[gps-talkusers] Re: my first trip with 4.0--not good

I planned to send a replay, but my mPower locked up when I tried to play a media file and I had to reset partway through the route; I will try again tomorrow. I say routes are created from the nearest POI or route start/end because both times I created a route (I recreated the route to get back home instead of reversing) the amount of wps missed was the number of intersections between my house and my position (the first time, but I had no fix until I had passed those 2) and my friend's house and my position the second time. I can give you more exact examples when my BN and I go for a walk tomorrow (hopefully). I will save the route file and a .trc file, plus write notes as I go. 

Have a great day,
Alex


----- Original Message -----
From: Charles LaPierre <charles@xxxxxxxxxxxxxxxx
To: gps-talkusers@xxxxxxxxxxxxx,gps-talkusers@xxxxxxxxxxxxx
Date sent: Sun, 29 Jul 2007 20:12:25 -0700
Subject: [gps-talkusers] Re: my first trip with 4.0--not good



Hi Alex, let me try to explain some issues you are encountering.
See below.



At 06:27 PM 7/29/2007, Alex Parks wrote:

Hi all,



I just tried to walk a simple, half-mile route then come back.
Because of the Blue Logger I had to create the route partway
through, but as soon as I did I had "skipped 2 points along 
route".
How could I since I had created the route not five seconds 
previous

to that message?



A possible reason why this may occur.
GPS does jump around and before you created the route your GPS
position could have been quite far from where you are, and 
therefor
the starting point you already passed and then the nearest point 
may

be a non-turning waypoint and therefore the next waypoint you are
trying to get to is the next turn at Waypoint #3.



Waypoint 1 is the GPS location when you pressed create route,
Waypoint #2 is either going to be the next intersection ahead (if
your GPS location is less than 50 feet from the nearest street), 
or
Waypoint #2 is going to be the perpendicular bisection from the 
GPS

location to a point on the street which forms a 90 degree angle)
(i.e. a straight line from your GPS to the street) which will be 
a

turning point on the street and then Waypoint #3 will be the next
intersection.
So after the route is created then the system looks to see where 
your

new "current" location is along the route and will take distance
readings between yourself and WP1, WP2, WP3 etc.  and if you are
closer to WP3 then it will say skipped x number of waypoints.



Sorry if that is confusing, but behind the scene that is what is
going on, the system is constantly looking to see if you are on
route, which waypoints you are closer to and if you never reach a
specific one and you are all of a sudden closer to a waypoint 
further

down your route that is when you will get the skipped x # of
waypoints along your route.  Unless you turn on "Force sequential
route following"  Then it won't skip waypoints.




Anyway, all turns were announced very early and I kept getting
sequences of messages like "Approaching xxx street in 250 ft." 
"Turn
right on xxx street". "xxx street, 100 ft ahead". Why would it 
say I

was approaching, tell me to turn, then tell me I had not even
reached the street onto which it just told me to turn??? BTW, my
accuracy through this little treck was between 25 and 54 ft (4-7 
satellites).
Ok first it sounds like you also have Lookaround mode 
"Intersections"

turned on, this could be causing the duplicate messages about
upcoming intersections as well as the route announcements.
The system will give you 2 messages, one announcing the 
"Approaching"

turn, and then when you get closer to the turn a "Turn Now"
message. These messages are should be announced ahead of time, 
to
give you enough time to prepare yourself for the upcoming turn. 
With
GPS error and map error the last thing we want to do is for you 
to
actually hit the street, cross the street and then the system 
tells

you "oh by the way that was the street you were soposto turn on".
The BlueLogger by the way isn't as accurate as the newer Holux 
Slim
237 (Sirf III) GPS receiver which is smaller, alot more accurate, 
and

has a very fast time to first fix (I usually get a GPS fix within
about 15-20 seconds).
I love the new interface and bluetooth receiver handling. I love 
the

new POI database and other updates to the maps. The routes and
accuracy are quite bad, though. I will say they are not as bad as
they were in 3.5, but it is like routes are planned from either 
your

starting or ending point in a previous route or something and not
from where you are at the time at which you create the route. I 
must
just be lucky--I seem to always be the one with the bad 
experiences

with these updates. <smile
Alex this doesn't sound right, the system does pick your current 
GPS
location as the starting point (as long as you are in GPS mode. 
If

you are in Virtual mode it will pick your Virtual location as the
starting point.
Please send me a route in your opinion is "bad" and I will look 
to

see what the system did.  Also tell me what the route should have
done instead.  Also it may help to send me a "Replay" of your GPS
when you create the route so I can see what is going on.



Thanks.
Charles.




Have a great day,
Alex



Charles M. La Pierre CTO
Sendero Group, LLC



Lat. 37 15' 25" N  Lon: 121 53' 04" W

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