public float centerOfMass(Vector3f storeLocation, Vector3f storeVelocity) {
        verifyReadyForDynamicMode("calculate the center of mass");

        recalculateCenter();
        if (storeLocation != null) {
            storeLocation.set(centerLocation);
        }
        if (storeVelocity != null) {
            storeVelocity.set(centerVelocity);
        }

        return ragdollMass;
    }
Calculate the ragdoll's total mass and center of mass.
<p>
Allowed only when the control IS added to a spatial.

@param storeLocation storage for the location of the center (in
physics-space coordinates, modified if not null)
@param storeVelocity storage for the velocity of the center (psu/second
in physics-space coordinates, modified if not null)
@return the total mass (&gt;0)
jme3-jbullet/src/main/java/com/jme3/bullet/animation/DynamicAnimControl.java