Abstract
This paper tries to make a 2D biped with active telescopic legs and passive hip joint walk over a step-floor. By choosing a suitable fixed actuation pattern, the biped can walk through small up and down steps of 4.5[mm] without any change of actuation. This indicates a range of mechanical convergence ability of passive walk. For a larger variation of the floor height, stroke increase and timing delay of telescopic leg actuation is introduced. Using these techniques, the trial manufactured human-sized biped can walk stably through up and down steps of 52.5[mm].
