Once-per-step control of ankle-foot prosthesis push-off work reduces effort associated with balance during walking.
Once-per-step control of ankle-foot prosthesis push-off work reduces effort associated with balance during walking.
复制标题
对脚踝脚踝假体的每步控制一次，推断工作可以减少与步行过程中与平衡相关的工作。
DOI：
10.1186/s12984-015-0027-3
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发表时间：
2015-05-01
影响因子：
5.1
通讯作者：
Collins SH
中科院分区：
文献类型：
--
作者：
Kim M;Collins SH
膝下截肢的人在行走时更难保持平衡，但很少有研究探讨通过主动假肢控制来增强平衡。我们以前使用的动力学模型表明，假肢踝关节推离工作影响矢状面和额状面动力学，并适当的逐步控制推离工作可以提高稳定性。我们假设这种方法可以应用于机器人假肢，以部分满足人类行走的主动平衡要求，从而减少使用该设备的人的平衡相关活动和相关努力。我们对模拟截肢的人类参与者（N = 10）进行了实验。假体踝关节蹬离工作在每一步上都是不同的，预计要么稳定，不稳定，或对平衡没有影响。平均踝关节推离工作，已知影响的努力，保持不变的条件。稳定控制器命令更多的推离工作的步骤时，在对侧脚跟罢工的时刻，质量中心的内外侧速度比平时低。不稳定的控制器执行相反的关系，而中立的控制器保持恒定的推离工作，无论身体状态。随机干扰着陆脚的角度和认知分散任务，进一步挑战参与者的平衡。我们测量了代谢率，脚放置运动学，压力中心运动学，分心任务的性能，和用户的偏好在每种条件下。我们期望稳定控制器减少主动控制的平衡和平衡相关的努力，为用户，提高用户的喜好。与无控制和去稳定控制的条件相比，最佳稳定控制剂分别使代谢率降低5.5%（p = 0.003）和8.5%（p = 0.02），并且使步长可变性降低10.0%（p = 0.009）和10.7%（p = 0.03）。参与者倾向于选择稳定控制器。这些影响不是由于平均蹬离功的差异（在不同条件下均未发生变化）或平均步态力学（也未发生变化）。相反，受益来自逐步调整假体的行为，以应对足跟着地时的内外侧速度变化。一步一次的假肢踝关节蹬离工作的控制可以减少步行过程中的脚放置和平衡相关的代谢能量使用的主动控制。本文的在线版本（doi：10.1186/s12984-015-0027-3）包含补充材料，可供授权用户使用。
Individuals with below-knee amputation have more difficulty balancing during walking, yet few studies have explored balance enhancement through active prosthesis control. We previously used a dynamical model to show that prosthetic ankle push-off work affects both sagittal and frontal plane dynamics, and that appropriate step-by-step control of push-off work can improve stability. We hypothesized that this approach could be applied to a robotic prosthesis to partially fulfill the active balance requirements of human walking, thereby reducing balance-related activity and associated effort for the person using the device. We conducted experiments on human participants (N = 10) with simulated amputation. Prosthetic ankle push-off work was varied on each step in ways expected to either stabilize, destabilize or have no effect on balance. Average ankle push-off work, known to affect effort, was kept constant across conditions. Stabilizing controllers commanded more push-off work on steps when the mediolateral velocity of the center of mass was lower than usual at the moment of contralateral heel strike. Destabilizing controllers enforced the opposite relationship, while a neutral controller maintained constant push-off work regardless of body state. A random disturbance to landing foot angle and a cognitive distraction task were applied, further challenging participants’ balance. We measured metabolic rate, foot placement kinematics, center of pressure kinematics, distraction task performance, and user preference in each condition. We expected the stabilizing controller to reduce active control of balance and balance-related effort for the user, improving user preference. The best stabilizing controller lowered metabolic rate by 5.5% (p = 0.003) and 8.5% (p = 0.02), and step width variability by 10.0% (p = 0.009) and 10.7% (p = 0.03) compared to conditions with no control and destabilizing control, respectively. Participants tended to prefer stabilizing controllers. These effects were not due to differences in average push-off work, which was unchanged across conditions, or to average gait mechanics, which were also unchanged. Instead, benefits were derived from step-by-step adjustments to prosthesis behavior in response to variations in mediolateral velocity at heel strike. Once-per-step control of prosthetic ankle push-off work can reduce both active control of foot placement and balance-related metabolic energy use during walking. The online version of this article (doi:10.1186/s12984-015-0027-3) contains supplementary material, which is available to authorized users.
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影响因子：
2.4
作者：
Donelan, JM;Shipman, DW;Kuo, AD
通讯作者：
Kuo, AD
DOI：
10.1098/rspb.2011.1194
发表时间：
2012-02-07
影响因子：
4.7
作者：
Herr, Hugh M.;Grabowski, Alena M.
通讯作者：
Grabowski, Alena M.
影响因子：
4.6
作者：
Dean, J. C.;Alexander, N. B.;Kuo, A. D.
通讯作者：
Kuo, A. D.
影响因子：
3.3
作者：
Kim, Jung-Yup;Park, Ill-Woo;Oh, Jun-Ho
通讯作者：
Oh, Jun-Ho
影响因子：
1.5
作者：
Hagberg, K;Brånemark, R
通讯作者：
Brånemark, R