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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.
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Biased Electropermanent Magnetic Docking Design for Neutral Buoyancy UAV Deployment
This paper introduces a novel approach to enhance the docking mechanism of sensor packages deployed on bridges using unmanned aerial vehicles (UAVs). The current electropermanent magnet (EPM) system faces challenges in achieving efficient and stable docking due to factors such as airflow, GPS stabilization, and the time required for EPM activation. To address these issues, a biased EPM design is proposed, utilizing additional permanent magnets to achieve neutral buoyancy during UAV deployment. This design optimally balances the weight of the drone and sensor package, providing advantages such as improved stability against external factors and reduced pilot fatigue. Experimental results demonstrate the feasibility of the proposed design, indicating enhanced hold force and an extended range for efficient docking.
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- PAR ID:
- 10489196
- Publisher / Repository:
- American Institute of Aeronautics and Astronautics
- Date Published:
- Journal Name:
- AIAA SCITECH 2024 Forum.
- ISBN:
- 978-1-62410-711-5
- Format(s):
- Medium: X
- Location:
- Orlando, FL
- Sponsoring Org:
- National Science Foundation
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