Intelligent Polymer Materials as Actuators and Sensors for Soft Robotics Applications (IntPoly)

IntPoly的“智能聚合物材料作为软机器人应用的致动器和传感器”项目是一个新的软材料科学项目，将在SPP 2100“软材料机器人”的当前活动中实施。IntPoly基于Sabine Ludwigs教授的跨学科专业知识（高分子化学，材料科学）和教授霍尔格Steeb（流变学，材料建模）并旨在新型智能聚合物双层和3D打印架构，其可以使其机械性能适应外部场，并且一方面用作应变传感器，另一方面用作致动器，并用于软机器人设备的致动硬化。另一只手导电聚合物（CP）如聚（乙撑二氧噻吩）：聚（苯乙烯磺酸盐）（PEDOT：PSS）已被确定为主动适应和响应电场的智能材料。应将高度可拉伸材料制备为柔性机器人的顺应性材料，其中涉及CP与水凝胶的组合或与弹性体（如Ecoflex和Dragonskin）的混合物。该项目分为3个工作包：在WP 1中，应系统地表征散装和双层薄膜的温度、湿度、电导率和流变性能之间的复杂相互作用。为了用作致动器和致动硬化（可变刚度），将应用焦耳加热的概念，即局部加热导致双层中的曲率变化和智能材料的杨氏模量增加。对于应变传感器，电阻应作为大应变材料应变的函数进行测量。 WP2应用3D打印技术来创建复杂的架构，这应该会导致更复杂的形状变化和功能分级的样品，从而可以创建调谐的智能结构。应开发允许有限元（FE）模拟的基于连续体的有限变形模型。数值模拟应支持形状变化的预测，并允许对“复杂”致动器几何形状的内部应力状态进行研究，这些致动器几何形状由具有不均匀分布的材料特性的样品组成。一方面，应变传感器应与软弹性体机器人系统相结合，并针对形状、位置和方向检测进行优化。另一方面，电场诱导硬化该项目将增加该领域当前的挑战，包括材料选择、新型软材料的设计和工程以及相应的制造工艺。（例如，3D打印）用于柔软和可拉伸的致动器和传感器，以及它们在演示器中的适当放置。

The project “Intelligent Polymer Materials as Actuators and Sensors for Soft Robotics Applications”, IntPoly, is a new soft materials science project which shall be implemented into current activities of the SPP 2100 on “Soft Material Robotics”. IntPoly is based on the coupled interdisciplinary expertise of Prof. Sabine Ludwigs (polymer chemistry, materials science) and Prof. Holger Steeb (rheology, material modelling) and aims at novel intelligent polymer bilayer and 3D printed architectures which can adapt their mechanical properties to external fields and which shall be used as strain sensors on the one hand and as actuators and for actuated stiffening of soft robotics devices on the other hand. Conducting polymers (CPs) such as poly(ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) have been identified as intelligent materials which actively adapt and respond to electric fields. Highly stretchable materials shall be prepared as compliant materials for soft robotics which involves the combination of CPs either with hydrogels or as blends with elastomers such as Ecoflex and Dragonskin. The project is structured in 3 workpackages: In WP1 a systematic characterization of the complex interplay between temperature, humidity, electrical conductivity and rheological properties of bulk and bilayer films shall be performed. For the use as actuators and actuated stiffening (variable stiffness) the concept of Joule heating will be applied, i.e. local heating leads to curvature changes in bilayers and increased Young’s moduli of the intelligent materials. For strain sensors the resistance shall be measured as function of strain for large strain materials. WP2 applies 3D printing technology to create complex architectures which should result in more complex shape changes and functionally-graded samples allowing to create tuned intelligent structures. Continuum based finite deformation models shall be developed which allow for Finite Element (FE) simulations. The numerical simulations shall support the prediction of shape changes and allow for the investigation of the internal stress states of “complex” actuator geometries consisting of samples with heterogeneously distributed material properties.A very strong collaboration with the SPP2100 demonstrator projects TENDON and SMART is planned in WP3. On the one hand, strain sensors shall be coupled with soft elastomer robotics systems and optimized for shape, position and orientation detection. On the other hand, electric field induced stiffening (“stiffening on demand”) of the intelligent layers and architectures shall be connected with existing soft elastomer robotics.The project will add to current challenges of the field including material choice, design and engineering of novel soft materials with corresponding fabrication processes (e.g. 3D printing) for soft and stretchable actuators and sensors, and their appropriate placement in demonstrators.