Fig. 7: Metatruss Design Variations and Performances.

a Three target positions for a morphing helmet in two objectives, with green indicating the key joints, and red being the corresponding target positions. b Joint weights of the morphing helmet are indicated by color shading, with darker shades representing larger weights. c The shape of the helmet before and after morphing. d, e Shape-shifting helmet training metrics: hypervolume and mean square distance between the key joints and the corresponding target positions. f Lobster robot’s walking trajectory and morphologies at different times. g–i Lobster robot metrics: hypervolume, energy efficiency, and walking distance. j Tentacle robot reaching three distinct target positions. k, l Tentacle robot metrics: hypervolume and mean squared distance between the tracking joint and three target positions.