A novel type of tunable magnetorheological dampers operated by permanent magnets

作者：Kim Wan Ho; Park Jhin Ha; Kaluvan Suresh; Lee Yang Sup; Choi Seung Bok

来源：Sensors and Actuators A: Physical , 2017, 255: 104-117.

DOI：10.1016/j.sna.2017.01.012

• Magnetorheological (MR) fluid
• MR damper
• Permanent magnet based MR (PMMR)
• damper
• Magnetization area
• Switching mechanism
• Cylinder shape

This work presents a novel type of a magnetorheological (MR) damper in which damping force is tuned by the permanent magnet (PM) instead of the electro-magnetic coil circuits typically used to drive MR damper. The permanent magnet based MR damper (PMMR damper in short) consists of the ferromagnetic housing cylinder and the moving piston. One unique design concept for PMMR damper is to choose a proper shape of the ferromagnetic housing cylinder which is directly related the magnitude of damping forces. To analyze damping force characteristics, in this work 4 different housing cylinder shapes; rhombus, sandglass, curve and triangle, are adopted and their damping forces are analyzed from both an analytical model and a finite element method (FEM). Subsequently, the triangular shape of the cylinder is chosen for an experimental verification of the proposed design concept. The prototype of PMMR is manufactured by considering the Bingham properties of MR fluid as well as the magnetic intensity of the PM. The damping forces with two different PM are measured and presented in the plots showing damping force versus piston displacement and piston velocity. It is demonstrated that damping force of the proposed PMMR damper can be tuned by the location of the PM attached to the moving piston or by the shape of the housing cylinder. In addition, a concept of the rotating mechanism to operate the proposed MR damper for bi-directional dynamic motion is presented with a simulation result.

• 出版日期2017-3-1