Using Ultrasonic Sensors to Measure and Log Oil Tank Levels

[Mike] lives in a temperate rainforest in Alaska (we figured from his website’s name) and uses a 570 gallon oil tank to supply his furnace. Until now, he had no way of knowing how much oil was left in the tank and what his daily usage was. As he didn’t find any commercial product that could do what he wanted, he designed his own solution. In his write-up, [Mike] started by listing all the different sensors he had considered to measure the oil level and finally opted for an ultrasonic sensor. In his opinion, this kind of sensor is the best compromise between cost, ease of use, range and precision for his application. The precise chosen model was the ping))) bought from our favorite auction website for around $2.5.

[Mike] built the custom enclosure that you can see in the picture above using PVC parts. Enclosed are the ultrasonic sensor, a temperature sensor and an LED indicating the power status. On the other side of the CAT5 cable can be found an Arduino compatible board with an XBee shield and a 9V battery. Using another XBee shield and its USB adapter board, [Mike] can now wirelessly access the tank oil level log from his computer.

Wireless MIDI Floor Piano!


[Jianan Li] just finished documenting one of his most recent projects, a wireless MIDI floor piano that he and a small group made for Duke University’s Hackathon!

He was inspired to do this project after reading our recent coverage on a DIY Pressure Plate. Having only 24 hours to compete in the Hackathon, they had to choose something that was fairly easy to build out of cheap materials, and quick to assemble. This was just the ticket.

The piano features 25 of the aluminum foil pressure plates, whose state are read by the Arduino Mega. This is then transmitted by an XBee radio to an Arduino Uno, which acts as the receiver for the laptop that processes the signals. They even added a remote control using an ATtiny85 to allow for octave and instrument changes — it also uses an XBee to communicate back to the Uno. For a 24 hour build, the quality is quite impressive, and it doesn’t sound half bad either — Take a listen after the break!

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A Low-Cost Modular High Altitude Balloon Tracker with Mesh Networked Sensors

[Ethan] just tipped us about a project he and a few colleagues worked on last year for their senior design project. It’s a low-cost open hardware/software high altitude balloon tracker with sensors that form a mesh network with a master node. The latter (shown above) includes an ATmega644, an onboard GPS module (NEO-6M), a micro SD card slot, a 300mW APRS (144.39MHz) transmitter and finally headers to plug an XBee radio. This platform is therefore in charge of getting wireless data from the slave platforms, storing it in the uSD card while transmitting the balloon position via APRS along with other data. It’s interesting to note that to keep the design low-cost, they chose a relatively cheap analog radio module ($~40) and hacked together AFSK modulation of their output signal with hardware PWM outputs and a sine-wave lookup table.

The slave nodes are composed of ‘slave motherboards’ on which can be plugged several daughter-boards: geiger counters, atmospheric sensors, camera control/accelerometer boards. If you want to build your own system, be sure to check out this page which includes all the necessary instructions and resources.

Commodore 64 Power Glove Is So Bad


The Nintendo Power Glove was terrible. Really, really terrible. Thanks to modern components, though, it’s possible to recreate the Power Glove experience in a way that doesn’t suck so much. That’s what [Leif] did with his motion sensing glove for the Commodore 64.

Instead of rolling his own IMU and putting it in a glove, [Leif] is using SonicWear SoMo, a glove originally designed to generate MIDI data for performance pieces. Inside this glove is a 9 DOF gyro/accelerometer/magnetometer, uC, battery, and XBee that can be easily reprogrammed to do something a little more (or less) useful than simply sending MIDI notes and commands.

[Leif] reprogrammed the XBees to use I/O line passing instead of sending serial data, and connected the recieving XBee to the C64 joystick port through a very simple circuit with a hex inverter.

All the code to turn a SonicWear glove into a C64 controller is available on the Github, and there’s a neat demo video of [Leif] demoing his glove at the VCF Midwest late last month.

Hackaday Links: October 6, 2013


The iBeacon has been all over the interwebs lately. Here’s a riff on the Arduino Pro MIni that adds a BLE module. It can be used to make an iBeacon clone. You can also hack a VTag keyfinder to operate in much the same way.

Remember that post about pulling a QR Code generator into Google Docs? One could argue that the best use of this functionality is to add labels to your parts storage that lead back to the product page for the component. [Thanks Nicholas]

[Michael] wrote in to share his crowd funding campaign. He is a school teacher and wants to publish a detective story that gets kids excited about STEM.

Our own [James Hobson] made the first cut to be [Adam Savage's] new assistant. He’s the [TheHacksmith] (read our staff page if you don’t believe us) and is the third entry featured in this vignette. Apparently they’ve got something against Canadians because they say he’s ineligible due to his nationality!?

If you’ve ever been confused about the features of different Xbee modules this comparison chart may be of assistance.

A couple of weeks ago we learned about a contest put on by TheControllerProject. [TouchStone936] gets credit for quick, easy, and functional. His solution to making shoulder buttons more accessible includes hot-glue, a golf tee, and a binder clip. Pretty clever!

Wanting a better color of backlight for his eReader, [Vivek Gani] cracked it open and applied Kapton Tape as a gel to soften the hue.

And finally something very silly. If you put a strong enough prop on the front, you can get just about anything to fly. This instance involves a flying pizza box which to us looks particularly un-flight-worthy. [via Gizmodo]

A DIY Solution for Controlling Robots and Quadcopters


RC transmitters used for controlling robots, quadcopters, airplanes, and cars really aren’t that complex. There are a few switches, pots, a screen and a radio transmitter. The maker toolbox already has all these components, so it only makes sense someone would try to build their own RC transmitter.

[Oscar]‘s project started by gathering a bunch of toggle switches, 2-axis joysticks, pots, tact switches, an Arduino, LCD, and a Ciseco XRF wireless module. These were attached to a front panel made of polystyrene and work on the communications protocol began.

It should be noted that microcontroller-powered RC transmitters with XBees is nothing new. There was a Kickstarter for one last year, but the final product turned out to be bit janky and full of fail wiring, We’re really glad to see [Oscar]‘s attempt at a DIY RC transmitter, and hopefully we’ll see this project taken up and improved by others.

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DIY Pressure Plate Switch for your Haunted House

Pressure Plate

Yes, its Halloween time again and the hacks are going to be crawling out of the woodwork for the rest of the month. [Rich Osgood] is off to a good start promising one hack every week until Halloween. Judging from this first project, a DIY pressure plate switch, we think there’s going to be a common theme to follow. [Rich] constructs his pressure plate for almost no cost using cardboard, tinfoil and duct tape. It couldn’t be easier, so make lots of these if your haunting project requires pressure plate triggers to activate any spooks. Judging by the cardboard construction it’s likely they will fail after multiple uses, but you can switch one out quickly requiring only two hookup wires and a bit of tape.

Hopefully we aren’t stealing [Rich’s] thunder by recommending using Xbee wireless remote sensors to covertly monitor guests or trigger spooktacular scares.

We will be keeping an eye out for [Rich's] follow-up Halloween hacks. Join us after the break to watch the tutorial video on making homemade pressure plates.

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