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Purpose: For the drop-induced shock mitigation system with magnetorheological energy absorbers (MREAs), the time lag of MREA has a nonnegligible influence on the shock mitigation performance. This paper proposed a minimum transmitted load control method considering time lag (MTL-T) is proposed. Methods: First, the influence of a time lag on the shock mitigation performance is analyzed, and the relationship between the theoretical controllable force and the actual controllable force of the MREA with a time lag is given. Then, taking the controllable force of traditional MTL control method as the theoretical value and the "soft-landing" as the control target, the control algorithm of MTL-T control method is derived. Finally, the simulation is conducted for the shock mitigation system with variable parameters controlled by MTL-T, and the comparative performance of MTL-T control method and other methods is given. Results: The theoretical analysis shows that MTL-T control method can make the shock mitigation system with a time lag achieve the control target of "soft-landing". The advantages of MTL-T control method are shown by the comparative performance of the MTL-T control method and other methods. Conclusions: Once the parameters of the system and the impact intensity are obtained, the MTL-T can be determined. The adaptability of MTL-T control method is verified. Compared with other control method, the MTL-T has a small peak transmitted load while making full use of MREA. [ABSTRACT FROM AUTHOR]

This paper proposed a minimum transmitted load (MTL) control method for drop-induced shock isolation mounts (SIM) with magnetorheological energy absorbers (MREAs). MTL control method consists of two parts of maximum damping force (MDF) control and one part of constant acceleration (CA) control, which can make the payload stop after fully utilize MREA stroke (soft landing) with minimum transmitted load. The control algorithm of MTL control method is derived in a single-degree-of-freedom (SDOF) system. The relationship between the controllable velocity range of MTL control method and parameters of shock isolation mounts is also derived. An optimal control method selection criterion between Bingham number (BN) control method and MTL control method is developed. The performance of MTL control method and selection criterion are shown by applying to the SIM system with variable drop velocities and system parameters. Results shows that MTL control method has the minimum transmitted load and the selection criterion is feasible. [ABSTRACT FROM AUTHOR]