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Published on: April 13, 2016
Control strategy for stabilizing force with goal-equivalent joint torques is frequency-dependent during human
Jasper T Yen1, Young-Hui Chang
1Biomedical Engineering Program, Emory University/Georgia Institute of Technology, Atlanta, GA 30332 USA.
Summary
Human subjects coordinated leg joint torques to minimize ground force fluctuations during hopping. This coordination was key at slow frequencies, shifting to ankle torque reduction at high frequencies.
Area of Science:
- Biomechanics
- Human Locomotion
- Motor Control
Background:
- Human locomotion involves complex neuromechanical control.
- Understanding motor redundancy is crucial for stable movement.
- Hopping serves as a simplified model for studying locomotion control.
Purpose of the Study:
- Investigate how humans use motor redundancy in leg joints.
- Determine the coordination of joint torques to minimize ground force fluctuations.
- Analyze changes in control strategies across different hopping frequencies.
Main Methods:
- Subjects performed hopping at various frequencies.
- Joint torques and ground forces were measured.
- Analysis focused on torque coordination and force stabilization.
Main Results:
- Force stabilization performance remained consistent across frequencies.
- Joint torque coordination was vital for force stabilization at low hopping frequencies.
- At high frequencies, control shifted to independent joint variation, particularly ankle torque reduction.
Conclusions:
- Humans exploit motor redundancy to stabilize locomotion.
- Hopping frequency influences the underlying joint-level control strategies.
- Insights into motor control strategies for locomotion can be gained by studying joint-level variances.
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