针对步行辅助中人机交互柔顺性和髋膝关节协调自律控制的问题，提出一种新型多关节协调自律控制方法，该方法基于中枢模式发生器（Central pattern generator，CPG）网络，同时具备单关节人机交流和多关节协调运动特性。建立左右侧髋、膝关节4个CPG单元及其对外交流机制，改善了各关节处的人机交互柔顺性；建立左右髋关节、左右膝关节CPG单元间的对称抑制连接及同侧髋膝关节CPG单元间的非对称内部抑制连接，获得双侧髋膝关节间的逆相位及同侧髋膝关节的自然相位，实现了人机交互环境下稳定的步行辅助。穿戴式步行试验证明了该方法对生成步行中自然髋、膝关节协调运动的有效性。最后，采用肌肉活动强度、步长和步行速度三个指标，运用对比试验的方法讨论和分析了步行辅助效果。
In order to ameliorate the flexibility and multi-joints autonomy in the walking assist environment, a novel notion of coordinated autonomous control method is introduced. The control method is based on CPGs network with dual mechanisms of external-communication and inner-inhibition. A CPG unit with its external-communication mechanism is connected to each left and right hip/knee joints to guarantee the independent HRI occurring at each joint. CPGs of the left and right hip/knee joints and CPGs of the hip and knee joints at the ipsilateral leg are connected in an inhibitory way to maintain an anti-phase relationship of the left and right hip/knee joints and natural phase difference between the hip-knee joints, and thus to realize stable walking assist in the complicated HRI environment. The validity of the proposal to generate the hip-knee joints coordination motion in walking is verified by wearable walking assist experiments. The assist effect of the proposed control has been discussed and analyzed using index of the muscle activity, step-length and walking speed.
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