Trinket uses RF to track you through the house

If you carry a cell phone with GPS, you always know where you are on the planet. But what about inside buildings or even your own home? Knowing if you’re in the kitchen or the living room would be a great feature for home automation systems. Lights could come on as you enter the room and your music could follow you on the home audio system. This is exactly the what [Eric] is working on with his Radiolocation using a Pocket Size Transceiver project. [Eric] started this project as an entry in the Trinket Everyday Carry Contest. He didn’t make the top 3, but was one of the fierce competitors who made the competition very hard to judge!

The heart of the project is determining Time Of Flight (TOF) for a radio signal. Since radio waves move at the speed of light, this is no small feat for an Arduino based design! [Eric] isn’t re-inventing the wheel though – he’s basing his design on several research papers, which he’s linked to his project description. Time of flight calculations get easier to handle when calculating round trip times rather than one way. To handle this, one or more base stations send out pings, which are received and returned by small transponders worn by a user. By averaging over many round trip transmissions, a distance estimation can be calculated.

[Eric] used a Pro Trinket as his mobile transponder, while an Arduino Micro with it’s 16 bit counter acted as the base station. For RF, he used the popular  Nordic nRF24L01+ 2.4 GHz transceiver modules. Even with this simple hardware, he’s achieved great results. So far he can display distance between base and transponder on a graph. Not bad for a DIY transponder so small if fits in a 2xAAA battery case! [Eric’s] next task is working through multipath issues, and testing out multiple base stations.

Click past the break to see [Eric’s] project in action!

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Make Awesome, Win Smoothieboard

If you haven’t looked around the RepRap project in a while, you probably haven’t heard about the Smoothieboard. It’s an extremely unique electronics board for 3D printers, laser cutters, and CNC machines that is trying to get away from Atmel and AVR microcontrollers and towards more powerful ARM micros. On the Smoothieboard, you’ll find enough five motor drivers, six big ‘ol MOSFETs for hot ends, fans, and beds, enough thermistor inputs for just about anything, and an Ethernet jack, because all 3D printers should be able to run headless.

The team behind the Smoothieboard has decided there’s not enough awesome included in the Smoothieboard already. To fix this, they’re opening up a contest where coders, documentarians, graphic artists, and creatives of all types can contribute to the Smoothieboard project. What’s the prize? A Smoothieboard, duh.

The Smoothieboard team is looking for a few good coders, builders, or anyone else to contribute to the Smoothieboard project. If you have an idea that would work with the Smoothieboard – a web interface like Octoprint running on the Smoothieboard, better documentation, graphics, or just want to build a five-axis CNC mill, this is where you sign up. The prize is a Smoothieboard 5XC, the top of the line board with five motor drivers.

Of course you’re always welcome to not contribute to open source projects, and for those consummate consumers, we have the Smoothieboard 5XC available in the Hackaday Store.

You have until February 15th to come up with a great project idea for a Smoothieboard. The best 30 project ideas will be chosen, and those projects will get a Smoothieboard. Actually building a project in a month isn’t a condition of the contest; the best idea wins.

Global Space Balloon Challenge

Looking for a reason to put up a balloon and payload into near-space? Not that one’s necessary, but the Global Space Balloon Challenge has got a variety of good reasons for you to do so, in the form of prizes and swag from their sponsors. Go for highest altitude, best photograph, longest ground track, best on-board science payload, or a bunch more. Have a look through the gallery to check out last year’s winners, including teams that dropped a 3ft paper airplane or floated an R2D2 replica.

Basically all you need to do is register on their website and then go fly a high-altitude balloon between April 10th and 27th. Last year 60 teams took part, and this year they’ve already got 90 teams from 31 countries.

And if you’re just getting into the (hobby? sport?) of high-altitude ballooning, be sure to check out their tutorials and forum. Of course Hackaday has been covering folks’ near-space balloon efforts for a while now too, so you’ve got plenty of reading.

So what are you waiting for? Helium’s not getting any cheaper and spring is on its way. Start planning your balloon launch now.

Trinket EDC Contest Winners

It’s time to announce the winners of the Trinket Everyday Carry Contest! We’ve had a great 5 weeks watching the projects come together. A team of Hackaday staffers spent their weekend watching videos and selecting their top entries based on the contest rules. We had a really hard time picking the top three – the competition was tight, and there were quite a few awesome projects.

Without further ado, here are the winners!

1337toolFirst Prize: 1337 3310 tool. [Mastro Gippo] really knocked this one out of the park. He built a swiss army knife of a tool out of the iconic Nokia 3310 candybar phone. 1337 3310 tool is a graphing voltage and current meter, an ohmmeter, a continuity tester that plays the original Nokia ringtone, and a gaming machine which can play Tetris.  [Mastro Gippo] is 99% there with TV-B-Gone functionality as well. Amazingly, [Mastro Gippo] kept the Nokia look and feel in his user interface. He spent quite a bit of time grabbing data and bitmaps from the 3310’s original ROM.  [Mastro Gippo] is getting a Rigol DS1054Z scope to help iron out the bugs in his future projects!

pavaproSecond Prize: Pavapro – portable AVR programmer. [Jaromir] built an incredible pocket-sized microcontroller programming tool. Pavapro can read and edit text files, handle serial I/O at 9600 baud, and burn AVR microcontrollers. If that’s not enough, it can actually assemble AVR binaries from source. That’s right, [Jaromir] managed to fit an entire assembler on the Pro Trinket’s ATmega328 processor. Pavapro’s 16 button keypad won’t allow for much in the way of touch typing, but it does get the job done with T9 style text entry. The device is also extensible, we’re hoping [Jaromir] adds a few other architectures! PIC and MSP430 modes would be awesome!  [Jaromir] will be receiving a Fluke 179 multimeter with a 6 piece industrial electronics tip kit! We’re sure he’ll put it to good use.

robohandThird Prize: Robotic 3rd Hand. Let’s face it. We can’t all be Tony Stark. But [Tim] gets us a little bit closer with his awesome wearable entry. Need a tool? Just press the button, and Robotic 3rd Hand will give you a … hand. [Tim’s] creation utilizes the Pro Trinket to drive a servo which moves an incredibly well designed and 3D printed mechanism that lifts a screwdriver off the wearer’s wrist and places it into their hand. [Tim] originally was going to go with Electromyography (EMG) sensors to drive the hand, however he switched to a simple button when they proved problematic. We absolutely think this was the right decision for the contest – it’s always better to have a simpler but working project rather than a complex yet unreliable one. That said, we’d love to see him circle back and give EMG another try! [Tim’s] next project will be soldered up with the help of a Hakko FX888D with a tip kit. If things get a bit wobbly, he can use his new Panavise 324 Electronic Work center to keep everything steady.

If you didn’t make the top three in this contest, don’t give up! We’re going to be having quite a few contests this year. The top 50 entrants will receive custom Hackaday EDC Contest T-shirts. Check out the full list of 50 on!

Trinket EDC Contest: USB Calipers

[Lou]’s entry for the Trinket EDC Contest is a great addition to the ubiquitous digital calipers found on workbenches and eBay resellers the world over. It translates the value displayed on the calipers to a USB HID interface for logging all those tricky measurements at the push of a button.

Most of the digital calipers you’ll find at Harbor Freight or on eBay are pretty much the same. There are two pads on the caliper’s PCB that give any microcontroller the ability to read what is being measured. It’s done with a 24-bit encoding scheme, where each bit is a nearly-BCD measurement in units of 1/1000 of an inch or 1/100 of a millimeter. After decoding the value, [Lou]’s trinket sends a few numbers to a computer over a USB HID interface.

Simply sending a measurement to a computer over USB wasn’t enough for [Lou]. He added three buttons to the project for typing multiple characters. The first button just sends Enter to the computer, the second sends a comma, and the third sends “/2 (Enter)”, exactly what you need to input the radius of something when measuring the diameter.

This was a project for the Trinket EDC Contest that ended a few hours ago. Nobody knows who the winner is, but there are some pretty cool prizes up for grabs including the new Rigol scope, a Fluke 179, and a soldering station.

Trinket EDC Contest – The Deadline Approaches

We’ve got just under 2 days left in the Trinket Everyday Carry Contest. With 79 entries, and t-shirts going to the top 50 entrants, you’ve got pretty darn good odds of getting a shirt out of all of this! The design is great too, [Joe Kim] really did a great job with it!



The idea is simple: Build small, pocketable projects which are useful everyday.

We explained everything in our announcement post, and the full rules are available on the contest page. But just as a reminder, the main requirements are

  • The project Must use a Pro Trinket, or a board based on the open source Pro Trinket design.
  • The project must have at least 3 project logs
  • The project must have at least one video
  • The project must include enough documentation to allow an average hobbyist to replicate the project

There are already some awesome entries vying for the top prize, but who knows – someone may come out of nowhere and walk away with a sweet Rigol ds1054z oscilloscope!


The contest deadline is January 3rd, at 12:00 am PDT. The clock is ticking, so stop waiting, and go build something awesome! Good luck to everyone who enters!


The final random drawing for Hackaday’s Trinket Everyday Carry Contest was held tonight, and the winner is [flaming_goat] with Trinket Pocket IR Analyser/Transmitter!

ir2In addition to having an awesome username, [flaming_goat] loves IR protocols. Trinket Pocket IR Analyser/Transmitter is a standalone device to read, analyze and transmit Infrared (IR) signals. The IR portion of the project is handled by a Vishay TSOP38238 (PDF link) The 382 series is a 3 pin module. It comes in several variants, each tuned to a specific carrier frequency. The 38238 will decode IR signals at 38 kHz.

The demodulated IR signals are fed into the Pro Trinket, where they can be analyzed. Data is either sent through the serial terminal or displayed on the on-board 1.44″ TFT LCD. Source code for the whole project is up on [flaming_goat’s] GitHub repo.

[flaming_goat] will be receiving a Teensy 3.1 and an Audio+SD adapter from The Hackaday Store. If the Pro Trinket is a gateway drug, then Teensy 3.1 is the hardcore stuff. Powered by a Freescale Kinetis ARM Cortex M4 processor in a tiny package, the Teensy 3.1 packs quite a punch. You might think all that power would mean complex tools, but Teensy 3.1 is still easy to program using the Arduino IDE. The Audio+SD adapter board gives Teensy 3.1 the ability to create some pretty decent audio, thanks to the Teensy Audio Library.

This was the last weekly drawing for the Trinket Everyday Carry Contest, but there is still time to enter and win the big prizes! The deadline is January 3 at 12am PDT. That’s just about 3 days to enter – so procrastinators, get in the game!