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Sprint/Rally Question - using GPS on multiple 'tracks'

Posted: Tue Mar 13, 2012 10:33 pm
by geefin
A newbie question here. I recently ran the LapTimer on a rally stage, very nice and straightforward to program the standing start/splits/flying finish into a 'track' (all be it 'stage' in this instance), and for the morning runs it was great, a real time saver and good indication of progress. So we had the four points in the Stage 1 track map.

In the afternoon, the stage was reversed (so flying finish became standing start and vice versa). I tried to create new GPS points but got the message that there was already a GPS point there and so another couldn't be added. To get through the day, I manually moved the GPS points from Stage 1, into Stage 2 and this worked.

However, given this is a regular occurence (stages being reversed in the afternoon), is there a better way I could have gone about this (ie. programming the stages before the event). Is it possible to use GPS points in multiple (overlapping) tracks?

I'm presuming there is some way to go about this as many racetracks have different configurations yet utilise the same start/finish, any help will be gratefully appreciated! :)

Cheers,
Graeme.

Re: Sprint/Rally Question - using GPS on multiple 'tracks'

Posted: Tue Mar 13, 2012 11:34 pm
by Harry
Hi,

O.k., that's a nice 'track programming question'.

In general, I discourage defining overlapping tracks. Reason is, things get complicated, and some trigger combinations can yield undefined results. E.g. if you have two triggers near each other, both including 'Go', which one should LapTimer choose?

So the general solution for having two overlapping track configurations is storing the track set (e.g. on my server) and loading them alternating. The good news is loading / unloading track sets preserve laps recorded, what is changed, are simply the POIs / triggers sitting in LapTimer's database.

In case you don't want to store the configurations on my server as they are private / temporary, you can store them on your device using the following trick: define the first track set (name is A2B); press 'Certify' to send this track set to me; change the email address to your address and send it out (to yourself); afterwards, define the second track set (name it B2A), and follow the above steps again. Having this done, you find two track sets in your inbox. Long-pressing either of theses track sets (A2B.hpoil and B2A.hpoil) will allow importing this track set into LapTimer again.

But getting back to trigger programming capabilities: as long as you know what you do :-) (i.e. understand the trigger semantics), you can define both A2B and B2A at the same time. As long as LapTimer laps, it will ignore 'Go' triggers. While not lapping, 'Stop' triggers are ignored. So you can define the following triggers and get LapTimer automatically switching track and working both ways:
  • In position A, define a 'Go' trigger and associate it to a track configuration A2B
    In position A, define a 'Stop' trigger and associate it to a track configuration B2A
    In position B, define a 'Go' trigger and associate it to a track configuration B2A
    In position B, define a 'Stop' trigger and associate it to a track configuration A2B
To work around timing issues (you pass the stop trigger and LapTimer immediately starts the other way), I suggest to set the 'Stop' trigger a little 'behind' the 'Go' trigger starting the other direction.

As LapTimer does not allow setting a trigger on top of another (to work around error situations), set it somewhere else and move it around in the Map View afterwards.

Hope that helps :-)

- Harry

Re: Sprint/Rally Question - using GPS on multiple 'tracks'

Posted: Wed Mar 14, 2012 12:33 am
by geefin
Hi Harry,

Many thanks, I like the idea of just moving the stop for each stage a little away from the other, we're really only in need of a reference in this case. How far apart do two close GPS points need to be? (to avoid the message of a point already exists in this place)

Cheers!
Graeme.

Re: Sprint/Rally Question - using GPS on multiple 'tracks'

Posted: Wed Mar 14, 2012 12:35 am
by Harry
Just create it a few hundred meters away from the first point (it is convenient to do this using the Map View instead of walking around).

- Harry