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MODEL COG
This model-based item represents the Center of Gravity of the entire model. This center of gravity is calculated by first calculating the center of mass of each kinetic segment according to that segment's inertia. Visual3D provides default values for segment inertia, but these can be modified by the user to reflect any desired equation.
The center of mass of the model is then calculated as the center of mass across all of the model's kinetic segments according to mechanical principles patterns. Kinematic-only (or virtual) segments are not included in this calculation.
To express the MODEL COG item in the global coordinate system, choose the LAB segment as the resolution coordinate system.
Representativeness
The degree to which the center of mass of a model's segments agree with the center of mass of the participant being modelled will depend on how well the individual is represented.
For example, if the model includes only segments from the lower extremity then the center of mass of the segments will deviate substantially from the center of mass of the individual.