public void setDynamicSubtree(PhysicsLink rootLink,
            Vector3f uniformAcceleration) {
        verifyAddedToSpatial("change modes");

        if (rootLink == getTorsoLink()) {
            getTorsoLink().setDynamic(uniformAcceleration);
        } else if (rootLink instanceof BoneLink) {
            BoneLink boneLink = (BoneLink) rootLink;
            boneLink.setDynamic(uniformAcceleration);
        }

        PhysicsLink[] children = rootLink.listChildren();
        for (PhysicsLink child : children) {
            setDynamicSubtree(child, uniformAcceleration);
        }
    }
Immediately put the specified link and all its descendants into dynamic
mode. Note: recursive!
<p>
Allowed only when the control IS added to a spatial.

@param rootLink the root of the subtree to modify (not null)
@param uniformAcceleration the uniform acceleration vector (in
physics-space coordinates, not null, unaffected)
jme3-jbullet/src/main/java/com/jme3/bullet/animation/DynamicAnimControl.java