Three-Dimensional Large Deformation of a Compliant Beam Designed for a Flexonic Mobile Node

This paper presents design and analysis of a flexonic mobile node (FMN) for structural health monitoring. Unlike rigid configurations with a fixed distance between the front and rear axles, this FMN features various deformable configurations in three-dimensional (3D) space by incorporating a compliant beam (connecting the front and rear axles with a controlled pin joint). Hence, this FMN has more flexibility to negotiate corners and attach sensors on ferromagnetic structures. These functions are facilitated by the guidance of an embedded vision controlled system. Controlling a continuous compliant beam is a challenging task in terms of nonlinear deformation with infinite degrees of kinematic redundancy. Detailed discussion focuses on a theoretical beam model for simulating its 3D deformed shape. Results include the relations between input/output displacements and rotation angle for control implementation in sensor attachment and corner negotiation. Experiment is provided for model validation by comparing with the analysis for sensor attachment.