Magnetic micro-robots are used widely in a narrow space, such as internal inspections and desilting of slender pipelines, minimal- or non-invasive diagnoses and treatments of various human diseases in blood vessels, and micro-manipulations, micro-sensing fields. Magnetic micro-robots are usually driven by several electromagnetic coils. It is essential to understand the magnetic field and magnetic forces acting on micro-robots to drive the magnetic micro-robots more effectively. In this paper, the finite element method is applied to simulate the magnetic field generated by a coil assembly. Moreover, a three-dimensional magnetic force simulation is also performed to reveal the magnetic forces acting on a cylindrical magnetic micro-robot. Experimental measurements validate the simulated results. A Hall sensor is used to measure the magnetic field along the coil assembly's axial and radial direction. The micro-robot is glued to a connecting rod, fixing a force sensor to measure the magnetic forces acting on it. The measured results are in good accordance with the simulated ones, which prove the validity of the simulation. The results from this study show potential to provide a reference to magnetic micro-robot applications.
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