Path Planning and Control for Autonomous Navigation of Single and Multiple Magnetic Mobile Microrobots

In this paper, we have developed an approach for autonomous navigation of single and multiple microrobots under the influence of magnetic fields generated by electromagnetic coils. Our approach consists of three steps. First, we have developed a heuristics based planning algorithm for generating collision-free trajectories for the microrobots that are suitable to be executed by the available magnetic field. Second, we have modeled the dynamics of the microrobots to develop a controller for determining the forces that need to be generated for the navigation of the robots along the trajectories at a suitable control frequency. Finally, an optimization routine is developed to determine the input currents to the electromagnetic coils that can generate the required forces for the navigation of the robots at the controller frequency. We have validated our approach by simulating two electromagnetic coil systems. The first system has four electromagnetic coils designed for actuating a single microrobot. The second system has an array of sixty-four magnetic microcoils designed for generating local magnetic fields suitable for simultaneous independent actuation of multiple microrobots.