RoboSlave: Added Electronics to the Sumo Chassis

Last night was a busy night. From about 7pm to 2am I managed to do the following.

Design IR sensor bracket and standoffs
Fabricate the bracket and standoffs
Modify the ballast plate to mate with razor blade 'scoop'
Assembly everything to the chassis
Wire the line sensors on the bread board
Wire sensors to my makeshift sumo board (reusing my tachometer board)
Wire motor driver board to sumo board
Begin rough version of program
Fix all of my mistakes in wiring
and finally, actually get it moving in a somewhat logical fashion

The Cobra chassis does come with standoffs and additional hardware for mounting, but they were just a little too high for my taste. Using small diameter tube, I made my own standoffs which were about 1/4" shorter than the stock ones. My ultimate goal here is to limit the height in an attempt to reduce the IR signature (i.e. make it harder for other bots to see me). As you can see from the following images, it's quite low profile.

IR Sensors - Isometric View

Low Profile Front View

Side View

Although the Cobra kit came with the circuit diagram showing how to wire the line sensors, I wanted to make sure everything worked for me as it should. The included instructions are from Lets Make Robots. The image below shows the breadboard set-up The bottom left pin of the line sensor block is the output pin.

Line Sensor Circuit

The following images show the 'completed' sumo bot. I say 'completed' because this is only a rough first cut of the Bot. I plan on playing with the code to get this working well enough to figure out what improvements need to occur. For example, I can already tell (I think) that the IR sensors have too narrow of a field of view. This causes the bot to loose sight of it's opponent too easily. I'll try to include some video showing this on the next post.