Fig. 4: Autonomous mechanical actuation.
From: Autonomous self-healing organic crystals for nonlinear optics
a Schematic representation of angular actuation motion in the fractured crystals. b, d Optical images showing angular motion upon fracture of the crystals captured under a high-speed camera. c The crack closure mechanism described using an angular model where θ1 – θ2 is the angular displacement. e Angular motion traced by the center of mass of the actuating crystal of radius, r, and angular displacement, θ. f Schematic representation of linear actuation motion in the fractured crystals separated over a distance, d. g Linear motion of fractured crystals, captured under a high-speed camera where the distance closes as the actuating piece moves nearer.
