Fig. 8. Estimation of peak spring force and maximum spring compression in the case of a disturbed contact (15 cm step up) with a varied angle of attack and spring stiffness for a spring–mass simulation. The dotted lines indicate spring forces between 1.5 and 3 times gravitational force and the black lines indicate spring compressions between 0.1 and 0.15 times initial leg length. The arrows highlight the small areas of experimentally measured values. (A) In the simulation, decreasing spring stiffness and steepening angle of attack led to a decreasing peak spring force. (B) However, an increasing maximum spring compression with increasing spring stiffness can only be realized by substantially flattening the angle of attack. Initial conditions on ground level were _x,0=4.5 m s^–1, y₀=0.95 m, m=80 kg, l₀=1 m, and were altered in the consecutive contact due to the step.