Meet the QRS 1: a quiet rail system with a modular track that works well with PTZ cameras and a MRMC robotic head. It comes with a variety of motion options, so you can use it on the floor or ceiling. You have the option to add or remove sections of the track from 1 to 20 meters.
The QRS 1 has max payload capacity of 44lb. It has max speed of 16 in/s. The above video shows it in action. More information is available here.