A marker-based motion capture technique was used.

<p>A: Insects were labelled with reflective markers. B: For kinematic analysis, the body was modelled as a branched kinematic chain. The main body chain (left) consisted of the three thorax segments (Root, T2, T1) and the head. Six side chains (right) modelled the legs, with the segments coxa, femur and tibia (cox, fem, tib; only right legs are shown, labelled R1 to R3). All rotation axes (DoF) are indicated (3 for the root segment, 2 for thorax/head segments, and 5 per leg). DoF are denoted according to the subsequent segment and the axis of the local coordinate system around which the rotation was executed. Leg DoF were: cox.x, cox.y, cox.z (labelled for R2), fem.y and tib.y (labelled for R1). C: Two of the four conditions, with stick figures drawn every 100 ms, showing the body axis (green <i>lines</i>), the head (red <i>circle</i>s) and both front legs (black lines). <i>Left</i>: Flat walking condition without stairs. <i>Right</i>: High climbing condition with 48 mm stairs.