Non-Contact Cooperative Manipulation of Magnetic Microparticles Using Two Robotic Electromagnetic Needles

In this paper, we report a cooperative manipulation method for non-contact robotic electromagnetic needle manipulation system. We employ two 3 degrees of freedom (DOF) robotic electromagnetic needles to achieve an over-actuated manipulator, which can move the particle to any position in the planar workspace from any direction. The redundant DOFs, combined with an optimization-based control approach, enable the manipulator to achieve accurate path following and avoid the collision of needles. Using visual servoing, the developed controller can achieve line following accuracy of 0.33±0.32 μm, square following accuracy of 0.77±0.55 μm, and circle following accuracy of 0.89±0.66 μm with a 4.5 μm diameter superparamagnetic particle. The manipulator can also manipulate a particle along complex paths such as infinity symbol and letter symbols.