Response of A Magnetorheologi cal Brake under Inertial Loads

Abstract

Abstract:The study is objected to investigate the response of a magnetorheological brake (MRB) system under thefree move inertial mass. The disk-type MRB comprises of a rotating disk immersed in magnetorheological fluids (MRFs) and surrounded by an electromagnet coil. The magnetized coil causes a solidification of the MR fluid so that the shear stress between the moving part and static part increases resulting in the decrement speed of the moving parts. The shear stress can be varied by applying different electric current to the coil. The study began with the part design using the3D modeling software, followingbythe magnetostatic analysis. The flux density across the magnetorheological fluid could be predicted through this finite element magnetic simulation. The quantity of magnetic flux was then used to predict the shear stress between static and moving parts. The fabricated MRB was integrated onto a test rig which employs load cell and speed sensor as well as completely instrumented with data acquisition.Since the MRB test rig performed a simple free rotation system, a linear second order differential equation was derived to model the stopping time and braking torque behaviors. The equation of motion was built in a Simulink model, and the simulation results were compared to the real measurement. The achievable braking torque was also presented based on theaverage value from the load cell.

Improving Passive Ankle Foot Orthosis System Using Estimated Ankle Velocity Reference

“…The prototype structure was made by modifying a commercial Air Ankle Boot produced by China OEM, which initially had an articulated ankle joint and adjustable ankle ROM (maximum -45 to 45 degree). An MR brake at the ankle joint generates controllable damping stiffness [23], [24]. The MR brake is a T-shape brake [25], where the gap is filled with MR fluid LORD-132DG.…”

The Rheological Studies on Poly(vinyl) Alcohol-Based Hydrogel Magnetorheological Plastomer

“…Magnetorheological (MR) materials consist of micron-sized magnetic particles embedded in a carrier matrix, where its rheological properties can be reversibly controlled by the application of the external magnetic field. The materials can be categorized into several groups depending on the type of carrying matrix such as MR fluids, MR elastomers, MR grease, and MR gels [ 1 , 2 , 3 , 4 ]. Recently, a new kind of MR material known as MR plastomer (MRP) has gained a great attention from researchers as it is believed to possess high stability and better MR performance [ 5 , 6 , 7 ].…”

Performance prediction of serpentine type compact magnetorheological brake prototype

“…Magnetorheological (MR) fluids have been widely used for smart damping devices such as MR damper, MR brake, MR engine mounting and MR haptic device [1]. The use of MR fluids in the braking system has been revolutionary changing mechanical brake to the brake-by-wire system in which it is less employing mechanical parts [2].…”