Patent ID: 8863584

Claim:
A material testing system that performs testing on a test piece having an elastic region and a plastic region, the material testing system comprising: a pair of grippers that grips both ends of the test piece; a moving member that moves one gripper of the pair of grippers; a displacement meter that measures a displacement in a distance between gage marks on the test piece at a time when the one gripper is moved by the moving member; movement measuring means adapted to measure a movement of the moving member; computing means adapted to successively compute a change ratio R that is a ratio between the displacement in the distance, the displacement being measured by the displacement meter, and the movement of the moving member, the movement being measured by the movement measuring means; means adapted to, on a basis of the successively computed change ratio R, compute a parameter K used to perform feedback control of the movement of the moving member; and a feedback control part, wherein when the change ratio R exceeds a setting value, the feedback control part changes a value of the parameter K used for the feedback control to a value that makes an influence of the feedback control small, and performs the feedback control.