Characterization and Testing of an Electrorheological Fluid Valve for Control of ERF Actuators

Abstract

Previous studies of electrorheological fluids (ERFs) were motivated by brake, clutch, damping, haptic and resistive applications, but never motivated towards developing an ERF based-hydraulic rotary actuator. One design to make such an actuator is to use ERF-based valves. To fully understand the performance of such an actuator, it is imperative to study ERF valves. For this reason, this paper presents a summary of design considerations for creating ERF-based actuators, an ERF-based valve design for an ERF actuator and a new experimental test-bed to obtain viscosity and yield characteristics of the ERF at flow rates as low as 0.049 L/min, an order of magnitude lower than industrial rheometers. The new test-bed successfully measured the dynamic viscosity of the ERF to be at 0.6 Pa-s for low flow rates and 0.2 Pa-s for higher flow rates. The presented valve design can successfully resist 1 MPa of fluid pressure, which is an operation mode higher than any haptic and damping applications in the literature. The experiments also shows that higher flow rates negatively affect the ERF's yield characteristics for the first time in a situation where the ERF valve completely blocks flow. When the flow rates are increased, the response time to a fully-closed valve increases, the effective yield capability of the ERF decreases and the conductivity of the ERF increases.

A Review on Parametric Dynamic Models of Magnetorheological Dampers and Their Characterization Methods

“…One of the areas in which their possible applications are more fruitful, regards the damping of the mechanical vibrations. In this field, different materials have been proposed: piezoelectric materials ( [1][2][3][4][5][6]), shape-memory alloys ( [7][8][9]), electro-rheological fluids ( [10]), magnetorheological (MR) fluids, etc. The magnetorheological fluids are composed of a suspension of magnetically responsive particulate matters in a liquid phase.…”

Modelling and testing of a hydrodynamic clutch filled with electrorheological fluid in varying degree

“…For U = 0, when ER fluid is a Newtonian liquid, head rise balance of friction losses is described in formula (Nguyen et al, 2015)…”

“…For U > 0, the pressure loss in ER fluid which is a Bingham fluid flowing in the canal located within the electrical field is in form (Choi et al, 2002; Nguyen et al, 2015; Sims et al, 1999)…”

Stretchable and conformable variable stiffness device through an electrorheological fluid

“…Most of the reported studies investigated the viscosity change of ERFs and the characteristic of damping variation was used to develop a variety of dampers, [26][27][28] clutches, 29,30 tactile sensors, 31,32 and valves. [33][34][35] A few other scholars have studied the stiffness-variation characteristics of an ERF. Wang et al proposed a boring system that can increase its rigidity with an increase in the electric field by encapsulating an ERF in its boring bar, which increases the stability during boring and improves the machining quality.…”