Building our robot for Pi Wars has been great fun and has been a journey. We have heeded the advice of other robot builders by testing as often and as thoroughly as possible. The Ely Makers team have a fantastic team of testers and as an added bonus they are children. Unpredictable, thorough, harsh critics and always pushing things to the limits.
Our latest test was a full speed slam-bam into a wall. This test will quickly show you the current weakest point is and in this case we discovered that the perspex plastic of the chassis had cracked. The robot could still drive ok but it felt like it would be just a question of time until it would break completely. Also I wouldn’t feel great using the robot in the Pi Wars challenges with such a critical flaw.
So after spending some thought we have decided to rebuild the robot again and try to replace the perspex chassis for something more durable. This will be the fourth version of the robot chassis and since we are so close to the competition this will obviously be our last rebuild. This is of course a bit of a setback as we were supposed to spend this time developing the software for the autonomous challenges instead. It seems like the right thing to do though as hopefully we will end up with a more robust robot on the whole.
Since we don’t know much about shaping sheet metal to make robots our first stop was Mackay’s hardware shop in Cambridge. We came away with a bag containing the basic tools and some sheets of aluminium. The aluminium only cost a couple of pounds and the tools cost about £30.
Here is a photo of the robot before the rebuild – what a mess!! 🙂
The underbelly looks like it could be tidied up a bit too.. The motors are good though – 1280rpm at 6V – Nice!
Taking it all apart without trying to upset too much of the wiring. 50.000mAh NiMH battery – bring it on..!
The perspex sheet cracked just where the motors were attached to it.
Marking out the holes in the piece of cut aluminium. The sheet is about 1.5mm thick which seems a nice compromise between weight and rigidity.
Starting to put it all together…
And the final result…
Looks good – like an electronics sandwich!