Electropermanent suspension system for acquiring large air-gaps to suspend loads

An electropermanent suspension system is presented in this paper which can suspend a load of 491 grammes at an air-gap of 61 mm with a current as little as 173 mA. The system comprises an electromagnet with high energy Neodymium-Iron-Boron magnets attached to the soft magnetic material core from both ends. Hall effect sensors are placed at the bottom of the electropermanent configuration which detect the magnetic field between the electropermanent magnet and the suspended load. The electronic circuitry of the sensors then ensure that the magnetic field is kept constant in the air-gap. The suspended load is also mounted with a high energy Neodymium-Iron-Boron magnet which adds to the already increased air-gap between the suspended load and the electropermanent magnet.