If you need a very thin, low power display that doesn’t use a whole bunch of pins on your microcontroller, [bobricius] has just the thing for you. His entry to the Hackaday Prize this year is a Charlieplexed LED display. With this board, you can drive 110 LEDs using only 11 GPIO pins.
Charlieplexing is a bit of a dark art around these parts. That’s not to say the theory is difficult; it’s really just sourcing or sinking current from a GPIO pin and arranging LEDs unparallel to each other. The theory is one thing, implementation is another. To build a Charlieplexed LED matrix, you need to go a bit crazy with the PCB layout, and god help you if you’re doing this point-to-point on a perf board.
Somehow, [bobricius] managed to fit 110 LEDs on a PCB, all while managing to break out those signal wires to a sensible set of pads on one side of the board. Only eleven pins are required to drive all these LEDs, making this project a great foundation for some very cool wearables or other projects that require a bright, low-res display.
Since [bobricius] can put 110 LEDs on a small board, he can obviously take LEDs away from that board. That’s what he did with his cut down version designed to be a clock. Both are great little boards, and the perfect solution for tiny displays for low-pin-count micros.
Barring the smallest manned airplanes, most aircraft that are pulled around by a prop have variable pitch propellers. The reason for this is simple efficiency. Internal combustion engines are most efficient at a specific RPM, and instead of giving the engine more gas to speed up, pilots can simply change the pitch of a propeller. With a gas powered engine, the mechanics and design of variable pitch propellers are well understood and haven’t really changed much in decades. Adding variable pitch props to something pulled around by an electric motor is another matter entirely. That’s what [Peter McCloud] is building for his entry to the Hackaday Prize, and it’s going into the coolest project imaginable.
This project is designed for a previous Hackaday Prize entry, and the only 2014 Hackaday Prize entry that hasn’t killed anyone yet.Goliath is a quadcopter powered by a lawnmower engine, and while it will hover in [Peter]’s test rig, he’s not getting the lift he expected and the control system needs work. There are two possible solutions to the problem of controlling the decapatron: an ingenious application of gimballed grid fins, or variable pitch rotors. [Peter] doesn’t know if either solution will work, so he’s working on both solutions in parallel.
[Peter]’s variable pitch rotor system is basically an electronic prop mount that connects directly to the driven shafts on his gas-powered quadcopter. To get power to the electronics, [Peter] is mounting permanent magnets to the quad’s frame, pulling power from coils in the rotor hub, and rectifying it to DC to drive the servos and electronics. Control of the props will be done wirelessly through an ESP32 microcontroller.
Variable pitch props are the standard for everything from puddle jumpers to acrobatic RC helis. In the quadcopter world, variable pitch props are at best a footnote. The MIT ACL lab has done something like this, but perhaps the best comparison to what [Peter] is doing is the incredible Stingray 500 quad. Flite Test did a great overview of this quad (YouTube), and it’s extremely similar to a future version of the Goliath. A big motor (in the Stingray’s case, a brushless motor) powers all the props via a belt, and the pitch of the props is controlled by four servos. The maneuverability of these variable pitch quads is unbelievable, but since the Goliath is so big and has so much mass, it’s doubtful [Peter] will be doing flips and rolls with his quads.
You can check out a video of [Peter]’s build below.
If you’re looking for a high entertainment value per byte of code, [Nardax] has you covered with his wearable spellcasting controller. With not much effort, he has built a very fun looking device, proving what we’ve always known: a little interaction can go a long way.
[Nardax] originally intended his glorified elbow-mount potentiometer to be a fireworks controller. Ironically, he’s now using it to throw virtual fireballs instead. Depending on the angle at which he holds his elbow before releasing it, he can cast different spells in the game World of Warcraft. We’re not at all sure that it helps his gameplay, but we’re absolutely sure that it’s more fun that simply mashing different keys.
There’s a lot of room for expansion here, but the question is how far you push it. Sometimes the simplest ideas are the best. It looks like [Nardax] is enjoying his product-testing research, though, so we’ll keep our eyes out for the next iterations of this project.
It’s a staple of home CNC construction, the 3D mill built on the bench from available parts. Be the on a tubular, plywood, or extruded aluminum frame, we’ve seen an astonishing array of mills of varying levels of capability.
The norm for such a mill is to have a computer controlling it. Give it a CAD file, perform the software magic, press button, receive finished object (Or so the theory goes). It’s a surprise then to see a mill in which the input doesn’t come from a CAD file, instead all control is done by hand through the medium of a joystick. [Mark Miller]’s 3D printed freeform carving machine is a joystick-controlled mill with a rotary tool on an arm facing a rotatable bed, and it can perform impressive feats of carving in expanded foam.
You might ask why on earth you should make a machine such as this one when you could simply pick up a rotary tool in your hand and start carving. And you’d be right, from that perspective there’s an air of glorious uselessness to the machine. But to take that view misses the point entirely, it’s a clever build and rather a neat idea. We notice he’s not put up the files yet for other people to have a go, if someone else fancies making CNC software work with it then we’re sure that would be possible.
There is a video showing the basic movements the mill is capable of, which we’ve put below the break. Best to say, though, it’s one on which to enable YouTube’s double speed option.
When I was asked to cover the Unconference in Los Angeles last week, I have to admit that I was a more than a little uncomfortable with the idea. I’m not big on traveling, and the idea of meeting a lot of folks was a little intimidating. Surely meeting Hackaday readers in person would be like walking into a real-life version of the comments section of a particularly controversial post. Right?
I couldn’t have been more wrong.
The LA Unconference, held at the Supplyframe Design Lab in Pasadena, was a far more collegial and engaging conference than any I’ve been to in my professional life. I couldn’t have asked for a better group to share the afternoon and evening with, and the quality of the talks was excellent. The Design Lab turned out to be a great space for the event — a large main room for the talks with plenty of little areas to break away for impromptu discussions and networking.
On Saturday the Hackaday community turned out in force to try something new. The first Hackaday Unconference was held in three places at the same time, and I was in Chicago and was amazed at the turnout and variety of presentations. The image above sums up the concept quite well, everyone shows up ready to give an eight minute talk, but as a whole, no one knows what to expect. Well, we should have known to expect awesome and that’s what we got.
As usual, people are excellent… to one another and in adapting to the fluid nature of the day. Pumping Station: One, a renowned Hackerspace in the Avondale neighborhood near downtown Chicago, opened their doors for us. Not knowing how many people to expect we set up two presentation rooms with a third on deck just in case it was needed.
We just barely squeezed everyone in one room for the first track but ended up splitting into two for part of the day. Here you can see that second room filling up. Even so we still had a handful of presentations that didn’t get a chance to shine — we simply must do this again so they can have the chance and because I had such a great time!
This is Hackaday’s global engineering initiative that encourages people to direct their skill and energy to make the world a better place. We call it the Hackaday Prize, but it’s far more than that. Join a community of talented people who enrich their own lives by seeking out new challenges and new technologies, then pioneers a way to combine them to Build Something that Matters. Show us your build by starting a Hackaday.io project page and enter today!
You Have Every Reason to Get Involved
The Hackaday Prize truly has something for everyone. Making the world a better place doesn’t end with a grand prize for a single build. Just by talking about your ideas and sharing your excitement you become the inspiration for this and every successive generation of problem solvers. But yes, there are prizes — a lot of prizes — and they’re spectacular.
We have over $250,000 in cash going out to hundreds of entries this year. The Grand Prize of $50,000 is joined once again this year by the Best Product Prize of $30,000. Four other entries will place second through fifth and receive $20k, $15k, $10k, and $5k respectively.
But the breadth of entries is too great to stop at that. We’ll select 120 projects as finalists and award each $1000. You can even get in on Seed Funding starting right away. We’re saving those details for the end of this announcement.
How Do I Build Something that Matters?
Whoa, all this talk of prizes, but you want to know what kind of hardware will be a hit for the Hackaday Prize? Here’s what you need to know: you can enter your project at any time from now until October 16th. But the exact time that you enter matters.
Your best bet is to get started right away. The first challenge of the Hackaday Prize is: Design Your Concept. Every great build starts with a plan and this is the time to show us what you got. The key is to consider if the project benefits society in some way. Show us how, document your build plan, and you can be one of the first twenty finalists to receive $1k cash and move on to compete for the big prizes.
We’ll have four more challenges that focus on different types of entries. You only need to enter one challenge, but you may choose to enter (and win) as many of the five challenges as you wish. We’ll be looking for connected devices that don’t suck Internet of Useful Things during the IuT ! IoT challenge. After that, it’s on to all things mobile with the Wheels, Wings, and Walkers challenge. Assistive Technology challenges you to make the world a better place for the physically or mentally challenged and aging or sick people of the world. And finally, a Hackaday favorite closes the challenge rounds with Anything Goes — as long as it clearly benefits society. Each of these five challenges will yield twenty finalists who receive $1000. That’s $100k!
The Return of Best Product
Two years ago we tried something new by adding the Best Product Prize to the mix and it was an enormous hit. We’re happy to be able to bring it back again this year.
There is a difficult path from a working prototype to a product ready for its audience. As hardware development is unlocked for an ever wider engineering community, we want to see the path made wider so that the journey becomes easier. Best Product is designed to do just that.
Any Hackaday Prize entry may also choose to compete and be named the Best Product (receiving much deserved recognition as well as the addition $30k prize). You need to submit your entry no later than July 24th, which includes full documentation of the project as well as a bill of materials used in the build. We’ll select twenty finalists (sending $1k to each) who will then need to deliver three working beta test units for the final judging round of the Best Product.
How Can We Pick the Top Entries?
One amazing part of the Hackaday Prize family are the world-renowned experts who donate their time and talent as Judges. They are just as eager as everyone else to see all of this creative energy focused on solving the problems facing our civilization.
When realized to their full potential, design concepts should knock the socks off of anyone who reads through them. Because of this we have one more thing in store for you during the first challenge which starts right now.
Entries with the most likes at the end of the first round will split $4,000. Each time someone on Hackaday.io “likes” your project it will move a bit higher on the leaderboard found on the Hackaday Prize page. The top projects will receive $1 for each like, with a max of $200 per entry so that at least twenty will win (but likely many more).
This seed funding is a little push to help offset the cost of building prototypes. But it really comes down to your decision to make the time and to make a difference. Enter your project in the Hackaday Prize now.
As usual, people are excellent… to one another and in adapting to the fluid nature of the day. 
We have over $250,000 in cash going out to hundreds of entries this year. The Grand Prize of $50,000 is joined once again this year by the Best Product Prize of $30,000. Four other entries will place second through fifth and receive $20k, $15k, $10k, and $5k respectively.
Your best bet is to get started right away. The first challenge of the Hackaday Prize is: Design Your Concept. Every great build starts with a plan and this is the time to show us what you got. The key is to consider if the project benefits society in some way. Show us how, document your build plan, and you can be one of the first twenty finalists to receive $1k cash and move on to compete for the big prizes.
