An Untethered Magnetic Microgripper for High-Throughput Micromanipulation

Microgripper is a small-miniaturized robotic device employed to maneuver sub-millimeter-sized particles or objects that are too small to be manipulated by human hands or conventional tools. The design and fabrication of the microgripper pose challenges due to the integration of actuation components into their structure. To address this challenge, the authors in this work presented a novel magnetic microgripper wherein the functions of the actuation components are executed by the two pairs of microgripper arms made up of magnetic material. A custom-made electromagnetic system consisting of eight coils is employed to externally control these arms, enabling precise execution of gripping up to a maximum of two microparticles per working cycle. By varying the magnetic field strength from 20 to 120 mT, a wide range of gripper-arms opening distance is achieved, spanning from 0.3 to 1.3 mm. Consequently, the microgripper is demonstrated to grip different sizes of microparticles ranging from 0.3 to 1.2 mm. As part of the motion control capabilities, the microgripper is demonstrated to orient and navigate across a 360-degree range within the microfluidic environment. The presented microgripper holds promise for manipulating a wide variety of microparticle sizes and shapes, offering potential for high-throughput applications.