MEMS Gyroscope Research Based on UB Seed Grant

In this poster, the research on a novel MEMS gyroscope device based on UB faculty seed grant support is introduced. MEMS (Micro-electro-mechanical Systems) vibratory gyroscopes have attracted tremendous interest among researchers due to their small size, low energy consumption, low cost and long life-time. In my research, I conceived a novel bulk-micromachined electrostatic comb-driven, differential capacitance sensing MEMS vibratory gyroscope based on glass-silicon-glass sandwich-structure. The novel structure eliminates the parasitic capacitances of the gyroscope, which greatly eases the signal sensing. Furthermore, due to the device structure design, the sensing vibration is not coupled to the driving vibration, which improves the device stability. The MEMS gyroscope research is funded by UB seed grant. Based on the research, we published 1 journal paper and 1 conference paper. The research also resulted in the submission of 4 grant proposals, leading to a total funding of $60,016.77

Multi-objective optimization and life-cycle-cost analysis of a smart home

Linfeng Zhang's and Xingguo Xiong's poster on multi-objective optimization and life-cycle-cost analysis of a smart homes

Efficient SOPC-Based Multicore System Design Using NOC

Due to the advancement of VLSI (Very Large Scale Integrated Circuits) technologies, we can put more cores on a chip, resulting in the emergence of a multicore embedded system. This also brings great challenges to the traditional parallel processing as to how we can improve the performance of the system with increased number of cores. In this paper, we meet the new challenges using a novel approach. Specifically, we propose a SOPC (System on a Programmable Chip) design based on multicore embedded system. Under our proposed scheme, in addition to conventional processor cores, we introduce dynamically reconfigurable accelerator cores to boost the performance of the system. We have built the prototype of the system using FPGAs (Field-Programmable Gate Arrays). Simulation results demonstrate significant system efficiency of the proposed system in terms of computation and power consumption. Our approach is to develop a highly flexible and scalable network design that easily accommodates the various needs. This paper presents the design of our NOC (Network on Chip) which is a part of the platform that we are developing for a reconfigurable system. The major drawback of SOPC based systems lies in the routing of the various on-chip cores. Since it is technically difficult to integrate more than one core on a single chip, we come across several routing problems which lead to inefficient functioning. Thus we implemented several NOC based routing algorithms which considerably improve accessing speed and enhance the system efficiency

Glitches in Digital to Analog Converters

Digital-to-analog converters (DACs) are widely used for signal processing and other applications. A popular Digital-to-Analog Converter (DAC) topology is the R-2R ladder. It is a simple topology which consists of only two resistors and a switch per bit, and typically one OPAMP buffer at the output. However, such a topology is vulnerable to glitches (voltage spikes) that may occur when several bits in the digital input change at the same time. Although a DAC is often followed by a Reconstruction Filter (RCF), this filter may need to be of a high order to attenuate the voltage spikes sufficiently. Such a filter increases the size of the die in an integrated circuit (IC), or requires more spaces, components and increases cost for a printed circuit board implementation. In some applications, such as an analog control signal to a valve, the filter may not even be necessary, but it is probably desirable to not have glithces. In this work some alternative topologies that eliminate glitches are considered, primarily DACs based on R-2R ladders that accept Gray code input

Design and Simulation of a BioMEMS Leukocyte Counter with Concurrent Processing

Cell counting (such as white blood cells, red blood cells) is a popular technique being used in blood testing for disease diagnosis. It can give important indication about the health condition of a patient, and give hints for doctors to effectively diagnose disease. In this poster, a BioMEMS (Bio-Microelectromechanical Systems) cell counter with concurrent processing is proposed. It has presorting stage to separate out red blood cells, white blood cells and/or other cells of interest from the microfluidic flow of blood sample. The cells are then passed to branching stage to divide it into multiple braches. Each branch allows cells to pass through the microchannel in series. The cell counting is achieved by electrical impedance sensing. By introducing concurrent counting based on branching, it leads to faster throughput and improved efficiency. The proposed BioMEMS cell counter is designed and simulated in COMSOL. Simulation results verified the correct counting function of the cell counter device

Carbon Nanotube-based Ultra-sensitive Breath Acetone Sensor for Non-invasive Diabetes Diagnosis

In this project, the design and theoretical analysis of an ultra-high sensitive breath acetone sensor based on carbon nanotube (CNT) structure is proposed. In this device, a carbon nanotube is anchored to a substrate in one end, and the other end is coated by -WO3. As a ferroelectric material, -WO3 has high selectivity in acetone absorption. The end tip of carbon nanotube is coated with -WO3 material to absorb minute acetone molecules in breath sample. Piezoelectric activation is used to activate the vibration of carbon nanotube cantilever structure. When acetone molecules are absorbed by the coated -WO3, the resonant frequency of the cantilever will be changed for a certain amount. By sensing this certain resonant frequency change, the existence of a single acetone molecule can be detected. A theoretical model is developed to describe the vibration of the carbon nanotube cantilever structure. The resonant frequency change of the cantilever due to attached mass is analyzed. The proposed breath acetone sensor can achieve extremely high sensitivity in molecular level. It can be potentially used for non-invasive diabetic's diagnosis, which leads to a quick, convenient, accurate and painless breath diagnosis of diabetics

Automatic Bio-MEMS Smart Drug Delivery System

Traditional medicine injection is done by medical professionals. Patients need to see doctors or nurses for medicine injection. This brings inconvenience for the patients and increases the cost of medical care. Many senior patients with chronical diseases may need to inject multiple medicines everyday. Remembering the sequence of what medicine to inject at what time is not an easy job. Some medicine (such as insulin for diabetic patients) need to be delivered with precise dosage control according to the patient’s real-time need. Manual injection by rough estimation may lead to under-dose or overdose. All these made the medicine delivery a complicated and challenging task. In this research, a smart drug delivery system which can automatically inject the medicines according to preprogrammed sequence is proposed. It consists of a micropump, micro drug reservoirs and microneedle array integrated with a smart control circuitry. It can deliver multiple medicines with precise dosage control and proper timing. It allows the patients to injection medicine anytime anywhere automatically without human interference. It makes the medicine injection a worry-free process. The proposed smart drug delivery system leads to improved efficiency and it is expected to bring revolutionary change to the current medicine delivery technology

A Novel Reconfigurable Multi-Input Multi-Output (MIMO) Micropump for Micro Drug Delivery System

Micropumps are important bio-MEMS (bio-Microelectromechanical Systems) devices used to drive microfluid to flow along microchannels. They are widely used for Micro Total Analysis System (μTAS), Lab-on-a-chip, micro drug delivery systems and many other applications. A typical micropump has only one inlet and one outlet. In this poster, a reconfigurable multi-input multi-output (MIMO) micropump for micro drug delivery application is reported. The proposed micropump has six inlets and six outlets. The micro-valve in each inlet and outlet can be controlled individually. As a result, microfluid can be pumped in from any (or multiple) inlets(s), and pumped out to any (or multiple) outlet(s). Piozoelectric actuation is used in the micropump design. The proposed MIMO micropump can be used for multi-drug delivery system and other applications

MEMS Piezoelectric Vibration Energy Harvester with Three-DOF Responses

© ASEE 2015Vibration energy harvester can convert mechanical vibration energy into electrical energy and store it in battery for later use. It can create clean renewable energy from vibration movements such as walking, jumping, running, etc. This can convert energy previously wasted into useful energy for charging portable electronic devices, wireless sensors. If such devices are widely used, it can generate a large amount of green energy and help protect the environment. Most MEMS energy harvesters are designed to harvest energy from one direction only. In this research, a MEMS piezoelectric vibration energy harvester with three-DOF (degree-of-freedom) responses is proposed. The device consists of two silicon masses suspended by two sets of T-shape beams from both sides. The four sets of folded beams in both sides allow the mass to vibrate along the X direction. The two sets of straight beams allow the mass to vibrate along both Y and Z directions. The Piezoelectric material is pre-deposited along the surfaces of the beams. It can convert the vibration energy of beams into electric voltage, which is passed through a rectifying circuit to charge a battery. The device can harvest vibration energy along all three axes, resulting more effective energy harvesting outcome. It is designed and simulated in COMSOL. The proposed MEMS energy harvester can be attached to shoes, tires or other vibrating surfaces to harvest energy from the movement of walking, running, driving for clean energy generation.Electrical Engineering Department, School of Engineering, University of Bridgeport

Design of Self-cycling QCA Multiplier

Quantum cellular automaton technology (QCA) is a newly-developed technology for next-generation nanoelectronics. It results in high device density, ultra-fast speed and almost zero power dissipation. Multiplier is an important unit in microprocessor design. Traditional N-bit array multiplier consists of N*N adder units and results in large circuit area. In this poster, a novel area-efficient self-cycling architecture for N-bit multiplier is proposed. It ingeniously utilizes the inherent pipeline feature of QCA clock zones to convert the array multiplication into a serial-in serial-out process. In this way, the N-bit multiplier can be implemented with a single (instead of N*N) adder unit, which leads to significant area saving. The proposed self-cycling architecture can be extended to other N-bit QCA circuits as well. It is especially suitable for area-critical QCA circuit design where serial output can be accepted