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Del Dottore E, Mondini A, Rowe N, Mazzolai B. A growing soft robot with climbing plant-inspired adaptive behaviors for navigation in unstructured environments. Sci Robot 2024; 9:eadi5908. [PMID: 38232147 DOI: 10.1126/scirobotics.adi5908] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2023] [Accepted: 12/14/2023] [Indexed: 01/19/2024]
Abstract
Self-growing robots are an emerging solution in soft robotics for navigating, exploring, and colonizing unstructured environments. However, their ability to grow and move in heterogeneous three-dimensional (3D) spaces, comparable with real-world conditions, is still developing. We present an autonomous growing robot that draws inspiration from the behavioral adaptive strategies of climbing plants to navigate unstructured environments. The robot mimics climbing plants' apical shoot to sense and coordinate additive adaptive growth via an embedded additive manufacturing mechanism and a sensorized tip. Growth orientation, comparable with tropisms in real plants, is dictated by external stimuli, including gravity, light, and shade. These are incorporated within a vector field method to implement the preferred adaptive behavior for a given environment and task, such as growth toward light and/or against gravity. We demonstrate the robot's ability to navigate through growth in relation to voids, potential supports, and thoroughfares in otherwise complex habitats. Adaptive twining around vertical supports can provide an escape from mechanical stress due to self-support, reduce energy expenditure for construction costs, and develop an anchorage point to support further growth and crossing gaps. The robot adapts its material printing parameters to develop a light body and fast growth to twine on supports or a tougher body to enable self-support and cross gaps. These features, typical of climbing plants, highlight a potential for adaptive robots and their on-demand manufacturing. They are especially promising for applications in exploring, monitoring, and interacting with unstructured environments or in the autonomous construction of complex infrastructures.
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Affiliation(s)
- Emanuela Del Dottore
- Bioinspired Soft Robotics Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
| | - Alessio Mondini
- Bioinspired Soft Robotics Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
| | - Nick Rowe
- AMAP Laboratory, University of Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, France
| | - Barbara Mazzolai
- Bioinspired Soft Robotics Laboratory, Fondazione Istituto Italiano di Tecnologia, Genova, Italy
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Rowe NP, Cheng Clavel L, Soffiatti P. Failure without Tears: Two-Step Attachment in a Climbing Cactus. Biomimetics (Basel) 2023; 8:220. [PMID: 37366815 DOI: 10.3390/biomimetics8020220] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2023] [Revised: 05/09/2023] [Accepted: 05/20/2023] [Indexed: 06/28/2023] Open
Abstract
Climbing plants can be extremely adaptable to diverse habitats and capable of colonising perturbed, unstructured, and even moving environments. The timing of the attachment process, whether instantaneous (e.g., a pre-formed hook) or slow (growth process), crucially depends on the environmental context and the evolutionary history of the group concerned. We observed how spines and adhesive roots develop and tested their mechanical strength in the climbing cactus Selenicereus setaceus (Cactaceae) in its natural habitat. Spines are formed on the edges of the triangular cross-section of the climbing stem and originate in soft axillary buds (areoles). Roots are formed in the inner hard core of the stem (wood cylinder) and grow via tunnelling through soft tissue, emerging from the outer skin. We measured maximal spine strength and root strength via simple tensile tests using a field measuring Instron device. Spine and root strengths differ, and this has a biological significance for the support of the stem. Our measurements indicate that the measured mean strength of a single spine could theoretically support an average force of 2.8 N. This corresponds to an equivalent stem length of 2.62 m (mass of 285 g). The measured mean strength of root could theoretically support an average of 13.71 N. This corresponds to a stem length of 12.91 m (mass of 1398 g). We introduce the notion of two-step attachment in climbing plants. In this cactus, the first step deploys hooks that attach to a substrate; this process is instantaneous and is highly adapted for moving environments. The second step involves more solid root attachment to the substrate involving slower growth processes. We discuss how initial fast hook attachment can steady the plant on supports allowing for the slower root attachment. This is likely to be important in wind-prone and moving environmental conditions. We also explore how two-step anchoring mechanisms are of interest for technical applications, particularly for soft-bodied artefacts, which must safely deploy hard and stiff materials originating from a soft compliant body.
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Affiliation(s)
- Nick P Rowe
- AMAP, University of Montpellier, CIRAD, CNRS, INRAE, IRD, 34398 Montpellier, France
| | - Lily Cheng Clavel
- AMAP, University of Montpellier, CIRAD, CNRS, INRAE, IRD, 34398 Montpellier, France
| | - Patricia Soffiatti
- Department of Botany, Federal University of Parana State (UFPR), Curitiba CEP81531-990, Brazil
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Meder F, Baytekin B, Del Dottore E, Meroz Y, Tauber F, Walker I, Mazzolai B. A perspective on plant robotics: from bioinspiration to hybrid systems. BIOINSPIRATION & BIOMIMETICS 2022; 18:015006. [PMID: 36351300 DOI: 10.1088/1748-3190/aca198] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/13/2022] [Accepted: 11/09/2022] [Indexed: 06/16/2023]
Abstract
As miscellaneous as the Plant Kingdom is, correspondingly diverse are the opportunities for taking inspiration from plants for innovations in science and engineering. Especially in robotics, properties like growth, adaptation to environments, ingenious materials, sustainability, and energy-effectiveness of plants provide an extremely rich source of inspiration to develop new technologies-and many of them are still in the beginning of being discovered. In the last decade, researchers have begun to reproduce complex plant functions leading to functionality that goes far beyond conventional robotics and this includes sustainability, resource saving, and eco-friendliness. This perspective drawn by specialists in different related disciplines provides a snapshot from the last decade of research in the field and draws conclusions on the current challenges, unanswered questions on plant functions, plant-inspired robots, bioinspired materials, and plant-hybrid systems looking ahead to the future of these research fields.
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Affiliation(s)
- Fabian Meder
- Bioinspired Soft Robotics, Istituto Italiano di Tecnologia, Genoa, Italy
| | - Bilge Baytekin
- Department of Chemistry and UNAM National Nanotechnology Research Center, Bilkent University, Ankara, Turkey
| | | | - Yasmine Meroz
- School of Plant Sciences and Food Security, Tel Aviv University, Tel Aviv, Israel
| | - Falk Tauber
- Plant Biomechanics Group (PBG) Freiburg, Botanic Garden of the University of Freiburg, Freiburg, Germany
- Cluster of Excellence livMatS @ FIT-Freiburg Center for Interactive Materials and Bioinspired Technologies, University of Freiburg, Freiburg, Germany
| | - Ian Walker
- Department of Electrical and Computer Engineering, Clemson University, Clemson, SC, United States of America
| | - Barbara Mazzolai
- Bioinspired Soft Robotics, Istituto Italiano di Tecnologia, Genoa, Italy
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Louf JF, Alexander SLM. Poroelastic plant-inspired structures & materials to sense, regulate flow, and move. BIOINSPIRATION & BIOMIMETICS 2022; 18:015002. [PMID: 36317663 DOI: 10.1088/1748-3190/ac9e32] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2022] [Accepted: 10/27/2022] [Indexed: 06/16/2023]
Abstract
Despite their lack of a nervous system and muscles, plants are able to feel, regulate flow, and move. Such abilities are achieved through complex multi-scale couplings between biology, chemistry, and physics, making them difficult to decipher. A promising approach is to decompose plant responses in different blocks that can be modeled independently, and combined later on for a more holistic view. In this perspective, we examine the most recent strategies for designing plant-inspired soft devices that leverage poroelastic principles to sense, manipulate flow, and even generate motion. We will start at the organism scale, and study how plants can use poroelasticity to carry informationin-lieuof a nervous system. Then, we will go down in size and look at how plants manage to passively regulate flow at the microscopic scale using valves with encoded geometric non-linearities. Lastly, we will see at an even smaller scale, at the nanoscopic scale, how fibers orientation in plants' tissues allow them to induce motion using water instead of muscles.
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Affiliation(s)
- Jean-François Louf
- Department of Chemical Engineering, Auburn University, Auburn, AL 36849, United States of America
| | - Symone L M Alexander
- Department of Chemical Engineering, Auburn University, Auburn, AL 36849, United States of America
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Lee J, Calvo P. Enacting Plant-Inspired Robotics. Front Neurorobot 2022; 15:772012. [PMID: 35173596 PMCID: PMC8841489 DOI: 10.3389/fnbot.2021.772012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Accepted: 12/30/2021] [Indexed: 11/26/2022] Open
Abstract
Plants offer a source of bioinspiration for soft robotics. Nevertheless, a gap remains in designing robots based on the fundamental principles of plant intelligence, rooted in a non-centralized, modular architecture and a highly plastic phenotype. We contend that a holistic approach to plant bioinspiration—one that draws more fully on the features of plant intelligence and behavior—evidences the value of an enactivist perspective. This is because enactivism emphasizes not only features of embodiment such as material composition and morphology, but also autonomy as an important aspect of plant intelligence and behavior. The enactivist sense of autonomy concerns the dynamics of self-producing systems (such as plants) that create a distinction between themselves and a domain of interactions that bear on the conditions of viability of the system. This contrasts with the widespread, but diluted notion of autonomy that merely indicates the independent operability of a system for an arbitrary period. Different notions of autonomy are relevant for soft roboticists, for instance, when evaluating limitations on existing growing robots (“growbots”) that take bioinspiration from plants, but depend on a fixed source of energy and material provided by an external agent. More generally, plant-inspired robots serve as a case study for an enactivist approach to intelligence, while, correspondingly, enactivism calls attention to the possibility of non-zoological forms of intelligence embodied in a self-organizing, autonomous system.
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Monje CA, Laschi C. Editorial: Advances in Soft Robotics Based on Outputs From IROS 2018. Front Robot AI 2020; 7:124. [PMID: 33501290 PMCID: PMC7805609 DOI: 10.3389/frobt.2020.00124] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2020] [Accepted: 08/05/2020] [Indexed: 11/13/2022] Open
Affiliation(s)
- Concepción A. Monje
- Systems Engineering and Automation, Universidad Carlos III de Madrid, Leganés, Spain
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Soffiatti P, Rowe NP. Mechanical Innovations of a Climbing Cactus: Functional Insights for a New Generation of Growing Robots. Front Robot AI 2020; 7:64. [PMID: 33501232 PMCID: PMC7806016 DOI: 10.3389/frobt.2020.00064] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2019] [Accepted: 04/20/2020] [Indexed: 12/23/2022] Open
Abstract
Climbing plants are being increasingly viewed as models for bioinspired growing robots capable of spanning voids and attaching to diverse substrates. We explore the functional traits of the climbing cactus Selenicereus setaceus (Cactaceae) from the Atlantic forest of Brazil and discuss the potential of these traits for robotics applications. The plant is capable of growing through highly unstructured habitats and attaching to variable substrates including soil, leaf litter, tree surfaces, rocks, and fine branches of tree canopies in wind-blown conditions. Stems develop highly variable cross-sectional geometries at different stages of growth. They include cylindrical basal stems, triangular climbing stems and apical star-shaped stems searching for supports. Searcher stems develop relatively rigid properties for a given cross-sectional area and are capable of spanning voids of up to 1 m. Optimization of rigidity in searcher stems provide some potential design ideas for additive engineering technologies where climbing robotic artifacts must limit materials and mass for curbing bending moments and buckling while climbing and searching. A two-step attachment mechanism involves deployment of recurved, multi-angled spines that grapple on to wide ranging surfaces holding the stem in place for more solid attachment via root growth from the stem. The cactus is an instructive example of how light mass searchers with a winged profile and two step attachment strategies can facilitate traversing voids and making reliable attachment to a wide range of supports and surfaces.
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Affiliation(s)
- Patricia Soffiatti
- Department of Botany, Federal University of Parana State (UFPR), Curitiba, Brazil
| | - Nick P. Rowe
- AMAP, Univ Montpellier, CIRAD, CNRS, INRAE, IRD, Montpellier, France
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Greer JD, Blumenschein LH, Alterovitz R, Hawkes EW, Okamura AM. Robust navigation of a soft growing robot by exploiting contact with the environment. Int J Rob Res 2020. [DOI: 10.1177/0278364920903774] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
Navigation and motion control of a robot to a destination are tasks that have historically been performed with the assumption that contact with the environment is harmful. This makes sense for rigid-bodied robots, where obstacle collisions are fundamentally dangerous. However, because many soft robots have bodies that are low-inertia and compliant, obstacle contact is inherently safe. As a result, constraining paths of the robot to not interact with the environment is not necessary and may be limiting. In this article, we mathematically formalize interactions of a soft growing robot with a planar environment in an empirical kinematic model. Using this interaction model, we develop a method to plan paths for the robot to a destination. Rather than avoiding contact with the environment, the planner exploits obstacle contact when beneficial for navigation. We find that a planner that takes into account and capitalizes on environmental contact produces paths that are more robust to uncertainty than a planner that avoids all obstacle contact.
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Affiliation(s)
- Joseph D Greer
- Department of Mechanical Engineering, Stanford University, Stanford, CA, USA
| | | | - Ron Alterovitz
- Department of Computer Science, University of North Carolina at Chapel Hill, NC, USA
| | - Elliot W Hawkes
- Department of Mechanical Engineering, University of California, Santa Barbara, CA, USA
| | - Allison M Okamura
- Department of Mechanical Engineering, Stanford University, Stanford, CA, USA
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