Heating A Home With Sunlight… And Water

April 22, 2021 by Bryan Cockfield 64 Comments

The sun is a tremendous source of energy, and while photovoltaic panels are an easy way to harvest some of that energy especially now that prices for them are incredibly low, there are plenty of other ways to tap into that free energy as well. [Engelbert] was looking for alternative ways to heat his house since traditional methods were prohibitively expensive, and ended up building a heat exchanger using solar-heated water to cover his home heating needs. (Google Translate from Dutch)

The system uses several large roof-mounted hot water heating panels. The heat captured by them is then pumped into an underground pipe network which is able to warm up a large area of earth in the summer. In the winter, that heat is able to be extracted back out of the earth and used to heat his home. The system includes almost three kilometers of pipe which are buried two meters below grade, so this will probably not be a weekend project, but it still cost much less than the €80,000 to install gas heating in his home.

[Engelbert] is able to use this self-built system to keep his home and another smaller building at a constant 23°C all year. He actually overbuilt the system slightly and has since disconnected almost half of the pipes, but we certainly understand the desire to over-engineer things around here. The only problem he has had is with various government entities that are slow to adopt energy-efficient systems like these. Perhaps the Dutch government can take some notes from the Swiss when it comes to installing geothermal systems like these.

Thanks to [Jero] for the tip!

Homebrew Metrology The CERN Way

February 26, 2021 by Dan Maloney 18 Comments

We won’t pretend to fully grok everything going on with this open-source 8.5-digit voltmeter that [Marco Reps] built. After all, the design came from the wizards at CERN, the European Organization for Nuclear Research, home to the Large Hadron Collider and other implements of Big Science. But we will admit to finding the level of this build quality absolutely gobsmacking, and totally worth watching the video for.

As [Marco] relates, an upcoming experiment at CERN will demand a large number of precision voltmeters, the expense of which led to a homebrew design that was released on the Open Hardware Repository. “Homebrew” perhaps undersells the build a bit, though. The design calls for a consistent thermal environment for the ADC, so there’s a mezzanine level on the board with an intricately designed Peltier thermal control system, including a custom-machined heat spreader blocker. There’s also a fascinatingly complex PCB dedicated solely to provide a solid ground between the analog input connector — itself a work of electromechanical art — and the chassis ground.

The real gem of this whole build, though, is the vapor-phase reflow soldering technique [Marco] used. Rather than a more-typical infrared process, vapor-phase reflow uses a perfluropolyether (PFPE) solution with a well-defined boiling point. PCBs suspended above a bath of heated PFPE get bathed in inert vapors at a specific temperature. [Marco]’s somewhat janky setup worked almost perfectly — just a few tombstones and bridges to fix. It’s a great technique to keep in mind for that special build.

The last [Marco Reps] video we featured was a teardown of a powerful fiber laser. It’s good to see a metrology build like this one, though, and we have a feeling we’ll be going over the details for a long time.

Continue reading “Homebrew Metrology The CERN Way” →

Pinephone Gets Thermal Imaging Backpack

August 3, 2020 by Lewin Day 12 Comments

When you buy a mass-market mobile phone, you’re making the decision to trust a long list of companies with your private data. While it’s difficult for any one consumer to fully audit even a single piece of consumer technology, there have been efforts to solve this problem to a degree. The Pinephone is one such example, with a focus on openness and allowing users to have full control over the hardware. [Martijn Braam] is a proud owner of such a device, and took advantage of this attitude to add a thermal imager to the handset.

The build is not a difficult one, thanks to the expansion-friendly nature of the Pinephone hardware. The rear of the phone sports six pogo pins carrying an I2C bus as well as power. [Martin] started by modifying the back cover of the phone with contacts to interface with the pogo pins. With this done, the MLX90640 thermal imager was attached to the case with double-sided tape and wired up to the interface.

While the 32×24 output from the sensor isn’t going to help you build cutting edge heat-seeking missiles, it’s an affordable sensor with good performance for low-end thermal imaging tasks. We’ve featured teardowns of thermal imaging hardware before, too.

New Breakout Board For Grid-EYE Thermal Sensor

May 18, 2020 by Donald Papp 13 Comments

Panasonic’s Grid-EYE sensor is essentially a low-cost 8×8 thermal imager with a 60 degree field of view, and a nice breakout board makes it much easier to integrate into projects. [Pure Engineering] has created an updated version of their handy breakout board for the Grid-EYE and are currently accepting orders. The new breakout board is well under an inch square and called the GridEye2 (not to be confused with the name of the main component, the AMG8833 Grid-EYE by Panasonic.)

GridEye2 connected to CH341A dev board, allowing easy PC interface over USB.

A common way to interface with the Grid-EYE is over I2C, but to make connecting and developing on a PC more straightforward, [Pure Engineering] has made sure the new unit can plug right into their (optional) CH341A development board to provide a USB interface. Getting up and running on a Linux box is then as simple as installing the Linux drivers for the CH341A, and using sample C code to start reading thermal data from an attached GridEye2 board.

The Grid-EYE is a low-cost and capable little device that mates well with an LED matrix display, and on the more advanced side, a simple Gaussian interpolation can have a striking effect when applied to low-resolution sensors, making them appear higher resolution than they actually are.

Turn Folds Into Flowers, But Not With Origami

May 5, 2020 by Dan Maloney 13 Comments

It is said that you’re not a sysadmin if you haven’t warmed up a sandwich on server. OK, it’s not widely said; we made it up, and only said it once, coincidentally enough after heating up a sandwich on a server. But we stand by the central thesis: never let a good source of excess thermal energy go to waste.

[Joseph Marlin] is in the same camp, but it’s not lunch that he’s warming up. Instead, he’s using the heat generated by his Folding@Home rig to sprout seeds for beautiful tropical flowers. A native of South Africa Strelitzia reginae, better known as the striking blue and orange Bird of Paradise flower, prefers a temperature of at least 80° F (27° C) for the two months its seeds take to sprout. With all the extra CPU cycles on a spare laptop churning out warm air, [Joseph] rigged an incubator of sorts from a cardboard box. A 3D-printed scoop snaps over the fan output on the laptop and funnels warm air into the grow chamber. This keeps the interior temperature about 15 degrees above ambient, which should be good enough for the seeds to sprout. He says that elaborations for future versions could include an Arduino and a servo-controlled shutter to regulate the temperature, which seems like a good idea.

The Bird of Paradise is a spectacular flower, but if growing beautiful things isn’t your style, such a rig could easily sprout tomatoes or peppers or get onions off to a good start. No matter what you grow, you’ll need to basics of spinning up a Folding@Home rig, which is something we can help with, of course.

Side-Channel Attacks Hack Chat With Samy Kamkar

March 23, 2020 by Dan Maloney 3 Comments

Join us on Wednesday, March 25 at noon Pacific for the Side-Channel Attacks Hack Chat with Samy Kamkar!

In the world of computer security, the good news is that a lot of vendors are finally taking security seriously now, with the result that direct attacks are harder to pull off. The bad news is that in a lot of cases, they’re still leaving the side-door wide open. Side-channel attacks come in all sorts of flavors, but they all have something in common: they leak information about the state of a system through an unexpected vector. From monitoring the sounds that the keyboard makes as you type to watching the minute vibrations of a potato chip bag in response to a nearby conversation, side-channel attacks take advantage of these leaks to exfiltrate information.

Side-channel exploits can be the bread and butter of black hat hackers, but understanding them can be useful to those of us who are more interested in protecting systems, or perhaps to inform our reverse engineering efforts. Samy Kamkar knows quite a bit more than a thing or two about side-channel attacks, so much so that he gave a great talk at the 2019 Hackaday Superconference on just that topic. He’ll be dropping by the Hack Chat to “extend and enhance” that talk, and to answer your questions about side-channel exploits, and discuss the reverse engineering potential they offer. Join us and learn more about this fascinating world, where the complexity of systems leads to unintended consequences that could come back to bite you, or perhaps even help you.

Our Hack Chats are live community events in the Hackaday.io Hack Chat group messaging. This week we’ll be sitting down on Wednesday, March 25 at 12:00 PM Pacific time. If time zones have got you down, we have a handy time zone converter.

Click that speech bubble to the right, and you’ll be taken directly to the Hack Chat group on Hackaday.io. You don’t have to wait until Wednesday; join whenever you want and you can see what the community is talking about.

Continue reading “Side-Channel Attacks Hack Chat With Samy Kamkar” →

Put The Power Of PCR In Your Pocket With This Open-Source Thermal Cycler

January 26, 2020 by Dan Maloney 23 Comments

When the first thermal cyclers for the polymerase chain reaction came out in the 1980s, they were as expensive as a market driven by grant money could make them. Things haven’t got much better over the years, largely shutting STEM classes and biohackers out of the PCR market. That may be about to change, though, if the €99.00 PocketPCR thermal cycler takes hold.

PCR amplifies DNA in a three-step process: denaturation, which melts double-stranded DNA into single strands; annealing, which lets small pieces of primer DNA bind to either side of the region of interest; and elongation, where the enzyme DNA polymerase zips along the single strands starting at the primer to replicate the DNA. The cycle repeats and copies of the original DNA accumulate exponentially. Like any thermal cycler, [Urs Gaudenz]’s PocketPCR automates those temperature shifts, using a combination of PCB-mounted heating elements and a cooling fan. The coils rapidly heat a reaction block up to the 99°C denaturation temperature, the fan brings that down to the 68°C needed for annealing, and then the temperature ramps back up to 72°C for elongation with thermostable DNA polymerase. PID loops keep the reaction temperature precisely controlled. The whole thing is, as the name suggests, small enough to fit in a pocket, and can either be purchased in kit form or scratch-built from the build files on GitHub.

We applaud [Urs]’ efforts to get the power of PCR into the hands of citizen scientists. Quick and dirty thermal cyclers are one thing, but Pocket PCR has a great fit and finish that makes it more accessible.

Thanks to [Abe Tusk] for the tip.