|Mr X and Mr Hackenbacker|
Instead the brains of a PiWars robot has to be a Raspberry Pi, and in this case a Raspberry Pi 3A. Its combination of smaller size, whilst maintaining the power of its full sized brethren, makes it a go-to solution for many of the PiWars competitors.
Why not a shiny new Raspberry Pi 4 I hear you ask? Well for one a full sized Raspberry Pi takes up too much space in the cockpit, it would fit but then the battery wouldn't. Its also unlikely that any processing I need to do for the challenges would noticeably benefit from the increased performance, whereas the increased power draw, and heat produced, could have a detrimental affect on the robot. The additional i2c buses might be of use, but unless a 4A is suddenly announced I'll be sticking with the 3A.
|Too big on the left, fits on the right (Battery hidden out of sight)|
For the autonomous challenges the main inputs will be a Raspberry Pi camera, and a set of 4 VL53L1X Time of Flight (ToF) sensors positioned around Thunderbird 2. The camera, when combined with opencv, will be used to take pictures and perform either object, or more simply, colour recognition to aid in navigation. The ToF sensors, which work by firing lasers, will be used to detect how close Thunderbird 2 is to a wall or object.
|RPi Camera and ToF sensor|
The obvious output will be the motors that drive Thunderbird 2 around, with the less obvious being the gun for Zombie Apocalypse and, if I manage to get to it in time, a mechanism for capturing barrels in 'Eco Disaster'. I also hope to have an actual GUI this year that will be displayed on a wrist mounted Raspberry Pi (Fitting in with the newer 'Thunderbirds Are Go' way of remotely controlling one of the Thunderbirds).
Of course I'll be going into more detail on these items in future blog postings, unless I completely run out of time and abandon them!