Abstract: A technique to detect the curve shape in real-time is presented in this paper, and it mainly uses the principle that "the point's strain on the surface of a pliable rod is proportional to the curvature on this point."Several different points' curvature on the surface of this rod can be obtained by measuring the strain gauges and related circuit, and the curve shape can be reconstructed using the computer based on these discrete points' curvature.