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Updated: Jul 3, 2026
06:21
Postural Organization of Gait Initiation for Biomechanical Analysis Using Force Platform Recordings
Published on: July 26, 2022
Instability-induced hierarchy in bipedal locomotion
Kunishige Ohgane1, Kei-Ichi Ueda
1National Center for Geriatrics and Gerontology, Obu, Aichi 474-8511, Japan. ohgane@nils.go.jp
Summary
Human locomotion flexibility arises from coordinating initial leg posture via walking velocity, a global variable. This "instability-induced hierarchy" governs movement near neutral states.
Area of Science:
- Biomechanics
- Robotics
- Control Theory
Background:
- Human locomotion exhibits remarkable adaptability to environmental changes, a property termed flexibility.
- Understanding the control mechanisms underlying this adaptability is crucial for bipedal locomotion research.
Purpose of the Study:
- To model bipedal locomotion and demonstrate how initial-state coordination yields flexibility.
- To investigate the role of global variables in controlling gait dynamics.
Main Methods:
- Developed a model of the bipedal locomotion system.
- Utilized numerical experiments to analyze system dynamics near neutral walking/falling states.
- Defined global variables as dominant unstable directions.
Main Results:
- Initial-state coordination using a global variable, walking velocity, can produce locomotion flexibility.
- Confirmed that walking velocity and leg posture are key initial states.
- Demonstrated that global variables govern other variables near neutral states, forming an "instability-induced hierarchy".
Conclusions:
- Flexibility in human locomotion can be achieved through coordination of initial states by global variables.
- The concept of an instability-induced hierarchy explains how global variables control locomotion dynamics.
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