Microrobotics is an attractive area of research as small-scale robots have the potential to improve the precision and dexterity offered by minimally invasive surgeries. One example of such a tool is a pair of micro-surgical scissors that was developed for cutting of tumors or cancerous tissues present deep inside the body such as in the brain. This task is often deemed difficult or impossible with conventional robotic tools due to their size and dexterity. The scissors are designed with two magnets placed a specific distance apart to maximize deflection and generate cutting forces. However, remote actuation and size requirements of the micro-surgical scissors limits the force that can be generated to puncture the tissue. To address the limitation of small output forces, we use an evolutionary algorithm to further optimize the performance of the scissors. In this study, the design of the previously developed untethered micro-surgical scissors has been modified and their performance is enhanced by determining the optimal position of the magnets as well as the direction of each magnetic moment. The developed algorithm is successfully applied to a 4-magnet configuration which results in increased net torque. This improvement in net torque is directly translated into higher cutting forces. The new configuration generates a cutting force of 58 mN from 80 generations of the evolutionary algorithm which is a 1.65 times improvement from the original design. Furthermore, the developed algorithm has the advantage that it can be deployed with minor modifications to other microrobotic tools and systems, opening up new possibilities for various medical procedures and applications.

翻译：微机器人学是一个极具吸引力的研究领域，因为小型机器人有潜力提升微创手术的精度与灵巧性。此类工具的一个实例是为切除位于身体深处（如大脑中）的肿瘤或癌变组织而开发的一对显微手术剪。由于传统机器人工具的尺寸和灵巧性限制，此类任务常被认为困难甚至无法完成。该剪刀的设计采用两块以特定间距放置的磁铁，以最大化偏转并产生切割力。然而，显微手术剪的远程驱动和尺寸要求限制了其穿刺组织所能产生的力。为应对输出力较小这一局限，我们采用进化算法进一步优化剪刀性能。本研究对先前开发的无缆显微手术剪的设计进行了改进，并通过确定磁铁的最佳位置及各磁矩方向来提升其性能。所开发的算法成功应用于四磁铁配置，从而提高了净扭矩。净扭矩的改善直接转化为更高的切割力。经过进化算法80代优化，新配置产生了58 mN的切割力，相比原始设计提升了1.65倍。此外，所开发的算法具有可经少量修改即部署于其他微机器人工具与系统的优势，为各类医疗程序与应用开辟了新的可能性。