The Smart Humidor


If you’re a cigar aficionado, you know storing cigars at the proper temperature and humidity is something you just need to do. Centuries of design have gone into the simple humidor, and now, I guess, it’s time to put some electronics alongside your cigars.

The design of [dzzie]‘s smart humidor consists of an Arduino, WiFi shield, LCD + button shield, and most importantly, a DHT22 temperature and humidity sensor. In a bit of thoughtfulness, only the DHT22 is mounted inside the humidor; everything else is in an enclosure mounted outside the humidor, including a few buttons for clearing alerts and logging when water is added.

The smart humidor reads the DHT22 sensor every 20 minutes and uploads the data to a web server where useful graphs are rendered. The control box will send out an alert email to [dzzie] if the temperature or humidity is out of the desired range.

Hackaday Links: July 27, 2014


Taking apart printers to salvage their motors and rods is a common occurrence in hacker circles, but how about salvaging the electronics? A lot of printers come with WiFi modules, and these can be repurposed as USB WiFi dongles. Tools required? And old printer, 3.3 V regulator, and a USB cable. Couldn’t be simpler.

The Raspberry Pi has a connector for a webcam, and it’s a very good solution if you need a programmable IP webcam with GPIOs. How about four cameras?. This Indiegogo is for a four-port camera connector for the Raspi. Someone has a use for this, we’re sure.

The one flexible funding campaign that isn’t a scam. [Kyle] maintains most of the software defined radio stack for Arch Linux, and he’s looking for some funds to improve his work. Yes, it’s basically a ‘fund my life’ crowdfunding campaign, but you’re funding someone to work full-time on open source software.

Calibration tools for Delta 3D printers. It’s just a few tools that speed up calibration, made for MATLAB and Octave.

[Oona] is doing her usual, ‘lets look at everything radio’ thing again, and has a plan to map microwave relay links. If you’ve ever seen a dish or other highly directional antenna on top of a cell phone tower, you’ve seen this sort of thing before. [Oona] is planning on mapping them by flying a quadcopter around, extracting the video and GPS data, and figuring out where all the other microwave links are.

PowerPoint presentations for the Raspberry Pi and BeagleBone Black. Yes, PowerPoint presentations are the tool of the devil and the leading cause of death for astronauts*, but someone should find this useful.

* Yes, PowerPoint presentations are the leading cause of death for astronauts. The root cause of the Columbia disaster was organizational factors that neglected engineer’s requests to use DOD space assets to inspect the wing, after which they could have been rescued. These are organizational factors were, at least in part, caused by PowerPoint.

Challenger was the same story, and although PowerPoint didn’t exist in 1986, “bulletized thinking” in engineering reports was cited as a major factor in the disaster. If “bulletized thinking” doesn’t perfectly describe PowerPoint, I don’t know what does.

As far as PowerPoint being the leading cause of death for astronauts, 14 died on two shuttles, while a total of 30 astronauts died either in training or in flight.

An Automated Flappy Bird Player

game Flappy Bird has been ported to just about every system imaginable, including but not limited to the Apple II, Commodores, pretty much every version of the Atari, and serves as a really great demonstration of the TI-99′s graphics capabilities. Porting is one thing, but having a computer automate Flappy Bird is another thing entirely. [Ankur], [Sai], and [Ackerly] in [Dr. Bruce Land]‘s advanced microcontroller design class at Cornell have done just that. They’re playing Flappy Bird with a camera, FPGA, and a penny wired up to a GPIO pin to guide the little 8-bit-bird through Mario pipes.

The setup the team is using consists of a webcam that records the screen of a smartphone, an FPGA, and a little bit of circuitry to emulate screen taps. Inside the FPGA, the team is looking at the video stream from the phone to detect the bird, pipes, and gaps. The ‘tapper’ unit is a US penny, placed right above the ‘tap’ button, wired to a GPIO port. This was found to be the ideal contact for a capacitive touch screen – taps that were too small weren’t registered, and taps that were too big registered as two taps.

For spending an entire semester on automating Flappy Bird, the team has a lot of knowledge to show for it, but not the high score: the bird only makes it through the first pipe 10% of the time, and the second pipe 1% of the time. The high score is three. That’s alright – getting the algorithm right to play the game correctly was very, very difficult, and to nail that problem down, they estimate it would take at least another semester.

Enjoying The Sunrise Every Single Day


[Andy] wanted to take a few at sunrise, but waking up before sunrise has obvious problems associated with it. Instead, he built a device that calculates the local sunrise time, snaps a picture, and goes to sleep until the next morning.

The camera used for the project was an old Canon point and shoot, chosen for the ability to load CHDK firmware. Other electronics included an Arduino pro mini, a LiPo battery and charger board, real time clock, and an old Nokia LCD for the user interface.

There’s quite a bit of code that goes into figuring out when the sun will rise each day, but once that’s figured out, all [Andy] has to do is take the camera somewhere pretty, point it East, and record a few days worth of sunrises. When put into a ‘game camera’ enclosure, its rugged enough to stand up to everything except a thief, and has enough battery power for a few weeks worth of sunrises.

Video demonstrating the local sunrise time below.

[Read more...]

A Router-Based Dev Board That Isn’t A Router

Here’s somethirouterng that be of interest to anyone looking to hack up a router for their own connected project or IoT implementation: hardware based on a fairly standard router, loaded up with OpenWRT, with a ton of I/O to connect to anything.

It’s called the DPT Board, and it’s basically an hugely improved version of the off-the-shelf routers you can pick up through the usual channels. On board are 20 GPIOs, USB host, 16MB Flash, 64MB RAM, two Ethernet ports, on-board 802.11n and a USB host port. This small system on board is pre-installed with OpenWRT, making it relatively easy to connect this small router-like device to LED strips, sensors, or whatever other project you have in mind.

The board was designed by [Daan Pape], and he’s also working on something he calls breakoutserver There’s a uHTTP server written specifically for the board that allows any Internet connected device to control everything on the board. There’s also an HTML5 app they’re developing which could be pretty interesting.

All in all, it’s a pretty cool little device that fits nicely in between the relatively simplistic ‘Arduino with an Ethernet shield’ and a Raspi or BeagleBone.

Ask Hackaday: Graphene Capacitors On Kickstarter

Last week, we heard of an interesting Kickstarter that puts a capacitor and charging circuit in the same space as a AA battery. This is usually a very simple endeavour, but this capacitor has the same energy density as an alkaline cell. The chemistry inside this capacitor was initially attributed to lithium ion, and a few people in the comments section were wondering how this was possible. The math just didn’t seem to add up.

The guy behind this Kickstarter, [Shawn West], recently spilled the beans on these… interesting capacitors. Apparently, they’re not lithium ion capacitors at all, but graphene capacitors. Graphene capacitors you can buy. On Kickstarter. Graphene capacitors, also known as the thing that will change everything from smartphones to electric vehicles, and everything in between. I will admit I am skeptical of this Kickstarter.

Apparently, these graphene supercaps are in part designed and manufactured by [Shawn] himself. He fabricates the graphene by putting graphite powder in a ball mill for a day, adding a bit of water and surfactant, then running the ball mill for another few days. The graphene then floats to the top where it is skimmed off and applied to a nonconductive film.

There’s absolutely nothing that flies in the face of the laws of physics when it comes to graphene capacitors – we’ve seen a few researchers at UCLA figure out how to make a graphene supercap. The general consensus when it comes to graphene supercaps is something along the lines of, ‘yeah, it’ll be awesome, in 10 years or so.’ I don’t think anyone thought the first graphene capacitors would be available through Kickstarter, though.

I’m a little torn on this one. On one hand, graphene supercaps, now. On the other hand, graphene supercaps on Kickstarter. I’m not calling this a scam, but if [Shawn]‘s caps are legit, you would think huge companies and governments would be breaking down his door to sign licensing agreements.

Post your thoughts below.

Using Surface Mount Devices On A Breadboard


[Czar] was working on a project with the Raspberry Pi using the MCP3008 analog to digital converter. The surface mount SOIC version of this chip was slightly cheaper, and there’s always a way to make that work (Portuguese, Google Translation). How [Czar] did it is fairly impressive, as it’s a bit more flexible for breadboard designs than a through-hole version, and done correctly, is an extremely sturdy hack.

A few new leads needed to be soldered onto the SOIC package, and for this [Czar] chose jumper wires. This makes each pin easy to plug into a solderless breadboard, and since [Czar] was extremely clever, all the wires for power, ground, analog, and SPI are color coded.

Simply soldering a few jumper wires onto a chip won’t last for very long. To solve this problem, [Czar] potted the entire chip and its connections with hot glue. Probably not the best solution, and a heavy-duty epoxy would have been better, but the current build is more than enough to stand up to the relatively minor abuse it will receive on the workbench.