Detect Elevated Carbon Monoxide (Levels)

October 14, 2018 by Brian McEvoy 27 Comments

The molar mass of carbon monoxide (CO) is 28.0, and the molar mass of air is 28.8, so CO will rise in an ambient atmosphere. It makes sense to detect it farther from the ground, but getting a tall ladder is not convenient and certainly doesn’t make for fast deployment. What do you do if you don’t care for heights and want to know the CO levels in a gymnasium or a tall foyer? Here to save the day, is the Red Balloon Carbon Monoxide Detector.

Circuit.io generates the diagram and code to operate the CO sensor and turn a healthy green light to a warning red if unsafe levels are detected. The user holds the batteries, Arduino, and light while a red balloon lifts the sensor up to fifteen feet, or approximately five ~~three~~ meters. It is an analog sensor which needs some time to warm up so it pays to be warned about that wire length and startup.

Having a CO sentinel is a wise choice for this odorless gas.

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WebSockets Embedded With The ESP8266

October 3, 2018 by Al Williams 15 Comments

It used to be that Web browsing was simple. You asked a server for some text, which was duly sent, and then formatted by your browser. Now a web page is as likely to be a full-blown application that is reading mail, editing text, or lots of other things and may use WebSockets to create a back channel to the server. Thanks to affordable hardware like the ESP8266 one of those things a modern web browser can do is sense and control the real world. [Acrobotic] has an interesting video about using WebSockets to allow a browser to talk to an ESP8266 web server in real time. You can see his simple demo in the video below.

Of course, you’ll use the usual language you use on the ESP8266 — [Acrobotic] uses C++ in the Arduino IDE. On the browser side you’ll use JavaScript, although that will be embedded in your C++ program which acts as a web server.

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A New Tilt On RC Car Controllers

October 2, 2018 by Jonathan Bennett 4 Comments

If you are a lover of all-things remote-conteolled, it’s likely that you know a thing or two about controllers. You’ll have one or two of the things, both the familiar two-joystick type and the pistol-grip variety. But had you ever considered that there m ight be another means to do it? [Andrei] over at ELECTRONOOBS has posted a guide to a tilt-controlled RC car. It is a good example of how simple parts can be linked together to make something novel and entertaining, and a great starter project for an aspiring hacker.

An Arduino Nano reads from an accelerometer over an I2C bus, and sends commands over a wireless link, courtesy of a pair of HC-12 wireless modules. Another Nano mounted to the car decodes the commands, and uses a pair of H-bridges, which we’ve covered in detail, to control the motors.

The tutorial is well done, and includes details on the hardware and all the code you need to get rolling. Check out the build and demo video after the break.

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A Better Battery Arduino

October 1, 2018 by Kerry Scharfglass 5 Comments

We’ve seen [Johan]’s AA-battery-sized Arduino/battery crossover before, but soon (we hope!) there will be a new version with more MIPS in the same unique form factor! The original Aarduino adhered to classic Arduino part choices and was designed to run as the third “cell” in a 3 cell battery holder to relay temperature readings via a HopeRF RFM69CW. But as [Johan] noticed, it turns out that ARM development tools are cheap now. In some cases very cheap and very open source. So why not update an outstanding design to something with a little more horsepower?

The Aarduino Zero uses the same big PTH battery terminals and follows the same pattern as the original design; the user sticks it in a battery holder for power and it uses an RFM69CW for wireless communication. But now the core is an STM32L052, a neat low power Cortex-M0+ with a little EEPROM onboard. [Johan] has also added a medium size serial flash to facilitate offline data logging or OTA firmware update. Plus there’s a slick new test fixture to go along with it all.

So how do you get one? Well… that’s the rub. It looks like when this was originally posted at the end of 2017 [Johan] was planning to launch a Crowd Supply campaign that hasn’t quite materialized yet. Until that launches the software sources for the Zero are available, and there are always the sources from the original Aarduino to check out.

An Enigma Wrapped In A Riddle Wrapped In A Vintage Radio

September 30, 2018 by Steven Dufresne 5 Comments

Puzzle boxes are great opportunities for hacking. You can start with a box which was originally used for something else. You get to design circuitry and controls which offer a complex puzzle for the players. And you can come up with a spectacular reward for those who solve it. [thomas.meston’s] Dr. Hallard’s Dream Transmission Box, which he created for an original party game, has all those elements.

The box was a broken 1948 National NC-33 Ham Radio purchased on eBay after a number of failed bids. Most of it was removed except for the speaker. The electronics is Arduino based, so most of the smarts are in the form of code. Potentiometers and a switch provide the mechanism for players to enter codes. And when the correct code is entered, a relay triggers an external smoke machine and turns on a laser which illuminates a party ball, rewarding the victors. And of course, there are also sound effects as well as a recorded message.

We weren’t kidding when we said puzzle boxes make great hacks. Here’s one which ignites fireworks, one made only from discrete components, and a valentine based one which makes your significant other work for their gift.

Maker Faire NY: Developing For The Final Frontier

September 28, 2018 by Tom Nardi 6 Comments

The cost of getting a piece of hardware into space is now cheaper than ever, thanks in no small part to the rapid progress that’s been made by commercial launch providers such as SpaceX. In the near future, as more low-cost providers come online, it should get even cheaper. Within a few years, we could be seeing per kilogram costs to low Earth orbit that are 1/10th what they were on the Space Shuttle. To be sure, this is a very exciting time to be in the business of designing and building spacecraft.

But no matter how cheap launches to orbit get, it’ll never be cheaper than simply emailing some source code up to the International Space Station (ISS). With that in mind, there are several programs which offer students the closest thing to booking passage on a Falcon 9: the chance to develop software that can be run aboard the Station. At the 2018 World Maker Faire in New York we got a chance to get up close and personal with functional replicas of the hardware that’s already on orbit, known in space parlance as “ground units”.

On display was a replica of one of the SPHERES free-flying satellites that have been on the ISS since 2006. They are roughly the size of a soccer ball and utilize CO2 thrusters and ultrasonic sensors to move around inside of the Station. Designed by MIT as a way to study spaceflight techniques such as docking and navigation without the expense and risk of using a full scale vehicle, the SPHERES satellites are perhaps the only operational spacecraft to have never been exposed to space itself.

Expansion port for additional hardware.

MIT now runs the annual “Zero Robotics” competition, which tasks middle and high school students with solving a specific challenge using the SPHERES satellites. Competitors run their programs on simulators until the finals, which are conducted using the real hardware on the ISS and live-streamed to schools.

We also saw hardware from “Quest for Space”, which is a company offering curricula for elementary through high school students which include not only the ground units, but training and technical support when and if the school decides to send the code to the matching hardware on the Station. For an additional fee, they will even work with the school to design, launch, and recover a custom hardware experiment.

Their standard hardware is based on off-the-shelf platforms such as Arduino and LEGO Mindstorms EV3, which makes for an easy transition for school’s existing STEM programs. The current hardware in orbit is setup for experiments dealing with heat absorption, humidity, and convection, but “Quest for Space” notes they change out the hardware every two years to provide different experiment opportunities.

Projects such as these, along with previous efforts such as the ArduSat, offer a unique way for the masses to connect with space in ways which would have been unthinkable before the turn of the 21st century. It’s still up for debate if anyone reading Hackaday in 2018 will personally get a chance to slip Earth’s surly bonds, but at least you can rest easy knowing your software bugs can hitch a ride off the planet.

DIY Puff-Suck Interface Aims For Faster Text Input

September 25, 2018 by Donald Papp 9 Comments

Puff and Suck (or Sip and Puff) systems allow people with little to no arm mobility to more easily interact with computers by using a straw-like unit as an input device. [Ana] tells us that the usual way these devices are used to input text involves a screen-based keyboard; a cursor is moved to a letter using some method (joystick, mouse emulator, buttons, or eye tracking) and that letter is selected with a sip or puff into a tube.

[Ana] saw such systems as effective and intuitive to use, but also limited in speed because there’s only so fast that one can select letters one at a time. That led to trying a new method; one that requires a bit more work on the user’s part, but the reward is faster text entry. The Puff-Suck Interface for Fast Text Input turns a hollow plastic disk and a rubber diaphragm into bipolar pressure switch, able to detect three states: suck, puff, and idle. The unit works by having an IR emitter and receiver pair on each side of a diaphragm (one half of which is shown in the image above). When air is blown into or sucked out of the unit, the diaphragm moves and physically blocks one or the other emitter-receiver pair. The resulting signals are interpreted by an attached Arduino.

How does this enable faster text input? By throwing out the usual “screen keyboard” interface and using Morse code, with puffs as dots and sucks as dashes. The project then acts as a kind of Morse code keyboard. It does require skill on the user’s part, but the reward is much faster text entry. The idea got selected as a finalist in the Human-Computer Interface Challenge portion of the 2018 Hackaday Prize!

Morse code may seem like a strange throwback to some, but not only does the bipolar nature of [Ana]’s puff-suck switch closely resemble that of Morse code input paddles, it’s also easy to learn. Morse code is far from dead; we have pages of projects and news showing its involvement in everything from whimsical projects to solving serious communication needs.