H.E.C.To.R (Home Experimental Computerized Toy Robot)
Hector was my school project- we each had to make and program something using the inputs and outputs of the MC68HC11 microcomputer at DeVry. I already had the gearmotors and wheels connect to the base before I took the class.
The motors were operated by 4 relays in a H-bridge configuration. I built that for my very first attempt at building robot, "Rodney" from David Heisermann's TAB book, "How to Build Your Own Self-Programming Robot". Unfortunately, it was too big for Hector, so I had to rip it up, unsolder things and put it back together on a smaller scale.
He was programmed in assembly and basically just avoided walls using Infra-red proximity detection circuits. He had bumper switches, but I don't think I ever connected them.
I was also able to use Hector for my final project. I wanted him to locate a candel and put it out, but the school wouldn't let me use a compressed CO2 canister, so we had balloons tied to it and it just approached a candel until a balloon popped.
Other team members were responsible for creating a "head" that would scan for UV light using a stepper motor and send the approximate location to my board and I would get it turn towards that zone using a homemade shaft encoder.
We got the damn thing working correctly for the first time the night before the projects were to be judged- and I couldn't test it for too long, because it took almost 2 days to charge up all the NiMH batteries with my 1 battery charger.
Anyway, he searched for a fire painfully slowly, and we came in 4th place, which I considered a miracle at the time.
Avoid obstacles
- Actuators / output devices: 2 dc 12V gearmotors
- Control method: autonomous (only)
- CPU: MC68HC11
- Power source: 12v nimh for motors, 9v nimh for logic
- Programming language: Assembly language
- Sensors / input devices: custom built infrared emitter/detectors
- Target environment: indoor