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On the Estimation of the Center of Mass of an Autonomous Bipedal Robot

이족보행 로봇의 무게중심 실시간 추정에 관한 연구

  • 권상주 (한국항공대학교 항공우주기계공학부) ;
  • 오용환 (한국과학기술연구원 인지로봇연구센터)
  • Published : 2008.09.01

Abstract

In this paper, a closed-loop observer to extract the center of mass (CoM) of a bipedal robot is suggested. Comparing with the simple conversion method of just using joint angle measurements, it enables to get more reliable estimates by fusing both joint angle measurements and F/T sensor outputs at ankle joints. First, a nonlinear-type observer is constructed to estimate the flexible rotational motion of the biped in the extended Kalman filter framework. It adopts the flexible inverted pendulum model which is appropriate to address the flexible motion of bipeds, specifically in the single support phase. The predicted estimates of CoM in terms of the flexible motion observer are combined with measurements (that is, output of the CoM conversion equation with joint angles). Then, we have final CoM estimates depending on the weighting values which penalize the flexible motion model and the CoM conversion equation. Simulation results show the effectiveness of the proposed algorithm.

Keywords

References

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