The machine adopts single-arm structure. The main machine is composed of column, upper beam, middle beam and workbench. The speed control system is installed in the lower part of the workbench. The servo motor with high speed regulation precision, wide range and stable performance drives the ball screw pair to rotate through the synchronous gear belt deceleration system. The ball screw pair drives the middle beam and drives the tensile attachment (or compression and bending attachment) to move up and down to realize the loading and unloading of the sample. The structure has the advantages of high stiffness, high efficiency and stable transmission.