Abstract:The longitudinal strip thickness error is an important problem in the hydraulic cold rolling industries, and the random disturbances may increase this error. To decrease this error, we proposed a new ARM9-based gauge control system, which is better than traditional automatic gauge control (AGC) system. This ARM9-based control system was comprised of an ARM9, three sensors, a fuzzy PI controller and other devices. The traditional AGC system was uncertain to deal with this error because the parameters were adjusted by human operators. This new ARM9-based control system had better chip such as ARM9 and used fuzzy controller to transform the uncertain information about this error into some certain data. Moreover, this new ARM9-based control system can be smaller and easier to carry. The experimental results were made with the Matlab tool, and the data show that this new ARM9-based gauge control system performs better than the traditional AGC system and is more robust than the traditional one against the distances.