RC Aircraft Precision Balancer and Work Stand

This morning I whipped together a “precision aircraft balancer” (like the Great Planes “C.G. Machine”.)  I built it out of $5.57 worth of PVC pipe and connectors from Fleet Farm and it probably took me an hour at the most.

The Plan

Here is my concept drawing:

IMG_20130625_083257

Shopping List

Here you are looking at $5.57 worth of PVC parts purchased locally.  The one flaw in the original design is that no one locally sold those 3-way corner connectors.  Maybe they don’t even exist?  So I made an on the fly design change while I was shopping.  The new design uses …
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Python Airfoil Manipulation Library

For lack of a better title …

I am creating a set of python libraries for designing and modeling aircraft.  Rather than spend a couple months learning a complicated and expensive CAD tool, why not spend that time learning python?  It makes perfect sense to me. 🙂

Scripted modeling (versus interactive point and click modeling) is a different mind set, but the advantage is you can make a change to the script and rerun it and that change cascades through all the parts and drawings and layout sheets.  In a gui based CAD system if you need to change the …
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Resolution 3: Design Evolution to First Flight

Here is a photo blog showing the progress from initial rough prototype, to final design, to mold making, to test flying the first production aircraft:

Resolution 3: Design to First Flight

This is a project that was sponsored by NOAA to develop a fully marinized small UAS that could be deployed from a variety of small vessels, recovered in the water, and used for marine debris detection or wild life surveys.

The “Resolution 3” purpose built UAS airframe is just one of the really cool products to evolve out of this project.…
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Real-time UAS Simulation and Visualization

Real-time UAS Simulation and Visualization

In previous posts I’ve described the process of carefully modelling the basic geometry and mass properties of a UAS in YASim to provide a real time flight dynamics simulation of the aircraft in FlightGear.  I also described how we carefully modelled the blended body shape of our UAS using airfoil plots and spline curves.  These curves were then imported into MoI and used as the basis to generate a smooth, flowing, organic surface shape.  MoI is able to export the model as a 3d triangle mesh in a variety of formats including 3ds.

Model Cleanup


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3D Modelling with MoI

3D Modelling with MoI

MoI (Moment of Inspiration) is a really interesting 3d modelling tool.  There are two things that separate it from other tools in my view.

1. It has a very simple and intuitive interface.

2. It has powerful and intuitive primatives for drawing and manipulating curves and 3d surfaces. For example MoI allows you to define 2d (or even 3d) curves and then stretch a 3d curved surface between your curved lines–possibly with additional guide curves to control the shape.  Like with any tool, it takes a little thought, practice, and planning to break down the structure …
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Physics Modelling

Dynamics (Physics) Modelling and Flight Simulation

There are many great tools available to help engineers design and develop new aircraft and flight control systems.  One such tool is the flight simulator.  More specifically: an open source flight simulation such as FlightGear. Being open-source FlightGear is flexible and adaptable and can be used to solve or explore new scenarios that a proprietary software applications may never have anticipated.

FlightGear + YASim

Here I describe the process of modelling a flying wing in FlightGear using the built in “YASim” physics engine.

A brief word on yasim (wiki documentation): YASim …
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3D Modelling … with … Perl?!?

3D modeling with perl?!?  What the…?  Huh?!?

Are you insane?  Yes, but in a nice sort of way (I hope!) 🙂

Since I’ve already admitted to being insane, you won’t mind if I explain the back story that let up to my evil plot.  I work with a small high tech company (ATI out of Wasilla Alaska … and yes if you were wondering, but no I haven’t met her myself.)  Some of the things we do is develop a variety of UAS related technologies.  One project involves developing a marinized (water proof) UAS that can be launched from a …
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