IMPLEMENTATION OF THE ENIAC ACCUMLATOR AND CYCLING UNIT ON A FIELD PROGRAMMABLE GATE ARRAY (FPGA)

Advisor: Dr. Jan Van der Spiegel

ABSTRACT: An accumulator and cycling unit from the Electronic Numerical Integrator and Calculator (ENIAC) are implemented on a Field Programmable Gate Array (FPGA). The FPGA implementation is not architecturally identical to the original ENIAC, but the original architectural design is maintained where possible. The design maintains decimal number representation, ring counters to increment numbers, and ten different clocks to coordinate various accumulator functions. The implementation is a preliminary step in the design of a series of FPGAs that will include a constant transmitter, three accumulators, be connected to panels similar to those of the original ENIAC and be an exact replica in the programmer’s experience. View Paper | View Slides

SONY AIBO MOTION CALIBRATION AND MONITORING/CONTROL SYSTEM

Microsoft Fellowship Recipient
Advisor: Dr. Daniel Lee

ABSTRACT: The Sony Aibo are robotic dogs used to test new ideas in artificial intelligence, computer vision, and robotic motion through the application of having the dogs play soccer. An important part of building the system the dogs use is debugging. There are two key parts to this process: calibrating the dog’s motions, and monitoring the dog’s sensory outputs and control input. Both parts of the process help the developer to understand how the dog perceives the world and acts in it. Each of these questions was addressed with a different system. A magnetic positional sensor device was used (along with dog control and data processing programs) to obtain calibration information about the dog’s various walks and kicks. A client/server system was developed to allow multiple users to access different sensory outputs, the dog’s command input (only one user at a time), and the dog’s standard output in order to facilitate system development and debugging. View Paper | View Slides

DIELECTROPHORETIC ASSEMBLY, INTEGRATION, AND CHARACTERIZATION OF FUNCTIONAL NANOSTRUCTURES

Advisor: Dr. Stephane Evoy

ABSTRACT: Nano-electro-mechanical systems (NEMS) are pivotal to integrated systems research. The ability to integrate sensors and processors on a single wafer has the potential to create highly sensitive and complex systems that respond to changing environmental stimuli. This project focuses on the assembly, integration, and characterization of both nanowires and nanotubes used in NEMS devices. Using dielectrophoretic assembly, the project assembled and electrically characterized Rh and GaAs nanowires as well as multi-walled carbon nanotubes (MWNTs). It also found optimum parameters for assembly for each of these nanostructures for a specific circuit design. The optimum conditions always involved applying a sinusoidal field of 100 kHz at an amplitude of 10 to 35 V. The duration of assembly varied from 1 minute to 5 minutes. The capacitive properties of contact pads play a critical role in assembly yields, and resistivity of MWNTs is inversely related to temperature. The research also raised questions about the physical structure of these nanostructures and how it may be affected by changing temperature. It appears that a critical temperature is reached at which the resistivity of the nanotube increases drastically. Finally, the project produced clamped MWNTs for future mechanical testing. View Paper | View Slides

OPTIMIZED METHODS FOR EARLY CANCER DETECTION VIA OPTICAL IMAGING WITH A REDOX SCANNER

Advisor: Dr. Britton Chance

ABSTRACT: Modern medicine requires more accurate resolution and newer detection methods to properly diagnose cancerous tumors. The purpose of the redox scanner is to utilize near-UV, visible light, and NIRS to image at low temperatures the biophysical signs of cancer, with the ultimate purpose of early detection and diagnosis for human patients. The scanner will perform these functions in vitro through 3-D imaging of metabolic redox biochemicals, hemodynamic signals, and injected artificial beacons of a tissue sample at 80 x 80 x 80 mm spatial resolution.

An outdated version of the redox scanner was operational but not ideal; in the scope of SUNFEST, the goal was to fabricate a prototype of an improved device based on the biomedical principles of the old machine, and then validate it in its initial stages by comparison of the actual test samples to the scanner data as modeled in Matlab.

During the 10-week span of SUNFEST, the project progressed from early development and low functionality to near completion. Several vital system improvements were implemented, to include a new optoelectronics driver circuit to provide reliability, a DOS motor controller to fix critical Windows timing errors, and Matlab imaging software. Trial results were promising and signal the possible end of the system design phase. The next phase will involve testing on an animal model to find the efficacy of the sensors on actual biological systems. View Paper | View Slides

ARCHEOVIZ: IMPROVING THE CAMERA CALIBRATION PROCESS

Advisor: Dr. Kostas Daniilidis

ABSTRACT: The reconstruction of archaeological scenes as three-dimensional graphical models can provide a very powerful tool for the archaeologists studying them. The purpose of the Archeoviz project is to develop a program that archaeologists can use in the field to create these three-dimensional models themselves, accurately and easily, using two-dimensional photos of the scenes. This paper describes my development of a program to make the process of camera calibration, necessary before any model building, as fast and easy as possible for the user. This calibration process requires locating and recording image coordinates of numerous small markers in the scenes. Originally, this locating had been quite time-consuming and had to be done separately from any calibration calculations. I have developed an independent C++ program that requires users to locate only six of these markers themselves. The program will then automatically locate the remaining markers for the user and calculate the calibration data. This program includes a user-friendly zooming interface and a file browsing system for retrieving and loading the images and for saving the calibration data obtained. In addition, an extension for the program will allow users to estimate the location of the markers in the second image of the stereoscopic pair from the calibration data for the first. Also, in order to obtain more accurate three-dimensional models, the reconstruction will incorporate stereo pairs from multiple views of a scene. Through another extension, the calibration data from the first of these pairs can be used to predict the location of all markers in all subsequent stereo pairs. Through these various improvements, my program greatly speeds up this calibration process and allows archaeologists to quickly move on to constructing these valuable models. View Paper | View Slides

THE CONSTRUCTION OF A MICRO-COULTER COUNTER DEVICE

Advisor: Dr. Haim Bau

ABSTRACT: This report explains the general applications of the Coulter counter, discusses its benefits, and reviews literature in which researchers have used the device as a research tool and in biosensor applications. Coulter counters are electrofluidic devices commonly used to measure the size and the number of particles in a sample. The paper also reports the design and fabrication of a Coulter counter device constructed using Polydimethylsiloxane (PDMSX) and also one of a carbon nanotube based Coulter counter. These devices were desired to sense particle size through a change in resistance displayed through a current spike. Microfabrication was required to construct the device and prepare it for electrical and optical sensing. Potential concerns such as fabrication optimizing and mishaps, troubles with trapping, and as pore filling issues were evaluated and tested. Not all issues were resolved, and a functional Coulter counter device was not completed. However, with detailed microfabrication steps, revised trapping procedures, and improved troubleshooting, the groundwork for a functional device was laid out for implementation in the near future. View Paper | View Slides

BINAURAL SOUND LOCALIZATION

Advisor: Dr. Dan Lee

ABSTRACT: Acoustic localization is an important process used by humans and many animals. Bringing this sense to an artificial system has many possible applications. The system explored here is the commercially available Sony Aibo ERS-210 robot dog. The primary goal is to use this robot dog to track white noise sources in the forward hemisphere. Physically modifying the original equipment allowed for better tracking of such sounds in the vertical direction; prior to this modification, there was very little variation in the spectrum of the recorded sound as a function of elevation. Templates of spectra at different elevations combined with the time delay between ears allowed for varied accuracies. The lowest standard deviation of errors occurred at a position directly in front of the robot dog, while the greatest errors were at the periphery of its sight. The range of standard deviation of errors for phi and delta in the forward hemisphere are as follows: lowest standard deviation of error in Delta occurred at 15 degrees azimuth and 0.3 radians elevation or (15, 0.3): 0.1042; highest standard deviation of error in Delta at (-90, 0): 25.804; there was never any error in Phi at these locations: (-45, -0.6), (45, -0.3), (5 & 15 & 45, 0), (-45 & -15 & 15 & 45, 0.3), (0 & 15, 0.6). View Paper | View Slides

BUILDING A PROTOTYPE OF A 3-D DISTRIBUTED MOBILE SENSOR NETWORK

Advisor: Dr. Daniel D. Lee

ABSTRACT: Biological organisms have the ability to gather information over a variety of senses from multiple viewpoints for accurate sensory perception. Artificial systems typically use a static array of sensors that lack mobility, or employ motion in a robotic platform in two dimensions.

The goal of this project is to design and build a prototype of an adaptive, distributed sensor network utilizing small, modular sensors and actuating components that will accurately position sensors in three-dimensional space. A working prototype was built, using a simple motorized spool design and a Motorola HC11 microcontroller. The system monitors the current position in three dimensions using encoders. Based on the change of lengths of the network cables, the motors are set to spin at speeds that will achieve motion in the desired direction. Control of the system was implemented in C to position an adaptive network in three dimensions. A user interface using serial communication and infrared remote control was designed. View Paper | View Slides

MAGNETORESISTANCE OF ELECTROSPUN CARBON NANOFIBERS PYROLYZED AT LOW TEMPERATURES

Advisors: Dr. Jorges Avilles-Santiago and Yu Wang

ABSTRACT: Carbon fibers with diameters of approximately 100 nm can be produced by heating electrospun polyacrylonitrile (PAN) nanofibers in a reduced-pressure chamber. These nanofibers’ outstanding properties, especially their high specific surface area, make them promising materials for scaffolds in tissue engineering and also for high-performance filtration and sensor applications. However before any of these potential uses can be explored, the nature of these nanofibers must first be better understood.

One important quantum effect phenomenon that occurs in carbon nanofibers is magnetoresistance (MR).This is a measure of how the electrical resistance of the carbon nanofiber changes in the presence of a transverse magnetic field. To make this measurement, the PAN nanofibers were placed in the right orientation on a patterned silicon wafer by electrospinning. The PAN nanofiber samples were then pyrolyzed in a vacuum chamber at a temperature of 1173K to produce carbon nanofiber samples. The four-point probe method was used to measure their conductivity. Initially, the temperature dependence of the nanofiber was observed, with no applied magnetic field, within a temperature range of 0K to 300K. The resistance decreased exponentially as the temperature was increased. Then measurements were taken at temperatures of 1.9K, 3K, 5K, and 10K within a magnetic field range of -9T to 9T each. These current and voltage measurements were then manipulated to calculate MR. In general, MR was negative, and its magnitude increased with an increase in magnetic field and a decrease in temperature. This result was attributed to the weak localization effect model. View Paper | View Slides

REMOTE COGNOSENSORS: DEVELOPING AN NIR IMAGING MODEL TO MAP BRAIN FUNCTION

Advisor: Dr. Britton Chance

ABSTRACT: Near-infrared (NIR) imaging has provided new insight into optical imaging of human tissue. The purpose of this study is to develop an NIR imaging system that could potentially be used to study cognitive function by measuring the optical parameters (µa and µs`) of the human prefrontal cortex. The desired system should be a remote sensing system that does not need direct contact with the subject. It should also be able to work over a distance of 50 cm to 2 m from the subject. This study presents a method of remote sensing via a time resolved spectroscopy approach. Two methods of analysis are used: a single photon counting (SPC) method; and the second being a series of gated integrating circuits (Box Car). System design and initial results are shown for both systems. Actual photon migration patterns, from which values of µa are calculated, were obtained via the SPC method over a distance of 60 cm. Also, experimental results demonstrating pulse shaping are shown from the Box Car system. Finally, noise level reduction in the SPC method is taken into consideration, along with an option for achieving correct Box Car gate timing. View Paper | View Slides

CARBON NANOTUBE-BASED BIODETECTION OF TRIIODOTHYRANINE

Advisor: Charlie Johnson

ABSTRACT: We report biodetection of the thyroid hormone triiodothyranine (T3) using carbon nanotube field-effect transistors. T3 molecules bind non-covalently the semiconducting nanotube and donate electrons to the nanotube lattice, thereby altering its electronic characteristics via chemical doping. The effect is semi-reversible by rinsing the transistors with the T3 solvent without the biomolecule. The nanotube transistors are found to have no electrical response to the solvent itself. The results demonstrate that T3 can have an electrostatic effect on a one-dimensional system and may suggest an electrical interaction between T3 and DNA. View Paper | View Slides