Building Custom GPS Trackers From Scratch 📍🗺️🧭🌍🛰️

TJ VanToll

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“In the twentieth century the Wisconsin legislature rejected a petition asking the U.P. to secede from Michigan and join Wisconsin.”

Source: https://www.wxpr.org/history/2020-10-07/the-michigan-wisconsin-border-dispute-through-history

“Rabble rousers in the U.P. then petitioned to break away and form a new state with the Wisconsin Northwoods called Superior.”

Source: https://www.wxpr.org/history/2020-10-07/the-michigan-wisconsin-border-dispute-through-history

</end-fact>

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📡 GPS 📡

Agenda

• How do trackers work?
• How GPS works.
• How GPS receivers work.

​

• Building your own tracker
• Part 1: Configuration only
• Part 2: Code!

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Agenda

• How do trackers work?
• How GPS works.
• How GPS receivers work.

​

• Building your own tracker
• Part 1: Configuration only
• Part 2: Code!

17

Source: https://history.nasa.gov/sputnik/gallerysput.html

Source: http://sjhrc.org/beeps.html

Source: https://nssdc.gsfc.nasa.gov/nmc/spacecraft/display.action?id=1960-003B

Source: https://www.bbvaopenmind.com/en/technology/visionaries/the-birth-of-gps-an-unexpected-child-of-the-space-race/

Source: https://un-spider.org/news-and-events/news/55-years-satellite-navigation

Source: https://en.wikipedia.org/wiki/Atomic_clock#/media/File:Atomic_Clock-Louis_Essen.jpg

Source: https://www.omnia.ie/index.php?navigation_function=3&europeana_query=Magellan+Systems+Corporation

1983

2000

Source: https://www.schriever.spaceforce.mil/News/Article-Display/Article/2693724/2nd-sops-accepts-new-gps-satellite/

GNSS (Global Navigation Satellite System)

• GPS (US)

​

• GLONASS (Russia)

​

• BeiDou (China)

​

• Galileo (EU)

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Agenda

• How do trackers work?
• How GPS works.
• How GPS receivers work.

​

• Building your own tracker
• Part 1: Configuration only
• Part 2: Code!

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<fun-aside>

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“The heat from the friction of the air burns up the satellite as it falls toward Earth at thousands of miles per hour. Ta-da! No more satellite.”

“Spacecraft operators can plan for the final destination of their old satellites to make sure that any debris falls into a remote area. This place even has a nickname—the Spacecraft Cemetery!”

“What about those higher satellites we blast farther away? Those we send into a “graveyard orbit.”

</fun-aside>

37

Agenda

• How do trackers work?
• How GPS works.
• How GPS receivers work.

​

• Building your own tracker
• Part 1: Configuration only
• Part 2: Code!

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Source: https://spaceplace.nasa.gov/gps/en/

Source: https://www.gps.gov/multimedia/images/GPS-control-segment-map.pdf

Source: https://spaceplace.nasa.gov/gps/en/

A GPS signal contains…

• An identifier—so you know which satellite you’re getting data from.

​

• Ephemeris data—to determine a satellite’s position, as well the the current data / time.

​

• Almanac data—tells the GPS receiver where each GPS satellite should be.

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GPS Signals are affected by…

• Ionosphere and troposphere delays.

​

• Tall building and large rock structures.

​

• Walls

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Agenda

• How do trackers work?
• How GPS works.
• How GPS receivers work.

​

• Building your own tracker
• Part 1: Configuration only
• Part 2: Code!

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Why build your own tracker?

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Why build your own tracker?

• Money

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Why build your own tracker?

• Money

​

• Customizability

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AirTag limitations

• Only work on Apple devices

​

• No ability to view data outside of Apple devices

​

• No ability to set up custom notifications or alerts

​

• No ability to geofence

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Why build your own tracker?

• Money

​

• Customizability

​

• Fun! 🥳

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How to build your own tracker?

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Two problems

• How to get satellite / location data?

​

• How to send that data somewhere?

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Source: https://www.sparkfun.com/GPS_Guide

Internet of Things

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Ray Ozzie – CEO of Blues Wireless

Complexity kills. It sucks the life out of developers, it makes products difficult to plan, build, and test.

“

🔒 Securing your data from device to cloud

🔋 Building zero-config low-power hardware

👩‍💻 Providing an unmatched developer experience

​

Easy for developers and affordable for all.

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Notecard

• Global cellular/GPS or Wi-Fi
• 500MB cell data + 10 years service
• JSON-based API
• Python, Go, Arduino, C/C++

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Notecarrier

• Dev boards for easy prototyping
• Notecarrier for every scenario

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Notehub

• Route data to any cloud app
• Fleet & firmware management
• Secure communications

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Agenda

• How do trackers work?
• How GPS works.
• How GPS receivers work.

​

• Building your own tracker
• Part 1: Configuration only
• Part 2: Code!

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{

"req": "hub.set",

"product": "com.company.name:project"

"mode": "periodic",

"outbound": 3

}

{

"req": "card.location.mode",

"mode": "periodic",

"seconds": 60

}

{

"req": "card.location.track",

"start": true,

"heartbeat": true,

"hours": 12

}

Agenda

• How do trackers work?
• How GPS works.
• How GPS receivers work.

​

• Building your own tracker
• Part 1: Configuration only
• Part 2: Code!

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Swan

• Feather-compatible dev board
• Plenty of flash and RAM
• Support for C/C++, Arduino, and CircuitPython

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Demo! 🎸

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😬

Agenda

• How do trackers work?
• How GPS works.
• How GPS receivers work.

​

• Building your own tracker
• Part 1: Configuration only
• Part 2: Code!

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Thanks!

• dev.blues.io for Blues Wireless resources
• 20% off Starter Kits @ http://bit.ly/that-blues
• discuss.blues.io to join the community

TJ VanToll

@TJVanToll

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