A quiet Saturday afternoon at the Engineering School turned into a day at the zoo, as alumni, students, and family filled the E-Quad entrance to enjoy "Gizmos and Gadgets," an Alumni Day activity. The influx of youth and families breathed life and activity into a normally calm E-Quad.

Assistant Professor of Computer Science Perry Cook's exhibit set the tone with "Making Music with Computers." His arrangement included, among other things, an accordion like instrument, fitted with electrical sensors, and a coffee cup with touch sensors on the outer surface. Activating the sensors would send information to a computer, which would then produce a corresponding sound.

"These are different ways of controlling music with either everyday objects or modified musical controllers," said Professor Cook, as children composed a background clamor with these new-age musical instruments.

Instant ice cream

Eyes turned to Professor Stephen Lyon of the electrical engineering department as he walked in with a tank of liquid nitrogen. For effect, Professor Lyon thrust his hand into the nitrogen at -196C.

"Your hand is so hot, and [the liquid nitrogen] boils off so fast that there is a skin of gas all around your hand," he said. Others stuck their hands in the liquid nitrogen to demonstrate this effect for themselves.

The liquid nitrogen was for making ice cream. Clouds of nitrogen spilled out of his food mixer, and inside sat a frosty mixture of two-parts heavy cream, two-parts light cream, one-part honey, and a heavy dose of liquid nitrogen.

"The reason it makes good ice cream is because by freezing it really, really fast, it forms little tiny crystals instead of like in the refrigerator," Professor Lyon said. "If it thaws and then freezes again, you get big crystals in it, and it's no good. It makes really tiny crystals, and that's what you want for ice cream."

After trying it, Jon Glass, 14-year-old brother of Jacob Glass '03, stuck to traditional standards, saying, "No, Ben and Jerry's is much better."

Others thought differently of the liquid nitrogen ice cream.

"That's good ice cream," Elizabeth Strickland attested. With food on his mind, her father, Department of Electrical Engineering alumnus Steve Strickland '74, said, "We're going to the Hoagie Haven after this. I remember taking trips to the Haven as an undergraduate and ordering souvlaki."

Other alumni returned, finding things had not changed.

It's a train thing

"Littman was here," said Mark Hopkins *83, who received a master's degree from the Department of Mechanical and Aerospace Engineering. "The guy running the trains

Professor Michael Littman of the Department of Mechanical and Aerospace Engineering was indeed operating two train sets and was also displaying a bridge made of Kinex�.

"They told us that alumni and their families were coming. I wanted to use the opportunity to show projects from my classes and advertise student work," Professor Littman said.

The train sets were a part of his class MAE 412: Microprocessors for Automation and Control. Students in the class each built a small computer and then programmed it to digitally control the actions of their train set.

Mark Holveck '01 and Tom Vessella '01, who had designed one of the sets, helped monitor the station.

"The trains are my favorite," said Alexander Ma, five-year-old son of Yuan Y. Ma *74 *82. He and young attendees watched the trains as they performed complicated tasks such as loading and unloading cargo and stopping at red lights.

The children were not the only ones with curious eyes. Many of the alumni found the technologies very interesting and jotted down notes on the more recent ones.

Optical Illusions

In particular, Professor Paul Prucnal's exhibit from the Center for Photonics and Optoelectronic Materials (POEM) attracted much attention.

"The graduate students set up a fiber-optic communication link, just to show how you can take a light beam from a laser and put a digital signal on it, send it through a fiber, and then receive it on the other end," said Professor Prucnal.

A robot team

The afternoon wound down with the children manning the controls of a robot that a team of students from Trenton Central High School had built under the guidance of Glenn Northey, a member of the E-Quad machine shop's technical staff. Undergraduates Leigh McCue '00, Thomas Sanderson '00, and Rebecca Taylor '01 also consulted on the project.

The robot team had performed well in a national competition against other teams sponsored by Daimler Chrysler and General Motors. The robot was on display at Alumni Day and demonstrated its flexibility and maneuverability by chasing people around the area.

Ed Shaya '76, astronomy, said of his daughter, "The older one has always been interested in this type of stuff, building and engineering."

By the end of the day, it was evident that the demonstrations inspired interest and showed a young generation that engineering really can be all fun and games.

Professor Michael Littman, left, demonstrates computerized trains to Ben Dahl. Tom Vessella '01 looks on.

Above, from left, Caterina Teuscher '03, Electrical Engineering Professor Steve Lyon, and Jon Thomas '04 make liquid nitrogen ice cream at the Gizmos and Gadgets event on Alumni Day.

Left, Trenton High School students Chrisinger Bennett, left, and Brenda Cortz, right, show Christian Ference the robot they built.

Photos by T. Kevin Birch