The fuzzy C-means and multiple neural networks were introduced into soft sensor model for anode-cathode-distance(ACD) because of the difficulty of online measuring ACD of aluminum reduction cells.Many samples were optimized by fuzzy C-means.The soft sensor model of ACD was obtained by training those samples using multiple neural networks.The determination of auxiliary variables and methods of acquiring them online were discussed.The online visual system of ACD for aluminum reduction cells was developed.The ...