The arch structure of human foot absorbs impact and assists push-off movements during walking. The objective of this study is to introduce arch structures and toe joints into a biped robot, verify the effects, and devise walk control methods by dynamics simulation. We simulated the upright state and start of walking using Choreonoid. The results confirmed that the arch structure improved the impact absorption and stability in the anteroposterior direction. In addition, the arch structure could be expected to smooth the load transfer between the supporting legs during the step change.

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