Tuesday September 27, 2005 news@nichigandaily.com SCIENCE 5 v BUBBLES & BALLOONS IN THE BIG HOUSE More than a hundred University students and faculty conduct wind experiments in Michigan Stadium STADIUM Continued from page 1 Forecasting the Stadium To map out the wind currents of the stadium, the classes equipped themselves with the latest in weather technology along with balloons and bubble soap that could mark the movement of the wind for the students to see. Dave Pawlowski, a Rackham student and event organizer, said faculty members decided to separate students into four experiments. Each group would mea- sure specific features of the wind currents - like wind direction and temperature - with the students' par- ticipation. AOSS research scientist Frank Marsik, a faculty member who participated in the experiments, said because of the bowl-like shape of the arena some pro- fessors initially speculated wind passing over would spiral inside the stadium. Engineering senior Elizabeth Siegel, a student in Samson's AOSS 463 class also known as Air Pollution Meteorology, said students also predicated that incom- ing wind would cascade down the stands to the floor of the arena where the temperature is warmer and there- fore at a lower pressure. The wind would then naturally rise with the warming of the air on the 1football floor. But several "It'v rdays before the experiment, turbulent in here. Samson along with some of his The wind isn't all that strong, but the mixing is greater than we thought." -Perry Samson Atmospheric Oceanic Space Sciences Professor Engineering senior Alex Braden students and fac- ulty scoped out the arena. There they found piec- es of trash float- ing across the stadium floor. Coincidently, the pieces of trash acted as visual markers that showed the direction of the wind. "The trash was just crash- ing together," said, adding that the GRAPHIC BY LINDSEY UNGAR wind was acting in an erratic pattern no one could real- ly discern. "You could watch it blow together. There was a lot of turbulence," Samson said. It was only a taste of the wind currents' unpre- dictability that Samson and the students would see on Saturday. The night before the experiment, Samson couldn't sleep. Experimental difficulties By noon on Saturday, students from six classes filed through the vacant stadium, clad in yellow t-shirts with the words Extreme Weather written on them. At the center of the football field, AOSS faculty members set up a meteorological tower and weather balloon to record the vertical and horizontal wind con- ditions. Scattered across the stadium seats floated blue bal- loons tied to the ground, each acting as a marker to indicate wind direction. Meanwhile Samson directed the students to his attention on the south end of the football field in what would mark the start of the exper- iment - bubble blowing. Holding bubble bottles, dozens of students blew bub- bles through the air to indicate the overall wind direc- tion. But the hundreds of bubbles hovered up in the air in a chaotic motion. About 15 minutes later, students lined in a "human dispersion" experiment where they released a neutrally buoyant balloon - a balloon filled with enough helium to prevent it from rising or dipping in the air - on the stadium floor. One by one, students followed their balloon for about ten seconds before retrieving it and leaving a marker on where the balloon was recovered. In the end, the markers would indicate the dispersion of incoming wind plumes. Yet by the end of the experiment, the spatter of markers didn't leave a distinct trail. DAVID TUMAN/Daily LSA Freshman Hilary Bronson chases her ballon in the Big House on Saturday. GRAPHIC BY GERVIS MENZIES In the last moments, students holding balloons on twenty-foot-long strings stood across the foot- ball field in assigned positions to mark the different wind paths. But again, no evident pattern formed. While the students thoroughly conducted the experiments, Samson said none led to any substan- tial results. "The streamers (on the goal post) performed better than the balloons did," Samson said. "The human dispersion experiment. Nothing expected happened with it." Although the faculty and students will need time to decipher the results, which were recorded on vid- eotape, Samson said, "It's very turbulent in here. The wind isn't all that strong, but the mixing is greater than we thought." Back to the drawing board Samson said the stadium is very symmetrical but there are clearly nuances within the stadium, which are causing the erratic flow of wind. Research scientist Marsik said one of the factors that may have caused the erratic wind patterns could be due to the different colors throughout the sections of the sta- dium. Because the dark colors absorb sunlight, Marsik said the different coloring of the sections might create various temperature levels throughout the stadium. The resulting temperature levels would create disparate pressure levels, which could exacerbate turbulence in the stadium. Marsik added that another possible factor that could also increase the turbulence in the stadium would be the heat on the surface of the football field. If the temperature of the football field is warmer than the air above it, Marsik said the warm air will gradually rise. This will cause cold air from incoming wind currents to flow into the areas the warm air is leaving, ultimately causing greater wind flow. Despite the difficulties of the experiment, Samson said he and his students hope to obtain concrete results from the information of their weather balloon and meteorologi- cal tower. "Hopefully we can make some generalizations," Sam- son said. But even though Samson might not come with results this time, he plans on coming back next year with better experiments and more equipment. Samson said it's not really the results that really matter. "It's the act of trying to experiment that went well." 'Robots and their makers vie for $2 million grand prize at race Unmanned vehicles will travel across 150-mile course in government sponsored race LOS ANGELES (AP) -- Wanted by the Pentagon: A muscular, outdoorsy specimen. Must be intelligent and, above all, self-driven. - fitted with the latest sensors, cameras and computers - have aged a generation since last year. Teams have beefed up their vehicles' artificial intelli- gence through improved computer algorithms that will help them avoid pitfalls such as ditches and boulders strewn across the roughly 150-mile-long course. To get there, the robots must compete in a semifinal show- down that starts tomorrow. Entrants include several converted SUVs, souped- ver mountain switchbacks, squeeze through choke points and avoid man-made and natural obstacles. The sponsor of the Grand Challenge is the research arm of the Pentagon known as the Defense Advanced Research Projects Agency, or DARPA, whose best- known success story is the Internet. The Pentagon wants one-third of the military's ground vehicles to be unmanned by 2015. DARPA Director Anthony Tether hopes that a robot