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Spooky Wi-Fi geolocation node for ROS2. Acts like a GPS when you don't have one

Hi everyone,
I made a spooky ROS2 node that geolocates a device and publishes a NavSatFix when you don’t have a hardware GPS. It requires either “nmcli” or “iwlist” to be installed to do a Wi-Fi scan, can use either the free Mozilla API or paid Google API, and could also potentially be used as a fallback for when you are under a structure and GPS doesn’t work.

Please use free APIs responsibly; it is not intended for high frequency updates.

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Very cool Dheera! Does the module also allow learning new, custom wifi maps and using them to locate inside buildings? That could be very useful in many applications, especially multi-floor applications.

This does not allow learning new wifi maps, it just uses the Mozilla/Google API, although Mozilla/Google do learn about new Wi-Fi access points over time, especially Google if you walk around with an mobile phone that sends back GPS+Wi-Fi data automatically.

As for a custom Wi-Fi map, that’s definitely a cool idea, I’ve actually done that many years ago at MIT in dorms that have a ton of access points, and the nice thing about that is that it can work entirely offline as long as the robot has Wi-Fi hardware. I’ll think about re-doing that at some point since that was before ROS and neural net frameworks were popular, which could simplify the implementation a lot.

One idea I have is to take an input ground truth /odom topic, have an output /odom_estimate topic, and then if /odom is publishing, pass it through to /odom_estimate while also continually training a very simple and lightweight network in PyTorch to spit out a location given the /odom and a Wi-Fi scan. If the /odom topic stops publishing, then just evaluate the network on the Wi-Fi scan and publish the /odom_estimate.

On a side note some people at MIT and CMU did centimeter-level localization with Wi-Fi and some kernel/driver hacking to extract time-of-flight information of the Wi-Fi signal: https://www.usenix.org/system/files/conference/nsdi16/nsdi16-paper-vasisht.pdf

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