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Aseeseti2.doc rev 14 Aug 01 Multi-student, Multi-semester Design Project: Lessons learned from setting up a SETI station By Mr. Melvin Lewis, Lecturer Fairleigh Dickinson University School of Engineering and Engineering Technology
Abstract -This paper describes the objectives and approach used in setting up multi-year, multi-discipline SETI (Search for ExtraTerrestrial Intelligence) project. FDU-SETI has at its center, a five meter diameter parabolic dish, with the students designing, building and testing nearly everything else needed. Discussed are the pedagogical lessons learned from this first semester’s effort. The graded project is, in effect, a practical application of four years of theory and labs in the student’s field of study. There were diverse assignments for 15 senior electrical engineering, as well as mechanical, electrical, construction, and civil engineering technology students in the Spring of 2001 at FDU’s Teaneck NJ campus. FDU-SETI was an excellent environment for learning about teamwork and advance planning, technical writing and product testing -- all to complement the student’s design / parts procurement / fabrication and technical presentation skills. For example, they discovered that a comprehensive specification will help avoid needless design iteration, and a test plan will point out what instrumentation and other equipment is needed and when.These are all real issues encountered in industry, and what better place to first encounter them but in the learning environment of a senior project.
Background - the search for extraterrestrial intelligence had originally been funded by the US Govt. (NASA), but funding was discontinued in 1993. Private enterprises continue the search, notably the SETI LEAGUE (ARGUS), and the SETI INSTITUTE. Of course, public interest was sparked by movie Contact (starring Jody Foster).
What’s the difference in these two entities? The SETI League is an international grass-roots organization dedicated to privatizing the electromagnetic Search for Extra-Terrestrial Intelligence. Together, over a thousand members in five dozen countries are keeping alive the quest for our cosmic companions. This is a participatory science group. On the other hand, the SETI Institute (Mountain View, CA) is the world leader in the scientific hunt for extraterrestrial intelligence. Its Project Phoenix , which uses the impressive Arecibo Radio Telescope, is the most comprehensive radio SETI experiment ever undertaken. The Institute is also actively pursuing the use of optical techniques and the construction of the Allen Telescope Array, a new type of instrument that will be used around the clock for both SETI and astronomical study.
Motivation - very few industry design assignments allow the engineer to work in isolation. At FDU, prior university labs emphasized individual, isolated design. Again, much of the work in corporate environment is done on a project basis, with cross-discipline members and teams. There are internal and external customers, management and technical leads involved and at cross purposes, and multi-level teamwork is crucial. In academia, the importance of communication, technical and logistic, up and sideways, needs to be stressed in a graphic way, and the use of modem communication technology (web site / email) needs to be maximized.
Approach – The idea we came up with is to provide an interesting project involving multiple students (to promote teamwork), that embraces multiple technical topics and specialties (electronic, mechanical, structural, etc.). It should be difficult, challenging, but not impossible. It would be helpful if it increased the profile of the engineering dept. on campus. It was decided that it was not necessary to actually hear ET signals, at least not early on. The students need to learn how to deal with problems as they come up (man-made interference, false alarms, weatherproof power supplies, detection protocol, etc.). Not everything went smoothly in this first semester’s efforts, as described below. We developed an association with one of the existing organizations (SETI League, which emphasizes participatory science). Then the students with the principal investigator (this author) decided what frequency, antenna type to use. Then we had to obtain an antenna and any other equipment mostly via donation. The students were asked to design and build the rest with faculty help. Some circuit fabrication was accomplished through use of kits, modified for the SETI application (recognizing that the performance of the kit might be somewhat below what was needed). The students were tasked with writing the statements of need, technical specifications, test plans/procedures, etc. Then the students tested their building blocks stand-alone and where possible, with other SETI equipment.
Assignments – There was (and will continue to be) plenty to do for the 15 involved students (and follow-on students). Here’s a list:
Fig 1. Parabolic dish antenna (used surplus, donated by Dr. Alan Katz, SETI League) with feed horn and low noise preamplifier positioned at the focus. Lessons Learned – Administratively, the students found that they had to develop and maintain good working relationships: instructor/students, between students, instructor/school administration, etc. The faculty had to find funding, and a place to work, set up a budget, get it approved, carve out a corner of a lab so to speak. To improve communications, a web site was setup, an emailing list (group) was created for all involved. There were frequent meetings, where attendance was mandatory. We heard a brief report from each student, and required inter-student communication. We discovered that there is a need to assess progress more frequently than mid- and end of semester, as some students had fallen behind and it was difficult to tell.
Fig 2. Dish and supporting structure
With regard to work habits, one must keep student focus positive. Some students became discouraged (the project was too complex, too difficult, too fast paced). Information was not forthcoming from other students, attendance at weekly meetings became a problem), there were mysterious (paradoxical) technical problems that needed solving, students put tasks in series (few of them did "work-arounds"), some did not attempt to get their design to work first, but rather asked detailed questions before letting their design "do the talking". There was an issue with instructor availability (heavy workload, essentially one professor, with 4 other courses, assisting 15 project students). And there was excessive waiting (for information, parts, permission, etc.) when there were things that could be worked on.
Conclusions - Students should be given written project overview, including guidelines based on these lessons learned. The problems encountered were just like in industry, so this was good practice for working world, and a good topic for job interview discussion. Students have never encountered such problems in earlier labs. They encountered problems ranged from administrative to technical to work habits. The web site and email were essential, enforcement of mandatory meeting / lab session attendance needs to be addressed. And there should be frequent progress assessment.
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ASEE 
On the technical side, it was
confirmed that they should write out all requirements (in the form of specifications), to
avoid interfacing problems later on. We had weekly tutorials and briefings by the
instructor, especially early-on, and these proved to be valuable. There were parts
shortages (just like in industry), especially exotic parts that can’t be found in
Radio Shack. A big problem was the dependence of one student on another, whether it be a
hardware circuit, a critical piece of software, the absence of which produced testing
problems. It proved useful to the students to be working across disciplines
(electrical/mechanical, for example). We discovered a generalized hands-on unfamiliarity
with tools and materials. Some students didn’t know where to get parts (outside of
Radio Shack). They made design changes without communicating that information to affected
students. There was some student reluctance to simulate their circuits on the computer,
and an over-reliance on internet for information. 