Structural Design and Control of a Small-MRF Damper Under 50 N Soft-Landing Applications

To achieve less than 50 N soft-landing using magneto-rheological fluid (MRF) damper, a novel small-MRF damper has been developed. First, we design a new outer electromagnetic coil comparing with traditional inner coil structure, which can obtain miniature damper easily and control the magnetic field conveniently. Second, we apply silicon steel rather than carbon steel for MRF damper, which can improve the performance of response and demagnetization of the damper. The effectiveness of the innovative design is confirmed by experiments in this paper. The range of soft-landing load can be controlled from 18 to 55 N by adjusting the coil current from 0 to 0.8 A. Additionally, an impact force at the beginning can be eliminated using a modeled synchronous linear current, which indicates that the small-MRF damper has good soft-landing performance. Furthermore, the novel approach provides developing ideas for the miniaturization of the MRF damper.