The research on the form and control method of impact load arresting buffer has been an active topic in the field of buffer arresting system(BAS).It becomes significant on reducing the weight of arresting system,improving the hindered efficiency,and guaranteeing the security of BAS.The hydraulic hindered device of impact load is currently used in BAS.There are some problems.For example,the system needs large power sources.However,once the power of active hydraulic control system is turned off,there arise unpredictable security risks.An arresting form of semi-active control based on magneto-rheological damper(MRD) is proposed,and the mechanical model of the BAS is established.Meanwhile,the state equation of impact load BAS is established according to the characteristics of impact load buffer arresting,and its sliding model buffer control is achieved.Due to the chattering characteristic of the output signal of sliding mode controller,the method to prevent chattering is designed based on short-term energy and zero-crossing rate detection.For the model and chattering suppression of sliding model buffer control algorithms,simulation results show that the proposed state equation and the arresting model are reasonable,and the design of semi-active control algorithm is effective.On the condition of the buffer control system requirement and the accuracy,the proposed algorithms effectively control the chattering of sliding mode control algorithms,and improve the security of the BAS. The research on the form and control method of impact load arresting buffer has been an active topic in the field of buffer arresting system (BAS) .It becomes significant on reducing the weight of arresting system, improving the hindered efficiency, and guaranteeing the security of BAS. The hydraulic hindered device of impact load is currently used in BAS. There are some problems. For example, the system needs large power sources. However, once the power of the active hydraulic control system is turned off, there aris unpredictable security risks. An arresting form of semi-active control based on magneto-rheological damper (MRD) is proposed, and the mechanical model of the BAS is established. Meanwhile, the state equation of impact load BAS is established according to the characteristics of impact load buffer arresting , and its sliding model buffer control is achieved. Due to the chattering characteristic of the output signal of sliding mode controller, the method to prevent chattering is designed based on short-term energy and zero-crossing rate detection. For the model and chattering suppression of sliding model buffer control algorithms, simulation results show that the proposed state equation and the arresting model are reasonable, and the design of semi-active control algorithm is effective .On the condition of the buffer control system requirement and the accuracy, the proposed algorithm effectively control the chattering of sliding mode control algorithms, and improve the security of the BAS.