3 ms·

> Presumably these farms are out in the middle of nowhere and so that's why they can't do the same thing and need a satellite-based augmentation instead. Easil

> Presumably these farms are out in the middle of nowhere and so that's why they can't do the same thing and need a satellite-based augmentation instead. Easily maybe. I can’t see any reason someone can’t take a stationary GPS enabled device and use that to broadcast the differential between received location and actual location. Probably could do it for less than $20 in equipment. Add multiple units and get triangulation for free.

shagie 3y ago
Australia has a reasonable amount of yearly drift. It currently moves at about 6.8cm (2.7in) per year. That is enough movement that it can throw off purely GPS solutions. https://www.australiangeographic.com.au/topics/science-environment/2017/02/how-gps-keeps-up-with-australias-continental-drift/ https://www.australiangeographic.com.au/topics/science-envir... > ... > But two important things have happened since then. Australia has moved about 1.6 metres northeast, effectively moving the location of mapped features and their associated GDA94 coordinates. > At the same time, positioning technology has evolved considerably. By 2020, Australia will have moved by 1.8 metres and many of us will own devices that could pinpoint locations with accuracy as small as, well, a smartphone. With real-time access to precise satellite positioning at our fingertips, we’ll notice discrepancies with GDA94-mapped features. > Imagine the confusion if a driverless car can determine its coordinates with (say) decimetre accuracy, in the GNSS datum, but the stored map features were referenced to our old datum GDA94 and and were nearly two metres different. That’s probably not even in the same lane.
- myself248 3y ago
  As I understand it, RTK nulls that out. If your RTK base is fixed to the landmass that's moving, your rover positions will move right along with it. So a farmer with an RTK base stuck atop their silo or whatever should be fine.

shagie 3y ago

Australia has a reasonable amount of yearly drift. It currently moves at about 6.8cm (2.7in) per year. That is enough movement that it can throw off purely GPS solutions. https://www.australiangeographic.com.au/topics/science-environment/2017/02/how-gps-keeps-up-with-australias-continental-drift/ https://www.australiangeographic.com.au/topics/science-envir... > ... > But two important things have happened since then. Australia has moved about 1.6 metres northeast, effectively moving the location of mapped features and their associated GDA94 coordinates. > At the same time, positioning technology has evolved considerably. By 2020, Australia will have moved by 1.8 metres and many of us will own devices that could pinpoint locations with accuracy as small as, well, a smartphone. With real-time access to precise satellite positioning at our fingertips, we’ll notice discrepancies with GDA94-mapped features. > Imagine the confusion if a driverless car can determine its coordinates with (say) decimetre accuracy, in the GNSS datum, but the stored map features were referenced to our old datum GDA94 and and were nearly two metres different. That’s probably not even in the same lane.

myself248 3y ago
As I understand it, RTK nulls that out. If your RTK base is fixed to the landmass that's moving, your rover positions will move right along with it. So a farmer with an RTK base stuck atop their silo or whatever should be fine.