Motion Analysis of Simple Walking Models Driven by Minimalistic Periodic Input

In dynamic bipedal walking, it is generally expected that simple and efficient control methods can generate stable limit cycle gaits. Therefore, we assume that well-designed periodic inputs can achieve excellent walking performance while maintaining stability without relying on feedback. This study compares two typical bipedal walker models, namely the rimless wheel(RW) and the biped, to validate this assumption. The results demonstrate that both models can successfully generate a stable limit cycle gait. By fine-tuning the control parameters, we confirmed that the bipedal model with swing legs exhibited a higher susceptibility to entrainment compared to the RW model. Our work demonstrates the existence of time-symmetric input reaching spatially asymmetric results in walking robots, which has important implications for understanding symmetry breaking in nature and the behavior of complex systems.