Fig. 12
![Fig. 12](http://media.springernature.com/full/springer-static/image/art%3A10.1186%2Fs40648-016-0046-2/MediaObjects/40648_2016_46_Fig12_HTML.gif)
Time response of the resultant force of the experiment on the irregular slope. Each leg applies normal reaction over \(R_\mathrm{{ref}}\) in the leg-grope movement as marked with the black circles. Aside from that, each normal reaction is less than \(R_\mathrm{{ref}}\). The method of representation is the same as in Fig. 11