title: A novel growing device inspired by plant root soil penetration behaviors.
abstract: Moving in an unstructured environment such as soil requires approaches that are constrained by the physics of this complex medium and can ensure energy efficiency and minimize friction while exploring and searching. Among living organisms, plants are the most efficient at soil exploration, and their roots show remarkable abilities that can be exploited in artificial systems. Energy efficiency and friction reduction are assured by a growth process wherein new cells are added at the root apex by mitosis while mature cells of the root remain stationary and in contact with the soil. We propose a new concept of root-like growing robots that is inspired by these plant root features. The device penetrates soil and develops its own structure using an additive layering technique: each layer of new material is deposited adjacent to the tip of the device. This deposition produces both a motive force at the tip and a hollow tubular structure that extends to the surface of the soil and is strongly anchored to the soil. The addition of material at the tip area facilitates soil penetration by omitting peripheral friction and thus decreasing the energy consumption down to 70% comparing with penetration by pushing into the soil from the base of the penetration system. The tubular structure provides a path for delivering materials and energy to the tip of the system and for collecting information for exploratory tasks.
authors.affiliation: Center for Micro-BioRobotics, Istituto Italiano di Tecnologia, Pontedera, Italy.
authors.forename: Ali
authors.initials: A
authors.lastname: Sadeghi
authors.affiliation: Center for Micro-BioRobotics, Istituto Italiano di Tecnologia, Pontedera, Italy ; The BioRobotics Institute, Scuola Superiore Sant'Anna, Pontedera, Italy.
authors.forename: Alice
authors.initials: A
authors.lastname: Tonazzini
authors.affiliation: Center for Micro-BioRobotics, Istituto Italiano di Tecnologia, Pontedera, Italy ; The BioRobotics Institute, Scuola Superiore Sant'Anna, Pontedera, Italy.
authors.forename: Liyana
authors.initials: L
authors.lastname: Popova
authors.affiliation: Center for Micro-BioRobotics, Istituto Italiano di Tecnologia, Pontedera, Italy.
authors.forename: Barbara
authors.initials: B
authors.lastname: Mazzolai
mesh_terms: D032701:Biomimetics / Q000295:instrumentation*; D009068:Movement; D018517:Plant Roots / Q000502:physiology*; D015203:Reproducibility of Results; D012987:Soil
chemical_list: D012987:Soil