Kristofer S.J. Pister (Advisor)

Research Advised by Professor Kristofer S.J. Pister

Pister Group:  List of Projects | List of Researchers

Liquid to Vapor Phase Change in Constant Cross-Section Silicon Microchannels

Brenda Haendler
Albert P. Pisano
Dorian Liepmann
Kristofer S.J. Pister
2003
This paper presents research on the evaporation of methanol/water mixtures in uniformly heated, constant cross-section, serpentine silicon microchannels for potential application as a fuel injection system for a MEMS rotary engine. The phase change of a variety of mixtures of methanol and water was observed, characterized and compared to the phase change both of pure water and pure methanol. Seven different fluids were tested: pure water, pure methanol and five different molar fractions of methanol mixed with water....

Solid Propellant Microrockets

Dana Teasdale
Kristofer S.J. Pister
Albert P. Pisano
2000

This paper details the design, fabrication and testing of millimeter scale solid propellant rockets for use as one-time deployment platforms carrying communication-equipped MEMS sensor systems, known as Smart Dust. Each rocket assembly is an integrated system, incorporating a combustion chamber, composite propellant grain, nozzle, igniter, and thermoelectric power converter. Solid propellant is advantageous for a millimeter-scale single-use device because of its simple implementation, unlike liquid propellants, which...

Algorithms for Position and Data Recovery in Wireless Sensor Networks

Lance Doherty
Kristofer S.J. Pister
Kannan Ramchandran
2000

Networks of hundreds or thousands of sensor nodes equipped with sensing, computing and communicationability are conceivable with recent technological advancement. Methods are presented in this report to recover and visualize data from wireless sensor networks, as well as to estimate node positions. Acommunication system is assumed wherein information from sensor nodes can be transferred to acentralized computer for data processing, though suggestions are made for extensions to distributed computation. Specifically, this...

Optical MEMS for Free-Space Communication

Lixia Zhou
Kristofer S.J. Pister
Joseph M. Kahn
Roger T. Howe
Alice M. Agogino
2004
The convergence of MEMS technology with communication and digital circuitry makes high-speed, low power, free-space communication links over distances up to several km possible. MEMS corner cube retroreflectors (CCRs) are proposed to work as a passive optical transmitter, sending collected information back to an interrogating center. MEMS scanning microm...

Piezoelectric Aluminum Nitride Vibrating RF MEMS for Radio Front-End Technology

Gianluca Piazza
Albert P. Pisano
Roger T. Howe
Liwei Lin
Kristofer S.J. Pister
2005
The demand of consumer electronics for RF filters and frequency reference elements has focused attention on the reduction of size, power consumption and price and pushed current research interests towards the manufacturing of a single-chip, integrated RF solution. Vibrating contour-mode MEMS resonators constitute the most promising technology for ultimately realizing this vision. This dissertation presents analytical and experimental results on a new class...

Microfabricated Silicon High Aspect Ratio Flexures for In-Plane Motion

Christopher Guild Keller
Roger T. Howe
John W. Morris, Jr.
Kristofer S.J. Pister
Timothy D. Sands
1998

High aspect ratio microfabricated silicon flexures for in-plane motion were made by three methods: (1) 2-sided timed bulk etching in aqueous potassium hydroxide (KOH), (2) deep reactive ion etching (RB) with Cl2/He, and with SF6 (Bosch process), and (3) the hexsil ...

Micromachined Resonators

Dubravka Bilić
Roger T. Howe
Kristofer S. J. Pister
Roberto Horowitz
2001

In this work, we present approaches of making a micromachined resonators and oscillators. In the first study, we investigated the effects of anchoring on the resonator's performance. Using the Analog Devices BiMEMS integrated technology, double-ended tuning fork resonators have been fabricated with on-chip circuitry. The results show an improvement in the resonator's quality factor when using anchors with multiple contacts to the substrate. Resonators with frequencies up to 3MHz were tested at µTorr pressures to give quality factors as high as 58,000.

In order to reduce...

Miniature-Scale and Micro-Scale Rotary Internal Combustion Engines for Portable Power Systems

Kelvin Fu
A. Carlos Fernandez-Pello
Albert P. Pisano
Kristofer J. Pister
Dorian Liepmann
2001

This work describes the development of both miniature-scale and micro-scale rotary internal combustion engines. This work is part of a project to develop a portable, high specific energy, liquid hydrocarbon-fueled power supply. A Wankel-type rotary engine was chosen for development because of its self-valving operation, planar geometry, and the ability to extract either mechanical or electrical power. To investigate engine behavior and design issues, larger-scale "mini-rotary'' engines have been fabricated from 4 steel. Mini-rotary engine chambers are approximately 1000 mm3 to 1 700 mm3 in...

Algorithms for Distributed Sensor Networks

James D. McLurkin
Kristofer S. J. Pister
1999

A distributed sensor network is many (100-10000) autonomous sensor nodes spread out over a large area. Each node is equipped with a processor, mission-specific sensors, and short-range communications. Local interactions between sensor nodes allow them to reach global conclusions from their data. This work develops algorithms that allow:

The group to establish robust spatial patterns of messages The group to develop a communications network by dividing tasks among themselves Each mote to determine its position in physical space based on their location in the network topology Each mote...

A System Supporting Tiny Networked Sensors

Jason Hill
David Culler
Kristofer Pister
2000

As the post-PC era emerges, several new niches of computer system design are taking shape with characteristics that are quite different from traditional desktop and server regimes. One of the most interesting of these new design regimes is networked sensors. The networked sensor is enabled, in part, by "Moore's Law" pushing computing and storage into a smaller, cheaper, lower-power unit. However, three other trends are equally important: complete systems on a chip, integrated low-power communication, and integrated low-power devices that interact with the physical world. The combination of...