1. 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
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.
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 Design by Jeff Jackson (2003)
FUTURE WORK
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.
Design by previous VIP researchers (2015)
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.
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.
Block Diagram 1