...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Experimental Brain Research >Effect of speed manipulation on the control of aperture closure during reach-to-grasp movements
【24h】

Effect of speed manipulation on the control of aperture closure during reach-to-grasp movements

机译：达到抓握运动期间速度操纵对光圈关闭控制的影响

获取原文
获取原文并翻译 | 示例
   

获取外文期刊封面封底 >>

       
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

This study investigates coordination between hand transport and grasp movement components by examining a hypothesis that the hand location, relative to the object, in which aperture closure is initiated remains relatively constant under a wide range of transport speed. Subjects made reach-to-grasp movements to a dowel under four speed conditions: slow, comfortable, fast but comfortable, and maximum (i.e., as fast as possible). The distance traveled by the wrist after aperture reached its maximum (aperture closure distance) increased with an increase of transport speed across the speed conditions. This finding rejected the hypothesis and suggests that the speed of hand transport is taken into account in aperture closure initiation. Within each speed condition, however, the closure distance exhibited relatively small variability across trials, even though the total distance traveled by the wrist during the entire transport movement varied from trial to trial. The observed stability in aperture closure distance across trials implies that the hand distance to the object plays an important role in the control law governing the initiation of aperture closure. Further analysis showed that the aperture closure distance depended on the amplitude of peak aperture as well as hand velocity and acceleration. To clarify the form of the above control law, we analyzed four different mathematical models, in which a decision to initiate grasp closure is made as soon as a specific movement parameter (wrist distance to target or transport time) crosses a threshold that is either a constant value or a function of the above-mentioned other movement-related parameters. Statistical analysis performed across all movement conditions revealed that the control law model (according to which grasp initiation is made when hand distance to target becomes less than a certain linear function of aperture amplitude, hand velocity, and hand acceleration) produced significantly smaller residual errors than the other three models. The findings support the notion that transport–grasp coordination and grasp initiation is based predominantly on spatial characteristics of the arm movement, rather than movement timing.
机译：这项研究通过检查以下假设来研究手部运输和抓握运动组件之间的协调性：在较大的运输速度范围内，手部相对于物体的位置（在该位置相对于物体发起开孔的关闭）保持相对恒定。受试者在四种速度条件下进行抓握动作，例如慢速，舒适，快速但舒适和最大（即尽可能快）。孔径达到最大值后，手腕行进的距离（孔径闭合距离）随着速度条件下运输速度的增加而增加。这一发现驳斥了这一假设，并暗示在光圈关闭开始时考虑了手的运输速度。然而，在每种速度条件下，即使在整个运输过程中手腕在整个试验过程中移动的总距离因试验而异，闭合距离在试验中的变化也相对较小。跨试验观察到的孔径闭合距离的稳定性表明，到物体的手距离在控制孔径闭合开始的控制律中起着重要作用。进一步的分析表明，光圈关闭的距离取决于峰值光圈的幅度以及手的速度和加速度。为了阐明上述控制律的形式，我们分析了四种不同的数学模型，其中，一旦特定的运动参数（到目标的腕部距离或运输时间）超过阈值（即，恒定值或上述其他运动相关参数的函数。在所有运动条件下进行的统计分析表明，控制律模型（据此，当到目标的手部距离变得小于光圈幅度，手部速度和手部加速度的某个线性函数时，进行抓握操作）产生的残留误差明显小于其他三个模型。这些发现支持以下观点：运输-抓握协调和抓握启动主要基于手臂运动的空间特征，而不是运动时间。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号