Whole-body balance stability regions for multi-level momentum and stepping strategies

A unified framework is established for general balance stability criteria of biped systems. The regions balanced and steppable states are partitions the center-of-mass (COM) state space that augmented systems tasks. Their boundaries set maximum allowable COM velocity perturbations, under which a specified contact can be maintained (balanced) or desired step made (steppable). Whole-body models with full-order dynamics system-specific kinematic actuation limits to quantify effects momenta stepping on system's interactions. generality respect tasks verified humanoid robot human walking standing. Validity implications computed demonstrated in sagittal plane through comparative analyses across strategies against existing (capturability zero-moment point), reduced-order models, simulations. Distinct characteristics experimental (overly balanced) versus humans (unbalanced but steppable) validated, principle analyzed. also provide inter/intra-region multi-level momentum balancing. partition-aware controller implemented monitor current selectively exploit stabilizing actions during simulated standing push recovery.