Fig. 3

Progression of minimum plantarflexion and knee angle at heel strike for simulation szenarios. Increasing levels of velocity feedback gain (orange), muscle weakness (light blue), and velocity feedback gain + muscle weakness (purple) with simulation iteration \(\omega =0\%\) to \(\omega = 100\%\) and linear fits. a) minimum plantarflexion and b) knee angle at heel strike are shown with significant spearman correlation coefficients. Asterisks indicate significant levels of: \(^{**}\): \(p<0.0056\), and \(^{***}\): \(p<0.001\). For \(\omega _h=100\%\) and \(\omega _{hw}>60\%\) optimization led to no stable walking simulations