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Title: A Compact Electropermanent Magnet Valve Geometry for Switching of Magnetorheological Fluid Using Particle Jamming
Electropermanent magnetic (EPM) valves consist of two permanent magnets, one with high coercivity and one with relatively low coercivity, which are able to rapidly redirect the flux within a magnetic circuit. When combined with magnetorheological (MR) fluid, they provide the ability to rapidly switch flow in a hydraulic circuit on or off. EPM valves contain no moving parts and draw no power except when changing state. These facts, along with their scalability, make them an attractive option for distributed flow control in small hydraulic systems. Current examples of EPM valves are often restricted to relatively low-pressure or low-flow operation. Miniaturization of small-scale hydraulic robots, both soft and rigid, is limited by the availability of sufficiently lightweight, compact, and efficient components which are capable of directing fluid at pressures greater than 700 kPa. This research proposes an EPM valve which leverages the magnetic properties of MR fluid to channel magnetic flux through the fluid. To evaluate the proposed geometry, an exploratory prototype was constructed and evaluated using a test-bench capable of evaluating the valve as a flow resistance. Simulations were conducted to evaluate the design and validate the use of simulation for future design iteration. To be of use in robotic systems, this valve needs to be capable of rapidly switching relatively high pressures while maintaining a highly compact and easily manufactured form factor. Due to its size and low power consumption, it is suitable for distributed hydraulic control in miniature systems such as hydraulically-actuated robots, including soft robots.  more » « less
Award ID(s):
1935278
PAR ID:
10586340
Author(s) / Creator(s):
; ;
Publisher / Repository:
In Fluid Power Systems Technology, vol. 88193, p. V001T01A024. American Society of Mechanical Engineers
Date Published:
ISBN:
978-0-7918-8819-3
Format(s):
Medium: X
Location:
Bath, United Kingdom
Sponsoring Org:
National Science Foundation
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