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Another crazy project

Posted by qwindelzorf on October 16, 2010

I and a friend (RedPeasant) decided, that in honor of the upcoming Portal 2, we would build a real-life, full-size, working (non-lethal) version of the sentry turret seen in the game.  Portal inspired lots of folks to make crazy sutff, including numerous weighted companion cubes, but as far as we can tell, nobody else has built the turret yet.

So, this is what we are aiming to create:

Sentry Turret Render

So, we started by pulling the 3D model for the sentry from the game's assets, then converting it so that it could be opened up in Pro-Engineer.  It was at this point that we realized just how much trouble we had gotten ourselves into.  The turret in the game is impossible.  It contains self-colliding geometry. Basically, the two gun pods cannot possibly fuly retract as they would collide in the middle of the robot. So, a little bit of editng later, we have physically possible geometry.  From there, we split up the various component parts of the turret -- pods, body, legs. Those parts were then exported as STL files.  


Those files were then sliced into one inch thick pieces.  Those pieces were then cut out of blue construction foam using my 4x4 router table.  


The layers get glued together, then sanded, then painted.  The piede in the foreground is the stacked layers for 1/2 the body, the piece in the background is a gun pod that has been glued, sanded, and painted.  

Now, we just have to do the other half.