The constrained control of force and position in multi-joint movements
The constrained control of force and position in multi-joint movements
复制标题
多关节运动中力和位置的约束控制
DOI：
10.1016/0306-4522(92)90019-x
复制
发表时间：
1992
期刊：
影响因子：
3.3
通讯作者：
Wilbert W.L.M. Van Woensel
中科院分区：
文献类型：
--
作者：
G. V. I. Schenau;P.J.M. Boots;G. Groot;R. J. Snackers;Wilbert W.L.M. Van Woensel
在许多手臂或腿部运动中，手或脚必须对环境施加外力。基于循环的逆动力学分析，表明控制外力方向所需的关节中净力矩的分布往往与与此任务相关的关节位移方向相反。采用膜片分析和踏板力测量的方法，获得了5名经验丰富的自行车运动员在测力仪骑行过程中的动力学和运动学数据。基于连接段模型的逆动力学分析得出了8块腿部肌肉的净关节力矩、关节功率和肌肉缩短速度。通过表面肌电图获得肌肉的激活模式。结果表明，髋关节、膝关节和踝关节的旋转传递到踏板的平移受到冲突要求的约束。这发生在产生关节动力所需的关节力矩和确定踏板上的力的方向所需的力矩之间，这个方向允许这个力在踏板上做功。单关节激动剂及其双关节拮抗剂的共同激活似乎为这些相互冲突的要求提供了一种独特的解决方案：双关节肌肉似乎能够通过调节关节上净力矩的相对分布来控制踏板上外力的预期方向，而单关节肌肉似乎主要在缩短位置时被激活，从而有助于积极工作。举例说明了这种力（外部）和位置（关节）约束控制的普遍性。根据这项研究和已发表的数据，我们认为不同的过程可能是单关节和双关节肌肉控制组织的基础。
In many arm or leg movements the hand or foot has to exert an external force on the environment. Based on an inverse dynamical analysis of cycling, it is shown that the distribution of net moments in the joints needed to control the direction of the external force is often opposite to the direction of joint displacements associated with this task. Kinetic and kinematic data were obtained from five experienced cyclists during ergometer cycling by means of film analysis and pedal force measurement. An inverse dynamic analysis, based on a linked segments model, yielded net joint moments, joint powers and muscle shortening velocities of eight leg muscles. Activation patterns of the muscles were obtained by means of surface electromyography.The results show that the transfer of rotations in hip, knee and ankle joints into the translation of the pedal is constrained by conflicting requirements. This occurs between the joint moments necessary to contribute to joint power and the moments necessary to establish a direction of the force on the pedal which allows this force to do work on the pedal. Co-activation of mono-articular agonists and their bi-articular antagonists appear to provide a unique solution for these conflicting requirements: bi-articular muscles appear to be able to control the desired direction of the external force on the pedal by adjusting the relative distribution of net moments over the joints while mono-articular muscles appear to be primarily activated when they are in the position to shorten and thus to contribute to positive work.Examples are given to illustrate the universal nature of this constrained control of force (external) and position (joint). Based on this study and published data it is suggested that different processes may underlie the organization of the control of mono- and bi-articular muscles.