When the University of Hawai‘i at Mānoa fielded its first team ever to compete in the annual National Institute of Standards and Technology’s Microrobotics Challenge—held in May 2011 in Shanghai, China—the Honolulu contingent made quite an impression among competitors from the mainland U.S., France, Italy and Canada.

Electrical engineering graduate students Wenqi Hu and Kelly Ishii finished second among seven teams in the challenge of building mobile robots smaller than 1 millimeter in size. Plus, they were members of the only team besides the winning one, University of Waterloo, that was able to assemble more than a single triangle in the micro-assembly challenge. “We were pleasantly surprised to do so well, because we didn’t have much time to work on this project,” said team advisor and Electrical Engineering Assistant Professor Aaron Ohta.

The stellar showing under Ohta’s tutelage was not surprising. The 1999 Kalani High graduate displayed youthful promise when, while enrolled at UH Mānoa in the early 2000s, Ohta was recognized by the national honor society Eta Kappa Nu as the top electrical engineering undergraduate in the U.S. The first UH engineering student to receive the prestigious National Science Foundation Graduate Research Fellowship, Ohta went on to earn his master’s from UCLA in 2004 and PhD from UC Berkeley in 2008, before returning to his alma mater to teach in 2009.

It was easy for Ohta to impart his enthusiasm for the world of microrobotics to Hu, Ishii and engineering student Michelle Zhang, who assisted in earlier stages of the project with Electrical Engineering Assistant Professor David Garmire. They were all fascinated by microrobots that are less than 0.6 millimeters in their largest dimension, which is no larger than the width of six strands of hair. UH Mānoa’s microrobot consisted of a very tiny air bubble inside a microchamber, whose surface was heated by a computer projector. The generated force propelled the microrobot, which in turn could move objects smaller than a millimeter in size.

At the Microrobotics Challenge in Shanghai, the tiny robots competed in miniature arenas under a microscope. The competition consisted of two events: a mobility challenge, in which the robots were timed as they moved around a figure-8 track; and a micro-assembly challenge, in which the robots assembled tiny triangles in a designated area. In a show of school spirit, the UH Mānoa team also assembled tiny glass beads into a “U” and a “H.” Go Warriors!