Building a Better Passive Walker

Brian A. McCann Abstract A passive dynamic walker is a mechanism which uses gravitational energy to walk down an incline with a periodic gait. Simple passive dynamic walkers have an inner and outer set of equal length legs which are pinned together at the hip. To prevent tripping, these walkers require alternating “stepping stones” for the feet to walk on top of. My senior design project involved building a passive dynamic walker which did not require stepping stones to walk down a slope. The walker was functional, but it could be improved significantly. For my RISE project, I was tasked with implementing these changes to build a better passive dynamic walker. I learned about the mathematic theory behind these walkers. I then used Matlab code developed by Professor Remy and computer aided design software to design a more optimized passive dynamic walker. Finally, I built the walker and implemented an Arduino control system to lift the inner legs. The project was a success. The final walker is larger, more durable, and walks with a periodic gait over a 0.5° to 6.0° range of slope angles.