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Erdman, III, Donald

Publications and source records attributed to Erdman, III, Donald.

Printed Strain Gauges for Anthropomorphic Test Dummies for Vehicle Crash Testing

In Phase 1 of the technical collaboration between Oak Ridge National Laboratory (ORNL) and Humanetics, additive manufacturing was studied as a method to produce high strain – strain gauges that are embedded in an additively manufactured (AM) anthropomorphic crash test dummy (ATD) to provide high fidelity data to significantly improve vehicle safety. In this study commercially available conductive filament was acquired and the mechanical properties were tested for use in this application. The design space of embedded printed strain gauges was explored with multiple configurations printed and tested for performance. The testing resulted in finding that commercially available filament materials were unable to meet the performance requirements. Finally, an extensive literature survey was performed on advanced manufacturing techniques and novel high strain conductive materials to manufacture strain gauges that can be embedded in to the AM ATD. Humanetics have taken the literature survey and have reached out to material suppliers such as Techmer to provide custom blends of materials for testing. Humanetics will continue to build off of the research that was performed and test custom materials for use in AM ATDs.

36 MATERIALS SCIENCE↗

Fabric properties and electric efficiency limits of mechanical moisture extraction from fabrics

Residential clothes drying consume about 650 TBtu of primary energy per year in the United States, equivalent to 3% of primary residential energy consumption. There is a strong impetus to reduce the energy consumption of clothes dryers by both improving existing technology and developing alternatives that use fundamentally different drying mechanisms. Clothes drying technologies are broadly classified into either evaporative or mechanical drying. The focus of this paper is on mechanical drying, including vibrational, centrifugal, and press-based methods. In this work, the physical processes involved in these mechanical fabric drying processes were analyzed to develop general theories of mechanical cloth drying energy efficiency. Quantitative evaluation of the theories requires measured fabric properties. To accomplish this, a set of experiments was conducted on samples of a standard test fabric. The fabric was a cotton-polyester blend specified by the US Department of Energy to evaluate the standardized efficiency of all residential clothes dryers in the US. Mercury porosimetry experiments were conducted to determine the fabric pore size distribution, apparent density, and porosity. Elasticity experiments were conducted to determine the fabric’s Young’s modulus. Isostatic press experiments were conducted to establish a relationship between compression force and fabric moisture content. The data resulting from these experiments were combined with mathematical models developed in this work to calculate the theoretical maximum performance limits for mechanical drying of the standard fabric. The results of the analysis are used to make recommendations for the most promising technologies that offer the greatest potential energy savings for residential clothes drying.

36 MATERIALS SCIENCE↗