The Rotational Viscometer is an intelligent instrument based on ARM technology, which realizes full touch screen operation, replacing the traditional operation method of buttons and small LCD screen. It uses high-performance stepper motors and drivers to operate accurately and smoothly according to program settings. The motor drives the spindle to rotate at a constant speed through the torque sensor. When the spindle encounters viscous resistance in the liquid being measured, the force is fed back to the torque sensor, and then through corresponding internal processing and calculations, the viscosity data of the liquid being measured can be displayed.