Kanhere Elgar, Calais Théo, Jain Snehal, Plamootil Mathai Aby Raj, Chooi Aaron, Stalin Thileepan, Joseph Vincent Sebastian, Valdivia Y Alvarado Pablo
Digital Manufacturing and Design Centre (DManD), Singapore University of Technology and Design, Singapore, Singapore.
ICB UMR 6303 CNRS, Belfort-Montbéliard University of Technology, UTBM, Belfort, France.
Sci Robot. 2024 Dec 4;9(97):eadn4542. doi: 10.1126/scirobotics.adn4542.
Soft robotics hardware, with numerous applications ranging from health care to exploration of unstructured environments, suffers from limited life cycles, which lead to waste generation and poor sustainability. Soft robots combine soft or hybrid components via complex assembly and disassembly workflows, which complicate the repair of broken components, hinder upgradability, and ultimately reduce their life spans. In this work, an advanced extrusion-based additive manufacturing process, in situ free-form liquid three-dimensional printing (iFL3DP), was developed to facilitate functional upgrades and repairs in soft robots. A yield-stress hydrogel-a type of material that can maintain its shape until sufficient stress is applied-was first printed directly onto the robot surface, serving as a support for printing new components. This technique enabled the fabrication of advanced components with seamless integration onto already assembled robots. These components could combine multiple materials with intricate geometries, including overhangs and high-aspect ratio shapes, that are considerably challenging to manufacture and integrate via traditional methods such as casting. This approach was successfully applied to upgrade an existing soft robot by adding three advanced functionalities: whisker-like sensors for tactile feedback, a grasping mechanism, and a multifunctional passive whisker array. This study showcases the easy repairability of features, new and old, substantially extending the robot's life span. This workflow has potential to enhance the sustainable development of soft robots.
软机器人硬件在从医疗保健到非结构化环境探索等众多领域都有应用，但存在生命周期有限的问题，这导致了废物产生和可持续性较差。软机器人通过复杂的组装和拆卸工作流程来组合软质或混合部件，这使得损坏部件的修复变得复杂，阻碍了可升级性，并最终缩短了它们的使用寿命。在这项工作中，一种先进的基于挤压的增材制造工艺——原位自由形式液体三维打印（iFL3DP）被开发出来，以促进软机器人的功能升级和修复。一种屈服应力水凝胶——一种在施加足够应力之前能保持其形状的材料——首先被直接打印到机器人表面，作为打印新部件的支撑。这项技术能够制造出先进的部件，并无缝集成到已经组装好的机器人上。这些部件可以将多种具有复杂几何形状的材料结合在一起，包括悬垂结构和高纵横比形状，而通过传统方法如铸造来制造和集成这些形状具有相当大的挑战性。这种方法通过添加三种先进功能成功应用于升级现有的软机器人：用于触觉反馈的晶须状传感器、抓取机构和多功能被动晶须阵列。这项研究展示了新老部件易于修复的特点，大幅延长了机器人的使用寿命。这种工作流程有潜力促进软机器人的可持续发展。
