Don't get me wrong, I love my 3D printers, lasers and CNC machines, but there comes a point where you need something a bit more robust.
When your robot is going into battle, only metal will do!
In terms of robot competitions, especially in younger brackets, you will usually see more Vex than Actobotics. I had to take into account my use case and availability, so I went with Acto but they are pretty similar and can even be connected in some cases.
For my builds I have used a fair amount of 15-15 (Openbeam) and 20-20. The convenience of these modular pieces is the pre-drilled and spaced holes, the only problem is they use imperial units for some bizarre reason!
You should post your competition videos on STEEMIT.
In fact, I'd be interested to see a time-lapse video of you actually building your robot.
Best of luck!
I also would like to see a build article. What processor and OS will you be using.
Lately I have been going with a Pi as the central brain, with arduino for actuator control/analog input. I like Python for rapid iteration, what the motors/servos do is simple :)
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