Fig. 2: Design of the leg-claw appendage.
A Bistable claw configuration, before and after contact. B Photo composition of the claw in open, closed, and in-between positions. Open angle is Ψ1 and closed angle is Ψ2. The visible spring absorbs the impact. C Tendon-pulling re-opening mechanism entirely integrated within the leg tube, see a rendered section view in Supplementary Fig. 12 and modeled geometry of the inner part of the claw shown at increasing angles between the open and closed/contact positions. D Projected torques and forces on the branch. E Torque measurement of the claw with three different contact materials (Spikes, Ecoflex silicone and PLA plastic). F Leg geometry parameter definition for the modeling of the leg. G Side-view of the optimized leg assembly.
