3D Printed Hovercraft Takes Flight

Last time we checked in on [Ivan Miranda] he was putting a drill press on the Internet. Lately, he has been trying to 3D print a hovercraft with some success. He made four attempts before arriving at one that works fairly well, as you can see in the video below. We will warn you, though, the screwdriver cam is a bit disconcerting and we suggest waiting at least an hour after you eat to watch.

The starboard impeller broke midway through the test, although with a single impeller it was working pretty well. [Ivan] thinks he can print the impeller …read more http://pje.fyi/Q9sNd4

Paul Jacob Evans


Interfacing with a Digital Speedometer

After swapping the engine out in his scooter, [James Stanley] made an unfortunate discovery. The speedometer was digitally controlled, and while the original engine had a sensor which would generate pulses for it to interpret, his new engine didn’t. Learning that the original sensor would pull the signal wire to ground each time it detected a tooth of one of the spinning gears, [James] reasoned he needed to find a way to detect the scooter’s speed and create these pulses manually.

To find the scooter’s speed, he installed a magnet on the front wheel and a hall effect sensor on …read more http://pje.fyi/Q7bN2P

Paul Jacob Evans

Hacker Challenge: Sail the Atlantic

We found it incredible that — apparently — no one has sailed an autonomous sailboat across the Atlantic successfully. Compared to an electric craft, sail-powered platforms ought to reduce having to carry batteries or other fuel and enable long-duration missions. The problem, of course, is the sailing conditions in the Atlantic.

The challenge is the focus of the Microtranssat challenge which started in 2010. You can think of the challenge as a race, but not in the conventional sense. Participants can launch their 8 foot (or less) craft any time between July and December, and it doesn’t matter which direction …read more http://pje.fyi/Q3DtvV

Paul Jacob Evans

Your Drone Is Cool, But It’s No Jet Fighter

There are some communities with whom our happy band of hardware hackers share a lot in common, but with whom we don’t often associate. The more workshop-orientated end of the car modification or railway modeler scenes, for instance, or the model aircraft fraternity. Many of these communities exist more for the activity than for the making, some of them dabble with building kits, but among them are a hard core of people who create amazing projects from scratch.

Take [Igor Negoda], for example. Not content with building just any model aircraft, he’s built his own from scratch, to his own …read more http://pje.fyi/Q1H0gq

Paul Jacob Evans

Instrument Packed Pedal Keeps Track of Cyclist’s Power

Exactly how much work is required to pedal a bike? There are plenty of ways to measure the power generated by a cyclist, but a lot of them such as heavily instrumented bottom brackets and crank arms, can be far too expensive for casual use. But for $30 in parts you can build this power-measuring bike pedal. and find out just how hard you’re stoking.

Of course it’s not just the parts but knowing what to do with them, and [rabbitcreek] has put a lot of thought and engineering into this power pedal. The main business of measuring the force …read more http://pje.fyi/Py4C5X

Paul Jacob Evans

Electric Longboard with All-New Everything

We love [lolomolo]’s Open Source electric longboard project. Why? Because he completely re-engineered everything while working on the project all through college. He tackled each challenge, be it electronic or mechanical as it came, and ended up making everything himself.

The 48″ x 13″ deck is a rather unique construction utilizing carbon fiber and Baltic birch. In testing the deck, [lolomol] found the deflection was less than an inch with 500 lbs. on the other end. He modified the Caliber II trucks to add four 2250W Turnigy Aerodrive brushless outrunners driving the wheels with the help of belts. The motors …read more http://pje.fyi/Phbdb1

Paul Jacob Evans

Open Source Modular Rocket Avionics Package

Cambridge postgraduate student [Adam Greig] helped design a rocket avionics system consisting of a series of disc-shaped PCBs arranged in a stack. There’s a lot that went into the system and you can get a good look at it all through the flickr album.

Built with the help of Cambridge University Spaceflight, the Martlet is a 3-staging sounding rocket that lifts to 15km/50K feet on Cesaroni Pro98 engines. [Adam]’s control system uses several Arm Cortex M4s on various boards rather than having just one brain controlling everything.

Each disc is a module that plays a specific role in the system. …read more http://pje.fyi/PhTMQZ

Paul Jacob Evans