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Soft growing robots, commonly referred to as vine robots, have demonstrated a remarkable ability to interact safely and robustly with unstructured and dynamic environments. It is therefore natural to exploit contact with the environment for planning and design optimization tasks. Previous research has focused on planning under contact for passively deforming robots with preformed bends. However, adding active steering to these soft growing robots is necessary for successful navigation in more complex environments. To this end, we develop a unified modeling framework that integrates vine robot growth, bending, actuation, and obstacle contact. We extend the beam moment model to include the effects of actuation on kinematics under growth and then use these models to develop a fast parallel simulation framework. We validate our model and simulator with real robot experiments. To showcase the capabilities of our framework, we apply our model in a design optimization task to find designs for vine robots navigating through cluttered environments, identifying designs that minimize the number of required actuators by exploiting environmental contacts. We show the robustness of the designs to environmental and manufacturing uncertainties. Finally, we fabricate an optimized design and successfully deploy it in an obstacle-rich environment. 

Soft robots excel in adaptability, and rigid robots in precise, forceful actuation, yet each faces limitations that reduce performance in cluttered or constrained settings. We address these gaps by enabling physical coupling between a soft Vine robot and centimeter-scale RESCUE roller robots, allowing heterogeneous teams to work cooperatively to leverage each other’s strengths. Our approach improves mobility, enables power sharing, and communication through mechanical interfaces, modular chain formation, and high-speed recharging and data transfer via electrical contact using magnetic connectors. RESCUE rollers can form chains for collaborative locomotion and load distribution, and seamlessly integrate with the Vine robot to extend its workspace. In return, the Vine robot serves as a mobile power and communication hub, recharging rollers and relaying data to extend operational time. Experimental validation includes measurements of pushing and pulling strength in roller chains (Section III-A), Vine robot buckling under load (Section III-B), and demonstrations of Vine robot and RESCUE rollers interactions in a cluttered environment (Section IV-A), tight turning of the Vine robot using rollers (Section IV-B), and in-field recharging of RESCUE rollers (Section IV-C). This work advances cooperative strategies for heterogeneous robotic systems, enabling adaptable and resilient performance in challenging environments. 

Nonsymmetrical oxygen-bridged binuclear copper centers have been proposed and modeled as intermediates and transition states in several C─H oxidation pathways, leading to the postulation that structural dissymmetry enhances the reactivity of the bridging oxygen. However, experimentally characterizing the structure and reactivity of these transient species is remarkably challenging. Here, we report the high-pressure synthesis of a metastable nonsymmetrical dicopper-μ-oxo compound with exceptional reactivity toward the mono-oxygenation of aliphatic C─H bonds. The nonequivalent coordination environment of copper stabilizes localized mixed valency and greatly enhances the hydrogen atom abstraction activity of the bridging oxygen, enabling room-temperature hydroxylation of methane under pressure. These findings highlight the role of dissymmetry in the reactivity of binuclear copper centers and demonstrate precise control of molecular structures by mechanical means.