Figure 5
From: Simulation-based biomechanical assessment of unpowered exoskeletons for running
Other muscles’ forces. (a–e) Sub-figures show the effects of exoskeleton augmentation on the main muscles’ forces and their average over the whole stride except for the main hip muscles. The start of the gait cycle is at the heel-strike instant of the right leg, and all of the figures are for the right leg. The swing phase is shown with a dashed line over the horizontal axes. The background color code for all of the sub-figures is: white means no special effect, light gray means muscle force reduction, and dark gray means muscle force increment. As can be seen, the force of Soleus and Vastus Laterialis have no significant changes by exoskeleton augmentation. Besides, despite the significant changes in the Bicep Femoris force profile, the average force of this muscle shows no significant change in different spring coefficients; minimum on \(\alpha =0.6\) with \(2\%\) reduction. In addition, the optimum spring coefficient for Gastrocnemius Medialis and Tibialis Anterior is on \(\alpha =0\). And, the minimum average force for Vastus Lateralis and Soleus is on \(\alpha =1.5\) with \(5.6\%\) and \(1.2\%\) reductions compared to no exoskeleton case. Moreover, the average forces of these muscles have \(3.8\%\) and \(0.5\%\) reductions on \(\alpha ^*=0.6\), respectively. N \(=7\); bars, mean; error bars, s.e.m; P values, ANOVA (random effect: participant; fixed effects: spring coefficient; significance level \(=0.05\)). (f) shows the placement of the nine main branches of the muscles in the lower limb.
