🤖 Humanoid Push Recovery Lab: Capture Point Stepping, Ankle Strategy and Cost of Transport

A Blender-built generic humanoid walks on the 3-D linear inverted pendulum (w = sqrt(g/z_c)). Shove it from any side and watch the swing foot re-plan onto the capture point x + v/w, the zero-moment point shift inside the foot (ankle strategy), and the leg reach decide whether it recovers or falls. Tune step length, step time, width, COM height, gravity and mass; see live ZMP and capture-point plots, joint torques, energy per step and cost of transport, plus headless experiments checked against closed forms. Simplified point-mass model; illustrative numbers.