Kanoun, Laumond and Yoshida suggest using a model where “Two successive footprints are viewed as two virtual rigidbodies joined by two prismatic joints and one revolute joint around the vertical” (2010, p. 478).
The defined distance between the feet assists with balancing the ZMP within the support polygon. This approach also means that the location of every previous step can be stored in memory – allowing the biped to backtrack if necessary.
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| Figure 1: Foot step locations with separation determined by two prismatic and a revolute joint (Kanoun, Laumond and Yoshida, 2010, p. 478) |
References
Kanoun, O., Laumond, J. and Yoshida, E. (2010). Planning foot placements for a humanoid robot: A problem of inverse kinematics. The International Journal of Robotics Research, [online] 30(4), pp.476-485. Available at: https://staff.aist.go.jp/e.yoshida/papers/ijrr2011-kanoun.pdf [Accessed 23 Jul. 2019].
Bilbiography
Kajita, S., Morisawa, M., Miura, K., Nakaoka, S., Harada, K., Kaneko, K., Kanehiro, F. and Yokoi, K. (2010). Biped Walking Stabilization Basedon Linear Inverted Pendulum Tracking. [online] pp.4489-4495. Available at: https://users.dimi.uniud.it/~antonio.dangelo/Robotica/2017/helper/bipedWalking_StabilizationLIP.pdf [Accessed 23 Jul. 2019].
