Hack My House: Raspberry Pi As A Touchscreen Thermostat

Your thermostat is some of the oldest and simplest automation in your home. For years these were one-temperature setting and nothing more. Programmable thermostats brought more control; they’re alarm clocks attached to your furnace. Then Nest came along and added beautiful design and “learning features” that felt like magic compared to the old systems. But we can have a lot more fun. I’m taking my favorite single-board computer, the Raspberry Pi, and naming it keeper of heat (and cool) by building my own touchscreen thermostat.

Mercury thermostats started it all, and were ingenious in their simplicity — a glass capsule containing mercury, attached to a wound bi-metal strip. As the temperature changes, the contraption tilts and the mercury bead moves, making or breaking contact with the wiring. More sophisticated thermostats have replaced the mercury bead with electronics, but the signaling method remains the same, just a simple contact switch.

This makes the thermostat the prime target for an aspiring home automation hacker. I’ve had this particular project in mind for quite some time, and was excited to dive into it with simple raw materials: my Raspberry Pi, a touchscreen, and a mechanical relay board.

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The FAA Mandates External Registration Markings For Drones

Drone fliers in the USA must soon display their registration markings on the exterior of their craft, rather than as was previously acceptable, in accessible interior compartments. This important but relatively minor regulation change has been announced by the FAA in response to concerns that malicious operators could booby-trap a craft to catch investigators as they opened it in search of a registration. The new ruling is effective from February 25th, though they are inviting public comment on it.

As airspace regulators and fliers across the world traverse the tricky process of establishing a safe and effective framework for multirotors and similar craft we’ve seen a variety of approaches to their regulation, and while sometimes they haven’t made complete sense and have even been struck down in the courts, the FAA’s reaction has been more carefully considered than that in some other jurisdictions. Rule changes such as this one will always have their detractors, but as an extension of a pre-existing set of regulations it is not an unreasonable one.

It seems inevitable that regulation of multirotor flight will be a continuing process, but solace can be taken at the lower end of the range. A common theme across the world seems to be a weight limit of 250 g for otherwise unrestricted and unregistered craft, and the prospects for development in this weight category in response to regulation are exciting. If a smaller craft can do everything our 2 kg machines used to do but without the burden of regulation, we’ll take that.

New Kinect Sensor Switch Focus From Gamers To Developers

Microsoft’s Kinect may not have found success as a gaming peripheral, but recognizing that a depth sensor is too cool to leave for dead, development continued even after Xbox gaming peripherals were discontinued. This week their latest iteration emerged and we can get it in the form of Azure Kinect DK. This is a developer’s kit focused on exploring new applications for this technology, not a gaming peripheral we had to hack before we could use in our own projects.

Packaged into a peripheral that plugs into a PC via USB-C, it is more than the core depth sensor module announced last year but less than a full consumer product. Browsing its 10-page specification (PDF) with comparisons to second generation Kinect sensor bar, we see how this technology has evolved. Physical size and weight has dropped, as has power consumption. Auxiliary capabilities has improved with an expanded microphone array, IMU with gyro in addition to accelerometer, and the RGB camera has been upgraded to 4K resolution.

But the star of the show is a new continuous-wave time-of-flight depth sensor, presented at the 2018 IEEE ISSCC conference. (Full text requires IEEE membership, but a digest form is available via ResearchGate.) Among its many advancements, we expect the biggest impact to be its field of view. Default of 75 x 65 degrees is already better than its predecessors (64 x 45 for first generation Kinect, 70 x 60 for second) but there is an option to trade resolution for coverage by switching to a wide-angle mode of 120 x 120 degrees. Significantly wider than other depth cameras like Intel’s RealSense D400 series or Occipital’s Structure.

Another interesting feature is built-in synchronization. Many projects using multiple Kinect sensors ran into problems because they interfered with each other. People hacked around the problem, of course, but now they don’t have to: commodity 3.5 mm jacks allow multiple Azure Kinect DK to be daisy chained together so they play nicely and take turns.

From its name we were worried this product would require Microsoft’s Azure cloud service in some way and be crippled without it. Based on information released so far, it appears developers have access to all the same data streams as previous sensors. Azure tie-in takes the form of optional SDKs that make it easier to do things like upload data for processing in Azure cloud-based recognition services.

And finally, Azure Kinect DK’s price tag of $399 is significantly higher than a Kinect game peripheral, but it is a low volume product for developers. Perhaps high volume consumer products built on this technology will cost less, but that remains to be seen. In the meantime, you have alternative tools for solving similar problems. For example if you are building your own AR headset, you might use Intel’s latest RealSense camera for vision based inside-out motion tacking.

Noise: It Turns Out You Need It

We don’t know whether quantum physics proves the universe is truly a strange place or that we are living in a virtual reality simulation, but we know it turns a lot of common sense into garbage. Take noise, for example. Noise — as in random electrical noise — is bad, right? We spend a lot of time designing to minimize noise. Researchers in Austria, Germany, and Australia recently published a paper that shows that noise can actually improve the flow of energy. While the paper is behind a paywall, the Focus article is available and, of course, you can probably find a copy of the paper if you want to read the entire thing.

The paper, titled “Environment-Assisted Quantum Transport in a 10-qubit Network” uses trapped calcium atoms to study an effect suspected of being a key factor in high-efficiency energy transfer such as the transfer observed in optical fibers and photosynthesis.

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Don’t Need A Weatherman To Know Which Way The Wind Blows On Mars

NASA’s latest Mars lander has a very precise weather package, and you can check the daily conditions on Elysium Planitia online. The data however has apparently led to a bit of a mystery. According to Ars Technica, every day at 7AM and 7PM local time, there’s an unexplained atmospheric pressure spike.

The TWINS (Temperature and Wind for InSight) package provided by Spain’s Centro de Astrobiología shows the little spikes regularly since the lander hit the ground in November. They seem to correspond to local sunrise and sunset. Keep in mind, the pressure on Mars is very low — about 1% of Earth’s atmosphere — and scientists have already ruled out instrument problems.

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The Woeful World Of Worldwide E-Waste

How large is the cache of discarded electronics in your home? They were once expensive and cherished items, but now they’re a question-mark for responsible disposal. I’m going to dig into this problem — which goes far beyond your collection of dead smartphones — as well as the issues of where this stuff ends up versus where it should end up. I’m even going to demystify the WEEE mark (that crossed out trashcan icon you’ve been noticing on your gadgets), talk about how much jumbo jets weigh, and touch on circular economies, in the pursuit of better understanding of the waste streams modern gadgets generate.

Our lives are encountering an increasing number of “how do I dispose of this [X]” moments, where X is piles of old batteries, LCDs, desktop towers, etc. This leads to relationship-testing piles of garbage potential in a garage or the bottom of a closet. Sometimes that old gear gets sold or donated. Sometimes there’s a handy e-waste campaign that swings through the neighborhood to scoop that pile up, and sometimes it eventually ends up in the trash wrapped in that dirty feeling that we did something wrong. We’ve all been there; it’s easy to discover that responsible disposal of our old electronics can be hard.

Fun fact: the average person who lives in the US generates 20 kg of e-waste annually (or about 44 freedom pounds). That’s not unique, in the UK it’s about 23 kg (that’s 23 in common kilograms), 24 kg for Denmark, and on and on. That’s quite a lot for an individual human, right? What makes up that much waste for one person? For that matter, what sorts of waste is tracked in the bogus sounding e-waste statistics you see bleated out in pleading Facebook posts? Unsurprisingly there are some common definitions. And the Very Serious People people at the World Economic Forum who bring you the definitions have some solutions to consider too.

We spend a lot of time figuring out how to build this stuff. Are we spending enough time planning for what to do with the gear once it falls out of favor? Let’s get to the bottom of this rubbish.
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Biodegradable Implants Supercharge Nerve Regeneration

Controlled electrical stimulation of nerves can do amazing things. It has been shown to encourage healing and growth in damaged cells of the peripheral nervous system which means regaining motor control and sensation in a shorter period with better results. This type of treatment is referred to as an electroceutical, and the etymology is easy to parse. The newest kid on the block just finished testing on rat subjects, applying electricity for one, three, or six days per week in one-hour intervals. The results showed that more treatment led to faster healing. The kicker is that the method of applying electricity was done through unbroken skin on an implant that dissolves harmlessly.

The implant in question is, at its most basic, an RFID tag with leads that touch the injured nerves. This means wireless magnetic coupling takes power from an outside source and delivers it to where it is needed. All the traces on are magnesium. There is a capacitor with silicon dioxide sandwiched between magnesium, and a diode made from a doped silicon nanomembrane. All this is encased in a biodegradable substrate called poly lactic-co-glycolic acid, a rising star for FDA-approved polys. Technologically speaking, these are not outrageous.

These exotic materials are not in the average hacker’s hands yet, but citizen scientists have started tinkering with the less invasive tDCS and which is applying a small electrical current to the brain through surface electrodes or the brain hacking known as the McCollough effect.

Via IEEE Spectrum.