Synchronicity: A Measure of Multi-Joint Movement Coordination in Device Assessment

Area of Science:

• Biomechanics
• Rehabilitation Engineering
• Human-Computer Interaction

Background:

• Smooth multi-joint movement is essential for healthy function.
• Deviations in movement coordination are associated with neurological conditions and injuries.
• Current assessments often rely on subjective expert evaluation.

Purpose of the Study:

• To develop an objective quantitative metric for movement coordination.
• To assess the synchronicity of joint movements during device use.
• To evaluate the potential of synchronicity as an indicator of device embodiment and rehabilitation effectiveness.

Main Methods:

• Utilized motion capture technology to record joint movements.
• Developed and applied a novel metric, synchronicity, to quantify movement coordination.
• Analyzed data from three studies involving wrist braces, transradial prostheses, and wrist exoskeletons.

Main Results:

• Synchronicity metric successfully characterized joint movements.
• The metric revealed differences in movement coordination across various populations and device conditions.
• Synchronicity showed potential as an indicator of how well devices are integrated and function.

Conclusions:

• Synchronicity offers an objective measure for evaluating movement coordination.
• This metric can aid in the development and assessment of assistive devices and rehabilitation strategies.
• Quantifying movement synchronicity may improve understanding of device embodiment and functional outcomes.