The Reliant Stadium retractable roof is moved by 20 transporters, each equipped with two traction wheels. The five transporters in each quadrant are connected onto a train by linkage suspension arms that are pinned at each end, and rotate vertically as needed to accommodate changes in the steel rails. The linkage suspension system evenly distributes roof weight throughout movement, and prevents any of the wheels from becoming high-centered or overloaded.
Also used at:
University of Phoenix Stadium
Lucas Oil Stadium