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Optimization of Ground Contact Model of Ankleless Lower Exoskeleton Robot for Gait Simulation

보행 모의 실험을 위한 발목 없는 하지 외골격 로봇의 지면 접촉 모델 최적화

  • Received : 2023.06.29
  • Accepted : 2023.08.19
  • Published : 2023.11.30

Abstract

The purpose of this study is to optimize parameters of a contact model to obtain similar ground contact force of human walking. Dynamic walking simulation considering ground contact is performed to determine load specifications when developing walking assist robots. Large contact forces that are not observed in actual experimental data occur during the simulation at the initial contact (e.g., heel contact). The large contact force generates unrealistic large joint torques. A lower exoskeleton robot with no ankles is developed with the Matlab simscape and the nonlinear hyper volumetric contact model is applied. Parameters of the nonlinear hyper volumetric model were optimized using actual walking contact force data. As a result of optimization, it was possible to obtain a contact force pattern similar to actual walking by removing the large contact force generated during initial contact.

Keywords

References

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