Pi Wars Week -17: Grab bag


First order of business this week: take the light hunting code I'd written and make it decide whether it is looking at something bright enough to consider an illuminated tile and drive towards it, or it isn't in which case we turn on the spot looking for another target. This is easy to do when blinding the camera with a 1200 lumen torch in a dim room, but will still require some more subtlety for a realistic challenge setting. That will definitely be a case for a calibration utility, the exact approach depending on how the course is built.


After several 5-6 hour 3d prints, I have all of the major body panels printed out at full scale.


I discovered fairly quickly that trying to stick structural panels together on non-flat surfaces with an old dried out bottle of superglue doesn't work brilliantly, so they are epoxied together, "reinforced" with hot glue.
With a complete shell I should be able to lay out the remaining internal parts (including space for the new turbo mega 11.1V 3S batteries) and revise the wiring loom so it's not relying on an XT splitter recovered from a crashed homebuilt tricopter.

edge detect


While umm-ing and ahh-ing about how best to put together the 100x20, 100x40 and 100x60cm boxes for a mockup of the Escape Route challenge, I happened on the empty box of a 55" TV at a friends house, and "can I have this? It's for robots" is apparently a good enough excuse for "rescuing" other people's recycling. Three slices of the box, cut and taped into the right shape and reinforced with extra bits of box flap made the movable obstacles, and some 1x5 wood recycled from previous years' course mockups complete the perimeter of the course. Still to do: paint it black to make sure it's realistically confusing for my LIDAR distance sensors.


Bonus build tip: the ceiling in Hitchin Hackspace isn't 3m tall so having nowhere to store full-length course side pieces upright, I made some foldable walls which can fixed into rigid lengths with just three screws, or folded down and stacked out of the way.


Notably absent: a zombie-shooting gun turret, a barrel-manipulating grabber and the oft-promised flashy lights and sounds. Perhaps Santa will bring me some nice metal gear servos and a 3.3V-5V level shifter :)