Ralph Hollis - Ballbots

Who would want to make a mobile robot that has only a single spherical wheel? Well, I did! My talk will trace the development of the first successful “ballbot,” beginning in 2004. Now, many ballbots have been built or studied by other groups around the world—nearly 200 technical papers have been published with “ballbot” (a term I coined) in the title or abstract. Basic principles of the ballbot will be briefly described, including several experimental forays exploring its utility in everyday human environments. We introduce balancing, station keeping, and navigation from place to place within a map using LIDAR or visual simultaneous localization and mapping (SLAM). The addition of arms to the ballbot body adds complication, but also increases the range of possible applications. For example, large payloads can be lifted and transported when the ballbot leans its body. I will briefly summarize our current whole-body planning and control efforts.

In a quest to simplify the ballbot’s mechanics, we invented a novel closed-loop spherical motor (SIM) that is controllable in torque, velocity, and position in arbitrary directions. The SIM was used to create “SIMbot,” a functioning mobile robot that has only a body and a ball.

Finally, I will introduce a new, smaller, cheaper ballbot, which we call “Shmoobot,” that we are working to replicate for use as a platform for research and education in motion planning, control, and human-robot interaction.