wildtreetech/crumbs

Robust, simple to use GPS data loggers

CRUMBS

A robust, simple and easy to use GPS data logger. And basic software tools to use the collected data.

The first goal of the project is to create ~20 "stage 2" devices that are ready for use in April 2017.

Hardware | Firmware | Server

Use cases

Potential use cases are infinite, this is a shorter list where we know of a potential user:

• backup GPS logger for a motorbike based survey of rural areas
• data collection after a natural disaster to produce road maps
• real time fleet tracking by text message

ROADMAP

The ROADMAP has moved.

Contributing

CRUMBS is an open project, anyone is welcome to contribute. To propose changes to any of the documents or software fork this repository and make a Pull Request. Discuss ideas by creating an issue. Check the ROADMAP for things that need work or just start contributing.

Licensing

The default license is BSD-3. This is usually applied to software, so do we need to pick a hardware license that fits the BSD-3 philosophy?

crumbs's Issues

ROADMAP

Where are we headed?

Vision or very long term goal

A open-source platform that can be used for humanitarian GPS tracking and logging. hackable, low cost, and robust.

This roadmap is organized into stages of development, leading towards
a field tested design that can be extended for new needs.

Stage 1

• breadboard assembly of components
• record GPS traces in memory and SD card
  • battery powered data logging (temperature not GPS)
  • battery powered GPS logging
• simple REST end point to upload data to
• first iteration of a case to house components
• tools to overlay traces on existing maps
• define data format

Stage 2

• record GPS traces for short time (~2min) and then sleep for a
  long time (10min)
• second iteration of case
• less simple REST end point to upload data to (identify individual devices, JSON API)
• combined power supply using 12V motorbike power and a battery

Stage 3

• broadcast recorded GPS points when near a friendly WiFi AP
• server that receives GPS points, can display them and export to other
  formats

Stage 4

• add GSM module to transmit location every N minutes
• server that listens for text messages and records them

No case for the components

Need to design a case that can hold our components and protects them from the environment.

Points to consider:

• need to make about 20 units
• can't be metal (Faraday cage)
• protect components from dust and water
• need to be able to plug in an external power source
• securely attach to a motorbike
• it is ok that removing the SD card means disassembling the case -> needs to be re-openable/-closeable

Power only from battery

Is it feasible to run the whole setup only from a battery?

This would simplify the setup considerably for deployment on motorbikes. No need for external power connections, 12V -> USB convert (or is it 6V on your bike?) etc.

The ultimate GPS from Adafruit claims to use about 20-25mA (25mA tracking, 20 mA current draw during navigation). With a 2500mAh LiPo only about 100h of operation.

60 days deployment, 4 measurements per hour -> (100/60/(4*24))*60 ~ 1min per measurement. Not long enough to get a GPS lock?!?? Could save power by only waking up every 30minutes during the night.

Big batteries: 4400mAh 6600mAh

Webpage and logo

This project needs a less geeky version of some of this content.

I like

for a logo. Simple, reminds you of mapping.

https://html5up.net/story as HTML template to get started.

Questions to answer on the page:

• what is this all about, why are we doing this?
• what are we making?
• how can I get involved?

No firmware for GPS setup

Need to write some firmware that records GPS points and stores them onto a SD card.

Points to consider:

• needs to be rock solid, no crashes for months
• find an efficient and yet simple storage scheme for time, lat, long, heading, speed (not ascii!)
• put everything to sleep for minutes at a time to save battery/storage then wake up and record several points
• no need to automatically sync over wifi