Design of a Dual-Layer Four Quadrants Orthogonal Microcoil Platform for Independent Control of Multiple Magnetic Microrobots

Compared to the limitations of relying solely on a global magnetic field response, utilizing local magnetic fields enables the independent control of multiple microrobots, regardless of variations in their size and orientation. In this letter, we develop a dual-layer orthogonal local magnetic field generation system, by dividing the workplace into four quadrants and setting transition microcoils between them. The designed system enables simultaneous motion of multiple microrobots, allowing for either cross-quadrant movement of a single microrobot or independent motion of multiple microrobots. This innovation is underpinned by the development and validation of a meticulously crafted microcoil model, which analyzes the impact of input currents and studies the magnetic field distribution within its workspace. Building upon this foundation, we propose an innovative actuation and drive strategy for microrobots utilizing the microcoil platform. Besides, a magnetic field analysis model is developed for microcoils under various activation states, confirming the effectiveness of the proposed drive strategy. Finally, we validate the microcoil driving system through our experimental platform, highlighting the robustness and efficiency of the new design. The experimental results demonstrate that this approach holds significant potential for micromanipulation tasks.