Hettich Georg, Assländer Lorenz, Gollhofer Albert, Mergner Thomas
Neurological University Clinic, Neurocenter, Breisacher Str. 64, 79106 Freiburg, Germany; Institute for Sport and Sportscience, University of Freiburg, Schwarzwaldstr. 175, 79117 Freiburg, Germany.
Neurological University Clinic, Neurocenter, Breisacher Str. 64, 79106 Freiburg, Germany; Institute for Sport and Sportscience, University of Freiburg, Schwarzwaldstr. 175, 79117 Freiburg, Germany.
Hum Mov Sci. 2014 Oct;37:123-46. doi: 10.1016/j.humov.2014.07.004. Epub 2014 Aug 24.
Human sensorimotor control involves inter-segmental coordination to cope with the complexity of a multi-segment system. The combined activation of hip and ankle muscles during upright stance represents the hip-ankle coordination. This study postulates that the coordination emerges from interactions on the sensory levels in the feedback control. The hypothesis was tested in a model-based approach that compared human experimental data with model simulations. Seven subjects were standing with eyes closed on an anterior-posterior tilting motion platform. Postural responses in terms of angular excursions of trunk and legs with respect to vertical were measured and characterized using spectral analysis. The presented control model consists of separate feedback modules for the hip and ankle joints, which exchange sensory information with each other. The feedback modules utilize sensor-derived disturbance estimates rather than 'raw' sensory signals. The comparison of the human data with the simulation data revealed close correspondence, suggesting that the model captures important aspects of the human sensory feedback control. For verification, the model was re-embodied in a humanoid robot that was tested in the human laboratory. The findings show that the hip-ankle coordination can be explained by interactions between the feedback control modules of the hip and ankle joints.
人类的感觉运动控制涉及节段间协调，以应对多节段系统的复杂性。直立姿势期间髋部和踝部肌肉的联合激活代表髋-踝协调。本研究假设这种协调源自反馈控制中感觉层面的相互作用。该假设通过基于模型的方法进行检验，即将人体实验数据与模型模拟进行比较。七名受试者闭眼站在前后倾斜的运动平台上。使用频谱分析测量并表征了躯干和腿部相对于垂直方向的角偏移方面的姿势反应。所提出的控制模型由用于髋关节和踝关节的单独反馈模块组成，这些模块相互交换感觉信息。反馈模块利用传感器得出的干扰估计值而非“原始”感觉信号。人体数据与模拟数据的比较显示出密切的对应关系，表明该模型捕捉到了人类感觉反馈控制的重要方面。为进行验证，该模型被重新应用于在人体实验室中进行测试的人形机器人。研究结果表明，髋-踝协调可通过髋关节和踝关节反馈控制模块之间的相互作用来解释。
