Gpsmap 60c - Track Logging Interval

[+hardwire]

I was trying to determine what the AUTO record method frequency is related to for logging of track points for options NORMAL, MORE OFTEN, MOST OFTEN.... are they related to distance or time, both, etc... Thanks

[coureur des bois]

I was trying to determine what the AUTO record method frequency is related to for logging of track points for options NORMAL, MORE OFTEN, MOST OFTEN.... are they related to distance or time, both, etc... Thanks

NORMAL, MORE OFTEN, MOST OFTEN ...

this specify what you choose in the settings

 

they are related to what you choose (distance or time) If you don't chose, the GPS choose from some algorithm fixed by programmers (AUTO)

 

NORMAL, MORE OFTEN, MOST OFTEN fix the frequency, determined by the distance or by the duration

[peter]

I believe the frequency of trackpoints in AUTO mode is mainly related to the predictability of your movement. AFAICT, the firmware looks at your previous trackpoints and uses them to define the line along which you're currently moving. Then it compares your current position to that line and puts down another trackpoint if you're over some threshold distance (like 25m) away from the line. Therefore you'll get more trackpoints when going around a corner and very few when you're driving down a straight highway. Trackpoints may also be created when there's a significant change in speed (or altitude esp. for units with barometric sensors).

Changing from NORMAL to MORE OFTEN or MOST OFTEN will reduce the threshold distance and therefore increase the frequency of creating new trackpoints.

[+hardwire]

Well that explains why it has "groups" of waypoints on my tracks when I use AUTO... Thanks!

[rickertk]

If the 60C is anything like the VistaC I have, or the 60CS I've played with, then "Normal", "Most Often", etc. only appear in conjunction with the "Auto" mode of recording trackpoints. With either distance or time selected, you explicitly enter the time or distance interval between points.

 

Keith

[+hardwire]

If the 60C is anything like the VistaC I have, or the 60CS I've played with, then "Normal", "Most Often", etc. only appear in conjunction with the "Auto" mode of recording trackpoints. With either distance or time selected, you explicitly enter the time or distance interval between points.

 

Keith

Yes, that was kinda my question ... Distance and time worked as expected, but I could not figure out what the AUTO pattern was doing... I went out this evening on a track and it looks like what Peter had indicated related to distance off a current course line... Thanks

[+BlueDeuce]

I was under the impression it was just a sampling rate, meaning that it would record the current positon more or less often .

[+hardwire]

I was under the impression it was just a sampling rate, meaning that it would record the current positon more or less often .

It doesn't seem to be just a sampling rate because it kept changing, which is why I was getting confused as to what it really was doing.... on this evenings track, it would generate 3 or 4 trackpoints on a every 90 degree corner then only periodically as the street I walked curves.. then everytime I would stop walking it created 2 points close together.... I think Peter has it figured out....

 

Here is a jpg showing the MOST OFTEN option... the close blue dots are when my dog would stop or slow down... the track runs on the sidwalk...

 

Edited February 24, 2005 by hardwire