Composite Living Hinges for Robotic Applications
Abstract
This report investigates a lightweight, continuous-fiber composite hinge structure employing dual matrix materials for tailorable bending stiffness with intended application for exoskeletons and robotics. Functionality of the dual matrix structure allows for tailored load transfer across the hinge by restricting torsion and in-plane bending while allowing for localized out-of-plane bending. Classical Laminate Theory was applied for design analysis to optimize directional stiffnesses. The composite layup consists of layers of continuous woven fabric with alternating regions of epoxy and flexible polyurethane (PU) film and additional layers of woven carbon fabric in the epoxy sections to increase stiffness. A two-stage fabrication process first bonds the PU film with the flexible fabric of the hinge section followed by vacuum infusion of epoxy resin into the remaining dry fabric layers. Various hinge materials, layups, and geometries were investigated using low-cycle, high-deformation bending and torsion tests. Carbon fabric exhibited greater damage than Kevlar in the PU hinge section, both demonstrating a decrease in bending and torsion stiffness after the first test cycle. The remainder of the test cycles had a relatively constant bending and torsion stiffness. Bending and torsional stiffness of the hinge section was tailored through composite design, and a potential robotic application was investigated.
Document Details
- Document Type
- Technical Report
- Publication Date
- Sep 01, 2020
- Accession Number
- AD1109531
Entities
People
- Colin Rowbottom
- Daniel M . Baechle
- Lauren A. Moore
Organizations
- United States Army