Lateral bending manipulator automatic detecting and control method in medium and thick plate rolling process

The invention discloses a lateral bending manipulator automatic detecting and control method in a medium and thick plate rolling process. The lateral bending amount delta c of a rolled piece is calculated according to the opening degree of a manipulator and the width of the rolled piece of the corresponding pass; the lateral bending curvature radius R is deduced through the length of a manipulator guiding plate and the delta c in a combined mode; through mathematical modeling, the relation between the lateral bending curvature radius R and the thickness deviation delta h of the two sides of the rolled piece is resolved; and the roller gradient is made to be equal to half of the delta h, and then the roller gradient for eliminating lateral bending is solved. The method specifically comprises the following steps that whether the current pass belongs to the last six passes or not is judged; the opening degree m of the manipulator is read; the width b of the rolled piece is read; the delta c is calculated by subt