下肢外骨骼机器人踝关节混合柔性驱动设计与研究

Design and Research of Hybrid Compliance Drive Ankle Joint for Lower Extremity Exoskeleton Robots

为了提高人机交互的安全性、舒适性以及对复杂非结构化环境的适应能力,设计了一种基于串联弹性驱动和刚性驱动混合的新型下肢外骨骼机器人踝关节。在电机与外骨骼机器人负载之间引入线性弹簧组以实现柔性驱动,对机器人脚部触地等冲击起到缓冲减振作用。设计了碟刹装置实现刚性驱动功能,以快速精确的响应人踝关节的摆动,避免人机运动偏差。建立了踝关节的动力学模型,通过频域特性分析方法得到了踝关节在不同参数特性下的稳定性以及力跟随特性。仿真实验验证了外骨骼机器人踝关节在受到冲击时的缓冲减振特性,并且验证了模型的准确性和有效性。

In order to improve the safety and comfort of human-machine interaction and its adaptability to complex unstructured environments, a new type of ankle joint based on a series of elastic drive and rigid drive hybrid is designed between the motor and exoskeleton robot. Linear spring groups were introduced to achieve flexible driving and to absorb the ground reaction force and other impact vibration. At the same time, a disk brake device was designed to retain the rigid drive function to quickly and accurately respond to the motion of the human ankle joint and to reduce human-machine movement deviation. The dynamic model of the ankle joint was established. The stability of the hybrid driver under different parameters and the force following characteristics were obtained through frequency domain analysis. Through simulation experiments, the cushioning and damping characteristics of the exoskeleton ankle joint are verified, and the accuracy and effectiveness of the model are verified as well.