Hydraulic Eversion in Confined Cellular Water Structures: Mechanics of an Infrastructure-Building Maintenance Agent

We present the first mechanics framework for hydraulic eversion in a water-filled confined environment, in which a vine-robot descendant grows by pressure-driven eversion while simultaneously emplacing permanent structural and sensing infrastructure. The Adaptive Matrix Worm (AMW) operates inside the water-filled cellular passages of an Adaptive Matrix Ecosystem (AME) structure, navigating by eversion of a stored Natural Rubber Latex (NRL) tube driven by a small, depth-independent gauge pressure differential (ΔP = 2–10 kPa). A quasi-static force budget F_drive = F_fold + F_wall + F_pay + F_fiber + F_steer + F_pen governs growth; fold friction dominates at 70–85% of total resistance across four distinct operating modes (Cruising, Routing, Open Water, and Penetration). Depth independence follows exactly from the Pressure Differential Architecture (PDA) theorem: both eversion supply and ambient exterior pressure are hydrostatic, so gauge ΔP is invariant with depth; a mission at 1 m is mechanically identical to a mission at 100 m. The AMW is not a traveler: every mission permanently deposits NRL tubing and embedded Distributed Fiber-Optic Sensing (DFOS) fiber, extending both the circulatory and nervous systems of the living structure. Transit time is construction time. We identify four confirmed novelties absent from prior vine-robot literature, draw a principled comparison with industrial Cured-in-Place Pipe (CIPP) inversion, and provide an honest Technology Readiness Level (TRL) assessment and validation roadmap. Paper 4B completes the coordinated 4A+4B set: Paper 4A proves the matrix is collectively rigid; Paper 4B proves the maintenance agent can operate within it and grow permanent infrastructure.