Dynamic Modeling of Stick Slip Motion in an Untethered Magnetic Micro-Robot

This work presents the dynamic modeling of an untethered electromagnetically actuated magnetic micro-robot, and compares computer simulations to experimental results. The micro-robot, which is composed of neodymium-iron-boron with dimensions 250 μm x 130 μm x 100 μm, is actuated by a system of 5 macro-scale electromagnets. Periodic magnetic fields are created using two different control methods, which induce stick-slip motion in the micro-robot. The effects of model parameter variations on micro-robot velocity are explored and discussed. Micro-robot stick-slip motion is accurately captured in simulation. Velocity trends of the micro-robot on a silicon surface as a function of magnetic field oscillation frequency and magnetic field strength are also captured. Mismatch between simulation and reality is discussed.