Silesian University of Technology, Faculty of Biomedical Engineering, Department of Biomechatronics, Gliwice, Poland.
Institute of Sport Sciences, The Jerzy Kukuczka Academy of Physical Education in Katowice, Katowice, Poland.
Acta Bioeng Biomech. 2020;22(1):127-134.
Analysis of human gait as well as diagnosis of human locomotion organ should always be conducted with velocity of gait equal to Preferred Walking Speed (PWS). The literature review shows that the PWS value is not the same in real and virtual environment. The aim of this study was to determine PWS values in both environments and to specify values of parameters used in equations enabling PWS calculations on the basis of lower limb length.
Research-related tests involved 40 subjects walking on the treadmill and wearing HMD goggles. The spatial scenery made participants feel like during a walk in the park. The tests included measurements of displacements of the COP, allowing for the calculation of the Lyapunov exponent and Floquet Multiplier. Both coefficients were used to identify stability at various gait velocities.
The analysis revealed that the PWS in relation to gait on the treadmill with VR was lower than the PWS without VR. The final stage of research involved the determination of new values of coefficients of the formula enabling the identification of the velocity of comfort of gait in VR.
Obtained results proved that PWS in real and virtual environment are different. The lower values were obtained for measurements in VR. On the basis of these results, value of the "a" coefficient, used in PWS calculations on the basis of lower limb length, was re-determined. The new value makes it possible to assess PWS for gait conducted on treadmill in virtual environment, what can be very important in gait evaluation.
分析人类步态以及诊断人体运动器官，始终应以与 最佳步行速度（PWS）相等的速度进行。文献回顾表明，PWS 值在真实和虚拟环境中并不相同。本研究的目的是确定这两种环境中的 PWS 值，并确定用于根据下肢长度计算 PWS 的方程中使用的参数值。
与研究相关的测试涉及 40 名在跑步机上行走并佩戴 HMD 护目镜的受试者。空间风景使参与者感觉就像在公园散步一样。测试包括测量 COP 的位移，从而可以计算 Lyapunov 指数和 Floquet 乘数。这两个系数都用于识别不同步态速度下的稳定性。
分析表明，与没有 VR 的跑步机上的步态相比，带有 VR 的跑步机上的 PWS 较低。研究的最后阶段涉及确定新的公式系数值，以识别 VR 中舒适步态的速度。
获得的结果证明，真实和虚拟环境中的 PWS 不同。在 VR 测量中获得的数值较低。基于这些结果，重新确定了用于根据下肢长度计算 PWS 的“a”系数的值。新值可用于评估在虚拟环境中进行的跑步机步态，这在步态评估中非常重要。
