not completely useless, but it's not very precise.

TheAnimus 14y ago
I bought one of the handle bar mounts for my phone and have really rather accurate Z, this is also in London too, AFAIK the software isn't using map data to help either, but surely that would be a good way of doing it too. Archway Hill has always been accurate, even on my old Garmin thing. Again I think it is mostly for faster aqusistion, as i doubt how this will help anyone who isn't keeping their phone in a correct posistion for accurate sampling. These barometric sensors weren't that accurate 5-7 years ago when I played with them, I can't imagine them helping when in a pocket or waterproofed running strap / cycle case.

kordless 14y ago

GPS coordinates are calculated off what are known as psudoranges: http://en.wikipedia.org/wiki/Pseudorange http://en.wikipedia.org/wiki/Pseudorange. You can imagine these 'ranges' as a calculated distance to a given satellite. Knowing the altitude ahead of time allows you to calculate your 3D position faster because you don't need as many range samples, or satellites, to do accurate estimates of position.