The general rule of thumb is to place most of the cameras at 1 - 1.5m height and one per each 4 at a greater height of 2 - 2.5m. However, for specific motions other setups may be more beneficial. For instance, when an actor is lying on the floor or crawling, you can improve tracking quality by placing more (like half) cameras higher, up to the ceiling level.
Anyway, the system is flexible and you can get decent results with any reasonable setup. Even when you cannot follow all recommendations due to limitations in space or room's geometry.
5 and More Cameras Configuration
You can set up 5 or more cameras in a full-circle or a half-circle configuration, depending on available space. You can improve accuracy by placing one or two cameras high over the ground (like 3 meters high).
Recommended configuration for 6-camera full-circle setup:
Four Camera Configuration
You can set up 4 cameras in a half-circle or a full-circle configuration, depending on available space. You can improve accuracy by placing one of the cameras high over the ground (like 3 meters high).
Recommended configuration for 4-camera setup in half circle:
Three Camera Configuration
Recommended configuration for 3-camera setup is a half-circle:
Virtual view of the same scene:
Install the cameras on tripods and connect cables.
Sony PlayStation Eye cameras do not have standard tripod mounting screw, so you will have to use some kind of ad hoc solution. The simplest approach is to fix the cameras to tripods using sticky tape.
When mixing active and passive USB cables, make sure cable connection order is correct (computer->active cable->passive cable->camera).
If you're using the PlayStation Eye camera, make sure you have the lens set to the wide setting.