Why must I use SDK 3.1 to use the Sensor 3?
Structure Sensor 3 was redesigned from the ground up. It uses all new components, from its chassis, to its power system, to its cameras, and it uses a completely new chipset for processing camera data into usable depth maps.
As a consequence, we needed to create new software to communicate with the new Sensor, and the only way to distribute that software is through an update to our SDK.