self preserving robot.

I built a robot.. ish. it is for a microprocessing design class. The idea behind it was for it to self preserve itself. We centered the thing around a JM Micro Mini. Uses a Coldfire 32 module you can find the specs, and a 'midterm module' we used the light sensor on the midterm module, to read into the A/D converter (it has only one, otherwise we would have use the temperature sensor too) We read it in as a 16bit value (overkill admittedly but hey! we have the space!) and set cutoff values. one pin activates at one level of brightness, the other at the other level of brightness. The idea was to have a fan kick on with the dimness, and an umbrella on the brightness. The umbrella failed. I was using a 12v pull down solenoid I picked up from mouser and the plan was to control it with a relay. BUT the best laid plans of Mice and Men 'oft go awry. the relay was bad, so the 12v side was always open. ( I prob could have thrown more resistance in there I suppose) Hindsight being what it is, the project box needs to be back before I can square away another relay. The THEORY is sound though... So I do have a video, but only with the yellow light being the umbrella. I'd like to do this on a larger scale using venician blinds and a stepper motor. The code was too easy, we used freescale's CodeWarrior to program it, it's pretty plug and play... select this, configure that, generate code, a little logic and bam! it was done. Really we used time interrupts to read the value of the light sensor and check it against set values. we got those values by simply writing the code to check it and then watched the output of the sensor on codewarrior. Cover up the sensor a little bit, and write down that value, cover it up a little more and write down that value. Once it checks those values, it reacts accordingly. it's simple... The rest of it, weeellllll.... I had a brass weight that I super-glued to the cocktail umbrella. to pull it back down when the lever relaxed. Then using craft wood I built the solenoid lever combination. all was good except... the relay. With the presentation in less than 24 hours, and me turning in most of the hardware after that... I concede. FORTUNATELY the projects that went already weren't complete either. but in my mind, it's still a FAIL.