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Updated: Aug 2, 2026
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An Objective and Child-friendly Assessment of Arm Function by Using a 3-D Sensor
Published on: February 12, 2018
Organization of arm movements. Motion is segmented
1Department of Physiology, University of Minnesota, Minneapolis 55455.
Neuroscience
|October 1, 1987
Summary
This study analyzes human arm movements, suggesting complex learned motions are made of smaller, planar segments. Wrist trajectories in these segments show minimal deviation from planar motion, even with abrupt plane changes.
Area of Science:
- Biomechanics
- Motor Control
- Human Movement Analysis
Background:
- Learned continuous movements, like drawing figures, are complex.
- Previous research identified rules for wrist motion in arbitrary planes.
Purpose of the Study:
- To test if existing rules for circular/elliptical wrist motion apply to arbitrary learned trajectories.
- To investigate the hypothesis that complex movements comprise unit segments.
Main Methods:
- Kinematic analysis of human arm trajectories.
- Examination of learned continuous movements in free space.
- Testing a hypothesis on the composition of complex movements.
Main Results:
- Results support the hypothesis that complex movements are composed of unit segments.
- Wrist trajectories showed minimal deviation from planar motion within each segment.
- The plane of motion could change abruptly between segments.
Conclusions:
- Complex human arm movements can be understood as sequences of simpler planar movements.
- This segment-based model provides a framework for analyzing learned motor skills.
- The findings have implications for understanding and potentially replicating human motor control.
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