Use a null object to group other objects. A null object doesn't have a shape, but it can be manipulated in 3D space.
Objects grouped under a null object are known as its children. They'll take on the properties of the null object. For example, if you change the scale of a null object, any children will change scale too.
To insert a null object:
When you select a null object in the Scene tab, you'll be able to see and make changes to its properties in the Inspector panel.
Uncheck this box to stop the null object and any children from being rendered in the scene.
Change the position, scale and rotation of the null object. You also use the manipulators to do this.
Insert simple combinations of patches involving the instance into the Patch Editor, like tap gestures.
Choose the camera or cameras on a mobile device in which you want to render the null object.