Flexo (2003) by Ted Larson and Bob Allen, CA, USA. Flexo is an early forerunner of the AMPbot.
"It was finally time to make a smaller, improved version of Bender that could do more things. One thing I learned from all my work was that bigger balancing robots are usually easier—since they move slower, the control system doesn’t need to be as exacting in making minor corrections. But making a really tiny balancing robot becomes harder and harder the smaller you go. In the TV show Futurama, Bender has a brother named Flexo. So it made sense to name the new robot after him.
Since I now had a PID algorithm good enough to do things like balance a robot with an offset load on top of it and drive up and down ramps, I could easily mount a moving, pan-tilt-camera rig to the top without any fear of the motion of the camera knocking the robot over. I used a color tracking camera tuned to track the color red, so that if you put a red object in front of the robot, it would try to move toward you. Once it got close enough, it would just stand there and stare at you. We took Flexo to the HomeBrew Robotics Club once he was working, and there was a kid there wearing a red sweatshirt the robot really took a liking to!
Bob thought we might be able to find some companies that might be interested in paying for our expertise in developing these kinds of balancing robots. We bought a booth at the first RoboNexus trade show held in San Jose in 2004. On the first day, we were standing in our booth with Flexo showing off his balancing act, and who should come down the aisle riding a Segway but Dean Kamen himself. He rode up, stopped for a moment, and said jokingly, “Wow! Look at that! I have never seen anything like that!”
On the second day, we met a bunch of enthusiastic engineers from Hasbro. They were looking for more interesting robotic toys they could add to their line, as well as some help with more advanced sensors in toy development. We were invited out to Hasbro corporate headquarters in Rhode Island to give a presentation to the engineering team about what we could do. Bob asked if we needed to prepare a formal presentation, but Hasbro told us to just show up and bring some robots. When we arrived, we were shuttled into an enormous conference room that looked like it could seat 100 people, and there were 20 people sitting in there waiting to hear the presentation that we didn’t have! We thought we’d completely blown it, but we just turned on the robots and Bob started talking. Soon, the crowd warmed up, got out of their seats, and started coming to look at the robots up close, and it all worked out after that. Bob and I started a robotics consultancy called OLogic in 2005 with Hasbro as our first customer." – Ted Larson, From HomeBrew to Hasbro How two friends hacked a balancing robot and wrote a toy story of their own.