• Mechanics of fibrous assemblies
• Electro-Textiles (Fiber/Textile based electrical devices)
• Electroactive polymer-based devices  
• Design and analysis of technical textiles
• Dynamics of textile processes
• Technology of fabric formation in particular, weaving technology

Examples of Current Research Projects:

High-speed unwinding of packages: The dynamics of high speed movement of yarns to and from packages, common to many textile processes, is being studied. In unwinding the yarn rotates around the axis of a stationary helically wound package. The inertial forces tend to create an envelope called a balloon. The shape and size of the balloon is substantially influenced by air drag and generates a tension distribution along the thread line that is critical to the processes. Using principles of analytical mechanics these processes have been modeled and the results reveal highly non-linear and unstable nature of these processes.

Functionally Tailored Textiles: 3-D Structures Through Melt Blown Technology: The research is aimed at developing appropriate technology necessary to produce three-dimensional molded garments to produce low cost combat uniforms with effective barrier characteristics, using minimal joining. The system being developed is called Robotic Fiber Assembly and Control (RFAC) system. RFAC system will allow incorporation of fibers, powders, or other appropriate additives into the garment systems. The additives may identify, measure, absorb, and/or deactivate chemical/biological agents. In the RFAC system deposition of meltblown fibers on an appropriate mold is controlled by a six axis industrial robot. The system allows precise control of fiber orientation distribution, fiber diameter distributions and pore size distribution.

Woven Fabric-based Electrical Circuits (Electro-textiles):   Fabric-based electrical circuits are fundamental to electrotextile products of the future. The objective of the current research is to develop fabric-based electrical circuits by interlacing conducting and non-conducting threads into woven textile structures for civilian as well as military applications. Wired interconnections between different devices attached to the conducting elements of these circuits are made by weaving conductive threads so that they follow desired electrical circuit designs. In a woven electrically conductive network, routing of electrical signals is achieved by the formation of effective electrical interconnects and disconnects. Resistance welding is identified as one of the most effective means of producing crossover point interconnects and disconnects.  These circuits are evaluated for signal integrity issues (crosstalk, etc.). Two new thread structures - coaxial and twisted Pair copper threads to minimize cross talk have been developed and evaluated. Significant reductions in crosstalk were obtained with the coaxial and twisted pair thread structures when compared with bare copper thread or insulated conductive threads.

Development of Layered Functional Fiber based Micro-Tubes: Microtubes are very small diameter functional tubes with high aspect ratio that can be made of almost any material. Specific functions performed by microtubes may include encapsulation, heat exchange, reinforcement, detection, filtration, optical waveguide, sensing, etc. The goal of this ongoing research is to explore the fundamental technological potential of fabrication of microtubes from dielectric elastomers, a class of elctroactive polymers, substantially in the form of textile fibers for applications in sensing and actuation. The long-term objective is to develop various fiber-based functional systems at various scales (micro to large). In its simplest form a dielectric elastomer actuator is a low modulus polymer film sandwiched between compliant electrodes.When a voltage is applied across the compliant electrodes the charges on the electrodes generate a compressional as well as planar deformation of the film.
To examine a number of microtube actuator concepts we are exploring various layered tubular configurations of dielectric materials and conductive electrode materials. We have evaluated silicone (Dow Corning SYLGARD 186), polyacrylate (3M^TM VHB^TM 4910), polyurethane (Deerfield's PT 6100 film), and polyolefin (DuPont's Engage) elastomers as dielectric polymers.
To develop the required compliant electrodes we have been working with graphite particles embedded in various structures, carbon fibers, and polypyrrole (using in-situ polymerization).

Electroactive Nanostructured Polymers as Tunable Actuators:
Lightweight and conformable electroactive actuators stimulated by acceptably low electric fields are required for emergent technologies such as microrobotics, flat-panel speakers, micro air vehicles and responsive prosthetics.1,2 High actuation strains (>50%) are currently afforded by dielectric elastomers at relatively high electric fields (>50 V/µm). In this work, we have developed a nanostructured copolymer blend that yields a physically cross-linked micellar networks and exhibit excellent displacement under an external electric field. Such property development reflects reductions in matrix viscosity and nanostructural order, accompanied by enhanced response of highly polarizable groups to the applied electric field. These synergistic property changes result in ultrahigh areal actuation strains (>200%) at significantly reduced electric fields (<40 V/µm). Use of nanostructured polymers whose properties can be broadly tailored by varying copolymer characteristics or blend composition represents an innovative and tunable avenue to reduced-field actuation for advanced engineering, biomimetic and biomedical applications.

Ph.D. , Fiber and Polymer Science , 1987
> North Carolina State University
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>M.S. , Textile Materials and Management , 1984
> North Carolina State University
>
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Tushar K. Ghosh, Professor, College of Textiles, North Carolina State University, holds a doctorate degree in Fiber and Polymer Science. His research interests include technology of yarn and fabric formation, mechanics of fiber assemblies, and characterization of fibrous materials. Prof. Ghosh has been active in research and educational programs on application of fibers and textiles in well specified technical or functional usage (known as Technical Textiles, e.g. geotextiles, electrotextiles, automotive airbags, etc.) His current research activities include analytical and computer modeling as well as mechanical characterization of fibrous structures, textile-based electrical devices/systems, and electroactive polymer-based actuators.

Professor Ghosh has been teaching various technology courses at both graduate and undergraduate levels.In recent years he has taught courses on weaving technology, functional textiles, and characterization of textile materials. Dr. Ghosh has served as consultant to many public institutions and industries on issues related to textile technology and performance of textile materials. He has published and presented more than one hundred scientific and technical papers in peer reviewed journals and conferences