Our metal belt is flat and straight.
We also make it run straight by Edge Positioning Control system.
Sensors acknowkedge belt width edges. Its signal triggers an electric actuator or air cylinder and the position of the driven pelly axis is adjusted.
Let's look at its precision in this video.
Steel belt video: http://www.youtube.com/results?search_query=dymcooverseas&sm=12
DYMCO, LTD URL http://www.steelbelt.jp