Phys.org October 29, 2021
Time-varying magnetic fields generate eddy currents in conductive materials with resulting forces and torques due to the interaction of the eddy currents with the magnetic field. This phenomenon has previously been used to induce drag to reduce the motion of objects as they pass through a static field or to apply force on an object in a single direction using a dynamic field. A team of researchers in the US (University of Utah, Lawrence Livermore National Laboratory, industry) has shown that manipulation, with six degrees of freedom, of conductive objects is possible by using multiple rotating magnetic dipole fields. Using dimensional analysis, combined with multiphysics numerical simulations and experimental verification, they characterized the forces and torques generated on a conductive sphere in a rotating magnetic dipole field. With the resulting model, they performed dexterous manipulation in simulations and physical experiments. This method could stop a damaged satellite from wildly spinning so it can be repaired , something that would not have been possible before. It can also be used to manipulate objects that are especially fragile. The researchers believe that the principle of manipulating non-magnetic metallic objects with magnets could also have applications beyond the clearing of space debris…read more. TECHNICAL ARTICLEÂ
Induced forces and torques on a conductive sphere in three canonical positions relative to a rotating magnetic dipole. Credit: Nature volume 598, pages439–443 (2021)Â