ElMo's Cannon Takes Shape

This weekend we put the electronics mostly to one side and concentrated on some mechanical engineering.  It was time to construct our cannon.  We already have a tris10 kickball kit and they provided a CAD file to 3D print a mount that it can sit in.  We spoke to the family design engineer (aka the lovely Uncle Tone) and he got in touch with his ever so helpful friend Tim - who just happens to own a 3D printer.  A massive, massive thank you to Tim from Team ElMo for helping us out.  He even provided an action shot of the mount being printed

We spent the afternoon cutting and drilling the perspex that the mount would be attached to

The kitchen table got a little bit messy - but we did tidy up afterwards

 We eventually came up with something that ought to do the trick quite nicely

Alas, a tiny miscalculation means that the upper piece does not caress the bowling ball as snugly as we were hoping (ok - its miles off) - we might add some foam pieces to bulk that out if it helps.  And the casters we ordered did not arrive in time to fix to the base - they finally arrived yesterday.  So we don't have a moving cannon - yet.  BUT - we did test it using a raspberry pi GPIO pin to control the discharge - and that doesn't appear to have any adverse effect on ElMo (huge sigh of relief there) - so hopefully we'll soon be able to attach our shiny green and purple appendage to ElMo and try it out in anger!

We're nearly done with the construction of ElMo now - we'd still like to try adding an OLED menu screen and some select buttons.  And  then there is quite a bit of coding to do.  But we're getting there - and having fun doing it :)