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Credible, Automated Meshing of Images (CAMI)

Roberts, Scott A.; Donohoe, Brendan D.; Martinez, Carianne M.; Krygier, Michael K.; Hernandez-Sanchez, Bernadette A.; Foster, Collin W.; Collins, Lincoln; Greene, Benjamin G.; Noble, David R.; Norris, Chance A.; Potter, Kevin M.; Roberts, Christine C.; Neal, Kyle D.; Bernard, Sylvain R.; Schroeder, Benjamin B.; Trembacki, Bradley L.; LaBonte, Tyler L.; Sharma, Krish S.; Ganter, Tyler G.; Jones, Jessica E.; Smith, Matthew D.

Abstract not provided.

Remote Temperature Distribution Sensing Using Permanent Magnets

IEEE Transactions on Magnetics

Chen, Yi; Guba, Oksana G.; Brooks, Carlton F.; Roberts, Christine C.; van Bloemen Waanders, Bart G.; Nemer, Martin N.

Remote temperature sensing is essential for applications in enclosed vessels, where feedthroughs or optical access points are not possible. A unique sensing method for measuring the temperature of multiple closely spaced points is proposed using permanent magnets and several three-axis magnetic field sensors. The magnetic field theory for multiple magnets is discussed and a solution technique is presented. Experimental calibration procedures, solution inversion considerations, and methods for optimizing the magnet orientations are described in order to obtain low-noise temperature estimates. The experimental setup and the properties of permanent magnets are shown. Finally, experiments were conducted to determine the temperature of nine magnets in different configurations over a temperature range of 5 °C to 60 °C and for a sensor-to-magnet distance of up to 35 mm. To show the possible applications of this sensing system for measuring temperatures through metal walls, additional experiments were conducted inside an opaque 304 stainless steel cylinder.

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Wireless temperature sensing using permanent magnets for multiple points undergoing repeatable motions

ASME 2016 Dynamic Systems and Control Conference, DSCC 2016

Chen, Yi; Guba, Oksana G.; Brooks, Carlton F.; Roberts, Christine C.; van Bloemen Waanders, Bart G.; Nemer, Martin N.

Temperature monitoring is essential in automation, mechatronics, robotics and other dynamic systems. Wireless methods which can sense multiple temperatures at the same time without the use of cables or slip-rings can enable many new applications. A novel method utilizing small permanent magnets is presented for wirelessly measuring the temperature of multiple points moving in repeatable motions. The technique utilizes linear least squares inversion to separate the magnetic field contributions of each magnet as it changes temperature. The experimental setup and calibration methods are discussed. Initial experiments show that temperatures from 5 to 50 °C can be accurately tracked for three neodymium iron boron magnets in a stationary configuration and while traversing in arbitrary, repeatable trajectories. This work presents a new sensing capability that can be extended to tracking multiple temperatures inside opaque vessels, on rotating bearings, within batteries, or at the tip of complex endeffectors.

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Computational Mechanics for Heterogeneous Materials

Baczewski, Andrew D.; Yarrington, Cole Y.; Bond, Stephen D.; Erikson, William W.; Lehoucq, Richard B.; Mondy, L.A.; Noble, David R.; Pierce, Flint P.; Roberts, Christine C.; Van Swol, Frank

The subject of this work is the development of models for the numerical simulation of matter, momentum, and energy balance in heterogeneous materials. These are materials that consist of multiple phases or species or that are structured on some (perhaps many) scale(s). By computational mechanics we mean to refer generally to the standard type of modeling that is done at the level of macroscopic balance laws (mass, momentum, energy). We will refer to the flow or flux of these quantities in a generalized sense as transport. At issue here are the forms of the governing equations in these complex materials which are potentially strongly inhomogeneous below some correlation length scale and are yet homogeneous on larger length scales. The question then becomes one of how to model this behavior and what are the proper multi-scale equations to capture the transport mechanisms across scales. To address this we look to the area of generalized stochastic process that underlie the transport processes in homogeneous materials. The archetypal example being the relationship between a random walk or Brownian motion stochastic processes and the associated Fokker-Planck or diffusion equation. Here we are interested in how this classical setting changes when inhomogeneities or correlations in structure are introduced into the problem. Aspects of non-classical behavior need to be addressed, such as non-Fickian behavior of the mean-squared-displacement (MSD) and non-Gaussian behavior of the underlying probability distribution of jumps. We present an experimental technique and apparatus built to investigate some of these issues. We also discuss diffusive processes in inhomogeneous systems, and the role of the chemical potential in diffusion of hard spheres is considered. Also, the relevance to liquid metal solutions is considered. Finally we present an example of how inhomogeneities in material microstructure introduce fluctuations at the meso-scale for a thermal conduction problem. These fluctuations due to random microstructures also provide a means of characterizing the aleatory uncertainty in material properties at the mesoscale.

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9 Results
9 Results