Let's Make Robots!

CDR(Compact Disc Robot) UPDATE - Video

Explores via Ultrasound, Plays Zelda's Lullaby ( kinda ) when stuck

Hello LMRtians!  I finally got my bootloader code working.  I got my package in the mail from Sparkfun this morning.  I added a ball caster to the rear for better motion.  I used the bootloader to change the pins for the motors and speaker ( so I could use the bootloader ).  I adjusted the motor times for the new CD base.  I'm really happy with the turn times now.  I'm getting pretty close to 90 degree turns and 180 degree uturns.

I still need to add a reset button to the board.  I'm pretty unsatisfied with the delay in reading the ultrasound from the eyes.  CDR gets too close to blocks all too often.  I'm thinking of rewriting the whole thing and moving to the Sharp IR eyes.  

Nevertheless, I hope the video links OK.  I've been promising to do one for a while now.

Silly thing is, I'm more happy about the success of the bootloader than anything.  I reprogrammed the bot in circuit faster than my regular programmer!  in 733+, I'd guess I'd say \/\/()()+!

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Nice robot! Simple and practical. I have built a similar robot, but I had to add a second CD because the motors would come off too easy.

I don't understand why you complain about Ping measurements delays. According to the Datasheet, trigger time is 5us, the burst time is 200us, the return time after the burst can take up to 18.4ms and you need to wait 200us between measurements, so in total, you can get measurements very fast if there are close objects and up to 19ms if there are no objects. A Sharp IR sensor needs 39ms from the start of the measurement to the start of the next measurement for good results. 

However, walls or boxes at an angle to the Ping sensor can't be detected, because the sound is bounced away. I had to add bumper sensors to my robot to avoid crashing into wall. If you use the Sharp sensor, no bumper sensors will be needed, because the light is reflected in all directions.

If you want to see my robot (actually I should say my daughter's) take a look here: http://letsmakerobots.com/node/22467 and after I added the bumper sensors, see the video at the bottom of this page: http://letsmakerobots.com/node/22414