Department of Biomedical Engineering, University of California, Davis, One Shields Ave, Davis, CA 95616, USA.
J Theor Biol. 2012 Oct 21;311:1-7. doi: 10.1016/j.jtbi.2012.06.023. Epub 2012 Jul 7.
Although compliance (visco-elasticity) of a prosthesis has the potential to affect clinically relevant aspects of a lower extremity amputee's gait, it is currently unknown what the compliant parameter values should be. Here, a simple dynamical model is used to approximate walking with a compliant prosthesis. An exhaustive search is used to identify the optimal compliant element parameter set in terms of the model's stability as measured by the reciprocal of the gait sensitivity norm (rGSN). We identified a parameter set yielding a 17% larger rGSN than the best commercially available prosthesis; however, this is unlikely to be the global optimum for the physically realizable visco-elastic parameter space. Due to the nonlinear effects of the compliant elements, it is difficult to make generalizations about speed and step length, such difficulties are not present with simpler contact models. However, there is some evidence to support a possible trade-off between efficiency and stability.
尽管假肢的顺应性（粘弹性）有可能影响下肢截肢者步态的临床相关方面，但目前尚不清楚顺应性参数值应该是多少。在这里，使用一个简单的动力学模型来模拟具有顺应性假肢的行走。通过对步态灵敏度范数（rGSN）的倒数进行测量，我们使用穷举搜索来确定最佳的顺应性元件参数集，以确定模型的稳定性。我们确定了一组参数，使 rGSN 比市场上最好的商业可用假肢大 17%；然而，这不太可能是物理上可实现的粘弹性参数空间的全局最优。由于顺应性元件的非线性效应，很难对速度和步长进行概括，而使用更简单的接触模型则不存在这些困难。然而，有一些证据支持效率和稳定性之间可能存在权衡。
