Development of spirally coiling, force-sensing soft-robot for safe and accurate cochlear electrode implantation

人工耳蜗（CI）正迅速成为毛细胞相关性听力损伤患者的主要康复辅助工具。国家目前的人口统计表明，在可预见的未来，CI的采用将以更快的速度增长，这要求CI技术有更多的创新。尤其迫切的是需要安全、准确的CI电极阵列插入方案，由于其对插入深度、电极与壁的接近程度和组织安全性的严格要求，这非常具有挑战性。3d螺旋形的人类耳蜗解剖结构使这项任务更加复杂。许多形状可控电极已经被设计出来以满足要求，但它们仍然存在与形状控制有限、操作缓慢以及电气驱动的潜在危险相关的问题。本项目重点研究气动软机器人微触须及其单片集成的光学力传感器的联合利用，实现安全准确的CI电极插入。它们都是由柔软的弹性体制成，这极大地促进了CI电极的非侵入性，安全插入。仿生微触须的高机动性也将扩大可实现运动的范围，提高插入过程的精度。综上所述，敏捷形状控制与集成传感的融合最终将导致“自适应插入”，这是CI中一直在追求的。所有这些都将通过电气工程和结构工程这两个不同专业领域的研究人员的合作来实现，这将有助于科学和技术的融合。该项目还旨在通过对研究生和本科生在光学、MEMS、结构工程和计算力学等看似不相关但高度协同的主题进行联合指导，加强学术界的跨学科培训。它包括以K12科学技术示范和课外活动为基础，向代表性不足的人提供扩展计划。该项目的最终目标是通过软机器人、集成传感器的微触须安全准确地插入CI电极阵列。据此，本文提出了以下目标：(1)开发能够进行三维螺旋运动的软体机器人触手。这项任务将作为并行工作进行，包括PI的微加工和测试工作以及co-PI的计算设计，优化和分析。(2)基于弹性体的光学力传感器的发展。该任务的关键问题包括实现组织安全的完全非侵入式传感和与软机器人主体的整体临床安全集成。(3)制定插入过程完成后软体机器人形状的固定方案。关键问题是再次以临床安全的方式实现目标。这种独特协作的影响最终将超越持续集成。近年来，微型机器人和软机器人在康复和辅助技术中的重要性不断提高。这个项目将加速它们的融合，并为刚刚起步的“微型软机器人”领域增添动力。将形状控制和力感功能块与软执行器整体集成的计划也将有助于人类友好机器人领域，这一领域正在吸引机器人社区的强烈研究兴趣。由此产生的增材制造和形状控制技术将分别丰富增材制造和微型医疗机器人的武器库。

Cochlear implant (CI) is fast becoming the main rehabilitation aid for those who suffer from hair cell-related hearing impairments. The nation's current demography suggests that the CI adoption will increase at an accelerated pace for the foreseeable future, calling for more innovations in the CI technology. Of particular urgency is the need for safe and accurate schemes for CI electrode array insertion which is very challenging due to its stringent requirements on insertion depth, electrode-to-wall proximity, and tissue safety. The 3D-spiraling human cochlear anatomy further complicates the task. Many shape-controllable electrodes have been devised to meet the requirements but they still suffer from issues related to limited shape control, slow operation, and potential hazards of electrical actuation. This project focuses on achieving safe and accurate CI electrode insertion through joint utilization of pneumatic soft-robotic micro-tentacles and optical force sensors monolithically integrated with them. Both of them are made of soft elastomers, which greatly facilitates non-intrusive, safe insertion of the CI electrode. The high-level maneuverability of the bio-inspired micro-tentacle will also widen the scope of achievable motion and improve accuracy of the insertion process. Above all, the fusion of agile shape control and integrated sensing will eventually lead to "adaptive insertion" which has been incessantly pursued in CI. All of these will be achieved via the collaboration of two researchers with very different specialty areas, electrical engineering and structural engineering, which will contribute to the convergence in science and technology. This project also aims to strengthen cross-disciplinary training in academia through co-advising of graduate and undergraduate students in seemingly unrelated, yet highly synergistic topics such as optics, MEMS, structural engineering, and computational mechanics. It includes outreach plans to the underrepresented in based on K12 science and technology demonstrations and extra-curricular activities. This project's ultimate goal of safe and accurate insertion of CI electrode arrays through soft-robotic, sensor-integrated micro-tentacle. Accordingly, the following objectives have been lined up: (1) Development of soft-robotic tentacle capable of performing 3-dimensionally spiraling motion. This task will be carried out as a parallel effort encompassing the microfabrication and testing work by the PI and the computational design, optimization, and analysis by the co-PI. (2) Development of elastomer-based optical force sensors. The key issues of the task include the accomplishment of totally non-intrusive sensing for tissue safety and monolithic, clinically safe integration with the soft-robotic main body. (3) Development of the schemes to fix the shape of the soft-robot upon completion of the insertion process. The key issue is again achieving the goal in a clinically safe fashion. The impact of this unique collaboration will go beyond CI eventually. The importance of micro-robots and soft-robots in rehabilitation and assistive technologies has been in continuous increase in recent years. This project will expedite their fusion and add momentum to the fledgling field of "microscale soft-robotics." The plan to monolithically integrate the shape-control and force-sensing function blocks with the soft-actuator will also contribute to the field of human-friendly robotics which is attracting intense research interests from the robotics community. The resulting additive fabrication and shape-control techniques will enrich the arsenal of additive manufacturing and microscale medical robotics, respectively.