MILLER, Alan R.
Department of General Engineering, New Mexico Tech, 801 Leroy Pl., Socorro NM 87801-4796, Phone: 505-835-5619, Fax: 505-835-5209, armiller@nmt.edu, http://www.nmt.edu/~armiller/
Abstract: Our efforts to improve engineering education and increase retention at New Mexico Tech over the past several years address several of the 17 discussion topics of this conference. Two of the conference topics, innovating curricula content and applications of new communication and information technologies, are covered by our integration of computer programming into many engineering classes. We generally use Matlab as the programming language. Ansys is used with our finite-element course, where much of the course material is available on the web at http://www.nmt.edu/~es421/.
By combining students from more than one discipline, our junior and senior engineering design classes expose students to multidisciplinary design. For example, mechanical, electrical, and materials engineering students jointly design robots and our solar racecar.
Convenient and rapid communication for students and faculty is possible because our campus offices, laboratories, and dormitories are provided with Ethernet connections. Furthermore, the buildings are linked by T1 optical fiber. Three New Mexico State universities and two U.S. Government laboratories located along the Rio Grande Corridor are connected by optical fiber. This allows regular college courses to be exchanged by television. Some laboratories are fitted with digital sensors that can be fed into the Internet so that the readouts can be observed remotely anywhere on campus.
Keywords: computing, innovative curricular, entry-level courses, multi-disciplinary design, distance learning, optical fiber, Ansys, Matlab, web pages
The techniques described here were developed at New Mexico Tech, a small research University that began in 1889 at Socorro, New Mexico, USA. New Mexico was a territory then and did not become a part of the USA until 1912. New Mexico Tech shares a history with the University of Ostrava, because both were founded on mining. Over a hundred years ago, silver and lead ores taken from the nearby Magdalena Mountains were processed at three smelters in Socorro. The New Mexico School of Mines was created there to educate mining, metallurgy, mechanics, geology, and chemistry students. In 1951, the name of the school was changed to the New Mexico Institute of Mining and Technology. We often call it New Mexico Tech or just Tech.
Today, Tech has about 1150 undergraduate and 256 graduate students in science and engineering. The engineering majors include chemical, electrical, mechanical, environmental, materials, metallurgical, mineral, and petroleum. The New Mexico Bureau of Mines and Mineral Resources, the Petroleum Recovery Research Center , Langmuir Laboratory for Atmospheric Physics, and EMRTC, the explosives-research center, are also part of Tech. An aerial view of the campus and M Mountain where the explosives research is performed, are show in Figure 1.
Figure 1. The New Mexico Tech campus
New Mexico Tech entered the computer age in the 1960s with an IBM /360 computer that had less than 100 Kb of memory. Then, in the 1970s, we changed to a network of Sun workstations. In the 1980s, microcomputers appeared beginning with the Altair 8800. (This computer was made by MITS and supplied with programs by Microsoft, two new companies located in nearby Albuquerque.) Programming with the Basic computer language and printing out the answers on a Teletype machine, our engineering students were solving problems that were impossible or very difficult with slide rules and log tables that were in use at the time. A Novell network of PCs was added in 1994, which allowed dual booting of either Linux or Microsoft Windows 3. Since 1997, the computer-center PCs have been controlled by the Sun file servers and Windows 95 was installed. We expect to convert to Windows 98 soon.
Our campus now has 30 Sun workstations and several hundred PCs that are connected by Ethernet and fiber optics. Our offices and laboratories, as well as the dormitories, are also networked with optical fiber. Most of our new engineering students arrive with their own PCs and so they are ready to begin engineering computing.
Because I live on campus, my home is served by a wireless network connection that runs at 1 Mb/s. Thus, I have integrated computing into my life as well as my classes. My students regularly ask for help with homework and other assignments by e-mail. Since I am on-line about 17 hours a day, they can often get answers in just a few minutes. I am trying to get other faculty as interested in computing as I am.
We have been introducing computer programming into engineering classes over the years, with some success. Naturally, we started with the Fortran language and then moved on to Pascal. In 1993, as we were considering methods to increase retention of engineering students and to improve our engineering education in general, the author participated in a National Science Foundation workshop on The Introductory Engineering Experience. As a result of this workshop, we created two entry-level courses for engineering students. These two courses replace three previous courses and add new material as well. In addition, students must pass a computer readiness examination to show that they are already familiar with the operation of a PC and Microsoft Windows before they can take the new courses.
The first course, Introduction to Engineering, teaches basic engineering structure and problem solving. It also covers such topics as:
The second course, Computer Programming for Engineers, develops problem-solving skills using the computer language called Matlab. This course combines a teaching of engineering programming with the solving of engineering problems. During the laboratory, each student uses a networked PC running Windows 95. However, since most students own a PC and receive a student version of Matlab as part of the course, they can continue the laboratory exercises outside of class.
Matlab is a vector language that is particularly suited to solution of engineering problems. The syntax closely follows the method engineers use to solve problems and it is very easy to plot the data. For example, a vector time can be defined as integers from 1 to 9 with the statement:
time = 1:9
while a two-by-two array called stiffness can be created either on one line using semicolons:
stiffness = [ k11 k12; k12 k22]
or on two lines in the usual shape. As another example, an array of polar moments of inertia, j, can be defined on one line with the expression:
j = pi/32*(diao .^4 - diai .^4)
Here diao and diai are, respectively, arrays of the outside and inside diameters and the symbol pi is predefined in Matlab.
Our next step introduced meaningful computing into the other engineering science courses, especially statics, dynamics, and strength of materials. Matlab is the programming language in these courses, too. The assignments are generally adapted from problems given in the textbook. Eight of the computer assignments are available on my web pages starting at http://www.nmt.edu/~armiller/problems.htm.
For example, one of the problems assigned in the Statics class is adapted from Beer and Johnston (1). The problem is to calculate the angle of pending motion for two blocks, one on top of the other, resting on an incline and connected by a cable passing over a pulley. The problem is defined at the web site http://www.nmt.edu/~armiller/301frict.htm, which shows a plot of the results. The plot is reproduced in Figure 2.
Figure 2. Matlab plot of incline angle vs. weight
My Finite Element Analysis and Design course (FEA) began modestly in 1987 and has developed steadily over the years. Since there are several commercially available FEA packages, we do not attempt to write such a program. Instead, the course winds its way between principles and practice. We solve simple structural and heat-transfer problems by developing the fundamental equations and then solving them with Matlab. The solution is checked by also solving the same problem with Ansys, a popular FEA package. There are about 100 web pages for this class that are reached from the class home page located at http://www.nmt.edu/~es421/.
One of the class web pages links to prototype files in Matlab and Ansys (http://www.nmt.edu/~es421/files421.htm), while another links to the laboratory assignments (http://www.nmt.edu/~es421/assign.htm). For example, one problem is to determine the displacements and stresses in a square plate with a hole in the center that is loaded on opposite edges. Because of symmetry, only one-quarter of the plate is needed for the model. The displacement and stress graphics created by Ansys are shown in Figures 3 and 4. Additional web pages provide help for Ansys and Unix, because we run Ansys on Sun workstations.
Figure 3. Deflection in a Plate with Hole
Figure 4. Stresses in a Plate with Hole
There is also a term project that requires each student to design a unique set of bridge trusses. The stresses and deflections for each element are determined with Ansys. Then, using Ansys, each element is resized to produce the design stress.
We want our engineering students to broaden their perspective by participating in multidisciplinary design. Two examples of this are the design of robots and the design and operation of our solar racecar. As is common today, our engineering students take two years of design classes. The major content of these courses is directed toward the practice of engineering design and the ethical, economic, and societal issues, which are part of the engineering profession. The experience of working in design teams is also important. There are weekly, intensive workshops in specialized topics pertaining to real design projects. Junior-level students work in teams under the direct management of the faculty members and the senior-level students assigned to each project. Tasks include:
When electrical engineering students initially designed robots, there were often mechanical problems such as the arms falling off. It was clear that cooperation between electrical and mechanical engineering students could produce a better product. Therefore, the prerequisites for the robotics course were changed so that mechanical engineering students could enroll, too. Since then, the robotics classes have attracted students from both disciplines.
A more involved project is the design of our solar racecar for the biennial Sunrayce competition. Intercollegiate teams from North American universities design and race vehicles powered by the sun. The race covers 1300 miles (2100 km) over a period of ten days. The 1997 race went from the Indianapolis Motor Speedway to Colorado Springs and the Tech team finished 21st in a field of 36 cars. The 1999 race runs from Washington, D. C. to Epcot Center at Walt Disney World near Orlando, Florida.
Working together through their design classes, electrical, mechanical, and materials engineering students built a new version of the solar car for the 1999 race. Separate design teams worked on:
The chassis of the racecar is made of carbon fiber and kevlar. A finite-element model of the racecar shown in Figure 5, helps design a vehicle with minimum drag. The body and suspension are shown in Figure 6.
Figure 5. Finite-element model of the solar racecar
Figure 6. Carbon fiber and kevlar body of the solar racecar
Convenient and rapid communication for students and faculty is possible because our campus offices, laboratories, and dormitories are connected by high-speed links. As mentioned above, we also have a wireless system, which provides high-speed Internet connections for computers located remotely in the field or in unwired buildings. With our high-speed connections, the author’s many web pages devoted to assignments and general guidelines are readily available to students. Furthermore, the computer center is open until midnight during the week.
There are three New Mexico State universities and two U.S. Government laboratories located along the Rio Grande over a distance of about 300 miles (500 km). The organizations are:
Regular college courses are transmitted by optical fiber among these five organizations. This allows students to take courses that are not offered by their institution and it allows government lab employees to further their education.
Some of our laboratories are fitted with computers that can control and monitor experimental equipment. The results can then be fed into the Internet so that the experimental data may be observed anywhere on campus. For example, our fluids lab has eight identical stations that can control and measure flow-rate, temperature, and pressure. The 16-channel analyzers can make 100 000 readings/sec. Labview processes the data and can create tables and plots, and then store the data on disk.
For many years, we have been increasing the computer capabilities of New Mexico Tech. Currently our offices, dormitories, laboratories, and computer center are interconnected. We have introduced computer assignments into many of our engineering science courses. Students and faculty can communicate by e-mail while class assignments and additional information are available on web pages. We are becoming a closely knitted organization.
1. BEER, Ferdinand P. and JOHNSTON Jr, E. Russell. Vector Mechanics for Engineers. New York: McGraw-Hill, 1996, 6th ed. 600 Pages. ISBN 007-844193-5.