手臂屈伸运动中上位最优控制对外部速度力场的补偿适应

Adaption of Upper Level Optimal Control Module to the External Velocity Dependent Force Field during Reaching Movement

描述人体手臂适应外部力场的计算模型通常使用下位的前馈模块加以补偿,本研究提出当环境可以在内部模型中准确表达时,上位最优控制模块可以直接起到前馈补偿的作用。将与速度有关的力场(VF)施加到神经肌肉骨骼模型,并用最优控制方法进行仿真。仿真结果不仅与实验中手臂运动轨迹演化趋势相一致,同时与手臂末端阻抗椭圆也能很好的匹配。数值论证表明,人体可能仅通过调节上位最优控制模块中很少的参数就可以适应与补偿外部新环境。

In contrast to the traditional low-level compensation method,we proposed that when the environment could be expressed in the internal model,the upper-level optimal control module might directly play a role of feedforward compensation.In order to verify our proposal,we imposed velocity dependent force field in the simulation with the neuro-muscular-skeletal model and the optimal control methods.The outcome was qualitatively consistent with the experimental results of arm trajectory evolution and in line with the impedance ellipse of the end of arm.Numerical simulation demonstrated that brain might adapt to new environment by merely tuning a few parameters.