RoboGames 2007 – Alan Downing's Autonomous Robot Bear

There was more to RoboGames than the ear deafening noise and chaos of combat robots trying their utmost to disable or destroy each other - much, much more. Taking the opportunity to check out all the nooks and crannies of the Fort Mason facility we discovered lots of non-violent and simply delightful robots and their enthusiastic creators.


One of our personal favorites was the "PoohBearBot" - the work of Alan Downing, a manager at a large Silicon Valley software company, and an active member of the famous Home Brew Robotics Club. Alan was kind enough to spend some time explaining the robot to us, and patiently responding to our questions.

Lem: Have you been a robot fan all your life, or is this something more recent?

Alan: I've been interested in robots for as long as I remember, from toys to science fiction to building robots. Of my large collection of robot toys, the Tomy Omnibot, which still delivers candy at Halloween, is my favorite. 

Lem: Compared to many of the other robots here, your work seems to be very family oriented. Is this your own personal passion, or do some of the other family members get involved also?

Alan: The families of myself, my brother, and my sister have been doing a friendly 3-way combat robot competition for many years now. My family has a CO2 flip bot. The PoohBearBot, my project for RoboGames this year, was also family-inspired.

Lem: It's quite a contrast to the smashing battle robots over in the plexiglass shielded combat robot enclosure.

Alan: A lot of families with young children come to events like the Maker Faire and Robogames - and they're greeted by pretty scary robot visions like combat robots. I wanted to try designing and building a robot that is quieter and definitely more child safe and friendly.

Lem: Robotics development involves strong skills and know-how across a wide range of technologies. Where did you decide to focus most of your efforts?

Alan:  I'm most interested in autonomous robots. We wanted to make an autonomous robot aimed at younger children. A stuffed, jointed Gund Winnie the Pooh and a Vex served as the starting place, At the same time, one of my own personal  goals was to fill the bear with as many sensors as would fit - and I feel I was fairly successful. 

Lem: Could you give us a quick rundown of the robots performance specifications?

Alan: PoohBearBot has:

  • CMUCam2+ camera
  • 2.4GHz Wireless camera
  • 2 microphones
  • 2 force sensors (arms)
  • 3 capacitive sensors (arms, head)
  • 5 push switches (hands, toes, nose)
  • 2 dual axis accelerometers
  • 5 Hitec HB5995TG servos
  • 1 mini servo
  • 2 electromagnets on its paws
  • programmable "pooh knows your name" voicebox that sings songs like "row row row your boat" and "rumbly in my tumbly."
  • 7.2 volt battery packs (1 in each leg)
  • The software is written in C.

Lem: That's an impressive list of sensors and components. How much of it is already functional in the prototype?

Alan: The current PoohBearBot can sit straight, balance briefly while standing, walk (in a baby walker), crawl forward and back, and react to different sensory input.

Lem: What improvements are you working on?

Alan: The biggest current challenge I'm working on is to get both interesting behavior and the cmucam2+ working together within the Vex's 32K.

Lem: I noticed that you extended the 'robotization' way beyond just PoohBearBot.

Alan: Of course, PoohBearBot needs his own toddler push toy, so we added a Thomas-like Train with its own Lego RCX with Short Range IR, Long Range IR, 2 Multiplexers, 2 bumpers, 1 motion detector, 1 touch sensor, 1 ultrasonic sensor, and 1 motor. The train chooses which way to go as PoohBearBot slowly walks around pushing it.  He also has a car seat carrier and his own "car seat car" - which is a slightly modified Sharper Image "Targetbot."

Lem: Thanks for introducing us to PoohBearBot. We'll be very interested in watching how he develops between now and RoboGames 2008 next summer.

Alan: You're very welcome.


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