The name Gladys West is probably unfamiliar, but she was part of creating something you probably use often enough: GPS. You wouldn’t think a child who grew up on a sharecropping farm would wind up as an influential mathematician, but perhaps watching her father work very hard for very little and her mother working for a tobacco company made her realize that she wanted more for herself. Early on, she decided that education was the way out. She made it all the way to the Naval Surface Warfare Center.
While she was there she changed the world with — no kidding — mathematics. While she didn’t single-handedly invent satellite navigation, her work was critical to the systems we take for granted today.
It’s built around the Arduino MKR GSM, a special Arduino built specifically for Internet of Things project. Sporting a cellular modem onboard, it can communicate with GSM and 3G networks out of the box. It’s paired with the MKR GPS shield to determine the bike’s location, and a ADXL345 3-axis accelerometer to detect movement. When unauthorised movement is detected, the tracker can send out text messages via cellular connection in order to help the owner track down the missing bike.
The tracker goes for a stealth installation, giving up the deterrent factor in order to lessen the chance of a thief damaging or disabling the hardware. It’s a project that should give [Johan] some peace of mind, though of course knowing where the bike is, and getting it back, are two different things entirely. We’ve seen creative techniques to build trackers for cats, too. It used to be the case that such “tracking devices” were the preserve of movies alone, but no longer. If you’ve got your own build, be sure to let us know on the tipline!
In Pirates of the Caribbean, Captain Jack Sparrow has an enchanted compass that points to what the holder wants most in life. The Pizza Compass created by [Joe Grand] is basically the same thing, except it’s powered by a Particle Boron instead of a voodoo spell. Though depending on who’s holding the thing, we imagine they’d even point in the same direction.
[Joe] was tasked by Wired to design and produce the Pizza Compass in three weeks, a process which was documented in the video below. Being the Badgelife luminary that he is, the final product looks far more attractive than it has any business being. In addition to the Particle Boron that slots in on the back of the handheld PCB, there’s a GlobalTop PA6H GPS module, a LSM303DLHC compass, and eight NeoPixels that correspond to the points on the silkscreen compass.
Using the device is simple, just press the button and then walk around trying to keep the top-most LED lit. Behind the scenes, the Boron is pulling down the coordinates of the closest pizza place as reported by Google’s API, and comparing that to the user’s current GPS location. In practice that means the Pizza Compass isn’t concerned with nuances like streets or buildings, so its up to the user to figure out how best to stay on the desired heading. So rather than just following some turn-by-turn directions, there’s some proper navigation involved if you want that fresh slice.
If you don’t like pizza, you could reprogram the compass to point to whatever quest-worthy resource you wish. As explained at the end of the video, [Joe] wanted this to be an open source project so it could easily be adapted for different tasks by the community. Though honestly, it’s pretty weird if you don’t like pizza.
[Dave Akerman]’s ongoing high altitude balloon (HAB) work is outstanding, and we’re all enriched by the fact that he documents his work like he does. Recently, [Dave] wrote about his balloon tracker based on the Raspberry Pi Pico, whose capabilities brought a couple interesting features to the table.
In a way, HAB trackers have a fairly simple job: read sensors such as GPS and constantly relay that data to someone on the ground so that the balloon’s location can be tracked, and the hardware recovered when it ultimately returns to Earth. There are a lot of different ways to do this tracking, and one thing [Dave] enjoys is getting his hands on a new board and making a HAB tracker out of it. That’s exactly what he has done with the Raspberry Pi Pico.
Nothing builds familiarity like actually using a part, and the Pico had some useful things to contribute to a HAB tracker application. For one thing, the Pico has an onboard buck-boost converter that allows it to be powered from a relatively wide voltage range (~1.8 V to 5.5 V), so running it directly from batteries is both possible and desirable from a tracker perspective. But a really useful feature was possible thanks to the large amount of memory on the Pico: dynamic landing prediction.
[Dave] does landing prediction prior to launch based on environmental conditions, but it’s always better if the HAB tracker can also calculate its own prediction based on actual observed events and conditions. A typical microcontroller board like an Arduino doesn’t have enough memory to store the required data upon which to do such calculations, but the Pico does so easily. [Dave]’s new board transmits an updated landing site prediction along with all the rest of the telemetry, making the retrieval process much more reliable.
GPS technology is a marvel of the modern world. Not only can we reliably locate positions on the planet with remarkable accuracy and relatively inexpensive hardware, but plenty of non-location-based features of the technology are available for other uses as well. GPS can be used for things like time servers, since the satellites require precise timing in order to triangulate a position, and as a result they can also be used for things like this incredibly accurate frequency reference.
This project is what’s known as a GPSDO, or GPS-disciplined oscillator. Typically they use a normal oscillator, like a crystal, and improve its accuracy by pairing it with the timing signal from a GPS satellite. This one is a standalone model built by [Szabolcs Szigeti] who based the build around an STM32 board. The goal of the project was purely educational, as GPSDOs of various types are widely available, but [Szabolcs] was able to build exactly what he wanted into this one including a custom power supply, simple standalone UI, and no distribution amplifier.
The build goes into a good bit of detail on the design and operation of the device, and all of the PCB schematics and source code are available on the projects GitHub page if you want to build your own. There are plenty of other projects out there that make use of GPS-based time for its high accuracy, too, like this one which ties a GPS time standard directly to a Raspberry Pi.
Randonauting is the pastime of using random numbers to generate a destination to visit, in the pursuit of adventure. Of course, anything that can be done on a website with a script is even cooler with custom hardware, so [Decker] built a rig for the job.
The device uses a USB hardware random number generator to produce truly random numbers through quantum effects; at least, according to our best theories of the universe. These numbers are then used to pick a random set of GPS coordinates and a time in which to be there, a fun twist on traditional Randonauting of [Decker]’s own creation.
At its heart, it’s a random number generator pumped through some Python scripts. Where this build elevates itself is not in the mechanics, but the presentation. The rig runs on a Raspberry Pi, inside a bell jar, with a vacuum fluorsecent display, fairy lights and plumbing components. It plays on the cyberpunk aesthetic, and it’s so much harder to ignore one’s mission when the time and place are given in glowing numerals by an enigmatic, mysterious machine.
These days, there’s plenty of options if you want to get a GPS tracker for your vehicle. Unfortunately, they come with the sort of baggage that’s becoming increasingly common with consumer tech: subscription fees, third-party snooping, and a sneaking suspicion that you’re more commodity than customer. So [Viktor Takacs] decided to take things into his own hands and create an open GPS tracker designed for privacy minded hackers.
As [Viktor] didn’t want to reinvent the wheel, his design leverages several off-the-shelf modules. The core of the tracker is the ESP32, which gives him plenty of computational power while still keeping energy consumption within reasonable levels. There’s also a NEO-6M GPS receiver which works at the same 3.3 V level as the ESP32, allowing the microcontroller to read the NMEA sentences without a level shifter. He decided to go with the low-cost SIM800L GSM modem, but as it only works on 2G networks, provisions have been made in the board design to swap it out for a more modern module should you desire.
For the code to glue it all together, [Viktor] pulled in nearly a dozen open source libraries to create a feature-complete firmware that uses MQTT to create a database of location data on his personal server. From there the data is plugged into Home Assistant and visualized with Grafana. This is enough to deliver core functionality, but he says that more custom software components as well as a deep-dive into the security implications of the system is coming in the near future.