Kinematic networks
Kinematic networks
复制标题
运动网络
作者：
F. Ivaldi;P. Morasso;R. Zaccaria
从机械角度来看，灵长类动物的运动控制涉及一个高度冗余的系统——冗余来自于一组独立可控变量和一组系统变量之间的不平衡。其结果是出现了一大类不适定问题，这些问题很难找到唯一的解。例如(i)确定手臂关节旋转的协调模式以规划手的运动轨迹的问题；（ii）确定一组所需关节扭矩的肌肉力分布的问题。不适定问题，一般来说，需要正则化的方法，允许拼写可接受的，如果不是唯一的，解决方案。在运动系统的情况下，我们提出基本的正则化机制是由肌肉的弹性特性产生的势场提供的，根据我们称之为“被动运动范式”的组织原则。回顾了这一假设的生理学基础，并提出了一个“运动网络”（K-net）模型来表达弹性所隐含的运动转换和因果关系。此外，它还展示了如何在特定任务的背景下从运动学“身体模型”中获得K-nets。两个特别重要的结果是：(i)对闭合和开放运动链的统一处理，以及（ii）开发了一种自动生成任意拓扑运动方程的新方法。此外，该模型类似于“电机等效”的概念，因为它提供了由可调谐电机阻抗参数化的电机等效轨迹家族。
Motor control in primates relates to a system which is highly redundant from the mechanical point of view — redundancy coming from an imbalance between the set of independently controllable variables and the set of system variables. The consequence is the manifestation of a broad class of ill-posed problems, problems for which it is difficult to identify unique solutions. For example (i) the problem of determining the coordinated patterns of rotation of the arm joints for a planned trajectory of the hand; (ii) the problem of determining the distribution of muscle forces for a desired set of joint torques. Ill-posed problems, in general, require regularization methods which allow to spell acceptable, if not unique, solutions. In the case of the motor system, we propose that the basic regularization mechanism is provided by the potential fields generated by the elastic properties of muscles, according to an organizational principle that we call “Passive Motion Paradigm”. The physiological basis of this hypothesis is reviewed and a “Kinematic Network” (K-net) model is proposed that expresses the kinematic transformations and the causal relations implied by elasticity. Moreover, it is shown how K-nets can be obtained from a kinematic “Body Model”, in the context of a specific task. Two particularly significant results are: (i) the uniform treatment of closed as well as open kinematic chains, and (ii) the development of a new method for the automatic generation of kinematic equations with arbitrary topology. Moreover, the model is akin to the concept of “motor equivalence” in the sense that it provides families of motor equivalent trajectories parametrized by tunable motor impedances.
多关节手臂姿势和运动的调节。
影响因子：
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作者：
Bizzi,E;Mussa-Ivaldi,FA;Hogan,N
通讯作者：
Hogan,N
影响因子：
14.5
作者：
ABEND, W;BIZZI, E;MORASSO, P
通讯作者：
MORASSO, P