REG•E the Robot

This is REG•E and he is my first obstacle avoiding robot.

He works off two Lego motors powered by 4 AA batteries and for a brain he has an Arduino Duemilanove. He uses an ultrasonic range finder to 'see' what's in front of him. Motor control is thanks to the TIP120 transistor and this tutorial here:

As for where I go from here I am not sure. I would love REG•E to learn as he goes and adjust his behavior accordingly. I would also like him to collect and record data on his travels too - exactly what I am not certain yet.

This is my first posting on LMR and I hope it helps me continue to push my robot project forward instead of fizzling out like so many things that I start and give up on. Thank you for looking at REG•E, I would be grateful of any feedback and/or suggestions you may have.

If you would like to see the other things I make, here is a link to my tinkering section of my site:

Obstacle avoidance

  • CPU: Arduino Duemilanove
  • Power source: 4 AA batteries
  • Sensors / input devices: Ultra sonic range finder

This is a companion discussion topic for the original entry at

i like it !!

i like it !! it looks really cool and simple :) 

Thank you.

I think in my case starting simple is the best way to approach something. Although simple, I’ve already learnt a great deal.


why every time that there is object in front the robot it take 5 sec to turn?



I put in a pause deliberately (ok I think the pause is a little too long to be fair) as I found that if I didn’t get the robot to stop before turning, the momentum meant he didn’t turn as sharply.

I’m restricting the power to the motors at the moment so he’s not running at his fastest. When he is and I remove the pause, his turning circle is rather large. Putting in a pause and slowing him down a bit ensures he turns a more tightly.

Thanks for commenting.