Mini 2 Tracking Issues

High Detail is very detrimental to battery life. 

twolpert said:

I have not used the M2 in some time. I am unable to verify the level of detail in the activity at the standard logging interval.

For your information: in the "standard" activity logging mode, the activity point logging interval matches the tracking point logging interval. So if you set the tracking interval to 10 minutes, you'll also get a couple of activity points logged every ten minutes. I say "a couple", because activity logging seems to work according to the following logic flow:

1. Wait for the tracking interval timer to expire
2. Turn on the GPS receiver
3. Start logging activity points using the "high detail" logic (i.e. more frequently the more squirrely your path is)
4. Continue recording activity points until the inReach (Iridium) tracking point update message has been sent
5. Turn off the GPS receiver
6. Rinse, repeat

Because of item #4, you'll probably get multiple activity points logged per tracking point, depending on the sky view conditions and the time it takes to ping a satellite.

MushyTomato said:

seems to work according to the following logic flow:

1. Wait for the tracking interval timer to expire
2. Turn on the GPS receiver
3. Start logging activity points using the "high detail" logic (i.e. more frequently the more squirrely your path is)
4. Continue recording activity points until the inReach (Iridium) tracking point update message has been sent
5. Turn off the GPS receiver
6. Rinse, repeat

That matches with my experience as well.  It seems that High Detail is just an extension of this where the GPS stack is active and there are more/continuous Activity logging points.  However those extra points aren't sent over Iridium updates (AFAIK), but rather via a sync over a conventional network. Thing is, it sure *seems* like the coalescing of the Activity points is somehow tied to the Iridium egg timer rather than being a completely separate mechanism. I find it suspect that I keep losing my final ~10 mins or so of Activity tracks, which happens to be the Iridium update interval.  Could just be coincidence, but something is definitely whacked when you stop tracking.  Closure and finalizing the track(s) needs work on the M2.

Regardless, I'm beginning to hate my M2, because it's a step backwards. I will probably go back to my Explorer+ and add back the extra ounces.

At the risk of sounding like I am ranting, here is another braindead thing about the M2...  If it can't acquire GPS at the moment the tracking interval expires and the Iridium stack wakes up, it just skips that tracking point. On the surface that might make sense. However, if you have been in high detail mode there is a rich log of points it could grab from to send a most recent GPS coordinate update from. It seems like it will only add the activity logging points if they happen to be within the same minute as the egg timer going off.

So for example, I went on a 1 hour trip with the tracking interval set to 10 minutes.  That Mapshare track, only had 3 point on it, because it failed to acquire GPS 50% of the time when it woke up to send over Iridium.  However, I was in High Detail Mode and the Activity track was fully populated and relatively precise (albeit truncated). It just so happened that it couldn't acquire signal in the exact minute that it woke up (several times).  But there was all this data, just sitting there, from 1-2 minutes previous where GPS was acquired, that it could have chosen a point from....  That would provide a much better Mapshare track, and it doesn't require sending anymore data than it otherwise would of, had GPS been acquired.  Honestly, it seems like the engineers and/or product specification folks working on the M2 have no common sense, or real world experience with their own product...

Edit:  Also, if it's contact with Iridium that can't be established, rather than GPS, it should still be trying to satisfy the trackpoint frequency from the data it has. The points are timestamped.  I.e. Users care about the there tracks being accurate and up to date as possible, not just what happens when a timer expires...

I can't say one way or another about the clustering of activity points in high detail mode. It IS true that that activity points are NOT sent over the Iridium network. You must sync to get these to web site. 

That is no different than it has ever been. These "activity points" are the same as the old "logged track points". it's just another new name designed to confuse you.

Understood.  It could just be that the Explorer+ was better at acquiring GPS and Iridium, so the issue was masked more.  But again, that was 10 year old tech.  Expecting it to have advanced in a decade.  Simple changes in algorithm could go a long ways here...

Both M1 and M2 are notorious for being slow to acquire in good conditions. And completely unable to acquire in challenging conditions. I suspect that the f/w is wise to just SKIP sent points when the device fails to acquire in a reasonable amount of time. Continuing to try is probably going to fail - and is going to suck battery.

The behavior you observed is almost certainly due to failure to acquire. Once ANY iR device tries to send something, it keeps trying and trying and trying until it succeeds. This is another giant batter suck - but reliable transmission is a requirement. Note that points are (or should be - can't say I've tried it lately) timestamped with the time they were generated, not the time they were successfully sent via the Iridium network.

twolpert said:

. I suspect that the f/w is wise to just SKIP sent points when the device fails to acquire in a reasonable amount of time. Continuing to try is probably going to fail - and is going to suck battery.

I agree, but if it's already sucking battery in high detail mode, and if it already has the data, then use it...  That's all I'm saying.  Seems braindead not to.   Yes points are indeed timestamped correctly.

The legacy devices were much better about acquiring than the M1/M2. IIRC, they behaved like the M1 with regard to control over the "logged point" interval. 

Hard to say about iR communication. There are strict limits on transmit power. Would not be surprised learn that the legacy device and M1/M2 use the same iR modem chip. Biggest variation would likely be in the antenna design.

Do note that the legacy devices were designed and built (originally) by DeLorme. DeLorme was 100% focused on back country use and safety. While Garmin pays attention to those things, sometimes I think their efforts are diluted by attempts to bring the iR devices into their handheld recreational ecosystem. In the extreme, this results in devices like the 66i (which you can at least use in the back country) and the Montana 7x0i (which is so large and heavy that, IMO, it's restricted to in-vehicle use).

Finally, note that the M1 and M2 are transition devices. That is, not real members of the Garmin ecosystem but not DeLorme either.