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Updated: Jun 19, 2026
09:13
A Vibrotactile Feedback Device for Seated Balance Assessment and Training
Published on: January 20, 2019
Balancing with vibration: a prelude for "drift and act" balance control
John G Milton1, Toru Ohira, Juan Luis Cabrera
1Joint Science Department, The Claremont Colleges, Claremont, California, United States of America. jmilton@jsd.claremont.edu
Plos One
|October 21, 2009
Summary
Adding vertical vibrations to fingertip stick balancing experiments doubled balancing time. This vibration reduced movement fluctuations, suggesting a new method to improve human balance control and reduce fall risk.
Area of Science:
- Biomechanics
- Human motor control
- Robotics
Background:
- Fingertip stick balancing is a key model for studying human balance control.
- Understanding the dynamics of balance is crucial for preventing falls.
Purpose of the Study:
- To investigate the effect of vertical fingertip vibrations on stick balancing performance.
- To explore the underlying control mechanisms and their implications for balance enhancement.
Main Methods:
- Subjects performed stick balancing on a platform inducing vertical vibrations (0.001 m, 15-50 Hz).
- High-speed, 3D motion capture analyzed fingertip and stick tip movements.
- Analysis focused on neural latency, speed changes, and horizontal plane position fluctuations (A(x,y)).
Main Results:
- Mean stick balancing time increased approximately two-fold with vibration.
- Vibration decreased the amplitude of horizontal position fluctuations (A(x,y)) without altering neural latency or speed distributions.
- A linear relationship was observed between vibration-induced skill increase and reduced position fluctuations.
Conclusions:
- Vertical fingertip vibration can significantly enhance stick balancing ability.
- Findings support a "drift and act" control model where vibration reduces oscillation amplitude.
- This suggests potential applications in designing footwear and surfaces to improve balance and minimize fall risk.
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