Open Source Tricorder Is In It For The Science

September 30, 2026 by Tyler August 11 Comments

If you’re reading Hackaday there’s pretty good odds you’re at least somewhat fond of Star Trek. We’d bet good money most of you would quit your jobs today if a Starfleet recruiter showed up. That’s something you’d have in common with [PeterAJansen], who has been working for over a decade now to create something worthy of being called a tricorder. If his latest iteration, the Open Source Science Tricorder Cyberdeck, isn’t there yet, it’s pretty darn close.

Frankly, it looks more usable than Roddenberry’s version.

The “tri” in tricorder means three, but this device has more than three instruments– so did the ones on the show, come to think of it. You won’t be scanning for veteron radiation with this, but you do get a scintillation crystal to get a spectroscopic analysis of beta- or gamma-ray sources; there’s also a visible light spectrometer, thermal camera, and magnetic field camera along with a standard magnetometer and the usual environmental sensors to give you temperature, pressure, and humidity, plus particulate, VOC and CO2 concentration. Enough to explore an alien planet? That’s hard to say, but it seems like enough to explore this one.

The device is based around a Clockwork Pi uConsole, which takes care of the form-factor: a slabtop with a QWERTY keyboard and an IPS display in a nice screen, and a Compute Module 5 to crunch all that data. It might not be quite as stylish as the folding units seen on-screen in Star Trek, but it seems like an eminently practical form factor. There are videos of it in operation as well as being assembled on the GitHub repository, where you can get all the details needed to make your own. It is the Open Source Science Tricorder, after all.

This isn’t the first project we’ve seen chasing tricorder glory, but many of the others were more interested in screen accuracy than science. [Peter]’s earlier “arducorder” was a very notable exception to that trend.

Thanks to [MarcCote] for the tip! If your scanners pick up something interesting in cyberspace, remember our hailing frequencies are always open.

Ways To Empirically Identify A Magnet’s Polarity

September 27, 2026 by Donald Papp 13 Comments

Every magnet has a north and a south pole, but which is which? Sometimes it matters. If a product one builds features a magnetic closure or other part, the polarity of those magnets should be consistent in assembly. So how does one ensure they never glue a magnet wrong again? [Clough42] shows several ways to identify a magnet’s north and south poles using things many of us probably have ready at hand, and goes into a bit of theory while he’s at it.

Probably the easiest way is to use a known-good and clearly labeled reference magnet. Same poles repel, and opposites attract. But if that’s not available, a simple magnetic compass can help. Because opposite poles attract, a compass’s north point will be attracted toward a magnet’s south pole, and vice versa.

A Hall effect sensor, or an electromagnet — the winding and current flow determine the polarity — are other ways to measure a magnet’s poles. And here’s where [Clough42] dives into some details of how magnetic fields actually act, because it explains some seemingly strange behavior.

For example, at around 4:08 he demonstrates a Hall effect sensor board that is documented as lighting an LED when the south pole of a magnet is held to its front. It does that, but it also lights the LED when the north end of the magnet is held to the sensor’s back. That’s because the sensor isn’t actually directly sensing the magnet’s pole, it’s sensing the orientation of a magnetic field. The lesson is clear: make sure you’re measuring what you think you’re measuring. Near the end of the video he demonstrates a similar experience with a handy mobile phone app that senses magnetic fields by reading the device’s internal magnetic compass; by waving a strong magnet around, the detected polarity flips back and forth even though the magnet’s orientation isn’t changed.

So what does one do after positively identifying a magnet’s north and south poles? Label it clearly for use as a known-good reference magnet in the future is our suggestion. Watch the whole video below, then take a few minutes to dive into the nitty-gritty of what magnets actually are and how they work.

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Hackaday Europe 2026: Open Source Hardware Goes Underground, Literally

August 17, 2026 by Tom Nardi 7 Comments

These days open source is everywhere, and frankly, we couldn’t be happier about it. But even with as prevalent as open software and hardware has become, we still occasionally hear about a project that takes the concept somewhere unexpected. Which is precisely why we were so eager to hear more about the fascinating work [Phil Underwood] has been doing.

In his talk Open Source Caving: 20 Years of Making Cave Mapping Tools at Hackaday Europe 2026, [Phil] takes us through a series of progressively more advanced open hardware devices that he’s designed to increase the speed and accuracy of underground mapping efforts. Along the way, he’s learned a number of valuable lessons about designing hardware that’s robust enough to handle the uniquely challenging environment underground while still being accessible enough for a hobbyist to build and use.

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MagQuest: Measuring Earth’s Magnetic Field With Space-Based Quantum Sensors

December 9, 2025 by Maya Posch 8 Comments

Recently the MagQuest competition on improving the measuring of the Earth’s magnetic field announced that the contestants in the final phase have now moved on to launching their satellites within the near future. The goal here is to create a much improved World Magnetic Model (WMM), which is used by the World Geodetic System (WGS). The WGS is an integral part of cartography, geodesy and satellite-based navigation, which includes every sat nav, smartphone and similar with built-in GNSS capabilities.

Although in this age of sat navs and similar it can seem quaint to see anyone bother with using the Earth’s magnetic field with a compass, there is a very good reason why e.g. your Android smartphone has an API for estimating the Earth’s magnetic field at the current location. After your sat nav or smartphone uses its magnetometer, the measurements are then corrected so that ‘north’ really is ‘north’. Since this uses the WMM, it’s pertinent that this model is kept as up to date as possible, with serious shifts in 2019 necessitating an early update outside of the usual five-year cycle.

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Simple Stack Of Ferrites Shows How Fluxgate Magnetometers Work

November 20, 2024 by Dan Maloney 8 Comments

Have you ever wondered how a magnetometer works? We sure have, which was why we were happy to stumble upon this article on simple homebrew fluxgate magnetometers.

As [Maurycy] explains, clues to how a fluxgate magnetometer works can be found right in the name. We all know what happens when a current is applied to a coil of wire wrapped around an iron or ferrite core — it makes an electromagnet. Wrap another coil around the same core, and you’ve got a simple transformer.

Now, power the first coil, called the drive coil, with alternating current and measure the induced current on the second, or sense coil. Unexpected differences between the current in the drive coil and the sense coil are due to any external magnetic field. The difference indicates the strength of the field. Genius!

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The Apple Watch As An Ammeter

September 10, 2024 by Jenny List 3 Comments

Your shiny new personal electronic device is likely to be designed solely as an app platform to run the products of faceless corporations, so the story goes, and therefore has an ever smaller hacking potential. Perhaps that view is needlessly pessimistic, because here’s [JP3141] with an example that goes against the grain. It’s an Apple Watch, being used as an ammeter. How it does that comes as the result of a delicious piece of lateral thinking.

Like many mobile devices, the device comes with a magnetometer. This serves as an electronic compass, but it’s also as its name might suggest, an instrument for sensing magnetic fields in three axes. With a 3D printed bobbin that slides over the watch, and a few turns of wire, it can sense the magnetic field created by the current, and a measurement can be derived from it. The software on the watch is only a simple proof of concept as yet, but it applies some fairly understandable high-school physics to provide a useful if unexpected measure of current.

We’re surprised to see just how many times the Apple Watch has appeared on these pages, but scanning past projects it was a cosmetic one which caught our eye. Who wouldn’t want a tiny Mac Classic!

Quantum Sensor Uses Synthetic Diamond

August 18, 2024 by Al Williams 3 Comments

Diamonds are nearly perfect crystals, but not totally perfect. The defects in these crystals give the stones their characteristic colors. But one type of defect, the NV — nitrogen-vacancy — center, can hold a particular spin, and you can change that spin with the correct application of energy. [Asianometry] explains why this is important in the video below.

Interestingly, even at room temperature, an NV center stays stable for a long time. Even more importantly, you can measure the spin nondestructively by detecting light emissions from the center.

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