Fig. 6: A hierarchically encrypted, optically interactive walking robot for maze escape.

a Schematic illustration of the walking robot’s hierarchical design, including encryption, hologram, and actuation modules. b Schematic illustration of the maze escape process according to the four decrypted command messages. c Transition of the flower structure from a closed to an open state under water mist, revealing the underlying hologram module. Scale bars: 5 mm. d The extraction of four holographic commands by a supercontinuum laser ii), which correspond uniquely to the fluorescence emission from each of the four petals under 980 nm laser irradiation i). e Walking trajectories and escape results corresponding to four color-coded instructions under various reading sequences. f Locomotion of the walking robot driven by a 488 nm laser. Scale bars: 5 mm. g Lateral displacement of a leg along the x-axis as a function of the number of laser exposures. h Trajectories for the four movement direction scenarios with the continuous on/off operation of the laser. i Digital photos of the walking robot escaping the maze based on the specific path-guiding instructions (insets). Scale bars: 2 cm