Conferencia "Magnetically-and-Bacteria-Actuated Mobile Micro-Robots"

ORIGINAL: Wyss Institute - Harvard

Thursday, Aug 9, 20122:00pm – 3:00pm

Wyss Institute, Room 521, 3 

Blackfan Circle, Boston, MA 02115

Speaker:

Metin Sitti, Ph.D.

NanoRobotics Lab & Center for Bio-Robotics, Carnegie Mellon University

Host:

Robert J. Wood, Ph.D.

Core Member, Wyss Institute for Biologically Inspired Engineering at Harvard University

Member, Kavili Institute for Bionano Science and Technology

Gordon McKay Professor of Electrical Engineering

Minature mobile robots have the unique capability of accessing to small spaces and scales directly. Due to their small size and small-scale physics and dynamics, they could be agile and portable, and could be inexpensive and in large numbers if they are mass-produced. Miniature robots would have potential future applications in

• health-care,
• mobile sensor networks,
• desktop micro-manufacturing,
• enviornmental monitoring, and 
• inspection.

In this presentation, miniature mobile robots with tens or hundreds of micrometer overall sizes and various locomotion capabilities are presented. Going down to tens or hundreds of micron scale robots, significant challenges are on-board actuation and power sources. Two alternative approaches are proposed in this talk to solve this challenge. 


First, external magnetic actuation is used to move permanent magnet micro-robots using a stick-slip or rolling based surface locomotion in air or liquid in 2-D and using a rotating rigid or flexible flagella based swimming locomotion in liquid in 3-D. Vision-based control schemes can individually control singe- or teams of micro-robots and these robots can manipulate and assemble micro-objects with or without contact in liquid. Various local addressing and motion control methods for teams of magnetic micro-robots using global magnetic fields are proposed. Controlled assembly and disassembly of such teams of magnetic micro-robots are also investigated and demonstrated towards reconfigurable micro-systems in 2-D. 
As the next approach, a cell-based actuation principle is used to propel micron scale robotic bodies in liquid by harvesting the flageller propulsion of the attached bacteria. Stochastic swimming of these S. marcescens bacteria attached micro-objects can be stopped and resumed repeatedly using chemical switching. Their motion can be steered using attractive or repulsive chemical gradients in the liquid medium. Preliminary stochastic dynamics and steering of such bacteria propelled micro-objects are demonstrated by simulations and experiments. 

Contact information: caitlin.wells@wyss.harvard.edu