Design and experiment of multi-functional magnetorheological damper
A multi-functional magnetorheological (MR) damper with energy harvesting, velocity self-sensing and controlled damping force was designed, fabricated and tested. The energy harvesting and velocity self-sensing mechanism was composed of a permanent magnet array and induced coils which moved vertically. The proposed MR damper used the piston rod as the sharing component between the energy harvesting and velocity self-sensing mechanism and the MR damper part, and this shared component could isolate the magnetic field between two function areas. The mathematical model for the energy harvesting and self-sensing capability of the proposed MR damper was derived. Finite element model of the energy harvesting part was built up to address the power generating efficiency using ANSYS software. Experimental tests were carried out to address the performances of the proposed MR damper. The results showed that the damping force was ranged from 200 N at the current of 0 A to 750 N at the current of 0.6 A. The dynamic range equaled to about 3.75. The AC-DC rectifier was applied on the power generating, and the results showed that 1.0 V DC voltage output was harvested after the AC-DC processing. Meanwhile, the velocity self-sensing performance was experimentally evaluated under different excitation frequencies and amplitudes. The experimental results showed a well fit curve under different excitations. In other words, the efficiency and feasibility of the velocity self-sensing capability of the MR damper were proved.