VIP_TNI_Poster_Fall2016x - Purdue College of Engineering

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Transcript VIP_TNI_Poster_Fall2016x - Purdue College of Engineering

Technologies for Neuroimaging
Department of Electrical and Computer Engineering
Undergrad Team: Aaron Anderson, Megan Hedges, Hyunbae Chang, Guanghua Zha, Sahiyya Harrison, Yuqin Duan, Aaron P Rosenfeld, Logan R Miller, Aditya
Srikakulam Vikram
Professor: Thomas Talavage
GENERAL GOAL
Functional Magnetic Resonance Imaging (fMRI) is a
localized brain activity measurement technique. It
typically requires the subject to remain still while
interacting with an external stimulus. Video games are
effective stimuli of higher cognitive function. However, a
typical video game controller contains metal and thus
cannot be used due to detrimental interaction with the
strong magnetic field present during testing. A
completely nonmetallic controller is desired to
effectively provide brain stimulation for complex
sensorimotor investigation. A plastic and fiber optic
controller is being developed to meet these
requirements.
ORIGINAL CONTROLLER DESIGN
CURRENT WORK
Due to the limitations which existed with the previous
model, we are constructing an new prototype using
improved components and 3d printing techniques. We
have designed and are fabricating and testing a PCB to
convert optical signals to voltages. Current topics of
investigation are improving joystick mechanical design
and implementing USB HID protocol.
Original Design by Jeff Jackson (2003)
FUTURE WORK
Design by previous VIP researchers (2015)
The PCB will be tested for input/output response. An
opto-mechanical interface must be integrated into the
joystick design to relate light attenuation to axis
position. This, in turn, will be integrated with the
microcontroller on the PCB. Later, the controller will be
programmed to interface with current video games for
a more mentally stimulating fMRI experience.
Basic Implementation
PCB
PROTOTYPE DESIGNS
The user from a fMRI machine will hold the joystick with
one hand and move it. The signals are moved through
fiber-optic cables to a board where it is converted to
voltages. These voltage values are read into an Arduino
as analog inputs which are converted to digital outputs.
The Arduino is connected to a computer where it is read
as a game controller and thus allows the user to interact
with the computer.
The Printed Circuit Board for this project contains the
AT Mega 32U4 controller which will provide an
interface between the joystick and the computer via
1mm fiber optic cable, which will be intercepted by the
Analog and Digital optic receivers and transmitters.
In addition to the board, a case has been 3D Printed to
house the PCB and its fiber optic cables.
Block Diagram
The new controller is designed for durability and a
way to provide the opto-mechanical interface
needed to produce a varying light signal. The current
version of the joystick is able to vary the amount of
transmitted light based on joystick position. The
current version of the buttons discretely occlude
light when pressed. Now, the joystick and buttons
need to be integrated into one controller.