非线性柔性层对接触面力与滑动检测的影响机理研究

An excellent performance of sensing forces and slip on a soft contact surface is crucial for a robot to grasp and manipulate a soft or fragile object with high efficiency and high reliability, such as an egg. The soft layer of a flexible tactile sensor for robotic application is often made of a rubber-like material, always with remarkable material nonlinearity and geometrical nonlinearity, and also with contact nonlinearity like dynamic friction phenomenon when contacting with an object. These nonlinearities increase greatly the complexity of sensor design and modeling. Many present tactile sensors often apply a linearized soft-layer model and soft contact model, however, limiting significantly the accuracy and dynamic performance of sensing forces and slip on a soft contact surface. With theoretic analysis, simulation and experiment research, this project plans to investigate nonlinear properties of a hyper-elastic soft-layer with large deformation to build a soft contact model, reveal the mechanism of nonlinear soft-layer influence on sensing forces and slip on a soft contact surface, determine the key parameters affecting on the accuracy and dynamic performance of sensing forces and slip, and then propose a method of sensing forces and slip on a soft contact surface with considering soft-layer nonlinear compensation. The achievement of this project would provide an important scientific basis for developing a corresponding tactile sensor, and also for a robot to grasp and manipulate a soft or fragile object with high efficiency and high reliability.

良好的柔性接触面力与滑动检测性能对于机器人高效可靠抓取柔软或易碎物体（如鸡蛋）至关重要。机器人触觉传感器的柔性层一般为橡胶类材料，具有显著的材料非线性和几何非线性，并且在与物体动态接触时还会产生动态摩擦现象（即接触非线性），这些非线性大大增加了触觉传感器设计及建模难度。目前许多触觉传感器研究均采用线性化的柔性层模型及柔性接触模型，限制了柔性接触面力与滑动的检测精度与动态性能。本课题将采用理论分析、数值模拟与实验研究相结合的方法，研究大变形超弹性柔性层的非线性表征及柔性接触建模，揭示非线性柔性层对接触面力与滑动检测的影响机理，提出影响柔性接触面力和滑动检测精度和动态特性的关键参数，并建立基于柔性层非线性补偿的接触面力与滑动检测方法，为开发相应触觉传感器以及实现机器人高效可靠抓取柔软或易碎物体提供科学依据。

良好的柔性接触面力与滑动检测性能对于机器人高效可靠抓取柔软或易碎物体（如鸡蛋）至关重要。本项目主要研究大变形超弹性柔性层的非线性表征及柔性接触建模、非线性柔性层对接触面力与滑动检测影响的理论分析、数值仿真及实验研究等内容。建立了橡胶类弹性体的柔性接触模型，提出了可以描述橡胶类弹性体材料非线性、几何非线性和接触非线性特征的无量纲参数，通过理论分析和数值仿真相结合的方法验证了该模型及无量纲参数的有效性，揭示了非线性柔性层对接触面力与滑动检测的影响机理；提出了基于橡胶类弹性体柔性接触模型的接触面力与滑动检测方法，完成了基于压敏单元阵列及电感阵列的柔性触觉传感器设计及样机制备，实现了可嵌入柔性层中的硅基压敏单元初步制备。实验结果表明，柔性触觉传感器样机能够实现柔性接触面三维力和滑动的在线检测，并能有效区分滑动方向，其中三维力检测的线性度为6.5%、重复性为3.3%，具有交叉耦合低、动态性能好的特点。本项目的研究为开发相应触觉传感器以及实现机器人高效可靠抓取柔软或易碎物体提供了科学依据。