七自由度仿生机器人系统冗余问题研究

Research on the Redundancy of Bionic Robot with Seven Degrees of Freedom

人体下肢的七自由度模型包括髋关节,膝关节和踝关节,但实际中下肢的运动只需要6个自由度即可,由于冗余引起的运动学干涉却没有现成的数学方法可以解决,同时又期望可穿戴机器人即外骨骼与人的交互能够同步,因而从运动学角度解决系统冗余问题。为了用数学方法描述冗余,定义一个旋转角度:由下肢大腿和小腿组成的平面绕髋关节和踝关节之间的虚拟轴的旋转角度。通过Matlab软件得到机器人的运动空间并与正常人体的运动空间进行比对,从而验证其可行性。

A human lower limb model has seven degrees of freedom, including hip, knee and ankle, but the actual movements of the lower limbs only need six degrees of freedom. Due to the kinematic redundancy caused by the interference can＇t be solved by mathematical methods while wearable robotic exoskeleton that can be synchronized with human interaction, thus it i tries to solve the problem from a kinematic point. In order to describe the redundancy mathematically, it defines a rotation angle： virtual axis between the hip and ankle joints of the lower extremities plane composed around the thigh and lower leg rotation. Obtained by Maflab software, it gets the robot motion space and compares it with the space of the normal movement of the body and verifies its feasibility.