With regards to a M8N GPS connected to a APM 2.8, is it normal for it to be wildly moving around while the Quad is stationary on the ground? On Mission planner it shows the Quad moving all over the place, around +- 20 meters to where it is situated. The sat count is around 7 to 8 and the HDOP value is 2.5. It there anyway that the accuracy of the GPS can be improved. Also, when i switch into the land mode after a flight, the quad starts descending, but then drifts suddenly to the right. Luckily it hasn't crashed yet as i have taken manual control of the craft before it hits the ground. I don't really want to try the return to launch mode if the GPS is showing the Quad in the wrong place, and it cannot land itself. Any suggestions to fix these issues?
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very much so since I am not sure how much our [the US] GPS sats cover that part of the planet.
I use this awesome tool to get an idea of what I can expect on any given day or time.
http://www.trimble.com/GNSSPlanningOnline/#/Settings
but I think it only works in IE as it uses silverlight.
Have you tried disconnecting your telemetry module and hovering in position hold etc. New GPS and glonass channels are all over the place including 1.2g as of the next few months, the extra satellites give better HDOP but make things a lot fussier, especially when it comes to harmonics carrying data.
Normal GPS positioning is plus or minus 5 meters of accuracy at best. Less than 10 Satellites is common.
Less than 10 on a Neo-6m or Neo-7m or LEA-6H is common, Less than 10 on a M8N is NOT common especially with that high of a HDOP
It is normal whilst it is warming up to mover all over the place, but that HDOP and sat count is horrible for a m8n module. On a cold boot, here is south Texas, it normally takes a good few minutes to get a steady lock but when it does I normally get 20+ sats and a HDOP of around .8 or less.
Pics would help as it sounds like you have your GPS too close to something creating EMF and degrading the signal. Also you did not provide exactly which module it is so without pics and knowing exactly which module you have [hopefully not a BN800 as they tend to suck] there really can be few suggestions on how to fix something without knowing what there is to fix.
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