Oscar Updates Your Grocery List From The Trash

November 23, 2013 by Adam Fabio 26 Comments

grocerylist

[Dan] has come up with a novel solution to the age old problem of keeping your grocery list up to date. He’s added a bar code scanner and a Raspberry Pi under a kitchen cabinet. He calls the system “Oscar”, though we don’t see any grouchiness in his trash can. When [Dan] runs out of a product, he simply throws it away. Just above his garbage and recycling bin is a low cost barcode scanner. [Dan] holds the item until the scanner reads, then sends it on it’s way to recycling or the landfill. The decoded bar code is processed by a Raspberry Pi also hiding under the cabinet. The Raspberry Pi sends the data to Trello.comusing the Trello api.

If a product isn’t recognized by Trello’s database, trello dispatches a text message to [Dan’s] phone. He can then add the product information via a web interface. We think the user interface is what’s great here. Once products are in the database, the only thing that has to be done day to day is pause for a moment before throwing a package away. [Dan] has all his code up on github, and has also created a reddit thread for Oscar.

http://www.youtube.com/watch?v=9_MNOOgFDg4

[via reddit.com]

Hack Your Stove In The Name Of Homebrewing

November 22, 2013 by Adam Fabio 10 Comments

stovehack

[Tim] is a homebrewer. Temperature profiling during the mashing process is apparently even more critical than the temperature curve of a solder reflow oven. His stove just wasn’t giving him the level of control he needed, so [Tim] added a PID temperature controller to his stove. Electric stoves generally use an “infinite switch” to control their burners. Infinite switches are little more than a resistor and a bimetallic strip in a single package. Not very good for accurate temperature control. The tricky part of this hack was to make it reversible and to have little visual impact on the stove. A stove top with wires hanging out would not only be dangerous electrically, it would also create a hazardous situation between [Tim] and his wife.

[Tim’s] brewpot only fit on the stove’s largest burner, so that was the only one that needed PID control. To keep things simple, he kept the commercial PID controller outside the stove’s enclosure. Inside the stove, [Tim] added a solid state relay. The relay is mounted to a metal plate, which screws to the back of the stove. The relay control lines run to an audio jack on the left side of the stove. Everything can be bypassed with a switch hidden on the right side of the stove. In normal operation, the switch is in “bypass” mode, and the stove works as it always has. When mashing time comes along, [Tim] flips the switch and plugs the jack into his PID controller. The temperature sensor goes into the brewpot itself, so no stove modification was needed there.

The end result is a very clean install that both [Tim] and his wife can enjoy. Save a few bottles for us, [Tim]!

DIY Bluetooth Home Automation

November 17, 2013 by James Hobson 20 Comments

blueboard

Interested in a bit of home automation? Don’t know where to start? We just found a great Instructable on making your own bluetooth controlled relay module!

[Kyle’s] been working on this for a while, and finally at his 5th iteration he’s ready to share it with the public. It’s a project you can make from scratch, and each unit will cost approximately ~$25 in components — which can control up to two outputs. He’s included an inkscape PCB layout which you can easily etch on your own using the toner transfer method. The heart of the build is an Atmega328, which helps keep the costs down — after all, it is only controlling two outputs! Then it’s just a matter of adding the components, a bit of soldering, and uploading the firmware!

The entire design is open source, and [Kyle] would love some feedback to continue improving upon it. The write-up is quite thorough, so if you’re interested, take a look and leave him a comment!

Arduino-Based Power Failure Alert System

November 17, 2013 by Marsh 23 Comments

arduinoPowerFailBox

When the power went out at his parents’ shop and ruined the contents of their fridge, [Lauters Mehdi] got to work building a custom power failure alert system to prevent future disasters. Although some commercial products address this problem, [Lauters] decided that he could build his own for the same cost while integrating a specific alert feature: one that fires off an SMS to predefined contacts upon mains power failure.

The first step was to enable communication between an Arduino Micro and a Nokia cell phone. His Nokia 3310 uses FBus protocol, but [Lauters] couldn’t find an Arduino library to make the job easier. Instead, he prototyped basic communication by running an Arduino Uno as a simple serial repeater to issue commands from the computer directly to the phone, and eventually worked out how to send an SMS from the ‘duino. [Lauters] then took the phone apart and tapped into the power button to control on/off states. He also disconnected the phone’s battery and plugged it into an attached PCB. The system operates off mains power but swaps to a 1000mAH 9V backup battery during a power outage, logging the time and sending out the SMS alerts. A second message informs the contacts when power has been restored.

Head over to [Lauters’s] project blog for schematics and photos, then see his GitHub for the source code. If you want to see other SMS hacking projects, check out the similar build that keeps a remote-location cabin warm, or the portable power strip activated by SMS.

20 Android Tablets Form An Interactive Photo Collage

November 15, 2013 by Marsh 20 Comments

You might not have a small army of unused tablets lying around, but if you did, you should try turning them into what Minn calls a “Giant Interactive Photo Array Display:” A Giant IPAD. Har har.

[Minn’s] first step was to hit eBay, hoping to find a score of low-priced, broken-yet-easily-repairable tablets. The only ones available (and for cheap), however, were resistive touch screens with narrow viewing angles. After waiting patiently for nearly half a year, [Minn] hit the capacitive touch jackpot: snagging a pile of 10″ and 7″ Android tablets. The frame is custom made to provide a solid surface for mounting and enough depth for the tablets to fit correctly. Rather than form his own brackets to hold each device, [Minn] re-purposed some IKEA cupboard handles, screwing them into the MDF backboard and clamping the tablets to them with bolts that press against the case. An adhesive rubber bumper stuck to the top of the bolts prevents any damage.

Providing power to the diverse collection required another custom solution; two 5V 10A supplies and one 9V 16A supply fit into an accompany box safely deliver the needed juice. [Minn] chose an app that will grab photos from cloud storage so he can update the collection without having to dig around inside the frame. See the result in a video below! Want to try this project but only have one tablet to spare? The in-wall tablet mount might help.

Continue reading “20 Android Tablets Form An Interactive Photo Collage” →

Automated Aquarium Is Kitchen-Sinky

November 15, 2013 by Marsh 16 Comments

fishtankAutomation

People have been converting their old Power Macs and Mac G5s into fish tanks for a few years now, but [Hayden’s] Internet-enabled tank is probably the most awesome ever crammed into an aquarium along with the water and the fish—and we’ve seen some fascinating builds this summer. After gutting the G5 and covering the basic acrylic work, [Hayden] started piling on the electronics: a webcam, timed LED lighting, an LCD for status readouts, filter and bubble control via a servo, an ultrasonic sensor to measure water levels, thermometer, scrolling matrix display, an automatic feeding mechanism, and more. He even snuck in the G5’s old mainboard solely for a cool backdrop.

The build uses both a Raspberry Pi and an Arduino Mega, which sit underneath the tank at the base. The Pi provides a web interface written in PHP and jQuery, which presents you with the tank’s status and allows changes to some settings. Nearly every component received some form of modification. [Hayden] stripped the webcam of its case and replaced the enclosure with a piece of acrylic and a mountain of silicone, making it both waterproof and slim enough to fit in the appropriate spot. Though he decided to stick with an Amazon-bought Eheim fish feeder, he disabled the unit’s autofeed timer and tapped in to the manual “feed” button to integrate it into his own system.

It’d take half of the front page to explain the rest of this thing. We’ve decided to let the aquarium tell you the rest of its features in the video below. Yeah…it can talk.

Continue reading “Automated Aquarium Is Kitchen-Sinky” →

Arduino Astronomic Clock Automates Lights

November 15, 2013 by Marsh 32 Comments

[Paulo’s] garden lights are probably a bit more accurately automated than anyone else’s on the block, because they use latitude and longitude clock to decide when to flip the switch. [Ed Note from the far future: this page no longer exists, but you can still read it on the Wayback Machine. The TimeLord library has also been superceded, so you’ll have some porting to do.]

Most commercial options (and hobbiest creations) rely on mechanical on/off timers that click on an off every day at the same time, or they use a photosensitive element to decide it’s dark enough. Neither is very accurate. One misplaced leaf obscuring your light-dependent resistor can turn things on unnecessarily, and considering the actual time of sunset fluctuates over the year, mechanical switches require constant adjustment.

[Paulo’s] solution addresses all of these problems by instead relying on an algorithm to calculate both sunrise and sunset times, explained here, combined with swiftek’s Timelord library for the Arduino. The build features 4 7-segment displays that cycle through indicating the current time, time of sunset and of sunrise. Inside is a RTC (real time clock) with battery backup for timekeeping along with an Omron 5V relay to drive the garden lamps themselves. This particular relay comes with a switch that can force the lights on, just in case.

Check out [Paulo’s] project blog for the full write-up, links to code and more details, then take a look at some other home automation projects, like the SMS-based heater controller or occupancy-controlled room lighting.