Mechanics of Bioinspired Soft Slender Actuators for Programmable Multimodal Deformation

细长软致动器是一种一维比其他维度大得多的主动结构，在自然界中普遍存在。一般来说，这些结构具有无限数量的自由度，这使得它们具有高精度操作的挑战性。迫切需要有效的理论和计算工具来指导执行机构的高精度设计。受象鼻子运动的启发，本项目从根本上研究了可编程多模态驱动下软细长致动器的力学。降维使所提出的模型计算效率高、成本低、鲁棒性强，特别是在大变形和逆分析方面。提议的活动可以提供机会，将软机器人研究从试错方法转变为基于科学的设计策略。这项工作可以作为促进STEM教育的平台。验证后，该模型将在一个开源模拟器中实现，供软机器人社区的学生、教育工作者和研究人员使用。该模型将为可穿戴设备、柔性电子设备和外科机器人等各种高精度应用中的软机器人提供新的设计策略。本项目整合理论建模、计算力学、材料多物理场、实验力学和机器学习来解决研究问题。将力学模型与实验验证相结合，建立开源仿真平台，对此类执行器进行优化设计。潜在的结构是活动细丝理论，它利用了维度缩减的概念——从一个完全三维的结构到一个活动的基尔霍夫棒——通过只通过延伸、曲率和扭转来描述变形。它将创建一个开源模拟器，与更广泛的软机器人社区共享。该研究将首先建立一种新的力学理论来预测柔性细长作动器末端执行器的运动轨迹。然后，它可以作为优化末端执行器轨迹的基础。该理论将通过液晶弹性体纤维的驱动实验进行验证。该项目将涉及理论和实验的同时发展，并将迭代修改这两个活动，最终建立一个实验验证的理论和一个具有高预测精度的优化设计模型。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Soft slender actuators are active structures that have one dimension much larger than the other dimensions, and are ubiquitous in nature. In general, these structures have an infinite number of degrees of freedom, making them challenging to manipulate with high precision. There is an urgent need for efficient theoretical and computational tools to guide actuator design for high precision actuation. Inspired by elephant-trunk motion, this project fundamentallly investigates the mechanics of soft slender actuators under programmable multimodal actuation. Dimensional reduction makes the proposed model computationally efficient, inexpensive, and robust, especially with a view towards large deformations and inverse analyses. Proposed activties can provide opportunities to transform soft robotic research from a trial-and-error approach to a science-based design strategy. The work can serve as a platform to promote STEM education. After validation, the model will be implemented in an open-source simulator that can be used by students, educators, and researchers in the soft robotics community. The model will inform new design strategies for soft robots in various high-precision applications including wearable devices, flexible electronics, and surgical robotics.This project integrates theoretical modeling, computational mechanics, material multiphysics, experimental mechanics, and machine learning to address the research problem. Mechanics models and experimental validation will be combined to establish an open-source simulation platform to optimize the design of such actuators. The underlying construct is the active filament theory that harnesses the concept of dimensional reduction—from a fully three-dimensional structure to an active Kirchhoff rod—by describing deformation exclusively through extension, curvature, and torsion. It will create an open-source simulator that will be shared with the broader, soft robotics, community . The research will first establish a new mechanics theory to predict the trajectory of the end effector of a soft slender actuator. It can then serve as the foundation to optimize the trajectory of the end effector. The new theory will be validated via experiments through the actuation of liquid crystal elastomer fibers. This project will involve the simultaneous development of theory and experiments and will iteratively revise both activities to ultimately establish an experimentally validated theory and an optimal design model with high predicting accuracy.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.