[domiflichi] is human and fallible. So he can’t be blamed for occasionally forgetting the laundry in one of the machines and coming back to a less than stellar result. However, while fallible, he is not powerless.
What if his washer/dryer could email or text him about his laundry? It seemed simple enough. Add a vibration sensor to the side of the machine along with some brains. When the load is done it will bother him until he comes down to push the button or There Will Come Soft Rains.
He started off with an Arduino-and-ESP8226 combination and piezo sensors. The piezos had lots of shortcomings, so he switched to accelerometers and things worked much better. We really like the way he mounts them to the side of the washer dryer using the PCB’s mounting screws as angle brackets. The case is a standard project box with some snazzy orange acrylic on the front.
It took some fiddling, but these days [domiflichi]’s clothes are fresher, his cats fed, and his appliances more aware. Video of it in operation after the break.
“The great thing about standards is that there are so many to choose from.” Truer words were never spoken, and this goes double for the hobbyist world of hardware hacking. It seems that every module, every company, and every individual hacker has a favorite way of putting the same pins in a row.
We have an entire drawer full of adapters that just go from one pinout to another, or one programmer to many different target boards. We’ll be the first to admit that it’s often our own darn fault — we decided to swap the reset and ground lines because it was convenient for one design, and now we have two adapters. But imagine a world where there was only a handful of distinct pinouts — that drawer would be only half full and many projects would simply snap together. “You may say I’m a dreamer…”
This article is about connectors and standards. We’ll try not to whine and complain, although we will editorialize. We’re going to work through some of the design tradeoffs and requirements, and maybe you’ll even find that there’s already a standard pinout that’s “close enough” for your next project. And if you’ve got a frequently used pinout or use case that we’ve missed, we encourage you to share the connector pinouts in the comments, along with its pros and cons. Let’s see if we can’t make sense of this mess.
[Pawel] has a weather station, and its nerve-center is a Raspberry Pi. He wanted to include a light sensor but the problem is, the Pi doesn’t have a built-in ADC to read the voltage off the light-dependent resistor that he (presumably) had in his junk box. You can, of course, buy I2C ADC chips and modules, but when you’ve already got a microcontroller that has ADC peripherals on board, why bother?
[Pawel] wired up a tremendously simple circuit, downloaded some I2C slave-mode code, and added an LED for good measure. It’s all up on GitHub if you’re interested.
We’re covering this because we rarely see people coding for I2C slave devices. Everyone and their mom uses I2C to connect to sensors, for which the Arduino “Wire” library or “i2c-tools” on the Pi do just fine. But what do you do when you want to make the I2C device? [Pawel]’s project makes use of TinyWireS, a slave-mode SPI and I2C library for AVR ATtiny Arduino projects.
Here, [Pawel] just wanted a light sensor. But if you’re building your own devices, the sky is the limit. What’s the most esoteric I2C sensor that you can imagine? (And is it really the case that we haven’t seen an I2C slave device hack since 2010?)
MIDI is a great tool for virtually any musician. Unless you’re a keyboard player, though, it might be hard to use it live. [Evan] recently came up with a great solution for all of the wistful guitar players out there who have been dreaming of having a MIDI interface as useful as their pianist brethren, though. He created a touchless MIDI controller that interfaces directly with a guitar.
Halloween might be over, but for some of us there’s still another pumpkin-centric holiday right around the corner to give us an excuse to build projects out of various gourds. During a challenge at a local event, [Michael] came up with a virtual cornucopia of uses for all of the squashes he had on hand and built a touch-sensitive piano with all of them.
The musical instrument was dubbed the Harpsi-Gourd and makes extensive use of the Arduino touch-sensitive libraries. Beyond that, the project was constructed to be able to fit into a standard sized upright piano. While only 15 pumpkins are currently employed, the instrument can be scaled up to 48 pumpkins. Presumably they would need to be very small for the lid of the piano to still close.
A conventional compass points north (well, to magnetic north, anyway). [Videoschmideo] wanted to make a compass that pointed somewhere specific. In particular, the compass — a wedding gift — was to point to a park where the newlywed couple got engaged. Like waking up in a fresh new Minecraft world, this is their spawn point and now they can always find their way back from the wilderness.
The device uses an Arduino, a GPS module, a compass, and a servo motor. Being a wedding gift, it also needs to meet certain aesthetic sensibilities. The device is in an attractive wooden box and uses stylish brass gears. The gears allow the servo motor to turn more than 360 degrees (and the software limits the rotation to 360 degrees). You can see a video of the device in operation, below.
Making a clock with a common microcontroller like an Arduino isn’t very difficult. However, if you’ve tried it, you probably discovered that keeping track of wall time is difficult without some external hardware. [Barzok] has a very minimal clock build. It takes a handful of LED arrays with an integrated driver, an Arduino Nano, a real-time clock module, and a voltage regulator.