Spring-loaded inverted pendulum goes through two contraction-extension cycles during the single stance phase of walking

摘要: Despite the overall complexity of legged locomotion, motion center mass (COM) itself is relatively simple, and can be qualitatively described by simple mechanical models. The spring-loaded inverted pendulum (SLIP) one such model, describes both COM ground reaction forces (GRFs) during running. Similarly, walking modeled two SLIP-like legs (double SLIP or DSLIP). However, DSLIP has many limitations unlikely to serve as a quantitative model for walking. As first step obtaining walking, we explored ability single stance phase across entire range speeds. We show that employed quantitatively except exceptions: first, it predicts larger horizontal GRFs than empirically observed. A new angular radial (ARSLIP), overcome this deficit. Second, even active elements, therefore locomotion would require elements. Surprisingly, leg spring undergoes contraction-extension-contraction-extension (CECE) walking; cycling partly responsible M-shaped produced CECE cycle also lengthens duration allowing travel passively longer time, decreases velocity redirection between beginning end step. combination ARSLIP along with mechanisms transition from next necessary describe