PENSA D.I. Wire bender

The D.I. Wire Bender by PENSA llc is an arduino-controlled CNC machine that bends metal wire to produce 2D and 3D shapes - an interesting take on a 3D printer. The D.I. Wire Bender can read vector files, OBJ files, text commands, and coordinates.

This is one of very few low-cost machines I've seen that can do rapid prototyping in metal - and it is open source! The Google Code project page is here. You will need tougher motors if you want to use tougher materials than 1/8" aluminum wire/rod.



I find the D.I. Wire Bender exciting for the following reasons:

• Rapid Prototyping in Metal is typically expensive; this could be a lot cheaper.
• CNC Rapid Prototyping is even better, because it removes a few chances for human error
• If we can do this, we can make a CNC pipe bender - Which would open up doors for rapidly prototyping and manufacturing new vehicle designs. For example, a CNC pipe bender would make it easy for the MakerPlane team to print out structural components for future non-composite aircraft designs.

Project Falcon: Free Interactive Wind Tunnel Simulation Software

Project Falcon is wind tunnel simulation software brought to us as a free technology preview by Autodesk Labs. The goal of Project Falcon is to help designers intelligently consider the aerodynamic properties of their designs without first having to learn computational fluid dynamics (CFD). This could be a great thing for vehicle designers.

Windows is the only supported operating system, but the minimum hardware requirements look pretty achievable.

To me, the exciting features of Project Falcon are:

• Free to download; no Autodesk license required
• Broadly accessible user-interface (Probably less intimidating than Elmer for your first foray into Aerodynamic design)
• Easy installation (register with Autodesk, download the project falcon installer, run the installer, double click the icon, then open the STL file you want to check the aerodynamics for)
• Blog/forum support via Autodesk Labs
• Users develop an intuitive grasp of aerodynamic principals using Project Falcon's rapid visual feedback in response to design and parameter changes
• No specialized knowledge required to study the aerodynamic properties of your 3D designs

If anything could motivate me to mess around with Microsoft Windows, it's probably Project Falcon, owing to the 2nd and last bullets on the list.

Here is a brief video introduction to Project Falcon via Autodesk Labs.



One thing the Project Falcon overview page emphasizes is the high speed with which this software calculates and displays results. A prominent complaint in the wind power optimization research papers I've run across is that CFD is computationally expensive and time consuming. So is Project Falcon sacrificing quality for speed? Probably. But this Project Falcon Validation paper shows that Project Falcon at least calculated the the correct coefficients of drag for a sphere, a cube, a cone, and an odd polyhedron that looks like a brick with 3 corners cut off and something small sticking out the bottom. I can't help wondering if Project Falcon has potential as a tool for optimizing the shapes of home-use wind turbine airfoils.

In the Aero Challenge, Local Motors has invited members of its open source vehicle design community to to use Project Falcon to help create a more aerodynamic design for the next Peterbuilt big rig.

Interactive Intro to Aerodynamics/CFD by Local Motors

If you are interested in automotive design and looking to develop a better intuitive grasp of aerodynamics, today is your lucky day.

PeterBuilt is sponsoring a design competition for the next Big Rig via the Local Motors Forge, a place where interested members of the online open source community can go to work and play at vehicle design.

The Local Motors website is encouraging visitors to download Project Falcon, and use it to play around with edgy new Big Rig designs for the Peterbuilt design competition.  Project Falcon is a new and at least temporarily free piece of wind tunnel simulation software that allows for interactive investigation of the aerodynamic performance of designs, and is intended to be used early in the conceptual design phase. Project Falcon reads .STL files, so you have a lot of options for CAD software to model your ideas. The goal is to find a design that will look good and increase fuel economy by achieving greater aerodynamic optimization of the vehicle. The motivation?  10 Awards, and $15,000 in prizes.

The design submission period is June 5th - June 26th.

Here's the video via Local Motors:




Project Falcon may also be a great tool for those of you looking to get into Open Source Aircraft design.

Look out for a future post with more details on Project Falcon software.

Eureka CNC: A Microfactory for Airplane Parts, Among Other Things

Eureka CNC is a microfactory that uses a CNC hot wire foam cutter to produce specialty aircraft parts, among other things. According to the Eureka CNC website, the owner, Stephen James, has a (very impressive) day job in the USAF, a family to provide for, and an awesome mental problem called project ADD...and he has still managed to single-handedly produce a wide variety of useful and cost-effective products and build a few airplanes of his own.

Exciting features of Eureka CNC:

• The ability to rapidly and precisely turn a 3-D CAD file into a foam airfoil core ready for the next step in the airplane build project (covering it in fiberglass)
• Extreme versatility and efficiency: products include custom crown molding, race car fairings optimized for structure and Reynolds number, and (most exciting of all) wing cores for a wide variety of home-built composite aircraft including the Long-EZ, Cozy MK III, Cozy MK IV, Berkut, E-Racer, Quickie Q2/Q200 with LS1,
• Although building it did not sound easy, the Eureka CNC hot wire foam cutter does sound like it's based on technology that is well within the reach of the open source community
•  Now that there are open source aircraft design projects in the works (click here and scroll down for a list), we will probably soon see rapid prototyping processes like Eureka CNC's make new aircraft design ideas a reality in record time.
• This technology could be applied to designing, creating, and selling some awesome fiberglass kit car bodies

I would love to see a higher level of integration between the outputs from conceptual design and mesh creation software like this, computational fluid dynamics optimization codes like this, 3D geometry output files, and affordable CNC rapid prototyping technology like the Eureka CNC hot wire cutter. Anything to shrink the currently huge amount of time between having an aircraft design idea and seeing it in prototype...

On a side note, I am a happy customer of Eureka CNC. My husband and I bought wing cores from Eureka CNC for our airplane build project, the Cozy MK IV. The average build time for Cozy MK IV projects is around 3000 hours, which amounts to a year and a half of 40-hour work weeks. Today, we are in the neighborhood of 10% done. Stephen James' microfactory-built CNC wing cores saved us a big chunk of time by completing several steps of the build project for us, so maybe that figure is more like 12-15%.

Craftsmanspace.com is Loaded with Free Design Resources

Craftsmanspace.com is full of free projects and technical plans, free books, free software, free 3D models, free patterns in various file formats, and free lessons on how to use carpentry tools.

The sheer diversity of resources available there is somewhat staggering.

Here are some highlights from my exploration of craftsmanspace:

• More free books about aviation than I could read in 10 years, including this one about helicopter design.
• A book from NASA entitled Capturing Energy From the Wind on the craftsmanspace renewable energy books page
• Playground equipment plans
• A huge list of free 3D CAD software
• A free 3D model/2D profile of a cat shaped wall coat rack (scroll down after the jump) in STEP/DXF format
• A scroll saw pattern for a portrait of Nikola Tesla in .SVG, .EPS, .DWG, .JPG, .GIF and .PNG
• Lessons on using a sliding T-Bevel

Elmer: Open Source Finite Element Software

If you're into science or design engineering, you should probably check out Elmer. Among a host of other great applications, this free, Finland-born software can help you design airplanes, predict the temperature distribution of a heat exchanger, and do your quantum mechanics homework.

At its core, Elmer is an open source finite element solver of partial differential equations. Development of Elmer began in 1995 as a collaboration between Finnish universities, research institutes and private industry, and was primarily developed by Finland's CSC IT Center for Science. Elmer was released as open source in 2005. According to the Elmer FAQ page, Elmer has hundreds of regular users worldwide and thousands of Elmer test users annually.

Click here for a 3-minute video introduction to Elmer.

Elmer processes partial differential equations in a descrete form, and handles coupled systems, non-linearities, and time-dependencies. The Elmer GUI allows the user to either import meshes or create simple ones in a variety of file types, and generates output in .grd, .mesh, and .ep files. The source code of Elmer is written in Fortran 90, C, and C++, and is distributed under the GNU Public License (GPL). The Elmer source code is here on sourceforge.

Here is a 10-minute Elmer tutorial from Elmer's YouTube Channel.


Thank you, Finland. It appears that your song needs a new verse.

Open Source Aircraft Design Software from NASA

I hereby retract any complaints I may have recently made about paying taxes.

The heroes at NASA just gave us some open source aircraft design software called Open VSP (vehicle sketch pad). This open source software is designed to let the  user rapidly create high-fidelity parametric design/structural layout for conceptual aircraft designs, resulting in models that can be processed into formats suitable for engineering analysis. According to the wiki, it's been under development since the early 90's, and J. R. Gloudemans, P.C. Davis, and P.A. Gelhausen presented a publication on the development of VSP at the 34th Aerospace Sciences Meeting and Exhibit in January 1996.

I'm guessing VSP has come a long way since then.

This ten-minute video introduces some of the features of Open VSP, by building and analysing an SR-71 Blackbird-like model:



The above video was created by Bill Fredericks, and stolen from the Open VSP Video Tutorial Page, which also contains a handful of more in-depth video tutorial videos created by Ami Patel.

The Open VSP code repository is on GitHub. The Open VSP wiki is here, and the Open VSP google group is here.

If you want to get going with some open source aircraft design, click here to visit the Open VSP project website and download the software.

You can find lots of free resources for open source aircraft design on my aircraft design page.