skdh.gait_old.StrideLength#

class skdh.gait_old.StrideLength#

The distance traveled during a stride (heel-strike to current foot heel-strike). A basic asymmetry measure is also computed as the difference between sequential stride lengths of opposite feet.

Methods

predict(fs, leg_length, gait, gait_aux)

Predict the gait event-level endpoint

Notes

The stride length is computed using the inverted pendulum model from [1] per

\[L_{step} = 2\sqrt{2l_{leg}h-h^2}\]
\[L_{stride} = L_{step, i} + L_{step, i+1}\]

where \(L_{s}\) is the step or stride length, \(l_{leg}\) is the leg length, and \(h\) is the Center of Mass change in height during a step. Leg length can either be measured, or taken to be \(0.53height\).

References

[1]

W. Zijlstra and A. L. Hof, “Assessment of spatio-temporal gait parameters from trunk accelerations during human walking,” Gait & Posture, vol. 18, no. 2, pp. 1–10, Oct. 2003, doi: 10.1016/S0966-6362(02)00190-X.