CAREER: Modular Origami in Soft Robotic Systems

该学院早期职业发展计划（CAREER）项目研究将特定机械性能设计成软机器人的新方法。软机器人是具有高度柔顺物理结构的智能机器——也就是说，当施加相对较小的力时，软机器人的身体会弯曲。高顺应性使软机器人比传统的刚性机器人在人周围更加安全，并且还允许软机器人获得多种形状，并比只有少量离散关节的机器人以更多的方式移动。由于易于弯曲的结构无法承载大负载，因此软机器人技术的一个主要挑战是创建仅在某些方向或仅在特定时间顺应的可变刚度结构。该项目提出了一种设计可变刚度软机器人的新方法，其灵感来自“折纸”或折纸的艺术和科学。受折纸启发的软机器人使用相对坚硬的材料薄片，这些材料可以沿着指定的折叠线弯曲；折叠图案可用于创建非常精确且复杂的等效机械性能。这种设计的灵活性与由橡胶和泡沫等材料制成的软机器人结构形成鲜明对比，后者的可实现强度受到材料本身固有柔软性的限制。在这个项目中，折纸启发的折叠模式用于创建具有指定合规行为的模块。然后可以通过组合许多此类模块来构建更大、能力更强的机器人。模块化折纸机器人的潜力示例包括有限空间中的软触手式操纵、全身和被动保形抓取以及可控形状变化。该项目的成果将使折纸启发的软机器人能够在家庭、医院和制造工厂中用作护理人员、同事和自我变形结构，从而促进国民健康和繁荣。与该项目相结合的教育活动将通过外展活动、高中实习和本科项目，使用折纸启发的机器人作为各年龄段学生的教学工具。该项目将建立模块化和可扩展的设计和制造方法，对机械性能进行表征和建模，并测试轻型折纸启发的模块化连续软体机器人的控制算法，以智能地执行操纵、抓取和形状变化任务。全面的综合研究和教育计划将解决（1）模块化折纸设计、制造和建模，以研究折纸启发模块的机械性能与其设计/制造参数之间的映射、使用分布式腱的电可寻址驱动、3D变形和外力的分布式软传感、以及用于动态建模的外部载荷下连续截面变形的计算高效的回旋曲线公式； （2）赋予软机器人智能的控制方法，以实现与环境的安全力/位置交互，在状态空间协同结合运动规划和控制，以及大规模模块化系统的超冗余，以最小的驱动和传感要求变形为所需的形状。结果将通过连续手臂操纵、全身包裹和利用保形接触进行抓取、通过极大自由度折纸驱动进行形状变化和刚度控制等方面的验证案例研究进行评估。该奖项反映了 NSF 的法定使命，并通过使用基金会的智力优点和更广泛的影响审查标准进行评估，被认为值得支持。

This Faculty Early Career Development Program (CAREER) project studies new ways to engineer specified mechanical properties into soft robots. Soft robots are intelligent machines with a highly compliant physical structure -- that is, the body of the soft robot will bend when relatively small forces are applied to it. High compliance makes soft robots much safer around people than traditional rigid robots, and also allows soft robots to attain a variety of shapes and to move in many more ways than robots with only a small number of discrete joints. Because structures that are easy to bend cannot carry large loads, a major challenge in soft robotics is to create variable-stiffness structures that are compliant only in certain directions, or only at specific times. This project presents a new approach to engineering variable-stiffness soft robots, inspired by the art and science of "origami," or paper folding. Origami-inspired soft robots use thin sheets of relatively stiff materials that are made bendable along designated fold lines; the folding pattern can be used to create very precise and complex equivalent mechanical properties. This engineered flexibility contrasts with soft robot structures made of materials such as rubbers and foams, which are limited in their achievable strength by the intrinsic softness of the material itself. In this project, origami-inspired folding patterns are used to create modules with a specified compliant behavior. Larger and more capable robots can then be built up by combining many such modules. Examples of the potential of modular origami-inspired robots include soft tentacle-like manipulation in confined spaces, whole-body and passive conformal grasping, and controllable shape change. The results of the project will advance the national health and prosperity, by enabling origami-inspired soft robots to be used in homes, hospitals, and manufacturing sites, as care-givers, co-workers, and self-morphing structures. Educational activities integrated with this project will use origami-inspired robots as teaching tools for students of all ages through outreach activities, high-school internships, and undergraduate projects. This project will establish modular and scalable design and fabrication methods, characterize and model mechanical properties, and test control algorithms for lightweight origami-inspired modular continuum soft robots to intelligently perform manipulation, grasping, and shape-change tasks. A comprehensive integrated research and education plan will address (1) modular origami design, fabrication, and modeling, to study the mapping between mechanical properties of origami-inspired modules and their design/fabrication parameters, electrically addressable actuation using distributed tendons, distributed soft sensing of 3-D deformation and external forces, and computationally efficient clothoid formulation of continuum section deformations under external loads for dynamic modeling; (2) Control methods that endow soft robots with intelligence, to enable safe force/position interaction with the environment, synergistically combining motion planning and control at the state space, and hyper-redundancy of large scale modular systems to morph into desired shapes with minimal actuation and sensing requirements. Results will be evaluated through validation case studies in continuum arm manipulation, whole-body wrapping and utilizing conformal contact for grasping, and shape change and stiffness control by very large degree-of-freedom origami actuation.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.