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<p>Hi all,</p>
<p>I have recently been using OSRM to do map-matching for transit
vehicles, with locations from historical GPS data. The
documentation on creating profiles is pretty minimal from what I
can tell, so I've just been able to make a few modifications to
the car.lua profile to allow vehicles to go on streetcar tracks,
agency service roads, etc. <br>
</p>
<p>The data I've been playing with so far has a ~20second sampling
frequency, which has worked well, but I'm about to start working
with data that has a lower sampling rate (30-60secs) and I'm
worried that I'll get a lot of spurious matches. I was wondering
if it is possible to modify the profile such that a strong
preference is given to known transit routes (which are tagged with
route relations in OSM). Transit almost always follows a known
route, but sometimes it detours, and it's important to my research
to be able to capture that in matched GPS data. <br>
</p>
<p>What might be a good way to add this to a routing profile? Does
everything in the profile come down to speed, access, and
node-related penalties? Would I want to artificially inflate the
"speed" of transit-served streets? Is there more thorough
documentation on profiles somewhere than what is provided <a
moz-do-not-send="true"
href="https://github.com/Project-OSRM/osrm-backend/wiki/Profiles">here</a>?<br>
</p>
<p>The profile I've been using is:<br>
<a class="moz-txt-link-freetext" href="https://github.com/SAUSy-Lab/retro-gtfs/blob/master/etc/ttc.lua">https://github.com/SAUSy-Lab/retro-gtfs/blob/master/etc/ttc.lua</a></p>
<p>Any help would be greatly appreciated!<br>
</p>
<div class="moz-signature">-- <br>
Nate Wessel <br>
Jack of all trades, Master of Geography <br>
<a href="http://sausy.ca">SAUSy Lab</a>, Sid Smith Hall</div>
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