RT Journal Article SR Electronic T1 A soft robot that navigates its environment through growth JF Science Robotics JO Sci. Robotics FD American Association for the Advancement of Science SP eaan3028 DO 10.1126/scirobotics.aan3028 VO 2 IS 8 A1 Hawkes, Elliot W. A1 Blumenschein, Laura H. A1 Greer, Joseph D. A1 Okamura, Allison M. YR 2017 UL http://robotics.sciencemag.org/content/2/8/eaan3028.abstract AB Across kingdoms and length scales, certain cells and organisms navigate their environments not through locomotion but through growth. This pattern of movement is found in fungal hyphae, developing neurons, and trailing plants, and is characterized by extension from the tip of the body, length change of hundreds of percent, and active control of growth direction. This results in the abilities to move through tightly constrained environments and form useful three-dimensional structures from the body. We report a class of soft pneumatic robot that is capable of a basic form of this behavior, growing substantially in length from the tip while actively controlling direction using onboard sensing of environmental stimuli; further, the peak rate of lengthening is comparable to rates of animal and robot locomotion. This is enabled by two principles: Pressurization of an inverted thin-walled vessel allows rapid and substantial lengthening of the tip of the robot body, and controlled asymmetric lengthening of the tip allows directional control. Further, we demonstrate the abilities to lengthen through constrained environments by exploiting passive deformations and form three-dimensional structures by lengthening the body of the robot along a path. Our study helps lay the foundation for engineered systems that grow to navigate the environment.