基于堵塞原理的变刚度软体机器人设计与试验

Design and Testing of a Soft Robot with Variable Stiffness Based on Jamming Principles

软体机器人运动时具有高柔性,执行任务时又能展示出强刚度,在军事侦察、灾难救援等复杂环境探索与检测方面具有重要的应用价值。结合主动驱动的网络气动结构与被动驱动的堵塞机构的优势,提出实时变刚度的软体驱动器,研究其变刚度机理和动态建模方法。首先,提出了气动-堵塞机构耦合的软体驱动器模型;其次,利用赫兹接触模型,建立机器人运动数学模型,从理论上研究其变刚度形成机理;再次,利用有限元对气动驱动结构进行分析,研究空腔内压强、形状和大小对软体机器人弯曲角度的影响,并进行了优化;最后,制作了变刚度软体机械臂样机,验证了软体驱动器的变刚度性能与运动性能。该研究有望为变刚度软体机器人设计与刚度调控提供新的理论和技术支持。

A soft robot has high flexibility when performing tasks with moving and high stiffness, so it has important application in exploring and detecting complex environments. Based on the advantages of driving Pneu-Net and driven jamming mechanism, a soft robot with real-time variable stiffness and dynamic modeling methods is proposed. Firstly, the model of the soft actuator coupling pneumatic structure and jamming mechanism is established. Secondly, by using Hertzian contact model, a mathematical model of robot motion and theoretically investigated formation mechanisms of variable stiffness is built. Moreover, the pneumatically-driven structure is analyzed by using the finite element as well as the influences of pressure in cavities, considering shape and size of cavities on the bending angle of the soft robot are studied. Based on this, the pneumatically-driven structure is optimized. Finally, A prototype and testing of the soft robot arm with variable stiffness is implemented, which verified the variable stiffness and motion performances of the soft actuator. This study provides new theoretical and technical support for the design and stiffness control of a soft robot with variable stiffness.