Fig. 6
From: Joints with angle dependent damping can help to reduce impact forces in robots
Experimental results: (A) Mean and standard deviation of the ground reaction force and joint angle measured during a drop test (shown for drop height = 80 cm and 3 mm constant damper). The initial peak (1) occurs due to the inertial effect of the tip contact dynamics while the remainders (2 and 3) corresponds to the spring and damper dynamics of the passive joint. The two regions are separated by a vertical dotted line as shown in zoomed section (a). Snapshots corresponding to different time points are shown: \(t=\)401ms corresponds to the (1) peak. \(t=\)414ms corresponds to the (2) peak. \(t=\)492ms corresponds to the (3) peak. (B) Ground reaction force variation over time in the region of joint dynamics for constant dampers (CD) and variable dampers (VD) for the drop height 80 cm. The plot shows the time interval in which the damper and spring are actively involved.
