movementshape

Movementshape is a descriptive term used in biomechanics, animation, and robotics to refer to the geometric shape of a moving object's trajectory in space over time, together with its timing and velocity profile. It is not a single formal theory but a shorthand for analyzing how motion is organized and expressed.

Key characteristics include the spatial path traced in three-dimensional space, the temporal profile of speed and acceleration, and non-motion elements such as pauses. Analysts often normalize time, compute curvature along the path, and extract shape descriptors such as path length, smoothness, or Fourier descriptors to summarize movement shape.

Data for movementshape analysis come from motion capture, inertial sensors, or video-based tracking. Methods include trajectory fitting, curvature and torsion analysis, principal component analysis on shape sequences, Fourier descriptors, dynamic time warping for motion comparison, and machine learning classifiers that distinguish different movement shapes.

Applications span biomechanics (gait, reaching, and manipulation), animation and gaming (defining motion style), robotics (motion planning and imitation learning), and sports science or rehabilitation (quantifying performance and recovery by movement shape).

The term movementshape is not yet standardized and may be used interchangeably with trajectory shape or motion shape in different disciplines.

See also: Kinematics, Trajectory planning, Motion capture, Gesture recognition, Shape analysis.