Kristofer Pister


Applications of Wireless Sensor Networks

As the size, cost, power, and communication latency of wireless sensor nodes continues to decrease, wireless sensor networks have the potential to be used in a variety of new and interesting ways. In this project we aim to demonstrate applications and use cases that are possible with small, low power, and low latency networks; for example, collecting high- resolution personal telemetry via products with embedded sensor networks, networked autonomous robotic systems, smart buildings, and industrial process control.

Autonomous Flying Microrobots

Among the state of the art academic research on pico air vehicles, the majority has focused on biomimetic flight mechanisms (e.g. flapping wings). This project looks to develop a new microfabricated transduction mechanism for flying microrobots with the goal of opening up the application space beyond that allowed by the industry-standard quadcoptor. The proposed mechanism, electrohydrodynamic (EHD) force generated via sub-millimeter corona discharge, functions silently and with no moving parts, directly converting ion current to induced air flow.

Design of a MEMS Swimming Robot

This project is dedicated towards the design of a MEMS swimming robot capable of locomotion in liquid media. Some project goals include 1) characterizing individual mechanisms in aqueous environments, 2) integrating mechanisms to achieve swimming motion, and 3) identifying possible power sources.

Fabrication and Microassembly of a High-Density Carbon Fiber Neural Recording Array

We present a 32-channel carbon fiber monofilament-based intracortical neural recording array fabricated through a combination of bulk silicon microfabrication processing and microassembly. This device represents the first truly two-dimensional carbon fiber neural recording array. The five-micron diameter fibers are spaced at a pitch of 38 microns, four times denser than the state of the art one-dimensional arrays.

Jumping Silicon Microrobots

This project aims to create millimeter-scale MEMS-based jumping robots. These microrobots can be used in applications ranging from mobile sensor networks to planetary exploration. By using a simple two-mask Silicon-On-Insulator (SOI) fabrication process, planar mechanisms are easily integrated with electrostatic actuators. These electrostatic motors do mechanical work on a shuttle to store mechanical energy via the bending and stretching of silicon springs. Once a sufficient amount of energy has been stored, the motors release the stored energy and the microrobot can jump.

Miniature Autonomous Rockets

Pico air vehicles (PAVs), sub-5cm aerial vehicles, are becoming more feasible due to advances in wireless mesh networks, millimeter-scale propulsion, battery technology, and MEMS control surfaces. Our goal is to develop an aerodynamic MEMS control surface that could be used in PAV applications. This device uses electrostatic inchworm motors to rotate a thin silicon fin 10 degrees. We measured 1.6 uNm of output torque generated by the actuator.

MEMS Filament Motors

Pushup, walking, jumping, and flying microrobots have been demonstrated. Other previous work has demonstrated microelectromechanical systems (MEMS) capable of creating silicon silk, as well as microrobots capable of assembling millimeter scale carbon fibers. However, microrobots capable of manipulating very small diameter filaments, fibers, and wires initially external to themselves is still an area of open research.

Single Chip Mote

The Internet of Things (IoT) is a natural evolution of computing. CMOS technology enabled the network of computers that provided a platform for creating social networks. We are just seeing the early stages of another transition point in technology and entering into a new era where computing, sensing, and communication is essentially becoming disposable. The microsystem serves as a platform that allows us to embed wireless connectivity into everyday objects or serves as a brain for walking and flying microrobots.

Walking Silicon Microrobots

This project focuses on developing a new generation of sub-centimeter MEMS based walking robots. These robots are based on electrostatic actuators driving planar silicon linkages, all fabricated in the device layer of a silicon-on- insulator (SOI) wafer. By using electrostatic actuation, these legs have the advantage of being low power compared to other microrobot leg designs. This is key to granting the robot autonomy through low-power energy harvesting.

Zero Insertion Force MEMS Socket for Microrobotics Assembly

To help resolve the control and power challenges present in developing micro robots, the research focus of this project is the design and development of a ZIF (zero insertion force) MEMS socket. The ultimate goal is to achieve electrical connection between a 65nm single-chip mote and a multi-legged SOI micro robot. As proof of concept, the most recent socket prototype has demonstrated successful connection to a MEMS motor chiplet, which is orthogonal to the socket. Both chiplets were fabricated using a two-mask SOI (silicon- on- insulator) process.