This weekend project will tell you when you’ve got something new to look at on your Facebook page (translated). The yellow flag on the side of the mini-mailbox automatically goes up, alerting you to your recent online popularity.
[Rocco’s] craftwork on this project is fantastic. We love the scale, the colors, and especially the artificial grass that adorns the base. Inside the mailbox an Arduino controls a small servo motor attached to the new mail flag. As with other Arduino-based notifiers (be it the Internet Furby, or our own troll sniffing rat) the USB connection makes it incredibly easy to convert online information to real-world signals. The client side of this is a Python script. It uses a package that we were previously unfamiliar with called mechanize. We’ve just made a cursory examination of how that package is used, but we’re going to keep it in mind as an alternative to our usual go-to package, BeautifulSoup, which tends to be a bit hairy when you’re just looking for some basic data.
Hackerspaces are always looking for novel ways to let their members know that they are open for business, and this notifier [Angus] from Make, Hack, Void recently put together is no exception.
While dumpster diving one day, he came across a fantastic-looking lab power supply from the ‘70s. He gutted it, saving the variable transformer for a future project, and started constructing his notifier. When someone enters the hackerspace, they simply set the dial on the “Space Probe” to the amount of time they expect to be there. The built-in Seeduino sends the data over Bluetooth to an OpenWRT-enabled router, which uses a couple of Lua scripts to notify members via email and Twitter.
Since almost all of the processing is done on the router side, it leaves the Arduino in the probe with little more to do than flash an LED and send ASCII status messages any time the knob is turned. [Angus] is well aware that this would probably make most people’s heads spin, but he hopes that other hackerspace members use that untapped potential to further enhance the notifier.
Stick around to see the Space Probe in action, and if you are interested in seeing what other hackerspaces use to keep their members in the know, check out this status switch from Hack42.
Continue reading “Wireless hackerspace status notifier”
[Quinn] over at BlondiHacks is admittedly pretty absent-minded when it comes to household chores such as emptying the dishwasher. She often can’t remember if the dishes are dirty or ready to be put away, so she decided it was time to devise a mechanism that would help keep her on task. She originally considered a double-sided sign that said “Clean” on one side, “Dirty” on the other, but she chose the fun option and decided to over-engineer the problem instead.
She ultimately focused on two conditions that she needed to monitor: when the dishwasher had been run, and when the dishes have been emptied. To tackle the first condition, she used a thermistor to detect when the door of the dishwasher got hot from the wash cycle. The second wasn’t quite as easy, since she often peeks into the dishwasher to grab a clean dish when needed, unloading the rest later. She eventually settled on using a tilt switch to monitor the angle of the door, assuming that the dishes have been removed if the door was open for over a minute.
[Quinn] reports that her Dish-o-Tron 6000 works well, and she had a good time building it. Sure the whole thing is kind of overkill, but where’s the fun in moderation?
[Knuckles904] was tired of waiting for the bus. His town had installed GPS units on the buses so that riders could track their locations via the Internet so he knew there should be a way to avoid the wait while also never missing the bus. He developed a sketch for an Arduino to check the bus location and notify him when it was on its way.
This method saves him from leaving his computer running. It parses the text data from the public transportation website and updates both an LED display, as well as a Twitter feed. Now he can monitor several different bus lines via the hardware at home, or though a cell phone if he’s on the go.
Giving us a chance to break out the TLAs, [Blair] sent in his latest hack where he embedded an RGB LED into his EeePC to display twitter, pidgin, and email notifications. It is based around the ATtiny45, and requires very few additional parts. He based the project on a foundation of work laid by [Dennis Schulze] on notifications and the work of [Dave Hillier] that used V-USB, a library for implementing USB on AVRs. The entire circuit was done freehand and crammed inside the netbook. He says that it is a lot easier to see notifications, even when the laptop is shut.
Related: Email notification via RGB LED
tom horsley got rid of his land line but didn’t want to lug his cell everywhere with him when he was in the house. his solution was to hack together a light detection circuit, a wireless doorbell remote, and some paper mache into a giant incoming call noisemaker. if you want to build your own, you should also check out version 2 that he is working on.
Continue reading “cellphone ring notifier”
Traffic lights are so ubiquitous that we hardly give them a second thought, except to curse their existence when they impede us on our daily drive. But no matter how much it seems like traffic lights have the ability to read our minds and tell when we’re running late, they’re really not much more than a set of lights and a programmable controller. Simple in practice, but as usual, the devil is in the details, and for a system that needs to work as close to 100% of the time as possible, the details are important. Let’s explore the inner workings of traffic signals.
The traffic lights and crosswalk signals at an intersection are only the public user interface, of course. The interesting stuff is going on in the control box. There’s at least one at every intersection, usually a plain metal cabinet set back from the road, sometimes camouflaged with public bills or graffiti. But inside are the guts of what makes an intersection work and keeps vehicle and foot traffic moving smoothly and safely.
Unsurprisingly, most traffic signal controls started out as purely electromechanical devices. Cabinets were chock full of synchronous motors turning timing wheels with cams to cycle the intersection’s lights through the proper sequence. One old time controller that was common up until recently was made by Econolite, and the insides are a paragon of sturdy design.
Continue reading “Intro to the North American Traffic Signal”