"Civil and Environmental Engineering at MIT"
is published quarterly by the
Civil and Environmental Engineering Department at Massachusetts Institute of Technology,
Bldg. 1-383, 77 Mass. Ave., Cambridge, MA 02139

Editor: Debbie Levey
(617)253-7101
levey@mit.edu

Sensors installed on Bldg. 1 flagpole

By Denise Brehm, in Tech Talk 4/3/02

            On a breezy day, a flag can take a real beating as it blows around at the top of a flagpole. Now there’s a way to know just what conditions are like on that pole., thanks to a project that placed sensors at the top of one campus flagpole to transmit data to a web site in real time.

            The 102-ft-tall flagpole in DuPont Court outside Bldg. 1 was outfitted with a specially designed system of sensors in February to monitor the motion of the flagpole in the wind. These sensors provide measurements of the response of the structure to the wind, which are combined with measurements of wind conditions and temperature taken by sensors in an environmental monitoring station on top of Bldg. 1.  Data from both sets of sensors are continuously transmitted to computers through wireless and wired connections, and placed on the project web site at http://flagpole.mit.edu.

            The iCampus Flagpole Instrumentation Project was conceived by Kevin Amaratunga, the Rockwell International Career Development Assistant Professor of CEE, and his colleagues as an educational experiment combining information technology with the more traditional civil engineering study of structures.

            “Students typically experiment in indoor laboratories. The main idea behind this project is to give them a real-world structure to experiment with, by turning the campus into a virtual laboratory,” said Amaratunga.

            We started out by proposing that we instrument the Stata Center construction, but there was lots of uncertainty involved with scheduling, so to make it more manageable, we decided to go with something smaller. The flagpole is a very visible structure to students in Bldg. 1.  It’s also fairly representative of the simple structures that they’d look at in a lab anyway.

            “The other idea behind the project was to expose students to new advances in information technology and sensors. It really combines IT (Information Technology) with the traditional side of civil engineering,” he said.

            Two grad students in CEE, Sudarshan Ragunathan and Matthew Echard, handled the majority of the software development and built the sensor boxes,with the help of MEng (Masters of Engineering) students, who also built the project web site.

            John Coyne, who climbs tall structures for a living, was hired to place a sensor box at the top of the pole, another about a quarter of the way down and a third at the halfway point. He spent about three hours at the top of the flagpole, which was visibly rocking in stiff winds, on Feb. 15. Photos on the project web site document his climb, as well as the extensive view from atop the flagpole.

            A data acquisition box buried at the foot of the flagpole collects data from the sensors and transmits it to a computer indoors. From there, the data is broadcast live on the web. The data will be used by students in two undergraduate courses and two graduate courses in CEE.

            The environmental monitoring station on Bldg. 1 was developed by Prof. Louis Bucciarelli in parallel with the flagpole sensing system. The project was funded by iCampus, the MIT-Microsoft Alliance, as part of the iLab initiative led by Prof. Jesus del Alamo of Electrical Engineering/Computer Science.

Editor's note:

            Various students, faculty, and staff clustered around the Bldg. 1 flagpole and shivered in the sharp February wind during the sensor installation, as they kept pointing out how far the top of the pole wobbled back and forth. Lean and weathered John Coyne of USA Signs remained quite unperturbed as he methodically checked the ropes and the safety belt around the flagpole to which he clipped his body harness.

            Over the years, Coyne has scaled most of the high spots of Boston, including the 125-ft (40 m) radio antennas on top of the 60-story John Hancock Building. He always carries a camera and takes 360º panoramic views from the summit. Although the view from the top of the flagpole is not as dramatic as from a skyscraper, his bird's eye pictures of campus and the changing Boston skyline are exhibited on http://flagpole.mit.edu/sinstallation4.html (and 3.html).