Category Archives: Mach 30 Projects

Yavin Thruster Sprint 1

Mach 30 has started to use agile methodologies to manage its engineering projects, and the first of those to use an agile approach is the Yavin cold gas thruster. This last week, we completed our first sprint, and we’re all very pleased with the results.

For anyone that might not yet know about the project, it’s to develop a test stand connected to a source of pressurized gas, such as an air compressor, where different designs for the thruster can be tested. One of the aims for the project though is to develop and test new tools for future Mach 30 projects, such as CadQuery and our new Mathematics Tool Kit (MTK), a piece of software to make it easier to compile documentation around science and math proofs and analyses. We’re not only working to further develop these tools, but putting together a tool-chain for future design efforts. How this tool-chain works for Yavin is that we’re using MTK and a Python library to document and calculate aspects of the thruster such as wall thickness and nozzle shape. We can then create models with the same library in CadQuery, and export the model to be 3D printed.

In the first sprint, we took on 3 main items. The first of these was an export control review of the project, which can be found under the project’s Wiki on Open Design Engine. Second was a structural analysis of the gas chamber before the nozzle. The team generated a number of artifacts for this, including a document created with MTK detailing the analysis, a python library to support it, and an initial model created using CadQuery. You can see pictures of the model below, but the coolest part is that we printed it!

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This is just a proof of concept model though (it’s huge, and not an ideal size at all!). There’s a lot more work to be done! We have to produce another (or add to the existing) library to do the actual thruster design, and a number of other tasks.   Some work to do to make it so that CadQuery supports all the functionality we’ll need for making a good performing nozzle, but we also have a number of tasks ahead focused around testing.

For transparency, there’s one more item we had planned on doing, and that was performing a test calibration on a volunteer’s 3D printer.  Doing so helps us to build up information about how to calibrate other printers for printing future Yavin thruster nozzles. We don’t just intend for Mach 30 to print these, we intend for all sorts of people to do so, so we’re trying to make it as easy as possible on our end to print one of these.

We feel we accomplished a great deal for our first sprint, and we’re all very proud. If you care to hear more about our first sprint, you can check out our sprint review and retrospective here.

Jones Boys’ Rocketry

As Open Source Spaceflight Hardware (OSSHW) developers, we love to see other people building, modifying, remixing, and using our designs. In fact, we believe that the “Prime Directive” of Open Hardware is that it must be reproducible. That’s why we got so excited when we were contacted through Open Design Engine by John and Christopher from Jones Boys’ Rocketry. Christopher was working on a rocketry project for school, and was attempting to get a copy of our Shepard Test Stand thrust measurement hardware working.

John and Christopher

John and Christopher in February of ’08

Having someone build your Open Hardware has another advantage – you find more bugs and design flaws. The more people build and use your hardware, the better it gets. Our work with Jones Boys on Open Design Engine was no exception. They found a couple of bugs in our software, and their work brought about some operational improvements that we had glossed over because we’re so used to the hardware.

Christopher Testing the Shepard Hardware

After about two weeks of back-and-forth work, John and Christopher were able to get a successful data capture with a live engine.

Jones Boys’ Test Firing

Christopher was able to collect and analyze data from various motor fuel grain configurations and assembled everything into his science fair project display.

Christopher’s Display

Christopher took his display to multiple science fairs, and did extremely well. He was in 9th grade when he competed, and in the regional ISEF Science Fair, took first place in physics for his group. After that he went on to win second place in the American Institute of Aeronautics and Astronautics fair, which included a $100 cash award and a 3 day workshop at Goddard (I’m very envious). He also got an honorable mention from the USAF Office of Scientific Research.

Christopher Explaining His Project at the Science Fair

Congratulations to Christopher for doing a great job, and thanks to him for using Mach 30 hardware. We’re always excited to work with people who want to build spaceflight related hardware without starting from scratch. If you’re interested in building a rocket motor test stand or satellite receiving ground station, please feel free to contact us. We’d love to talk with you.

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Testing for Catastrophic Capacitor Failure

Ground Sphere Mk2 PrototypeSometimes what would appear to be a great idea turns out to be not-so-great. I had a concept of bedding the Software Defined Radio (SDR) and pre-amplifier for the Ground Sphere Ground Station in Greatstuff foam to make it more resilient to shipping and other mishandling, similar to the way delicate equipment is shipped in a two piece conformal foam mold.

Jeremy Wright asked a very simple question that I had not considered… what would happen if something electronic fried? That’s not entirely true… I did think of that, and so I selected Greatstuff Fireblock. Then he asked “Did ya test it?” The simple answer is no, I had not.

The Front Range Open Source Hardware Symposium

Front Range Open Hardware Symposium FlyerAfter a successful “hail mary” push to get the satellite simulator working, software installed into the borrowed Windows 7 laptop, and testing the Ground Sphere Mk2 prototype, we left Walsenburg around 10am on Thursday, heading to Boulder for the Front Range Open Source Hardware Symposium.  Attending as presenters rather than just attendees, We got the opportunity to show folks what we think open hardware is all about.  Congressman Jared Polis was  there as well as some of the companies that do Open Source Hardware (OSHW), such as SparkFun and others.  This was too good of an opportunity to pass up showcasing Ground Sphere, the Cubesat ground station receiver that we’ve been working on for months as a collaboration between Southern Stars and Mach 30. (more…)

New Space 2013 Wrap Up

J. Simmons at New Space 2013

J. Simmons at New Space 2013

As I mentioned in my last post, Mach 30 had a booth at the New Space 2013 Exhibit Hall.  This was our first time as an exhibitor at a major space conference, and it was time and money well spent.  We got to share our open source mission, demo two of our hardware projects, and meet some really great people.

The display materials in the booth, prepared by our graphic design ninja and board member Rebekah McGrady, covered our mission, open source hardware, Open Design Engine, the Export Control Task Force, and our current open source spaceflight projects.  One of the big surprises for me was just how well people responded to our mission.  Just a few years ago we would routinely be greeted with blank stares when we explained our mission is to develop open source spaceflight hardware.  This week I saw only one blank stare.  And everyone else was so excited by open source spaceflight that I got more than one high five.

I think part of the change in attitude was due to the fact that we had hardware to show.  Our booth included demos of two of our projects:  the Shepard Test Stand and our first ground station prototype.  More than a few people stopped mid stride when they saw the hardware on the table.  Those were always the best conversations.  The feedback we heard from the attendees about our hardware projects was extremely valuable.  For Shepard the big lessons were we should stick with the Arduino for our data acquisition system (teachers in STEM environments are already learning about Arduinos) and there is much more interest in Shepard at the collegiate level than I realized was out there.   For the ground station the big lesson is just how much demand there is from individuals and educators for this version of the ground station.  It is so high, I already have a number of emails already from people asking for a link to the project website.

As is always the case when we attend conferences, I met a number of great people at New Space. First is Liz from the Space Frontier Foundation’s Teachers in Space program. They are running teacher workshops about spaceflight and raising money to send teachers on sub-orbital flights. It’s a great program and we are talking about how the Shepard Test Stand and other Mach 30 open source projects could be used in their workshops. Next is Reuben who I met over drinks Friday night thanks to an introduction by Ethan, a Mach 30 volunteer. Reuben has experience in fundraising and has been sharing links with me for the Revenue Generation Committee.

Ground Station Demo

Ground Station Demo

Finally, last but far from least, is Tim from Southern Stars.  Southern Stars KickStarted a cubesat last year, the SkyCube, and he brought the engineering model to the conference.  It did not take the two of us long to realize he had a satellite and I had a ground station, and that clearly we should see if they could talk to each other. Within an hour we were sending messages from the SkyCube engineering model on one end of the exhibit hall to the Mach 30 ground station at the other end. And then, as if that was not cool enough, we decided to use the two projects to run an impromptu demo during a panel Tim was on later in the afternoon. Check out the very excited celebration of the demo over on Google+.

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