Abstract

Soft robots are intrinsic compliant machines capable of realizing complex movements by the deformation of their own body. They promise to overcome limitations presented by rigid robots in unstructured environments and in handling fragile objects. One of the recent interests in soft robotics is the development of techniques to design improved soft actuators. In this context, this work presents a density-based topology optimization formulation to design soft actuators driven by pressure loads. This formulation solves design-dependent load problems using mixed displacement-pressure finite elements to synthesize compliant mechanisms actuated by pressure loads. The objective of the optimization is to maximize the output displacement in a given direction while constraining the material volume. A projection technique is proposed to circumvent the appearance of open designs which are of non-interest. The optimization is solved by using an interior point algorithm (IPOPT). Three numerical examples are explored to evaluate the effectiveness of the formulation: a bending, a linear, and an inverter actuator. The numerical results show that the proposed projection technique is successful in finding optimized closed designs for the studied problems.

中文翻译：

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拓扑优化应用于由压力负载驱动的执行器的设计

摘要

软机器人是内在的兼容机器，能够通过自身身体的变形来实现复杂的运动。他们承诺将克服刚性机器人在非结构化环境和处理易碎物品中所带来的限制。软机器人技术最近的兴趣之一是开发设计改进的软致动器的技术。在这种情况下，这项工作提出了一种基于密度的拓扑优化公式，以设计由压力负载驱动的软执行器。该公式使用混合位移-压力有限元解决了与设计有关的载荷问题，以合成由压力载荷驱动的顺应机构。优化的目的是在给定方向上最大化输出位移，同时限制材料体积。提出了一种投影技术来规避不感兴趣的开放设计的外观。通过使用内部点算法（IPOPT）解决了优化问题。探索了三个数值示例来评估配方的有效性：弯曲，线性和逆变器执行器。数值结果表明，所提出的投影技术可以成功地找到针对所研究问题的优化封闭设计。