Differences

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--- en:help:1.4:tracker [2013/10/23 12:55] – [Leaving followed path warning] alpinequest
+++ en:help:1.4:tracker [2015/09/02 11:51] – [Common issues with the Location Tracker] alpinequest
@@ Line 1: / Line 1: @@
 <sub>[[en:help|Online Help]] > [[en:help:1.4|AlpineQuest 1.4]]</sub>
+====== The Location Tracker ======
-===== The Location Tracker =====
 The AlpineQuest GPS Location Tracker is a background service that records all your locations and creates a track of your hikes.
@@ Line 9: / Line 8: @@
 Tracks can be saved within AlpineQuest or exported as GPX and KML files, that can be displayed in various softwares such as Google Earth.
-{{ :en:help:1.3:tracker_window.jpg?nolink}}
+{{ :en:help:1.4:tracker:tracker-window.jpg?nolink}}
 To start the Location Tracker, click on the toggle {{:icon_01.png?nolink}} to use the current settings. If you want to change some settings, click on the button {{:icon_02.png?nolink}} to display the Location Tracker settings dialog.
@@ Line 33: / Line 32: @@
 {{ :en:help:1.4:tracker:tracker-settings-1.jpg?nolink}}
-The two first settings are linked to the GPS Localization settings, if you change one on a side, it will be updated in the other. This behavior is done to keep a synchronization between all locations listening within the application and so reduce the battery usage.
+The two first settings are linked to the GPS Position settings, if you change one on a side, it will be updated in the other. This behavior is done to keep a synchronization between all locations listening within the application and so reduce the battery usage.
   * The "**''Location source''**" {{:icon_01.png?nolink}} let you choose from where the locations have to be retrieved. Most people will choose "**''Outdoor GPS''**", but you can change it to "**''External locations''**" if you have an external bluetooth GPS you want to use;
-  * The "**''Update frequency''**" {{:icon_02.png?nolink}} allows you to choose how fast the locations have to be recorded. For runners, a precise tracking is recommend, whereas hikers should prefer a medium one, as a fast tracking will use more battery.
+  * The "**''Update frequency''**" {{:icon_02.png?nolink}} allows you to choose how fast the locations have to be recorded. For runners, a precise tracking is recommend, whereas hikers should prefer a medium one, since a fast tracking will use more battery.
 {{:icon_help.png?nolink}} Some location sources can be disabled from the device settings. Click on the "**''Location sources''**" {{:icon_03.png?nolink}} button to access these settings easily.
-==== Leaving followed path warning ====
+==== Locations filtering ====
-While [[en:help:1.4:landmarks:follow-path|following a path]], the Location Tracker can warn you if you are going too far away from it. Just check the option {{:icon_04.png?nolink}} to enable it. You can change the warn distance using the {{:icon_05.png?nolink}} setting.
+Location filters allow you to reduce the amount of recorded locations in order to reduce the battery usage and to increase the tracking accuracy (by reducing GPS inaccuracy errors).
-{{:icon_help.png?nolink}} This warning feature is not available if no path is currently being followed.
+{{ :en:help:1.4:tracker:tracker-settings-2.jpg?nolink}}
-When being more far than the chosen distance, the application will play various sound notifications to help you find your way without handling your device:
+{{:icon_help.png?nolink}} The "''**accuracy filter**''" will avoid recording erroneous locations while temporary loss of accuracies, while the "''**distance filter**''" will avoid recording useless similar locations while not moving.
-  * When going even more far, the application will play two (2) "''**wrong way**''" beeps;
-  * When being more far that 1.5 times the chosen distance and still going more far, the application will play three (3) "''**wrong way**''" beeps
-  * When going closer to the path, the application will play two (2) "''**right way**''" beeps.
-{{:icon_help.png?nolink}} As long as the Location Tracker is running, the application itself doesn't need to be started to receive the warns.
+When a new location is computed by the GPS based on the update frequency, the application will:
+  * Check that the location accuracy is better or equals to the "''**accuracy filter**''" setting {{:icon_05.png?nolink}};
+  * Check that the distance from the previous location is greater or equals to the "''**distance filter**''" setting {{:icon_04.png?nolink}}, or that the location accuracy is better than the previous one.
-{{ :en:help:1.4:tracker:tracker-settings-2.jpg?nolink}}
+For instance, when using an update frequency of 5 seconds, a distance filter of 3 meters and an accuracy filter of +/-256 meters, all recorded locations:
+  * Will have at least 5 seconds and 3 meters between them, unless the accuracy is increasing;
+  * Will have at least an accuracy of +/-256 meters.
-==== Lost of signal warning ====
+==== Loss of signal warnings ====
 If the GPS signal is getting poor or lost, AlpineQuest will replace the green GPS Location Tracker's icon by a red one.
@@ Line 64: / Line 64: @@
-==== Locations filtering ====
+==== Barometric elevations ====
-Once the source and frequency of the locations have been chosen, you can optionally configure filters. These filters allow you to reduce the amount of the track locations (and so the battery usage) and to increase the tracking accuracy. You may need to click on "**''More settings''**" {{:icon_04.png?nolink}} to display them all.
+If your device has a built-in pressure sensor, you can activate the "**''barometric elevations''**" {{:icon_07.png?nolink}} feature which will compute elevation values based on the air pressure, in addition to the common GPS elevations. These barometric altitudes are much more accurate and reactive, and can be computed precisely even if the GPS signal is very poor.
-The "**''distance filter''**" {{:icon_07.png?nolink}} allows you to ignore locations if you haven't moved a minimum distance, whereas the "**''accuracy filter''**" {{:icon_08.png?nolink}} allows you to ignore inaccurate locations.
+{{:icon_help.png?nolink}} The barometric data is auto-calibrated by AlpineQuest using GPS locations.
-==== Barometric elevations ====
+===== Common issues with the Location Tracker =====
-If your device has a built-in pressure sensor, you can activate the "**''barometric elevations''**" {{:icon_08.png?nolink}} feature which will compute elevation values based on the air pressure, in addition to the common GPS elevations. These barometric altitudes are much more accurate and reactive, and can be computed precisely even if the GPS signal is very poor.
+A common issue when recording a track is to lost the GPS location, leading to a missing part in the track (seen as a straight line longer than usual). Usually, it happens because the device doesn't have a good enough access to the sky, for example when the device is placed in a pocket or in a bag. The GPS signal emitted by GPS satellites is weak and gets easily lost when going through any material. If you have the "**''lost of signal warn''**" {{:icon_06.png?nolink}} setting activated, the application will play a song when it looses the GPS signal.
-{{:icon_help.png?nolink}} The barometric data is auto-calibrated by AlpineQuest using GPS locations.
+Also, tracking a path requires frequent GPS location updates and some devices (mainly old or low-cost ones, but not always) doesn't support the GPS being turned on for long hours. Common symptoms in this case can be:
+  * The device becomes more hot than usual;
+  * The GPS doesn't report anymore satellites for some time, the location fix is lost, leading to a missing track part;
+  * The Location Tracker is simply closed by the system, the tracking is stopped.
+If you encounter one of these symptoms, you can try to:
+  * Reduce the tracking frequency, a location per 10 seconds is a recommended setting for hours long tracks;
+  * Use an economy tracking frequency (starting at 1 location / 20 seconds), in which the GPS is completely turned off between update. Be sure to leave your device in view of the sky so the GPS can quickly retrieve a location for each update;
+  * Turn off the recording of barometric elevations to leave the pressure sensor turned off (this one can also be the source of issues when continuously used for long time).
+===== Exporting recorded tracks =====
+  * [[en:help:1.4:landmarks:format-gpx#how_to_export_tracks_in_gpx_format|How to export tracks in GPX format ?]]
+  * [[en:help:1.4:landmarks:format-kml|How to export tracks in KML format ?]]