In view of the working characteristics of the rotary flying shear machine,multi-body dynamic simulations and experiments were applied to improve the shear rate of flying shear machine.The simulation model of the flying shear was established based on multi-body dynamics and transient dynamics.The motion trajectory of the flying shear machine in the process of operation was obtained by simulation calculations,and the dynamic response of the whole machine at different speeds was analyzed.Then,vibration tests of the flying shear machine were carried out by using the electrical measurement method to verify the reliability of the simulation model.Finally,the S-shaped acceleration and deceleration curve theory was introduced to optimize the working curve.The results show that the amplitude of the flying shear machine is reduced by 40% by using the optimized working curve,greatly reducing impact;at the same time,the shearing cycle is shortened and the shearing rate is effectively improved,the shearing accuracy is ensured.