Home PageFacebookRSS News Feed
PocketGPS
Web
SatNav,GPS,Navigation
Pocket GPS World - SatNavs | GPS | Speed Cameras: Forums

Pocket GPS World :: View topic - Trail Resolution
 Forum FAQForum FAQ   SearchSearch   UsergroupsUsergroups   ProfileProfile   Log in for private messagesLog in for private messages   Log inLog in 

Trail Resolution

 
Post new topic   Reply to topic    Pocket GPS World Forum Index -> Satmap Active 10
View previous topic :: View next topic  
Author Message
Golgotha
Occasional Visitor


Joined: Dec 31, 2008
Posts: 9

PostPosted: Wed Jan 14, 2009 1:37 pm    Post subject: Trail Resolution Reply with quote

Hi,

My first post to the Satmap forum.

I've had my Active 10 for a week now and very nice it is too. I went out for a bike ride on Sunday. When I reviewed my trail I noticed that there seems to be largish gaps between readings that resulted in the trail not accurately following the path - effectivley cutting corners.

How often does the Active 10 record its position?
Do these readings become waypoints?

TIA,

Andrew.
Back to top
View user's profile Send private message
Westlothian
Occasional Visitor


Joined: Dec 07, 2008
Posts: 56

PostPosted: Wed Jan 14, 2009 1:59 pm    Post subject: Reply with quote

Hi Andrew,

Welcome!

Updates are every second, every four in Power Saving Mode.

Were these high speed sections and corners?

I could be signal loss causing jumps but I find the reception to be flawless when outdoors (so far).

Alistair
Back to top
View user's profile Send private message
Golgotha
Occasional Visitor


Joined: Dec 31, 2008
Posts: 9

PostPosted: Wed Jan 14, 2009 2:29 pm    Post subject: Reply with quote

Hi,

Thanks for the reply.

My top speed on the day was about 20mph, which works out at about 8 meters per second. So that would account for the corner cutting in the trail. I noticed that the update was a second from the waypoint list, but just wanted to confirm.

I wonder if it is possible to increase the update rate or is it limit by the hardware? 4 times per second would be nice, but I reckon battery life would decrease proportionally.

Andrew.
Back to top
View user's profile Send private message
Physicist
Occasional Visitor


Joined: Nov 08, 2007
Posts: 57
Location: Cambridge

PostPosted: Wed Jan 14, 2009 10:25 pm    Post subject: Reply with quote

US Dept of Defense only allow updating of coordinates once per second on the civilian GPS system (otherwise sets could be used to guide missiles). The military version has higher update rates.
Back to top
View user's profile Send private message
ed_crouch
Occasional Visitor


Joined: Jan 05, 2009
Posts: 6

PostPosted: Wed Jan 14, 2009 11:30 pm    Post subject: Reply with quote

'S interesting... I guess you'd have to use INS to interpolate positions between GPS fixes...
Back to top
View user's profile Send private message
jonesbach
Regular Visitor


Joined: Jun 07, 2008
Posts: 185

PostPosted: Sat Jan 24, 2009 8:14 pm    Post subject: Reply with quote

Westlothian wrote:

.....Updates are every second, every four in Power Saving Mode......


I was of the same opinion until today. In the search to stretch my battery further I tried 'power saving mode'. On inspection of raw internal gpx file(prior to it being 'condensed' for export) I find that points are still stored at anything between 1 and 3 second intervals.

When I read the manual with my eyes open Embarassed it says that the SCREEN is updated every four seconds. Does anyone know of any reference where it says that points can be logged at four second intervals. I'm using these internal files as they contain data not in the exported file and I am having to delete points to make the files manageable. It would save me work if I could force points to be saved every four seconds.
Back to top
View user's profile Send private message
mikealder
Pocket GPS Moderator
Pocket GPS Moderator


Joined: Jan 14, 2005
Posts: 19638
Location: Blackpool , Lancs

PostPosted: Sat Jan 24, 2009 8:39 pm    Post subject: Reply with quote

Go to Settings/ Advanced Power Control and use the cursor control to toggle between Advanced (which gives you a 4 second update) or Normal where you get an update once per second, the Normal selection also allows you to select the trail up map display rather than being stuck with North up all the time - Mike
Back to top
View user's profile Send private message Send e-mail MSN Messenger
jonesbach
Regular Visitor


Joined: Jun 07, 2008
Posts: 185

PostPosted: Sat Jan 24, 2009 8:52 pm    Post subject: Reply with quote

mikealder wrote:
Go to Settings/ Advanced Power Control and use the cursor control to toggle between Advanced (which gives you a 4 second update) or Normal where you get an update once per second, the Normal selection also allows you to select the trail up map display rather than being stuck with North up all the time - Mike

Mike, sorry if I've been unclear. That's what I have been doing, but I have found that track points are logged at about the same rate, i.e. anything between 1 and 3 seconds and certainly not 4 seconds. Is there any other setting required?
Back to top
View user's profile Send private message
mikealder
Pocket GPS Moderator
Pocket GPS Moderator


Joined: Jan 14, 2005
Posts: 19638
Location: Blackpool , Lancs

PostPosted: Sat Jan 24, 2009 8:59 pm    Post subject: Reply with quote

I will have to have a look at what the device is doing by taking it for a walk, are you refering to the trail points it records on screen or when you are viewing the actual recorded data on the PC? - Mike
Back to top
View user's profile Send private message Send e-mail MSN Messenger
jonesbach
Regular Visitor


Joined: Jun 07, 2008
Posts: 185

PostPosted: Sat Jan 24, 2009 9:26 pm    Post subject: Reply with quote

I'm viewing the actual recorded data on the PC. I'm copying the raw file out and reading the data by opening the xml file in the web browser. This is prior to the size reduction that occurs when the file is exported.

When set to 1 second update the files always displayed a 'band' in the sample rate(1-3) and were never consistently at 1 second intervals but I assumed this was due to processing constraints. I always assumed that there was a 4 second sample rate but never tested it.

I have now created files at both 1 second and 4 seconds sample rates and find that within reason the actual sample rate is the same.

Incidentally, I do get the impression that since v1.3 the number of samples that actually hit 1 second have increased though this could be due to wishful thinking.
Back to top
View user's profile Send private message
CheeseMeister
Occasional Visitor


Joined: Jun 02, 2005
Posts: 8

PostPosted: Sat Jan 24, 2009 10:46 pm    Post subject: Reply with quote

Does the 4 sec rate not refer to the screen update rate? I don't really see a great power saving in slowing down the rate data is obtained from the GPS rx, it should be possible to achieve 1 update/sec even with the processor clock scaled right back.


Kev.
Back to top
View user's profile Send private message
jonesbach
Regular Visitor


Joined: Jun 07, 2008
Posts: 185

PostPosted: Sun Jan 25, 2009 12:30 am    Post subject: Reply with quote

CheeseMeister wrote:
Does the 4 sec rate not refer to the screen update rate? ....

Exactly CheeseMeister! If someone can find me a 4 second log update I will be well pleased but I don't think there is one.
Back to top
View user's profile Send private message







Posted: Today    Post subject: Pocket GPS Advertising

Back to top
Display posts from previous:   
Post new topic   Reply to topic    Pocket GPS World Forum Index -> Satmap Active 10 All times are GMT + 1 Hour
Page 1 of 1

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

Make a Donation



CamerAlert Database

Click here for the PocketGPSWorld.com Speed Camera Database

Download Speed Camera Database
21.035 (29 Mar 23)



WORLDWIDE SPEED CAMERA SPOTTERS WANTED!

Click here to submit camera positions to the PocketGPSWorld.com Speed Camera Database


12mth Subscriber memberships awarded every week for verified new camera reports!

Submit Speed Camera Locations Now


CamerAlert Apps



iOS QR Code






Android QR Code







Terms & Privacy


GPS Shopping