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Title: Characterizing Environmental Interactions for Soft Growing Robots
Soft, tip-extending devices, or “vine robots,” are a promising new paradigm for navigating cluttered and confined environments. Because they lengthen from their tips, there is little relative movement of the body with the environment, and the compressible nature of the device allows it to pass through orifices smaller than its diameter. However, the interaction between these devices and the environment is not well characterized. Here we present a comprehensive mathematical model that describes vine robot behavior during environmental interaction that provides a basis from which informed designs can be generated in future works. The model incorporates transverse and axial buckling modes that result from growing into obstacles with varying surface normals, as well as internal path-dependent and independent resistances to growth. Accordingly, the model is able to predict the pressure required to grow through a given environment due to the interaction forces it experiences. We experimentally validate both the individual components and the full model. Finally, we present three design insights from the model and demonstrate how they each improve performance in confined space navigation. Our work helps advance the understanding of tip-extending, vine robots through quantifying their interactions with the environment, opening the door for new designs and impactful applications in the realms of healthcare, research, search and rescue, and space exploration.  more » « less
Award ID(s):
Author(s) / Creator(s):
; ;
Date Published:
Journal Name:
IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS)
Page Range / eLocation ID:
3335 to 3342
Medium: X
Sponsoring Org:
National Science Foundation
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