RS246.com Forum :: The World's #1 Audi R, S and RS Enthusiast Community

I'm still trying to find out if my Sat Nav plus is set up correctly.

In map mode, especially in 50m resolution, the cursor marking my position clearly 'lags' behind the car's actual position. For example when I pass an intersection, the cursor show that the car is still several meters before the intersection.

However this does not prevent navigation which works fine.

Is this normal operation?

If not, please can any A4, S4 or RS4 owner give me some data from their system?

To do this you need to be in the Navigation screen (where the "start guidance" menu option appears.

Press the "AS" and "down arrow" buttons simultaneously. This will show the comms screen. The press the right hand knob twice to show the software version screen. Now press the "flag" button to show the wheel setting screen.

Please could you let me know what the two numbers shown are, and also what tyres you have?

TIA,
Dave

SatNav only has positional precision down to around 30 metres (10 metres at best). The exact precision depends on how many satellites it is taking information from at that time (between 4 and 9).

Consequently I don't think your seeing anything out of the ordinary.

One thought though. Have you cut the speed sensor wire to allow tv display on the move ?
If you do this will affect the position too, as the SatNav uses this to interpolate your present position since its last reported location.

JohnW wrote:SatNav only has positional precision down to around 30 metres (10 metres at best). The exact precision depends on how many satellites it is taking information from at that time (between 4 and 9).

.

I was thinking about this over the weekend. My Origin B2 takes time to register the correct speed, usually under reasonable acceleration, but also know exactly where the cameras are. If it was only accurate to 10, 20, or 30 metres, how does it tell me the exact distance in metres until the camera?
My nav always seems to be on the button, but I have not managed to upgrade the firmware yet to show 50m resolution.

Cheers

Ben

Correction, the figures I gave were for FEET, not metres.
The normal accuracy attainable by a GPS in SPS mode
is 4 metres in 3D, or 2.5 metres in the horizontal plane.
Appologies for that.


The countdown bars on the display are in 10metre steps.
10 metres is only 33 feet, or roughly 2 cars lengths.

At 30 mph you will cover roughly 13.5 metres a second,
so would you really notice if it was out by say 10 metres
when travelling at 30mph ?

Now the techie bit:
As I said the exact resolution is dependent on how many satellites are registered and providing data at that time. Measurements are based on the geometric dilution (spacial seperation) of the satellites. In simple terms the more they are spread out the better the accuracy. This is why the satnav would like more than 4 to choose from if possible.

Cheers,
John. (working with a navigation system at present )

Dave AKA Dippy, I have PM'd you 3 times now! Do you hate me or somethin'!, Have I done somethin' to offend you!
















































Only Jokin' but still need help with that Sat Nav etc.

Stevo

Ahh, that makes more sense
You're right, 1 second is not a lot, even less when driving at 50MPH which is the speed most of my regular cameras are set around.

Cheers

Ben