Fig. 14
![Fig. 14](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40648-016-0046-2/MediaObjects/40648_2016_46_Fig14_HTML.gif)
Time response of the resultant force in the case of foothold collapse. When the foothold of leg \(L_1\) collapses, the ground reaction becomes zero, as shown with the black circle. Conversely, the normal reactions of the other legs are still less than \(R_\mathrm{{ref}}\) after the collapse, except for the impulse as shown with the blue circle. The method of representation is the same as in Fig. 11