Can invention be taught? The only way to find out is to try Again, apprenticeship with a master inventor would be ideal. One way to have students experience science and engineering in-the-making is to have them apprentice with mentors--working scientists and engineers. It would be great if we could give significant numbers of students the opportunity to work with Alexander Graham Bell, or Susan Lyons, or Al Rich. Barring that, we can create a kind of virtual apprenticeship via the use of active learning modules, where they are confronted with open-ended problems like designing a portable shelter for the homeless; to solve such problems, they will have to conduct original research and build prototypes .
Like a module based on the first electromagnetic motor, a module based on the telephone would involve hands-on activities that are within reach of most students, even those without strong technical background. Readers of Chapter 3 will remember that most of Bell’s experimental devices were made out of simple components, in part because of his lack of electrical knowledge and in part because of his limited resources. Elisha Gray and Thomas Edison built more complicated devices but some of their principles can be adapted by students, e.g., Edison’s use of carbon as a resistance medium.
Bell's case is suited for science education as well as invention because he tried to be scientific in his approach. At the same time, his knowledge of mathematics was limited, so his process is accessible to students from a diversity of backgrounds. Modern students can reconstruct Bell's experimental prototypes using modern batteries, wire and magnets, though reconstruction is no guarantee that they will see the underlying theory. Bell also left extensive records, so students can compare their experiments and results with those of the master.
Vicarious mentoring is facilitated by the fact that Bell’s notebooks are full of his own reflections on his problem-solving efforts. Donald Norman distinguishes between experiential and reflective cognition. The former is exemplified by the expert in a domain, who does not need to reflect--the 'obvious' solution emerges from her experience. The latter is exemplified by the expert moving into a new domain, where her previous experience does not produce a solution; she will have to reflect on her problem-solving strategies and ways of representing the problem in order to come up with a new way of reaching her goal. Indeed, as a result of reflection, the goal itself may change. Bell's primary area of expertise was in speech and audition; for him, electricity was a novel domain, and as a result he reflected constantly on the best way to proceed. Students can see this reflection and learn from it, because they are in a similar situation--thrust into an unfamiliar problem area, and asked to come up with a novel solution. As note, "if the eventual objective of instruction is to provide the additional capability to flexibly adapt various forms of thinking when they are appropriate, then it is important that instruction not end precisely at the point where it should begin. All science teachers can tell anecdotes in which the classroom demonstration is completed, and two weeks later children recall the 'magic effect' but not the associated principle...interest in generating effects may help engage children in the reasoning process, but sustained effort is required for progress beyond that to a model of scientific inquiry oriented toward achieving understanding" (p. 878). The best discoverers and inventors are those who engage in the 'sustained effort' of reflection, improving their group or individual approaches to novel problems.
When I created a module based on the telephone, I had three major goals:
(1) To permit students to compare their own invention processes with those of a master inventors working on the same problem. Students' reference materials included sections from Bell's notebooks, his original patent, Gray’s caveat, and additional material which we put on the Web (http://repo-nt.tcc.virginia.edu/classes/tcc315).
From this kind of virtual apprenticeship, I hoped students would learn the following skills:
(a) how to keep an invention notebook
(b) how to reflect on, and modify, one’s own invention process
(c) how to write a patent
(2) To encourage students to experience the invention process first-hand, from idea to device to patent, thereby increasing their appreciation for the way in which human beings have transformed the world we live in.
(3) To promote the idea that invention is not mysterious, that it can be studied and taught.
In their packet of materials, students read the following problem statement:
You will enter the competition between Bell and Gray as a third party, similar to Edison whose Menlo Park team succeeded in making a major improvement on Bell's invention. Your goal is to design an improvement or variation on the Bell and Gray devices that you will first caveat, and then try to patent. You will also have to build and demonstrate an actual device that illustrates the claims in your patent.
In order to establish that your invention is independent, you will have to demonstrate that even though you are aware of the Bell and Gray materials, your invention goes significantly beyond them. In order to do this, you will have to document your processes, and be ready to describe them in detail. The bolder and more innovative your approach, the less likely anyone can argue that anyone versed in the art of the time could have done the same.
Because the increasingly cooperative aspects of scientific discovery and invention are well-documented students were assigned to groups of three or four to work on the telephone module. This meant that the module could help fulfill an additional important goal: teach students how to work in teams, a goal that is receiving increasing emphasis in engineering education. For example, the new "Engineering Criteria 2000," which will be used to accreadit Engineering programs, allows students to be able work in multi-disciplinary teams .
In a book on using cases to teach Pascal, Michael Clancy argued that, "Using case studies, students help design solutions to problems they could not solve alone. The concepts of design are illustrated in the context of large complex programs where these ideas make sense. The case studies engage the student as a team member who contributes to the program design. Students learn aspects of design that apply to real-world programming where teamwork is prevalent" .
We were careful to mix majors in groups, though a stronger approach would have been to mix cognitive styles, as well. Two of these styles, for example, are visual and mathematical. During the development of quantum mechanics, Heisenberg developed a purely mathematical formulation of the way in which electrons changed orbits. Schrodinger’s developed a visualizable alternative formulation "based on a wave imagery of electrons in which atomic transitions were continuous and visualizable like the transitions between the vibrational modes in a drumhead" . Similarly, Freeman Dyson showed that a visual approach by Feynman and a mathematical approach by Schwinger were formally equivalent . The point is, either visual or mathematical cognitive styles could lead to discoveries on these sorts of problems.
Howard Gardner has identified other kinds of cognitive styles as well, including verbal and kinesthetic . Watson, for example, had a kind of kinesthetic style--he was best at building Bell’s ideas. An optimal invention team would have a mixture of styles: a good visualizer, to draw and imagine, someone who liked to write, to keep the notebook and do the patents, someone who liked to build and someone who could work through the mathematical implications of Ohm’s law. I tried to get some kind of balance among styles by making sure the majors were mixed and telling group members to utilize multiple talents--an English or Art major could be as useful on the telephone module as an Electrical Engineer.
Each group was allowed to select what it needed from a set of simple materials, including batteries of different voltages and several types of wire. Students were also encouraged to scrounge for materials like cans and nails, but they had to submit a proposal before purchasing any equipment. Their objective was to patent an electrical communication system potentially capable of working over long distances which:
(1) could transmit information rapidly and cheaply.
(2) represented an improvement on Bell's design, and those described in other materials the students were given in their packets. These materials included Gray’s caveat.
In short, it would not be enough to build a replica of Bell’s telephone; students would have to patent an improvement. The written and oral assignments for this module were structured around the patent process. Students first prepared a caveat, a document used in the 19th century to signal an intention to test and perfect a new invention. (The patent office now allows prospective inventors to file a disclosure document that fulfills a similar function). Students are given Gray's caveat for a speaking telegraph as an example to study (see Chapter 3).
The caveat allowed students to signal the direction of their research. Students gave oral presentations of their caveats to the instructors, outside experts and their classmates, and demonstrated a prototype of the device they hoped to patent. After receiving feedback on their caveats, students began the testing and revision necessary to transform a caveat into a patent. They had Alexander Graham Bell's telephone patent as an example, along with detailed instructions on preparing a patent. Their patents were presented to the class and an outside judge, usually a patent examiner, who decided which claims were worth granting. Students also submitted a written patent. In addition, students kept group and individual notebooks which included both details of their invention processes and comparisons with the work of actual telephone inventors.
This module emerged out of my desire to derive an educational pay-off from my research on the invention of the telephone. It wasn’t clear how such a module would fit into the required courses that I taught, so I invented a new course.
The process of inventing this new course modeled the process I would take students through, except that instead of a caveat, I built a team and wrote a grant proposal to the Leadership Opportunities in Science and Humanities program, a creative effort jointly funded by the National Science Foundation, the National Endowment for the Humanities and the Fund for the Improvement of Post-Secondary Education. This program funded development of the course and its initial evaluation. There were design courses in Engineering and Architecture at the University of Virginia, but nothing on invention. I made it clear we would recruit students from a variety of majors; to make this easier, I was able to get the course cross-listed in psychology.
My three co-teachers were Larry Richards, a psychologist who specialized in design and manufacturing; Bill Scherer, a systems engineer who was an expert at supervising complicated team projects and Julia Pet-Edwards. Each of us agreed to do a module, but also to try to attend each others’ modules, so this would be a real team-teaching experience. My module was the telephone, the first one the students did. I also took over the job of coordinating the class, with our teaching assistant, Julia Kagiwada. Our two consultants, Eric Bredo and W. Bernard Carlson, provided valuable expertise in the areas of educational evaluation and history of invention, respectively.
We intended the course as a kind of teaching laboratory for trying out new ideas. For example, the first time we offered the course, I piloted my rough ideas for a telephone module, refining them as we went along. We attracted 18 students: seven in their fourth year, seven in their third, three in their second and one in her first. There was a broad distribution of majors, with eleven students from a variety of Engineering disciplines and seven from liberal arts, including three from Psychology and Cognitive Science, and one from Architecture. Therefore, some students had extensive technical and mathematical backgrounds, while others had much less. The male/female ratio was roughly 60/40.
The breadth of student backgrounds was excellent, from our perspective; we wanted the modules to be usable in a wide range of settings. To accommodate differences in background, we placed background readings on reserve (see http://repo-nt.tcc.virginia.edu/classes/tcc315) and sent students with specific questions to these sources. We also carefully balanced expertise within groups, so that a political science student might be working with an electrical engineer, a chemical engineer and a psychology major.
We have since offered the course four times. We have not always been able to maintain this kind of student diversity; there were semesters when we had almost all engineering students, and then the course did not go as well, because the engineering students needed to be challenged by students who did not share their disciplinary paradigms and exemplars.
The best way to understand what students learned from the telephone module in this course is to follow the method we have used throughout this book and look closely at a fine-grained case study.
Consider, for example, one of the groups in our most recent iteration of the Invention and Design class. Initially, this group, which included a third-year Cognitive Science major a third-year Computer Science major, and a fourth-year Systems Engineer, had to choose between three major alternate paths, as shown in Figure 3. Two paths were ones actually used by Bell, who developed a liquid transmitter (see Section 3.9.1) and also a device called the photophone that translated light into sound. Students were also given information on a carbon transmitter developed by Thomas Edison .
This group elected to work with Bell's photophone, on the grounds that it had the most room for improvement, resembled modern ideas like fiber optics and might be easier to manage than messy liquids and ground carbon. Their initial information about the photophone came from a brochure describing a December 1976, exhibit at the National Museum of American History entitled "Person to Person"; page 6 showed how one could build a simple photophone using a flashlight, a tin can, a solar cell and a couple of batteries (see http:repo-nt.tcc.virginia.edu/classes/tcc315/alm/telephone/exhibits/build.html). They could also look at examples from previous classes; several groups had tried to improve the photophone, with varying results. I encouraged students to build off the work of previous students, whenever possible, treating the earlier student work as part of the ‘state of the art’ they would have to go beyond.
This group knew they had to treat the "Person to Person" exhibit as part of the state of the art; they would have to improve on it. But it did suggest how to use modern materials to achieve Bell’s goal. The group decided to build and test a photophone in which a paper cup served as the speaking tube, with a piece of plastic serving as the membrane. To this they attached a piece of a compact disk, which served as the mirror; a beam from a flashlight bounced off this mirror onto a solar cell. When they spoke into the cone, they hoped the mirror would vibrate enough to cause that famous undulating current of Bell’s to emanate from the solar cell. They decided their major innovation would involve the use of magnifying glasses to increase the intensity of light reaching the mirrored surface and the solar cell. Figure 19 shows this design.
Figure 19: First design by a group trying to improve on Bell’s photophone in an invention and design class.
The initial arrangement caused a small fluctuation in the needle of a multimeter when someone spoke or blew into the cone. I told groups that they could use a multimenter to test the effectiveness of their designs. Bell, of course, did not have this kind of tool available to him, but he did use crude galvanometers of various sorts. The fluctuating needle suggested that this group’s photophone might indeed be producing an undulating current, albeit a weak one.
The group was concerned that this marginal effect might be due to ambient light and instability in the set-up. Like Bell, whose processes they were studying as the worked, the students focused on slots in their mental model that seemed especially likely to improve the quality of transmission. Initially, they worked in a reflection slot, trying to accentuate the fluctuations in the light by substituting a variety of reflecting materials. The most promising result was obtained with a piece of a CD. Then they experimented with the way in which the reflector was mounted, attaching it to the can with rubber bands and finally mounting it on a rubber membrane. They also came up with a kind of container slot, enclosing the apparatus in a cheesebox in an effort to stabilize it and minimize outside lighting. This set of changes produced a positive result, though students were careful to note that some of the fluctuation might be due to factors other than the voice.
Overall, the group concluded that there was still too little fluctuation. They worked for a while in a magnification slot and found that still did not make a significant improvement. Despite their reservations, they had to submit a caveat, signaling their intention to invent a photophone, and they felt the design still had potential. A real inventor would not have to submit a caveat before it was quite ready, but would be under enormous pressure to submit as early as possible.
I had a former student, Greg Morse, who was a patent examiner, come down and review the students’ caveats. He brought with him a copy of Bell’s original photophone patent. The group discovered that their main claim to novelty, concerning the manipulation of magnifying glasses, was also claimed by Bell and therefore was part of the state of the art.
The day Elisha Gray submitted a caveat for a 'speaking telegraph' he had an experience similar to this student group: he learned that another inventor, Alexander Graham Bell, had just submitted a patent covering spoken transmission. The patent office declared that Gray's caveat and Bell's patent were in interference, meaning that Bell could not be granted a patent until it was clear that his claims were either prior to, or different from, Gray's. Bell learned from the patent examiner that the point of interference concerned a clause Bell had inserted at the last minute in which he claimed the possibility of using variable resistance to create an undulating current. Elisha Gray had featured a variable resistance transmitter in his caveat, and Edison would base his successful carbon transmitter on the same principle . After several weeks, the interference was declared invalid, on the grounds that Bell's patent had arrived in the office earlier. But Bell's conversation with the patent examiner may have suggested a change in his research direction and led to his first experiments with the liquid transmitter (see Chapter 3).
The students in the photophone group had to make the same kind of change in direction after they submitted their caveat, revising their original intentions in the light of their interference with Bell's actual photophone patent. They decided the solar cell simply could not detect the small vibrations of a mirrored surface. Instead, they removed the reflection slot altogether and they tried shining the light directly on the cell, jiggling it and varying its intensity. The most positive results were obtained when the intensity of the light was changed, rather than when it was merely vibrated.
They now had a new goal: to "find some way to vary the intensity of the light rather than just vibrating it." They brainstormed, then hypothesized "that somehow the vibrations of the membrane could be used in a circuit to intermittently open and close the circuit. This should cause the light to flash in a pattern corresponding to the vibrations." They were considering what Bell called an intermittent current--a succession of on-off pulses. Bell's first telephone patent described why such a design would not work--why one needed an undulating current instead. The group apparently did not recall Bell's analysis, and plowed ahead. This point in the photophone group’s process was described by a member as follows:
Many times, the inspirations for what can later be seen as a breakthrough come from changing the perspective of your efforts. In this case, when confronted with the Bell patent obstacle, we had to change our entire focus. ‘Stepping outside of the system’ could be a good way of describing this action. We had to step out of the ‘classroom’ system which we following in thinking that this was an assignment, and not an actual ‘inventive process’. We also stepped out of the ‘historical’ mode, and looked at our problem form a modern, multi-disciplinary vantage point.
To approach this goal, the group created a new contacts slot that resembled one Bell had created in his March 8th experiments with the liquid transmitter (see Chapter 3, Figure 17). They began a series of experiments in the contacts slot, beginning with a device that included a piece of aluminum foil on the membrane that was connected to the negative lead on the battery by a length of solder. The solder was put as close as possible to the foil without touching it. They tested this arrangement by shouting "Testing, 1, 2, 3" into the mouthpiece, and obtained a negative result, which they attributed to the fact that the foil was not rigid enough. So they replaced it with a tack pointing upwards, which made enough contact with the solder to cause the light to shine, but not enough to activate the solar cell. This was a somewhat positive result, promising enough to suggest that their current goal deserved further pursuit.
But it did lead to a change in their hypothesis. Instead of making the light flash on and off, they decided to let it stay on. Now they were back on Bell's idea of creating an undulating current, in this case by somehow varying the intensity of the light source. They found that the vibrations of the membrane caused the light intensity to fluctuate, but not enough to affect the readings from the multimeter.
They hypothesized that if the two contacts had more surface area, the signal would be improved (see Figure 20). They tried two tacks, with their flat surfaces facing each other. They then achieved a dramatic positive result: "a seemingly nice, reproducible fluctuation in light intensity was made. On checking the resistance of the solar cell (and thereby the current) we saw that resistance did change proportionally to words spoken into the mouthpiece." Similarly, Bell’s first telephone had not produced distinct speech sounds, but a mumbling that Bell treated as a positive result--so positive that he went to patent on the basis of it.
Figure 20: Final design of a student group improving upon Bell’s photophone. Scanned pictures are from the group’s notebook.
The group then moved to stabilizing this arrangement, adding features like a platform that would make their experimental set-up into something more reliable. I permitted students to hook their devices into modern amplifiers and tape-recorders for demonstration; using the latter, this group was eventually able to obtain a scratchy recording of speech. They also produced a patent, which included the following summary of the design:
In response to sound sent through a cylindrical mouthpiece, a diaphragm stretched over the opposite end of the mouthpiece vibrates. This undulation alters the flow of current between two closely spaced metal contacts, one of which is attached to the taut diaphragm. When touching, the two contacts complete a circuit containing a light and power source. The intensity of the light depends upon and fluctuates with the amount of current supplied to the light source. These variable emissions from the light are received by a means for transforming solar energy to electrical current. The means for transforming has analog output based on the variable intensity of the light. This output can be sent to a generic receiver.
This detailed account of one group's progress shows the way in which students' invention processes can parallel those of a historical inventor, but still be original in important respects. For this group, there did seem to be elements of virtual apprenticeship. They were not explicitly aware of the close parallels between their invention processes and Bell’s, but the way in which they systematically experimented in slots and re-discovered the importance of the undulating current suggests a tacit influence. Similarly, student teams could learn different patterns and styles from other scientists and inventors.
This group was not typical--indeed, there was no such thing as a typical group. Other final designs included a system that coupled a carbon transmitter with a photophone which amplified the signal, the combination of a resonant chamber with a carbon rod, which acted as a sliding resistor, several variations on the liquid transmitter and on transmitters that worked by electromagnetic induction. Not all groups followed processes that resembled Bell’s; many tried to take short-cuts by hacking together an initial prototype and sticking with it, even when it didn’t work very well. Students do not have the commitment of an inventor; therefore, many are not motivated to study the invention process in detail and follow it through all the unavoidable twists and turns.
Overall, students in the course learned:
(1). How to work in groups--particularly interdisciplinary groups. There was a kind of 'culture clash' in the Invention and Design class, which drew from two populations--students in a school of engineering and students majoring in other fields, including psychology, cognitive science, and architecture . In the latest Invention and Design course, several students commented that the engineering students were more bottom-up in their approach, whereas the students from outside of engineering were more top-down. Students from fields like mechanical and electrical engineering were more likely to jump into building a working device, while non-engineering students were forced to take a larger view of the project, trying to figure out the overall goals. This difference was far from universal, however; the course attracted a large group of systems engineering students, who were trained to adopt a top-down approach. As groups worked together, disciplinary stereotypes gradually disappeared and were replaced with a recognition of the advantage of taking multiple perspectives on a problem. The photophone group described above provides an example of the kind of close, multi-disciplinary teamwork that could emerge.
One-third of the students in a recent class emphasized that learning the strengths and weaknesses of individual group members and allocating work accordingly were two of the most important things in successful group work. Open communications and respect for group members were also considered extremely important in group work by the students. One student summed it up: "Every group is different, one person can radically affect a dynamic, delegation is important, but communication of expectations and ideas is most important."
(2). How to invent:
By the end of this module, students knew how to keep invention notebooks, write caveats and patents and revise them, based on comments from an examiner. They also knew how to build a prototype and demonstrate it. Naturally, some students acquired higher proficiency at these skills than others, but all experienced the invention process, first-hand.
We also tried to instill wisdom by asking students to reflect on their own invention processes and compare what they did with Bell and Gray. The photophone group described above is a good example of how students could unpack their own processes.
Comparison with the inventor was hardest, as the photophone group again illustrates. They followed a process very similar to Bell’s, but were rarely conscious of that fact. I had to point out the similarities, in order to make them explicit. I did the same for other groups. I wanted them to see that they were adopting one style of invention; they could also study and follow the styles of other inventors. Bell, for example, was very verbal, adopted a conservative focusing heuristic and worked with one collaborator. I also talked about Edison, who was much more visual and kinesthetic than Bell, preferred a focused gambling heuristic and ran the first real R&D lab at Menlo Park. That’s how Edison could afford to be a gambler; he could have members of his team construct several very different prototype telephones at the same time, and compare them.
I thought this kind of active learning module might inspire secondary students to take a greater interest in invention before they had decided on majors and made career choices. With support from the Geraldine R. Dodge Foundation, I set up a summer course for gifted students from 9th through 11th grades, collaborating with two colleagues in the Education school and a high-school physics teacher, who agreed to run the class .
Using student test scores, responses to essays, and teacher recommendations, we selected 15 male and 16 female students entering grades nine through eleven to attend each of two three-week sessions. One-quarter of the students were from ethnic groups traditionally under-represented in technical fields.
The university course lasted for a full semester. The summer enrichment course lasted for only three weeks. (It was given twice, with sixteen students in the first iteration and fifteen in the second). But in the former, students were distracted by dozens of competing assignments, whereas in the latter, their sole focus was this course. In the former, we had grades to motivate students; in the latter, we had to rely on their intrinsic motivation and whatever inspiration we could give. We planned the telephone module to last for about ten days.
The students were eager and enthusiastic on their first day of class. They were immediately faced with a challenging set of materials similar to those I used with university students in my invention and design class, including detailed information on the challenge they would face, samples from Bell's patents and notebooks, and a workbench covered with batteries, wires, containers of different shapes and sizes and other materials they could use as they tried to create an improvement on Bell's patent (for a complete set of these materials, see http://repo-nt.tcc.virginia.edu/~meg3c/id/id_sep/id_sep.html).
As with the college course, when we assigned students to groups, we tried to achieve diversity as much as possible. We mixed students according to sex, and ethnic background. Over one-half of the students were from groups traditionally underrepresented in science and engineering, so we were able to achieve good diversity on that dimension. We tried to infer learning styles from short essays the students had written to get into the program, looking for evidence of interest in mathematics, writing, building, and/or drawing. We tried to balance these indicators of different styles within groups.
The group experience was probably the most difficult and yet rewarding for the students. Most had the confidence that comes from considering themselves gifted; many were used to being the leaders in their groups in school. But now each talented student had to work closely with at least two others who were different in important respects, all of them collaborating intimately because the task was far too complex for any student to complete on his or her own. Students learned that invention is a process that requires numerous abilities or talents (e.g., building, sketching, writing, public speaking) and is enhanced by the engagement of persons exhibiting a variety of intellectual skills and styles.
The classroom was often noisy and chaotic. At any given time, one group might be building a prototype, while another group argued about who should do what. In a third group, only one student might be working while the others appeared to daydream and disengage from the task. We quickly found that we had to play an even more open role than teachers in traditional guided discovery experiences . In guided discovery, the student knows the goal of the activity. But in our case, we could only tell them when they were violating basic principles of physics and supply them with examples of similar designs completed by 19th century inventors. We could never be sure whether a particular alternative would work -- we had to wait breathlessly with the students to see.
Despite--or perhaps because of--the absence of grades or other contingencies, most groups rose to the challenge. One group successfully demonstrated that they could transmit speech using a photophone, a result that was as good as that achieved by the university group described above. The secondary students relied on the mirror approach favored by Bell and did not include the innovations in the contacts slot done by the college students; nonetheless, their final device worked as well. They achieved this result by careful and systematic testing of each component. One female student was the leader, but eventually, with our help, all group members became involved in some aspect of the task. For example, one member who distanced herself from the group throughout much of its activity showed initiative when it came time to write the patent. As facilitators, we spent much of our time encouraging groups to take advantage of the talents of all members, especially groups with a strong leader who tended to want to do everything her or his way.
In another group, the three students had trouble interacting from the second day of class. By the end of the first week, a communication barrier had grown between the two male students and the one female. For example, in a discussion following the film Mosquito Coast and other movies about inventors, one of the male group members noted that in many of the films the inventor was male, was seeking to satisfy a dominant father figure, and was driven by a dream. He continued by saying that the female group member could have definitely filled that role as an inventor, especially since she had such good ideas. But she perceived this as an insult, while the course instructors felt that the male student was attempting to give her a compliment.
At the beginning of the second week, each group conducted a "group progress discussion" in which they went over disagreements like the one above and tried to learn how to communicate better. As a result, the members of this group felt they "worked out" many of their problems, and they did not perceive any major difficulties during the remainder of the telephone project or the solar energy project that followed.
On the telephone module, they began with the idea of a button the speaker could press that would open the listener's phone and fire a bagel at her. This playful, silly idea actually got them involved in thinking about multiple telegraph circuits. Next, they considered having the speaker press a button to display a sign to the listener: a smiling face, or a frowning face, or a heart. The group sketched a workable circuit to implement this design, but abandoned it for a more conventional telephone transmitter, in which a coil would be attached to a diaphragm and move through a magnetic field. Individual group members appeared to contribute equally to the telephone project, with each person working on all aspects of the project design, construction and trouble-shooting.
Not all groups were successful. One group spent much of its time designing an elaborate phone with an elongated speaking tube. When they demonstrated it in front of the class, it worked poorly, and they had trouble describing how their design was an improvement over Bell's patent. The embarrassment of failing so conspicuously in front of their peers drove this group to work harder on the second project, which we will discuss later in this chapter.
Many of the final designs resembled those created by historical inventors. For example, one group put their diaphragm between two transformers without realizing this design closely resembled a polar relay Bell tried to transform into a telephone transmitter. Many of the problems encountered by students also resembled those encountered by inventors. For example, one group came up with a design that resembled one of Edison's in which the vibrations of a diaphragm compressed carbon, thereby alternately increasing and decreasing the current. They found that the carbon gradually lost its friability, and the current no longer changed. Edison had a similar problem; he eventually created a compact carbon button which he put right on the diaphragm . These instances of re-invention suggested, again, that students were experiencing a kind of virtual apprenticeship.
I was concerned that these gifted secondary students would see the telephone as an antiquated technology and conclude that any lessons they learned from building it would not apply to modern inventions. Therefore, I invited Duane Bowker, one of the inventors of TrueVoice at Bell Labs, to come talk to my students. Duane Bowker is one of the inventors of AT&T TrueVoiceSM. The following is an excerpt from an AT&T hand-out provided by Duane describing his invention:
AT & T TrueVoiceSM is a method that greatly improves the quality of long-distance transmission by a) selectively amplifying lower speech frequencies to compensate for the low frequency attenuation introduced by typical telephone transmitters and receivers and (b) increasing the overall loudness of the voice to a level more typical of local telephone calls. The low frequency emphasis makes the person's voice over the telephone sound more like the way that person's voice would normally sound in a face to face conversation. The low-frequency emphasis, in essence, widens the bandwidth of the end-to-end telecommunications channel at the lower end of the spectrum where many talkers have significant amounts of speech energy. The increase in overall loudness makes the speech easier to hear on long distance connections and brings the speech level of typical talkers much closer to that which is considered optimal by most people. The loudness compensation is only applied to softer connections and will not make already loud connections too loud. (http://repo-nt.tcc.virginia.edu/classes/tcc315/alm/telephone/advice)
At Bell Labs, where Duane Bowker works, every successful project eventually becomes a team effort. Duane created the idea for TrueVoice with his colleague, Jim James. They knew each other well, had worked together for a long time, were both cognitive psychologists, and did not need to divide labor. But when it came time to implement the idea, Duane became the product champion--he sold the idea to the rest of the company and helped organized the teams that took a rough prototype and turned it into a new technology. For example, Duane and Jim initially thought that the way to improve transmission was to work with the transmitter and receiver, but a group working on long-distance lines convinced them that was the place to make improvements, and then set about doing it.
Duane discussed the importance of keeping an invention notebook. AT&T owns his, and keeps it under lock and key. He also noted that he and his colleague had received several patents, which were held by AT&T. He was very careful not to tell us too much about how the technology was developed; hence the hand-out, which had been cleared by the company.
What he did talk about was how to work in teams, information that was especially salient for the secondary gifted students, who were not used to working together on projects of this complexity. Duane talked about six aspects of team invention.
(1) Goals: Typically, a group project begins with a set of goals like the ones described in the packet the students were given at the beginning of the telephone module. However, the goal is usually very general and leaves room for innovation. In Duane’s case, the goal was to selectively amplify low speech frequencies. He and Jim James came up with this goal based on their experience as cognitive scientists; their unique expertise enabled them to identify this as the main problem with distortion over long-distance networks. But this goal could be attained in a number of ways. They started out with improving the telephone and ended-up focusing on long-distance lines, which required experts from other groups at Bell Labs.
In the students’ case, the goal was to improve on Bell and Gray’s designs, which left a wide range of alternatives open. Groups still had to decide which direction to take.
Duane suggested using brainstorming, in which group members write down and discuss ideas without any criticism. No one can say anything negative. Brainstorming creates a climate where people can listen and share freely. My colleague Bill Scherer adds brainwriting to this--writing whatever ideas come into ones head before the brainstorming session, without trying to discriminate the good from the bad.
Eventually, these ideas need to be focused, most eliminated, some combined. Most of the university students found this brainstorming the hardest; they wanted to jump into an immediate solution, to guess the right answer, the way they would in a laboratory exercise. The secondary students were generally more willing to brainstorm, as exemplified by the group that came up with the bagel telephone, above.
There is no handy technique like brainstorming for the winnowing and focusing phase of invention. One benefit of brainstorming may be that it instills an attitude of mutual respect among group members, teaching them to really listen to one another. This kind of atmosphere is more likely to produce the kind of constructive criticism that must follow brainstorming.
(2) Resources: Groups also typically begin with limited resources--in this case, a set of materials. If a group in a corporation like AT&T needs to get more, they have to work together to persuade management. A group that has a strong consensus makes a much better case for additional materials than one where some members don't know what is going on, or disagree with others about the group's direction.
(3) Division of labor: In a bad team, nobody knows who does what. A good team divides the labor into micro-tasks. These tasks should be suited to the expertise and interests of individual members, as much as possible. One of the unrealistic things about the module in the invention classes is that students do not get to select their additional team members, based on expertise. This kind of top-down assignment often happens in companies, but most really creative teams organize themselves. I suggested to student groups that they do an expertise assessment right at the outset, to see what their strengths were. On an open-ended project, they could evolve a design that played to their strengths.
(4) Schedule: Groups often begin with a schedule imposed from the outside, but effective groups also develop an internal schedule that sets goals for the completion of micro-tasks. For example, while two people are building a transmitter, another two can be writing a caveat. Our schedule on the telephone module included only general deadlines, like caveat and patent. We deliberately refused to manage each group’s internal deadlines--they had to generate their own set of smaller steps to achieve this goal. Interestingly, I felt the college students had more trouble doing this, in part because of other, competing assignments that had rigid deadlines.
(5) Rules: Groups often find that they need to set-up a set of rules or guidelines for participation and decision-making. For example, one of the dangers of dividing labor is that an individual working on one part of the device may get out of touch with an individual working on another--and the components will not work together. One way around that is to get the group together at regular intervals and discuss progress. Again, we encouraged groups to do this on their own, giving them advice and help.
(6) Leadership: Having a leader like Duane who serves as a product champion is great, provided the leader listens and makes sure the rest of the team is 'on board'. A group can make it a rule that everyone gets a chance to talk at meetings, to avoid one member becoming too dominant; groups can also pick a moderator who is not the champion to ensure that alternatives are considered, but the discussion does not bog down--one has to make decisions about what to do and move ahead.
An outside evaluator with expertise in gifted education made the following comment after seeing groups present their telephone projects: "[The groups] clearly reflected an understanding of what they had done, its meaning, its reasons--why things work and don't, where their theory falls short of being realized and the steps necessary to span the gap--and the relationship of whole and part. It was clear they have read and heard much complex information which they can translate into practice and that they have a sense of where their inventions are relative to Bell's early work."
Duane Bowker commented that he was "surprised how well some of the experiences the students related mapped onto the way things often go in an existing engineering organization like AT&T Bell Laboratories... The students showed a great deal of insight into the process and team issues their groups ran into. You and I appear to be in agreement that exposing engineering students to these process and teamwork issues, and giving them opportunities to develop those skills that make the effective team participants, can really enhance their long-term career success."
From the telephone module, both post-secondary and secondary students learned more about how to function in design teams and also about how the invention process really works. This knowledge consisted in a combination of information and skills. To help students develop the wisdom to know when and why to apply this new knowledge, I wanted them to have an opportunity to create a new technology of their own. In section 5.5, I will describe a module that tries to accomplish this goal. Before students experience that module, however, they have to work on cases like DesignTex and Dow Corning to understand how ethics is can be integrated into invention and design.
This page was last edited: Wednesday, July 14, 1999