Anyone who owns their own pool knows it’s not as simple as filling it up with water and jumping in whenever you want. There’s pool covers to deal with, regular cleaning with the pool vacuum and skimmers, and of course, all of the chemicals that have to be added to keep the water safe. While there are automatic vacuums, there aren’t a whole lot of options for automating the pool chemicals. [Clément] decided to tackle this problem, eliminating one more task from the maintenance of his home. (Google Translate from French.)
The problem isn’t as simple as adding a set amount of chemicals at a predetermined time. The amount of chemicals that a pool owner has to add are dependent on the properties of the water, and the amount of time that’s elapsed since the previous chemical treatment, and the number of people who have been using the water, and whether or not the pool cover is in use. To manage all of this, [Clément] used an ORP/Redox probe and a pH probe, and installed both in the filtration system. The two probes are wired to an Arduino with an ethernet shield. The Arduino controls electrically actuated chemical delivery systems that apply the required amount of chemicals to the pool, keeping it at a nice, healthy balance. Continue reading “Home Pool Added to Home Automation”→
[dmitry] writes in to let us know about a new project that combines lasers with fans and turns the resulting modulation of the light beams into an autonomous soundscape. The piece is called “divider” and is a large, wall-mounted set of rails upon which seven red lasers are mounted on one end with seven matching light sensors mounted on the other end. Interrupting the lasers’ paths are forty-two brushless fans. Four Arduino Megas control the unit.
Laser beams shining into light sensors don’t do much of anything on their own, but when spinning fan blades interrupt each laser beam it modulates the solid beams and turns the readings of the sensors on the far end into a changing electrical signal which can be played as sound. Light being modulated by fan blades to create sound is the operating principle behind a Fan Synth, which we’ve discussed before as being a kind of siren (or you can go direct to that article’s fan synth demo video to hear what kind of sounds are possible from such a system.)
This project takes this entire concept of a fan synth further by not only increasing the number of lasers and fans, but by tying it all together into an autonomous system. The lasers are interrupted repeatedly and constantly, but never simultaneously. Listen to and watch it in action in the video below.
How do you earn a place in a flower festival with a handful of Arduinos and a 3D printer? By building a water curtain that draws flowers. That’s exactly what Tecnoateneu Vilablareix, a hacking community in Spain did. They built this project specifically for Temps de Flors, a popular annual gathering in Girona, Spain. More than just a flower festival, the event opens gardens and courtyards of culturally importance to the general public that are closed the rest of the year.
The water curtain uses four Arduino Nanos to control the valves, which work in pairs to draw flowers, words, and patterns. A Mega provides a wifi connection to receive commands. Over 16 continuous days worth of print time went into the 128 valves and 64 nozzles that make up the water curtain. It took the group around 24 iterations to get the valve design just right—they have to be able to shut off quickly.
There’s an eight-video playlist after the break and a special video that shows how much we love pandering. Most of the ones in the playlist are quite short and demonstrate the final version of the water curtain. Others show the valve testing. The last is a time-lapse of the group setting it up at the festival. If you’re in the area, the festival runs until May 15th.
It’s a dream come true: remote control of a real car. Besides being a lot of fun, a life-size RC vehicle has some practical applications, like performing rescue operations or delivering supplies to dangerous areas. For [Carter], [Dave], [Ryan], and [Sean], the dream became reality in the span of 24 caffeine-and-chicken-finger-fueled hours during an Ohio State University hackathon. They dubbed the system MagiKarpet because it sits in place of the floor mat and runs on pixies.
The plan was to control the throttle, brake, and steering of a Chevy Cobalt using a PlayStation controller. For added fun, a camera mounted high above the back bumper would provide a third-person view, and this feed would be displayed on a monitor in the backseat. Everything is controlled by an Arduino Mega. A beefy linear actuator works the brake and is attached temporarily with a band of Shapelock that slips around the pedal. The throttle is pushed by a lever attached to a car window motor. Another motor connects to the steering wheel with cables that can turn it 90° left and right. Although the build was successful, they ran into a couple of issues. But what’s a hackathon experience without a few problems?
The linear actuator was jammed for about an hour after some early testing, but they got it unstuck. The PS controller was borked, so they had to roll their own joysticks. The school wouldn’t let them actually drive it around because of safety (killjoys but we get it), so they put it up on a jack to demonstrate it for the judges. They took second place, though we can’t imagine what would have beat this. Check out the complete build video after the break.
You might remember these guys from last year around this time. They took first place at the same hackathon with Robottermilk Puncakes, a app-controlled pancake machine. Now that you’re hungry for pancakes, feast your eyes on this endless one.
If you haven’t been paying attention, big wheel trikes are a thing. There are motor driven versions as well as OG pedal pushing types . [Flux Axiom] is of the OG (you only get one link, now its on you) flavor and has written an instructable that shows how to achieve some nice looking on screen data that he syncs up with the video for a professional looking finished product which you can see in the video after the break.
[Flux Axiom] is using an Arduino Mega in his setup along with a cornucopia of sensors and all their data is being logged onto an SD card. All the code used in his setup is available in his GitHub repository. [Flux Axiom] was also nice enough to include the calibration process he used for the sensors which is also located in the GitHub download.
Sadly [Flux Axiom] uses freedom hating software for combining the video and data, Race Render 3 is his current solution and he is pleased with the results. Leave it in the comments if you have an open source solution for combining the video and data that we can offer him as a replacement.
[Chris] tipped us off about a different take on the linear book scanner created by [Forssa1] that uses server fan to turn the pages. [Forssa1]’s rig is built from laser-cut acrylic and employs two handheld scanners driven by an Arduino Mega. We don’t have a great deal of information about this build, but you can check it out after the break.
This isn’t a bunch of components kludged together either. [Carsten] is an a EE and that explains a lot of the really great choices he made like buffering, opto-isolation, and the clean assembly despite a schematic that’s so busy it’s difficult figure out where to start.
So, what does it do? Looks like a one-stop-shop for quick prototyping needs. For instance, there’s a pushbutton, toggle-switch, and a couple of trimpots for quick and easy input. At the center of the board is a 7-segment display, and multiple rows of LED bar displays (assembled from SMD components and protoboard) to provide feedback to the user.
There are also a number of sensors at the party, including a mercury shake sensor, temperature sensor, microphone, thermistor, and light dependent resistor. If what you need isn’t on the board there are multiple options for connecting external gear including opto-isolated input and output, and a LEMO for digital I/O with another for analog. All of that and we forgot to mention the moving coil voltmeter that measures PWM.