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Related Experiment Video

Updated: Jun 22, 2026

Experimental Methods to Study Human Postural Control
08:12

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Published on: September 11, 2019

Angular-velocity control approach for stance-control orthoses.

Edward D Lemaire1, Louis Goudreau, Terris Yakimovich

  • 1Institute for Rehabilitation Research and Development, Ottawa Hospital Rehabilitation Centre, Ottawa, ON, K1H 8M2, Canada. elemaire@ottawahospital.on.ca

IEEE Transactions on Neural Systems and Rehabilitation Engineering : a Publication of the IEEE Engineering in Medicine and Biology Society
|June 6, 2009
PubMed
Summary
This summary is machine-generated.

A novel hydraulic knee joint uses angular velocity to automatically control stance, enhancing safety for individuals with lower extremity weakness or recovering from knee trauma.

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Area of Science:

  • Biomedical Engineering
  • Rehabilitation Technology
  • Orthotics and Prosthetics

Background:

  • Traditional stance-control knee orthoses rely on external mechanisms for gait control.
  • These devices often require complex switching between stance and swing phases.
  • Existing systems may not adequately address sudden knee instability during ambulation.

Purpose of the Study:

  • To introduce a new angular-velocity-based control approach for stance-control knee orthoses.
  • To develop a hydraulic knee joint that automatically resists flexion upon detecting high angular velocity.
  • To eliminate the need for external control mechanisms for mode switching in knee orthoses.

Main Methods:

  • Development of a rotary-hydraulic device that resists knee flexion above a preset angular velocity threshold.
  • Testing the premise that angular velocity during knee collapse exceeds that during normal walking.
  • Functional testing of the hydraulic knee joint during simulated walking and instability events.

Main Results:

  • The hydraulic knee joint provided free motion during walking and engaged automatically during simulated knee collapse.
  • The device successfully supported body weight, aiding users in recovering a safe position.
  • The joint demonstrated durability, withstanding 200,000 loading cycles up to 88 Nm.

Conclusions:

  • The angular-velocity-activated hydraulic knee joint offers a promising, self-regulating solution for knee instability.
  • This technology has the potential to significantly improve safety and security for users with lower extremity weakness or joint trauma.
  • The device's passive engagement mechanism simplifies operation and enhances user confidence during ambulation.