public void addChildShape(CollisionShape shape, Vector3f location) {
        Transform transA = new Transform(Converter.convert(new Matrix3f()));
        Converter.convert(location, transA.origin);
        children.add(new ChildCollisionShape(location.clone(), new Matrix3f(), shape));
        ((CompoundShape) cShape).addChildShape(transA, shape.getCShape());
    }
adds a child shape at the given local translation
@param shape the child shape to add
@param location the local location of the child shape
jme3-jbullet/src/main/java/com/jme3/bullet/collision/shapes/CompoundCollisionShape.java