Catographer

A web page that plays GPS logs recorded by some logger device:

• local webpage with js
• local log text files
• internet connection is required to pull js libs and map tiles

Demo

Demo

Screenshots

Software

Requirements

• for hosting: webserver installed, e.g. Apache or Node
• for viewing: more or less up-to-date browser, any device

Instructions for Apache (for hosting under Ubuntu Linux distro)

• clone the project
• put any log files into logs/ directory (see log file format below). The directory is autoscanned on page load.
• install Apache and link the project to its root:

~$ sudo apt install apache2
~$ sudo ln -sf <project-path> /var/www/html/somename

• browser (on any device in the network):

http://<host-ip-or-hostname>/somename

Details

GPS log file example

...
$GPRMC,,V,,,,,,,,,,N*53
$GPRMC,,V,,,,,,,,,,N*53
$GPRMC,,V,,,,,,,,,,N*53
$GPRMC,,V,,,,,,,,,,N*53
$GPRMC,164322.00,A,4430.47468,N,00152.18748,E,0.085,,241119,,,
$GPRMC,164353.00,A,4430.47285,N,00152.18733,E,0.205,,241119,,,
$GPRMC,164424.00,A,4430.47163,N,00152.18751,E,0.416,,241119,,,
...

Notes:

• Each single line is a single GPS sentence (GPS logger was setup to log it in that way)
• when GPS receiver is not 'locked' the data can be empty like the first 4 lines
• only RMC sentences are used, others (like GGA) are ignored - better to filter those out

Hardware: GPS Logger

Any COTS or DIY device of a decent weight/size with internal storage available.

COTS

DIY

BOM:

• ESP8266 D1 mini (comes with 4MB flash)
• Battery shield for D1 mini (not drawing power directly from the battery)
• Small GPS receiver (serial interface required, i.e. TX/RX wires)
• Battery, rated 3.3V, 290mAh

Notes:

• Some soldering is required:
  • VCC/GND wires
  • disconnectable battery
  • GPS TX to ESP GPIO
  • ESP Deep Sleep enabling
• The GPS Logger came out light but a bit too bulky. Went ahead with testing anyways - the asset didn't lose it.
• Power saving - deep sleep for ESP, while GPS is always on - 3 hours of work with a ~30s interval between the records.

Room for improvement:

• Can easily be made smaller (~2x times) in dimensions: move away from D1 mini and the battery shield.
• Implement GPS power saving programmaticaly (if GPS module supports it) or by ESP's GPIO.