A closed-loop stepper motor waist-pull system for inducing protective stepping in humans
A closed-loop stepper motor waist-pull system for inducing protective stepping in humans
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DOI：
10.1016/s0021-9290(98)00017-7
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发表时间：
1998-04-01
影响因子：
2.4
通讯作者：
Rogers, MW
中科院分区：
文献类型：
--
作者：
Pidcoe, PE;Rogers, MW
过去用于诱导保护性步进以保持人类站立平衡的方法要么缺乏对跌倒初始条件的控制灵活性，要么涉及相当大的质量，限制了系统的移动性。本报告描述了用于引起保护性步进反应的步进电机闭环腰部牵引系统的设计和功能。应用负载-运动曲线组合进行的台架测试表明，大于 204 N 的力水平会导致性能下降，这完全在人体实验中遇到的水平之内。光学编码器反馈设计允许每步的位置精度为 0.00225 毫米。对指定速度与记录速度的回归分析得出了可接受的拟合结果 (r(2) = 0.99)。平均上升时间为 63.0 +/- 18.0 (SD) ms，并且在器件的负载限制范围内保持一致。在人体实验中，重复的扰动得到了一致的实现。尽管存在轻微的位置滞后趋势，但对于不同几何形状、体重和惯性的受试者，所应用的运动轮廓在骨盆水平上通常具有可比性。该方法可以灵活、准确地控制扰动引起的跌倒的初始条件以引发步数。系统尺寸和可移动性使其能够应用于临床环境。 (C) 1998 Elsevier Science Ltd. 保留所有权利。
Past approaches for inducing protective stepping to preserve standing balance in humans have either lacked the flexibility of control over the initial conditions of falling, or involved considerable mass which limits mobility of the system. This report describes the design and function of a stepper motor closed-loop waist-pull system for evoking protective stepping responses. Bench testing with applied load-motion profile combinations indicated performance degradation for force levels greater than 204 N which was well within the levels encountered in human experiments. An optical encoder feedback design allowed a positional accuracy of 0.00225 mm per step. A regression analysis of specified versus recorded velocities resulted in an acceptable fit (r(2) = 0.99). The mean rise time was 63.0 +/- 18.0 (SD) ms and was consistent up to the load limits of the device. In human experiments repeated perturbations were consistently realized. Applied motion profiles were generally comparable at the pelvic level for subjects of different geometry, weight, and inertia despite a tendency for slight positional lag. The method allows flexible and accurate control of the initial conditions of a perturbation-induced fall to elicit steps. The system dimensions and moveability allow it to be implemented into clinical environments. (C) 1998 Elsevier Science Ltd. All rights reserved.