The invention discloses a robot network structure suitable for an unstructured environment and a sensing system. The robot network structure is a basic unit or superposition of multiple basic units. An upper structure of the basic unit comprises at least two first nodes, and a lower structure comprises at least two second nodes which are not coplanar with the at least two first nodes. All the first nodes and all the second nodes form a three-dimensional network structure through connecting rods. According to the invention, when a lateral acting force from the external environment is received, the connecting rod of the three-dimensional network structure undergoes concave deformation in a space to adapt to a geometric structure of the external environment, thereby enabling a robot to realize physical interaction in the unstructured environment; and on top of this, a hollow structure of the connecting rod may be directly used as an optical path or a single or multiple optical fiber loops may be embedded therein, and the physical deformation of the connecting rod is detected by measuring the change of light flux, so that the robot may realize the physical perception of the unstructured environment during interaction.