Abstract
Designs perfected through evolution have informed bioinspired animal-like robots that mimic the locomotion of cheetahs and the compliance of jellyfish; biohybrid robots go a step further by incorporating living materials directly into engineered systems. Bioinspiration and biohybridization have led to new, exciting research, but humans have relied on biotic materials-non-living materials derived from living organisms-since their early ancestors wore animal hides as clothing and used bones for tools. In this work, an inanimate spider is repurposed as a ready-to-use actuator requiring only a single facile fabrication step, initiating the area of "necrobotics" in which biotic materials are used as robotic components. The unique walking mechanism of spiders-relying on hydraulic pressure rather than antagonistic muscle pairs to extend their legs-results in a necrobotic gripper that naturally resides in its closed state and can be opened by applying pressure. The necrobotic gripper is capable of grasping objects with irregular geometries and up to 130% of its own mass. Furthermore, the gripper can serve as a handheld device and innately camouflages in outdoor environments. Necrobotics can be further extended to incorporate biotic materials derived from other creatures with similar hydraulic mechanisms for locomotion and articulation.