John H. Hart

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A hybrid composite architecture of carbon nanotubes (CNTs), advanced fibers and a matrix is described, from CNT synthesis and characterization through to standard mechanical and electrical laminate tests. Direct growth of aligned CNTs on the surface of advanced fibers in a woven fabric enables enhancement in multifunctional laminate performance, as(More)
The solid map provides a view-independent method for solid tex-turing using an ordinary 2-D surface texture map. The solid map transforms a model's polygons into 2-D texture space without overlap. It then rasterizes the polygons in this space, interpolating the solid texture coordinates across the pixels of the polygon. These stored solid texture(More)
An interlaminar reinforcement using aligned carbon nanotubes (CNTs) is demonstrated for prepreg uni-directional carbon tape composites. Aligned CNTs are grown at high temperature and then transfer-printed to prepreg at room temperature, maintaining CNT alignment in the through-thickness direction. In initial testing, the CNT-modified interface is observed(More)
This paper presents " Magnebots " , a simple yet novel concept for overhead transportation. The system consists of vehicles with magnetic wheels that move on trackless ferromagnetic walls and ceilings, driven by on-board controllers and commanded by a central computer. Magnebots is designed to be a fundamentally simple technology that can fulfill many(More)
Advanced composites, such as those used in aerospace applications, employ a high volume fraction of aligned stiff fibers embedded in high-performance polymers. Unlike advanced composites, polymer nanocomposites (PNCs) employ low volume fraction filler-like concepts with randomly-oriented and poorly controlled morphologies due to difficult issues such as(More)
It is well-known that carbon nanotube (CNT) growth from a dense arrangement of catalyst nanoparticles creates a vertically aligned CNT forest. CNT forests offer attractive anisotropic mechanical, thermal, and electrical properties, and their anisotropic structure is enabled by the self-organization of a large number of CNTs. This process is governed by(More)
Dense millimeter-tall carpets of vertically aligned carbon nanotubes (VACNTs) were grown using thermal chemical vapor deposition (CVD) from ethylene and hydrogen gases with two or three independently controlled hot zones while introducing controlled flows of oxygen. Through preheating, oxygen and hydrogen reacted through a multi-step reaction to form water,(More)
We demonstrate the fabrication and integration of active micro-structures based on composites of 3D carbon nanotube (CNT) frameworks and hydrogels. The alignment of the CNTs within the microstructures converts the isotropic expansion of the gel into a directed anisotropic motion. Actuation by a moisture-responsive gel is observed by changing the ambient(More)