Recalc

Kenny Rodkiss

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While on holls this year I encountered a few problems with Nav2.

On tight winding mountain passes where the road almost doubles back on itself, the unit would say either off route or would imediatley say recallculating and this is with recallculate option turned off.

This was on routes made with the unit, to go from A to B using custom road preferences and favouring smaller roads.
Sometimes it would recalc a route in the opposite direction to which I was just travelling?

It seemed to think that I was going the wrong way on the route, with road twisting almost back on itself on numerous turns.

I do not understand why it was recalulating my route when I have this option turned off.


Any ideas? :confused:
 
Check to make sure that you are using the latest version of the software for the GPS itself (nothing to do with the maps). I encountered this problem when doing the testing for the 2610 several years ago, Garmin worked on it and solved it in the later releases of the software.

It is, as you have guessed, caused by the GPSR losing track of where it is on the road. My guess is that you not only were riding on very twisty roads with mountain switchbacks, but you also had fairly heavy tree canopy above you, or perhaps a mountain on one side of you that was blocking the GPSRs view of much of the satellite constellation. Under such conditions - tight switchbacks and a restricted view of the satellite constellation - the GPSR can easily get confused because it is just 'hanging on by its fingernails', so to speak, to 3 or 4 satellites - not the normal 12 satellites that you would get in a flat area. Because it is only picking up a bare minimum of satellites, it can't resolve its position as accurately or quickly as it could if it was seeing 12 satellites.

I do a lot of mountain riding, and use a 2650 (same as a 2610, but with a direct speedsensor connection and internal gyros to track yaw and bank). When the 2650 loses its view of the satellites, it reverts to the speedsensor input and the gyro system for track guidance.

Michael
 
Hmmmmmmmmm.

Yep I can understand that it may have been doing its best with a poor signal but why was it recalculating the route rather than just telling me I was off route and leave it at that, as it usually does?

Still a brill bit of kit though.
 
Kenny Rodkiss said:
...why was it recalculating the route rather than just telling me I was off route and leave it at that, as it usually does?

Because it thought you were off the roadway, not simply on a different roadway that was off the route you had designated. In other words, it figured you had gone into the weeds.

Michael
 


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