Building Homebrew VTOL Rockets

No one can deny what SpaceX and Blue Origin are doing is a feat of technological wizardry. Building a rocket that takes off vertically, goes into space, and lands back on the pad is an astonishing technical achievement that is literally rocket science. However, both SpaceX and Blue Origin have a few things going for them. They have money, first of all. They’re building big rockets, so there’s a nice mass to thrust cube law efficiency bump. They’re using liquid fueled engines that can be throttled.

[Joe Barnard] isn’t working with the same constraints SpaceX and Blue Origin have. He’s still building a rocket that can take off and land vertically, but he’s doing it the hard way. He’s building VTOL model rockets. Most of the parts are 3D printed. And he’s using solid motors you can buy at a hobby shop. This is the hard way of doing things, and [Joe] is seeing some limited success with his designs.

While the rockets coming out of Barnard Propulsion Systems look like models of SpaceX’s test vehicles, there’s a lot more here than looks. [Joe] is using a thrust vectoring system — basically mounting the Estes motor in a gimbal attached to a pair of servos. This allows the rockets to fly straight up without fins or even the launch rod used to get the rocket up to speed in the first few millseconds of flight. This is active stabilization of a model rocket, with the inevitable comments of ITAR violations following soon afterward.

Taking off vertically is one thing, but [Joe] is also trying to land his rockets vertically. Each rocket he’s built has a second Estes motor used only for landing. During descent, the onboard microcontroller calculates the speed, altitude, and determines if it’s safe to attempt a vertical landing. If the second motor has sufficient impulse to make velocity and altitude equal zero at the same time, the landing legs deploy and the rocket hopefully makes a soft touchdown in the grass.

While [Joe] hasn’t quite managed to pull off a vertical takeoff and landing with black powder motors quite yet, he’s documenting and livestreaming all of his attempts. You can check out the latest one from a week ago below.

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Do your projects violate International Traffic in Arms Regulations?

From time to time we consider the ramifications of hacking prowess being used for evil purposes. Knowledge is a powerful thing, but alone it is not a dangerous thing. Malicious intent is what takes a clever project and turns it to a tragic end. Conscientious hackers realize this, and [George Hadley] is one of them. While working on a new project he wondered if there were guidelines as to what knowledge should and should not be shared. It turns out that the United States has a set of International Traffic in Arms Regulations that mention concepts we’ve seen in many projects. He wrote up an article which covers the major points of the ITAR.

The gist of it is that sharing certain knowledge, by posting it on the Internet or otherwise, can be considered arms trafficking. It’ll get you a not-so-friendly visit from government officials and quite possibly a sponsored stay in a secure facility. Information about DIY radar, communications jamming, spying devices, UAVs, and a few other concepts are prohibited from being shared. The one qualifying part of that restriction is that it only applies if the information is not publicly known.