A Dutch City Gets A €600,000 Fine For WiFi Tracking

May 8, 2021 by 51 Comments

It’s not often that events in our sphere of technology hackers have ramifications for an entire country or even a continent, but there’s a piece of news from the Netherlands (Dutch language, machine translation) that has the potential to do just that.

Enschede is an unremarkable but pleasant city in the east of the country, probably best known to international Hackaday readers as the home of the UTwente webSDR and for British readers as being the first major motorway junction we pass in the Netherlands when returning home from events in Germany. Not the type of place you’d expect to rock a continent, but the news concerns the city’s municipality. They’ve been caught tracking their citizens using WiFi, and since this contravenes Dutch privacy law they’ve been fined €600,000 (about $723,000) by the Netherlands data protection authorities.

The full story of how this came to pass comes from Dave Borghuis (Dutch language, machine translation) of the TkkrLab hackerspace, who first brought the issue to the attention of the municipality in 2017. On his website he has a complete timeline (Dutch, machine translation), and in the article he delves into some of the mechanics of WiFi tracking. He’s at pains to make the point that the objective was always only to cause the WiFi tracking to end, and that the fine comes only as a result of the municipality’s continued intransigence even after being alerted multiple times to their being on the wrong side of privacy law. The city’s response (Dutch, machine translation) is a masterpiece of the PR writer’s art which boils down to their stating that they were only using it to count the density of people across the city.

The events in Enschede are already having a knock-on effect in the rest of the Netherlands as other municipalities race to ensure compliance and turn off any offending trackers, but perhaps more importantly they have the potential to reverberate throughout the entire European Union as well.

GME-Tracking Rocketship For The Diamond-Handed Traders

February 11, 2021 by 4 Comments

If you’ve been on the internet lately, you’ve been bombarded by stories about retail traders attempting to beat Wall Street at their own game by trying to force a short squeeze on GameStop stock. It’s inspired memes, songs, and all manner of political discourse, along with this cute stock-tracking device built by [dickdemodickmarcinko].

The device is based on the typical exhortation that a given stock or cryptocurrency is going “to the moon”, i.e. skyrocketing upwards to great heights. IT consists of an ESP8266 in a 3D printed housing, with a HD44780 alphanumeric LCD displaying the GME stock price and percentage change over time. The microcontroller also controls a stepper motor, which rotates a 3D-printed rocketship up or down relative to the stock’s price changes. If it’s pointing straight up, prospects are good for those holding the stock!

Whether or not the GME squeeze happens, the build is a fun way to learn about electronics and the stock market at the same time, and could be readily repurposed to track other markets in future. We’ve featured other price trackers before, like this traffic light keeping an eye on Bitcoin. Video after the break.

Tracking Satellites: The Nitty Gritty Details

December 16, 2020 by 18 Comments

If you want to listen to satellites, you have to be able to track them as they pass over the sky. When I first started tracking amateur satellites, computing the satellite’s location in the sky was a part of the challenge. Nowadays, that’s trivial. What’s left over are all the extremely important real-world details.  Let’s take a look at a typical ham satellite tracking setup and see how it all ties together.

Rotators for Steering

The popularity of robotics, 3D printing, and CNC machines has resulted in a deluge of affordable electric motors and drivers. It’s hard to imagine that an electric motor for rotating an antenna would be anything special, but in fact, antenna rotators are non-trivial engineering designs. Most of the challenges are mechanical, not electrical — the antennas that they drive can be huge, have significant wind loading and rotational inertial, and just downright weigh a lot. A rotator design has to consider bearings, weather exposure, all kinds of loads, not just rotational. And usually a brake is required to keep the antenna pointed in windy conditions.

There’s been a 70-some year history of these mechanisms from back in the 1950s when Cornell Dubilier Electronics, the company you know as a capcacitor manufacturer, began making these rotators for television antennas in the 1950s. I was a little surprised to see that the rotator systems you can buy today are not very different from the ones we used in the 1980s, other than improved electronic controls. Continue reading “Tracking Satellites: The Nitty Gritty Details” →

Roll Your Own Tracking

December 8, 2020 by 35 Comments

The smartphone is perhaps the signature device of our modern lives. For most of the population it is never more than an arm’s length away, it’s on your person more than any other device in your life. Smartphones are packed with all sorts of radios and ways to communicate wireless. [Amine Mansouri] built an ESP8266 based tracking device that takes advantage of this.

Most WiFi-enabled devices will send out “probe requests” frames trying to search for the SSIDs they were connected to. These packets contain the device MAC address as well as the SSIDs you’ve connected to. Using about 12 components, [Amine] laid out a small board in Eagle. By putting the ESP8266 in monitor mode, the probe frames can be logged and uploaded. The code can be updated OTA making it easy to service while in the field.

With permission from his local library, eight repeater boards were scattered throughout the building to forward the probe packets to where the tracker could pick them up. A simple web interface was built that allows the library to figure out how many people are in the library and how often they frequent the premises.

While an awesome project with open-source code on Github, it is important to stress how important is it to get permission to do this kind of tracking. While some phones implement MAC randomization, there are still many out in the wild that don’t. While this is similar to another project that listens to radio signals to determine the coming and going of ships and planes, tracking people with this sort of granularity is in a different category altogether.

Thanks [Amine] for sending this one in!

Tracking Drone Flight Path Via Video, Using Cameras We Can Get

November 13, 2020 by 4 Comments

Calculating three-dimensional position from two-dimensional projections are literal textbook examples in geometry, but those examples are the “assume a spherical cow” type of simplifications. Applicable only in an ideal world where the projections are made with mathematically perfect cameras at precisely known locations with infinite resolution. Making things work in the real world is a lot harder. But not only have [Jingtong Li, Jesse Murray et al.] worked through the math of tracking a drone’s 3D flight from 2D video, they’ve released their MultiViewUnsynch software on GitHub so we can all play with it.

Instead of laboratory grade optical instruments, the cameras used in these experiments are available at our local consumer electronics store. A table in their paper Reconstruction of 3D Flight Trajectories from Ad-Hoc Camera Networks (arXiv:2003.04784) listed several Huawei cell phone cameras, a few Sony digital cameras, and a GoPro 3. Video cameras don’t need to be placed in any particular arrangement, because positions are calculated from their video footage. Correlating overlapping footage from dissimilar cameras is a challenge all in itself, since these cameras record at varying framerates ranging from 25 to 59.94 frames per second. Furthermore, these cameras all have rolling shutters, which adds an extra variable as scanlines in a frame are taken at slightly different times. This is not an easy problem.

There is a lot of interest in tracking drone flights, especially those flying where they are not welcome. And not everyone have the budget for high-end equipment or the permission to emit electromagnetic signals. MultiViewUnsynch is not quite there yet, as it tracks a single target and video files were processed afterwards. The eventual goal is to evolve this capability to track multiple targets on live video, and hopefully help reduce frustrating public embarrassments.

[IROS 2020 Presentation video (duration 14:45) requires free registration, available until at least Nov. 25th 2020.]

Tracking Satellites With A Commodore PET

October 29, 2020 by 16 Comments

A recent writeup by Tom Nardi about using the 6502-based NES to track satellites brought back memories of my senior project at Georgia Tech back in the early 80s.  At our club station W4AQL, I had become interested in Amateur Radio satellites.  It was quite a thrill to hear your signal returning from space, adjusting for Doppler as it speeds overhead, keeping the antennas pointed, all while carrying on a brief conversation with other Earth stations or copying spacecraft telemetry, usually in Morse code.

Continue reading “Tracking Satellites With A Commodore PET” →

Tracking Boats And Ships In Real Time At The Same Time

October 22, 2020 by 15 Comments

Software-defined radio came on the hacker scene in a big way less than a decade ago thanks to the discovery that a small USB-based TV tuner dongle could be used for receiving all kinds of radio transmissions. Two popular projects from that era are tracking nearby airplanes and boats in real time. Of course, these projects rely on different frequencies and protocols, but if you live in a major port city like [Ian] then his project that combines both into a single user interface might be of interest.

This project uses an RTL-SDR dongle for the marine traffic portion of the project, but steps up to a FlightAware Pro dongle for receiving telemetry from airplanes. Two separate antennas are needed for this, and all of the information is gathered and handled by a pair of Raspberry Pis. The Pis communicate with various marine and air traffic databases as well as handles the custom user interface that knits both sets of information together. This interface was custom-built from a previous project of his and was repurposed slightly to fit the needs of this one.

This is a great project that goes into a lot of interesting detail about how the web traffic moves and how the UI works, so even if you’re not into software-defined radio it might be worth a look. However, it’s also worth noting that it hasn’t been easier to set up a system like this thanks to the abundance and low price of RTL-SDR dongles and the software tools that make setting them up a breeze.