Abstract: In this paper, the dynamics parameters of the science toy the “memory alloy engine” are analyzed quantitatively. Based on the bending principle of the elastomer, the physical model is built, and the effective rotational torque of the “memory alloy engine” is calculated. Based on the principle of the belt drive, the relationship between the angular velocity, the linear velocity, the power and the radius of the memory alloy wire, the radius of the driving wheel, the toggle angle and the inclination angle is obtained. It is shown that a certain effective torque is the first condition for the engine to rotate.