Katy Purdum
University: Western New England College (WNEC)
Gradation Date: May 2009
Hometown:
My Project: Microscopic Robots: Characterization of How They Move
Microscopic robots are less than 100 micrometers long in their largest dimensions and are micro fabricated using semiconductor processing techniques. Advanced metrology tools, such as fluorescent microscopy and strobed interferometric microscopy, were used to measure a single step of the robots along with their three-dimensional motion during forward or turning motion. Possible applications of microscopic robots include the manipulation of nanoparticles and as surgical tools to remove clots and fat buildups from arteries and other blood vessels.
These robots consist of a body area and a raised arm with a disc on top, as shown in Figure 1. The arm is raised due to a coating of chrome layered on top of the robots itself. The arm and disc allow the robot to turn, which allows a greater range of motion for these robots. The body consists of a scratch drive actuator and is what allows the robot to actually crawl forward. It is used for the actual turning movement while the arm is snapped down to the dielectric that makes up the field which these robots move on.
These robots receive electrical power through a capacitive coupling. The resulting charge build-up causes part of the scratch drive to flex and come in contact with the dielectric, as shown in Figure 2. When the scratch drive fully relaxes again, such that the entire body is at a linear slope rather than the one seen in Figure 2, the robot begins to crawl forward.
Movement of these robots is dependent on the signal parameters (such as frequencies and amplitudes), along with the dielectric the field is made of and the roughness of the surface of that field.
Interferometric image of the robot showing the three dimensional look of a robot with no charge build-up. The disc seen at the end of the arm varies in height above the body and has been measured anywhere from 5µm high to 18µm high.
Interferometric three-dimensional image of the robot when flexed before movement (top) and two-dimensional graph showing the area that is flat along the scratch drive (bottom). The amount that comes in contact with the dielectric is dependent on the voltage applied.
My plans for the future are not nearly figured out yet- right now I hope to one day teach as a professor, but I would love to do research for a while before then. I do plan on enrolling in a PhD program somewhere after I graduate this upcoming May. SURF was a great experience and I’m sad I could only take part in it for just one summer.