Thomas J. Pence

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A finite strain model for the mechanical degradation of composite materials with multiple families of fine reinforcing fibers is developed and studied. At any instant of time the matrix material may or may not be degrading with all, some, or none of the interpenetrating fibers also undergoing degradation. This multi-component description of damage is(More)
Conjugated polymers are promising actuation materials for biomimetic robots and biomedical devices. Large bending is involved in some of these applications. This poses significant challenges in electromechanical modeling, because the linear elasticity theory is only valid when the strain is small. In this paper an effective strategy based on the nonlinear(More)
Some recent analyses modeled the response of collagenous tissues, such as epicardium, using a hypothetical network consisting of interconnected springlike fibers. The fibers in the network were organized such that internal nodes served as the connection point between three such collagen springs. The results for assumed affine and nonaffine deformations are(More)
Existing conjugated-polymer actuators typically take the form of benders or linear extenders. In this paper, a conjugatedpolymer-based torsional actuator is proposed by embedding helically wound fibers into a conjugated polymer tube during the polymer-deposition process. Upon actuation, the electrolyte-soaked tube swells, and consequently, produces torsion(More)
Angioedema, the rapid swelling of under-skin tissue, is typically triggered by complex biochemical processes that disrupt an original steady state filtration of liquid through the tissue. Swelling stabilizes once a new steady state is achieved in which the tissue has significantly increased liquid content. These processes are controlled by events at the(More)
Models for shape memory material behaviour can be posed in the framework of a structured continuum theory. We study such a framework in which a scalar phase fraction field and a tensor field of martensite reorientation describe the material microstructure, in the context of finite strains. Gradients of the microstructural descriptors naturally enter the(More)
Reported conjugated polymer actuators have typically been limited to bender or linear extender configurations. In this paper, we present a fiber-reinforced conjugated polymer actuator capable of torsional motion. By incorporating platinum fibers into the material matrix during the electrochemical fabrication process, we create anisotropy in the interaction(More)
Angioedema is a tissue-swelling pathology due to rapid change in soft tissue fluid content. Its occurrence in the trachea is predominantly localized to the soft mucous tissue that forms the innermost tracheal layer. The biomechanical consequences, such as airway constriction, are dependent upon the ensuing mechanical interactions between all of the various(More)
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