three sensory bridge audio spectrum analyzers, one in use with a lit LED array plugged in, the other facing the camera and leaning against the third, all on a table

The Sensory Bridge Is Your Path To A Desktop Rave

September 26, 2022 by 7 Comments

[Lixie Labs] are no strangers to creating many projects with LEDs or other displays. Now they’ve created a low latency music visualizer, called the Sensory Bridge, that creates gorgeous light shows from music.

The Sensory Bridge has the ability to update up to 128 RGB LEDs at 60 fps. The unit has an on-board MEMS microphone that picks up ambient music to produce the light show. The chip is an ESP32-S2 that does Fast Fourier Transform trickery to allow for real-time updates to the RGB array. The LED terminal supports the common WS2812B LED pinouts (5 V, GND, DATA). The Sensory Bridge also has an “accessory port” that can be used for hardware extensions, such as a base for their LED “Mini Mast”, a long RGB array PCB strip.

The unit is powered by a 5 V 2 A USB-C connector. Different knobs on the device adjust the brightness, microphone sensitivity and reactivity of the LED strip. One of the nicer features is its “noise calibration” that can record ambient sound and subtract off the background noise frequency components to give a cleaner music signal. The Sensory Bridge is still new and it looks like some of the features are yet to come, like WiFi communication, accessory port upgrades and 3.5 mm audio input to bypass the on-board microphone.

The stated goals of the Sensory Bridge are to provide an open, powerful and flexible platform. This can be seen with their commitment to releasing the project as open source hardware, providing firmware, PCB design files and even the case STLs under a libre/free license. Audio spectrum analyzers are a favorite of ours and we’ve seen many different iterations ranging from ones using Raspberry Pis to others use ESP32s.

Video after the break!

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An image of the track system of the Calico wearable on top of a garment. Different possible positions of the device (elbow, shoulder, etc) are shown by red dots overlayed on the top of the image.

The Calico Wearable Rides The Rails

September 14, 2022 by 12 Comments

If you’re feeling underwhelmed by yet another smartwatch announcement, then researchers at the University of Maryland may have just the wearable for you. Instead of just tracking your movement from one spot, Calico winds around you like a cartoon sidekick.

Using a “railway system,”(PDF) the Calico can travel around a garment to get better telemetry than if it were shackled to a wrist. By moving around the body, the robot can track exercise, teach dance moves, or take up-close heart measurements. Tracks can be magnetically linked across garments, and Calico can use different movement patterns to communicate information to the user.

This two-wheeled robot that rides the rails is built around a custom PCB with a MDBT42Q microcontroller for a brain which lets it communicate with a smartphone over Bluetooth Low Energy. Location is monitored by small magnets embedded in the silicone and plastic living hinge track, and it can use location as a way to provide “ambient visual feedback.”

The researchers even designed a friendly cover for the robot with googly eyes so that the device feels more personable. We think animated wearables could really take off since everyone loves cute animal companions, assuming they don’t fall into the uncanny valley.

If you love unusual wearables as much as we do, be sure to check out Wearable Sensors on Your Skin and the Wearable Cone of Silence.

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A display in a field showing the water stress index over time

Hackaday Prize 2022: Using Infrared Thermometers To Measure Crops’ Water Stress

September 11, 2022 by 6 Comments

If you live anywhere on the Northern Hemisphere, you’re likely to have experienced one of the many heatwaves that occurred this summer. Extreme heat is dangerous for humans and animals, but plants, including important crops, also suffer. High temperatures lead to increased transpiration and evaporation, and if the water lost in this way is not replenished quickly enough, plants will stop growing and eventually wither and die.

In order to keep track of the amount of water available to crops, [Florian Ellsäßer] built the Crop Water Stress Sensor: a device that checks whether plants have enough moisture available to stay healthy. It does this by measuring the temperature of the leaves to calculate evaporation levels. If the leaves are cooler than their surroundings, this means that water is evaporating from them and the plant apparently has enough water available. If the leaves’ temperature is closer to the ambient temperature, then the plant may be running low on water.

[Florian]’s system performs this measurement using an infrared array, which is basically a low-resolution thermal camera that remotely measures the temperature of everything in its field of view. This IR array is pointed at a field, where it will see both leaves and the ground between them. The difference in temperature between these two can then be used to calculate the Crop Water Stress Index (CWSI), a standardized measure of how well-hydrated plants are. The result is shown on a display and also indicated using a convenient red-yellow-green status LED that shows if the crops in question need watering.

The system can be solar powered for completely remote operation, while its data can be read out through a WiFi interface. [Florian] is planning to update the design with a LoRa interface for greater range: the eventual goal is to build a large network of these sensors throughout agricultural areas and use the combined data to raise awareness of water shortages in certain areas. In order to make the sensors easy to build by anyone interested, all design files are available on the project page.

Keeping crops moisturized is one of the key tasks of agriculture, and we’ve seen several projects that aim to optimize and automate it, from a simple-but-effective ESP8266-based moisture sensor to complete hydroponics systems.

An opened plastic project box with electronics inside

Smoking Meat Finds Natural Home In The Cloud

August 9, 2022 by 15 Comments

Did you know that backyard barbecues now come with WiFi? It should be no surprise, given the pervasiveness of cloud-enabled appliances throughout the home. However [Carl] wasn’t ready to part with his reliable but oh-so-analog BBQ smoker, so instead he created an affordable WiFi-based temperature monitor that rivals its commercial counterparts.

Accurate temperature measurement is essential to smoking meat from both a taste and safety standpoint. In this project, two Maverick ET-732/733 thermistor probes take care of the actual temperature monitoring. One probe is skewered into meat itself, and the other measures the ambient ‘pit’ temperature. Combined, these two gauges ensure that the meat is smoked for exactly the right length of time. [Carl] mentions that adding an extra temperature sensor is trivial for larger setups, but he’s getting by just fine with two data points.

Naturally an ESP8266 does most of the heavy lifting in bridging the gap between smoke and cloud. At the core of this project is utility and practicality – temperature statistics can be viewed on any device with a web browser. Being able to study the temperature trends in this way also makes it easier to predict cooking times. Electronic alerts are also used to notify the chef if the temperature is too hot or cold (among other things). The entire contraption is housed in a smart looking project box that contains an LCD and rotary encoder for configuration.

If this has piqued your culinary interest, check out the extensive documentation recipe over on GitHub and the project Wiki.  We also recommend checking out this project that takes automated meat smoking to the next level.

The Benefits Of Displacement Ventilation

July 7, 2022 by 27 Comments

The world has been shaken to its core by a respiratory virus pandemic. Humanity has been raiding the toolbox for every possible weapon in the fight, whether that be masks, vaccinations, or advanced antiviral treatments.

As far as medicine has come in tackling COVID-19 in the past two years, the ultimate solution would be to cut the number of people exposed to the pathogen in the first place. Improving our ventilation methods may just be a great way to cut down on the spread. After all, it’s what they did in the wake of the Spanish Flu.

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Berlin Clock Takes Inspiration From Sci-Fi Sources, Looks Incredible

July 7, 2022 by 6 Comments

What would a HAL9000 look like if it eye were yellow and sat atop a front panel inspired by an Altair 8800? You’d have today’s feature, [Stephan]’s BerlinUhr, a gorgeous little take on a Berlin Clock.

At Hackaday, we have a soft spot for clock builds. They’ve graced our pages from early times. When we saw this ultra cool Berlin Clock, we couldn’t resist the urge to share it with all of our readers.  For those of you not familiar with a Berlin Clock, it’s a clock that consists of 24 lights, and was the first of its kind back in 1975.

[Stephan]’s build is notable because not only is it a beautiful design, but the work that went into the design and build. At several inches tall, the BerlinUhr is supported solely by a USB-C connection, although it can also be hung on a wall. The RTC is backed up by a CR1216, and an ATtiny167 provides the brains for the operation.

A neat part of the build comes with the KPS-3227 light sensor, used to adjust the LED brightness according to ambient lighting. Rather than being a straightforward part to insert into the PCB, KiCad’s footprint had some pins reversed, causing [Stephan] to learn how to correct it and contribute the fix to KiCad. Well done!

We weren’t kidding about clocks, by the way- check out the link to the Atomic Wrist Watch on this post from 2005, and this Russian VFD based clock from 2006- with video!

Do you have your own favorite clock build you’d love to see grace our pages? Be sure to submit a tip!

A Handy Breakout Board For E-Paper Hacking

June 15, 2022 by 5 Comments

If you follow the exploits of [Aaron Christophel] (and trust us, you should), you’ll know that for some time now he’s been rather obsessed with electronic price tags, specifically those with e-paper displays. It’s certainly not hard to see why — these low-power devices are perfect for ambient displays, and their integrated wireless capabilities mean you can put one in every room and update them from a central transmitter.

But with such a wide array of products on the market, [Aaron] has found himself doing a lot of e-paper reverse engineering. This involves sticking a logic analyzer between the display and the tag’s microcontroller, which he found to be a rather finicky task. That’s why he created the Universal E-Paper Sniffer: a breakout PCB that lets you snoop on display communication without having to resort to unpleasant methods like scratching off the solder mask to tap into the traces by hand.

It’s a pretty simple gadget: on either side, you’ve got a connector for 24 pin 0.5 mm pitch flat flex cable, which [Aaron] has identified as the most common interface for these displays, and in the middle you’ve got a standard 2.54 mm pitch header. There are no other components on the board, and all the traces go right through to the other side.

Add a few jumpers and a cheap logic analyzer, and you’re ready to sniff some SPI commands. Check out the video after the break for a general walk-through of what it looks like to start sniffing around a new display.

The Gerber files for the breakout are available for free, or you can chose to buy a fabricated board through PCBWay to kick [Aaron] a portion of the sale price. However you get one, we think this will be a handy little tool to have around if you find yourself bitten by the price tag hacking bug.

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