行走过程中人体下肢受力模型的建立与验证
Establishment and Verification of a Mechanical Model for Analyzing the Forces Acted on Lower Limb During Walking

为了准确、简便地对人体行走过程中下肢的受力进行分析,构建了一个新的人体下肢力学模型:将人体的上半部分简化成固结至臀部的重物,将大腿、小腿和足部简化成3个刚杆,将踝关节、膝关节和髋关节简化成铰接点,将肌肉作用力简化成4对作用在刚杆上的未知力。针对该模型建立了相应的动力学方程,能够对足部和小腿的运动受力进行完整的描述。通过高速摄像机和足底测力台获取受试者的运动学和动力学数据,并使用APAS处理系统对数据进行处理,用于对动力学方程的求解,由此获得了下肢的受力状态。利用表面肌电仪测量了人体行走时的下肢肌肉电位,利用肌肉电位与肌肉力同时增大的原理,在一定程度上验证了模型的可靠性。研究结果表明:该模型能够较为真实地反映出下肢膝关节与踝关节的受力情况,具有较高的生物逼真度,可望为人体下肢运动机理的研究和下肢运动装备的开发提供参考。
To analyze the stress state of lower limb accurately and simply during walking, a novel mechanical model of human lower limb is proposed. The upper body is treated as a lumped weight; the thigh, calf and foot are considered as three rigid rods; the ankle, knee and hip are simplified as the link joints between the lumped weight and rods; and the muscle forces are simplified as four unknown forces acting on the rods. Based on this model, the corresponding dynamics equations are derived to describe the movement of feet and legs. Using the kinematic and dynamic data collected by high？？speed photography and plantar strainmeter, these equations are solved, and the stress state of lower limb is obtained. Moreover, the limb muscle potentials are measured by surface electromyography to verify the reliability of the present model. The results show that this model can reflect the stress state of knee and ankle with high biological fidelity, and provide guidelines to study the mechanism of human lower limb movement and develop lower limb sports equipment