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Visualizing the Critical Dynamic Events of Carbon Nanocomposites
using Low Cost Wearable Virtual Reality Tools
Chad Brewer, Taylor Kuttenkuler, Brittany Porter, and Chris Klenke
Missouri State University
Advisors: Dr. Razib Iqbal and Dr. Ridwan Sakidja
Abstract
Purpose of the study is to construct Virtual Reality tools that can be used for materials
science education to educate topics related to the dynamics in nanomaterials. Researchers
used the Unity Game Engine to visualize the reactions between Carbon Nanocomposites
and Oxygen molecules. After the development of the atomistic models and the initial
development in Unity, the application is able to be installed on mobile devices that meet
the API level for Google Daydream.
Modeling Development
Our project concentrates on evaluating the effect of aggressive environments onto the structural
stability of carbon nanomaterials. As a model system, we specifically looked at the stability of
Carbon Nanotubes (CNTs) against oxidative environments at elevated temperatures. The range
of temperature that we examined was set from 1000K to 3000K. We used the molecular
dynamics simulation code developed by Sandia National Laboratory called “LAMMPS” which
stands for Large-Scale Atomic/Molecular Massively Parallel Simulator. Each time step is set to
be ¼ of a femtosecond (10-15
s). We allowed the CNT to be surrounded by oxygen molecules and
we maintained each simulation under a constant average temperature. One of the challenge in
simulating the chemical reaction is the need to have a ready reactive potential that can depict
accurately the formation and breakage of chemical bonds during chemical reactions. For Carbon
and Oxygen, REAX-FF (Reactive Force Field) developed by materials scientists Adri van Duin,
William A. Goddard, III, and co- workers at the California Institute of Technology[1-2]. We
used 10,288 atoms for each molecular dynamics (MD) simulation.
As expected, the reaction rate depends quite heavily on the temperatures. At 1000-1500K, we did
not see any disintegration of the CNTs at least with the simulation time that we used. Figure 1-4
show the atomic trajectories at the start and end of the simulations at 1500K. Figure 5-8 show the
similar trajectories but at 2500K. The disintegration at 2500K initiates at the edge of the CNS
and this is expected because of the dangling carbon bonds at the edge of each CNTs. The oxygen
molecules would create C-O bonds and over time starts to weaken the stability of the edges
before the whole CNT becomes disintegrated. During the disintegration process, CO and CO2
molecules form.
Figure 1: 1500K Time Step 1
Figure 2: 1500K Time Step 350
Figure 3: 1500K Time Step 500
Figure 4: 1500K Time Step 800
Figure 5: 2500K Time Step 1
Figure 6: 2500K Time Step 350
Figure 7: 2500K Time Step 500
Figure 8: 1500K Time Step 550
Application Development
The chemical reactions associated with the oxidation of carbon nanocomposites as shown above
and the trajectory of atoms involved in such reactions as well as the trajectories of carbon
nanocomposites under various forms of stress is often a hard concept to intuitively visualize. For
this reason, and due to the growing prevalence of nanocomposites within the sciences, a method
for visualizing these atomic processes becomes a very beneficial tool. As such, this project set
out with the notion to make visualizing various simulated atomic reactions in real-time a
possibility, utilizing new virtual reality technology and enhanced user control to allow for
researchers to gain a better idea as to the nature of such events.
We utilized the Unity Game Engine to create a visualization of the chemical reactions involving
Carbon nanocomposites. The project is a continuation of a previous project that used Google
Cardboard to view the molecular structure of statically modeled Buckminsterfullerene chemical
structures. The project was expanded to be developed for the Google Daydream device and
corresponding functionality. The upgrade from Google Cardboard to Daydream allows for more
user accessibility and interaction than the project had previously been able to achieve.
The development team was given data by their physics counterparts in the form of a text file to
be parsed by Unity and assigned to individual atoms for a virtual reality simulation. The original
data was created utilizing software available to the physics department and edited into the correct
format for the file parser. This data was intended to model the trajectories of the various atoms
involved, and had to be parsed in such a way that it were separated by frame and then by
individual atom. Each atom was then assigned a list of its overall trajectory path that would be
used to simulate the movement of the atom over the course of the entire simulation data set. The
atoms were also distinguished by their type via color so that users would be aware of the various
atoms properties.
We designed the user interface of the application to allow for frame manipulation capabilities,
such as rewinding and fast forwarding, and to allow the user to halt the simulation and go back
and forth between frames as desired. This allows for users to easily study the simulated chemical
interactions. Due to the bluetooth controller that comes partnered with the Daydream, the user is
able to manipulate the scene which they are viewing in a much more impactful way, and is now
able to move about the scene to get a better view of the chemical reactions taking place. Given
the enhanced user controls, the user is able to utilize the program to study a given simulation in a
much more productive manner, both due to addition of movement, and due to the ability to
manipulate the playback of the simulation as desired.
A method was also implemented that allows the user to choose which data set to visualize. This
is accomplished by retrieving the text files, containing the trajectory data to be visualized, from a
website hosted by Missouri State University. The user interface displays a list of the simulations
that can be ran, then loads the chosen data, from the website, into the application for
visualization. More data can be added to the website so that it can be used by the application for
future simulation purposes, and so that all of the data may be consolidated within a single
location.
Summary
We have developed visualization tools to help understand the dynamics in nanomaterials under
aggressive environments. This technology can potentially be used as an effective tool for
physics/materials science courses.
Acknowledgements
We would like to thank NASA and MOSGC for funding the project.
Biographies
Chad Brewer is originally from Charleston, Arkansas. He is a Senior Computer Science major at
Missouri State University and also holds a BA in Sociology and an AA in Criminal Justice. Chad
is currently involved with one independent research project: Visualizing the Critical Dynamic
Events of Carbon Nanocomposites Using Low Cost Wearable Virtual Reality Tools. This project
will end with an IEEE published paper that will hopefully land him a career either involving
Virtual Reality applications or software development.
Taylor Kuttenkuler is originally from California, Missouri. He is currently a Junior Computer
Science major at Missouri State University and may possibly pursue a minor in Cybersecurity.
Taylor is currently involved with one independent research project: Visualizing the Critical
Dynamic Events of Carbon Nanocomposites Using Low Cost Wearable Virtual Reality Tools.
While not attending school, Taylor works as intern in the Information Technology Department of
the the Missouri Department of Employment Security. He is hoping to use the experience gained
from this project to further widen his knowledge of software development and his future career.
Chris Klenke is from Pacific, Missouri. He is a senior majoring in both Physics and General
Mathematics and minoring in both astronomy and computer science. Chris researches the
stability of carbon nanomaterials against aggressive environments with Dr. Ridwan Sakidja and
theoretical exoplanet atmosphere components with Dr. David Cornelison, both in the Physics,
Astronomy, and Materials Science Department at Missouri State University. Chris hopes to carry
his research forward into a doctoral program researching astrophysics after his undergraduate
studies are over.
Brittany Porter is from Kansas City, Missouri. She is a senior Sociology major with a
Mathematics minor at Missouri State University. Brittany’s current research projects include
working with Dr. Ridwan Sakidja studying the stability of carbon nanomaterials. She also studies
the intersection of Catholicism and politics with Dr. Catherine Hoegeman. Brittany is hoping to
continue her education in the social sciences in the future.
References
1. van Duin, Adri C. T.; Dasgupta, Siddharth; Lorant, Francois; Goddard, William A. (2001).
"ReaxFF: A Reactive Force Field for Hydrocarbons" (PDF). The Journal of Physical
Chemistry A. 105 (41): 9396–9409
2. Nielson, Kevin D.; van Duin, Adri C. T.; Oxgaard, Jonas; Deng, Wei-Qiao; Goddard, William
A. (2005). "Development of the ReaxFF Reactive Force Field for Describing Transition Metal
Catalyzed Reactions, with Application to the Initial Stages of the Catalytic Formation of
Carbon Nanotubes" (PDF). The Journal of Physical Chemistry A. 109 (3): 493–499
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