Using Tablet PC and DyKnow in a Mechanics of Materials Course Patrick Ferro, Rose-Hulman Institute of Technology

Abstract

A Mechanics of Materials course was revised to include the use of Tablet PC and DyKnow software.

Classroom assessment techniques were developed to utilize the capabilities of the Tablet PC and DyKnow

software to provide feedback to the instructor. Exercises that worked well included drawing stress

elements and Mohr's circles. The archiving capability of the software allowed students to save work and

in-class examples. Challenges involved in implementing the technology in this type of course will be

discussed.

Key Words

Education Methods, Technology in the Classroom

Using Tablet PC and DyKnow in a Mechanics of Materials Course

Patrick D. Ferro Assistant Professor of Mechanical Engineering

Rose-Hulman Institute of Technology Terre Haute IN 47803

A Mechanics of Materials course was revised to include the use of Tablet PC and DyKnow software. Classroom assessment techniques were developed to utilize the capabilities of the Tablet PC and DyKnow software to provide feedback to the instructor. Exercises that worked well included drawing stress elements and Mohr's circles. The archiving capability of the software allowed students to save work and in-class examples. Challenges involved in implementing the technology in this type of course will be discussed. Introduction DyKnow software and Tablet PC technology were used in two sections of Mechanics of Materials during an academic term in 2007. The course was taught according to a common curriculum, in that topics were covered at the same time on the calendar as they would have regardless of whether the course was taught using DyKnow and Tablet PC. Table 1 lists examples of course topics and examples of how the technology was used to change the instruction. Table 1. Example topics Examples of how DyKnow and Tablet PC were used Stress, deflection Students were asked to derive the deflection equation and

submit a panel Torsion Relationships between shear strain, angle of twist, shaft

length and shaft radius were drawn using several colors; students asked to highlight (in certain colors) each of these

Moment of inertia Students were asked to circle the part of a given calculation that showed where the parallel axis theorem was being applied

Bending stress Detailed example solved problems were screen captured; individual students were called on and asked to circle, in class from their tablet, a part of a calculation

Shear and Moment diagrams Given a relatively simple loading, students were asked to submit panels with V and M diagrams

Shear stress For a given beam cross-section, students were asked to highlight the area used to calculate Q, then asked to indicate (in red) the point on the beam where the shear stress was being calculated

Deflection by integration Polling was used to confirm understanding of boundary conditions

Mohr's circle Students were given a circle and asked to represent a new state of stress on the circle (in a different color)

Thin walled pressure vessel Students were asked to submit panels showing how they calculated the maximum shear stress in any plane for a pressure vessel problem

Beam selection in design Students were asked to indicate on a beam cross-section the highest stress location, and indicate it in color

Examples At the beginning of the quarter, students were polled to assess their general knowledge of DyKnow. The polling feature on DyKnow was used to determine students' knowedge and enthuisiasm for using DyKnow instead of traditional whiteboard teaching methods. Figure 1 is a screen capture from a DyKnow saved file, showing the results of one of the polls from a section. The data shows that 65% of the students self-reported a general knowledge level that was at least ranked in the 'medium' category. The data shown in figure one represents approximately twenty five students.

Fig. 1. Screen capture from a DyKnow in-class polling on general knowledge of DyKnow. The poll was taken on the first day of the quarter. Most students ranked their knowledge level as 'medium' or higher.

Fig. 2. Screen capture from a DyKnow file showing how a poll was used to explain Hooke's Law. The correct answer, 'c', is highlighted. Fig. 2 shows another example of an in-class concept question for which the polling feature was used. The question was asked of the section during the first week of the quarter. The topic was a review of Statics, which was a prerequisite for the course. The question was asked during the first week of the academic year. The result of the poll indicated that 63% of the students (of approximately 25 students that participated) chose the correct answer, using Hooke's Law and the definition of strain. The notes on the slide were handwritten (using a pen tool) after the results of the poll were embedded on the prepared DyKnow slide.

Fig. 3. Screen capture from a DyKnow file showing the results of an in-class poll. The correct answer to the question about the relationship between torque and radius during torque transfer was D, which most students correctly identified. Fig. 3 shows an example of polling to confirm students' knowledge of torque transfer. In the poll shown, seventy-seven percent of the polled students identified the correct answer. The poll was quick, and allowed for the instructor to remind the students about torque transfer and to correct misconceptions for the few students for which a misconception still existed on this topic. The poll was written in syntax, to allow students a modest challenge for a relatively simple question.

Fig. 4. Screen capture of a DyKnow slide prepared by the instructor. The gray box is the students' answer box. The actual solution to the problem is shown to the right of the box. The actual solution is progressively disclosed to the students during lecture, after students have had a chance to work the problem. Fig. 4 shows a typical way in which DyKnow slides were used to encourage students to take notes for which they may possibly consult later. The slide was prepared by scanning the hand-sketched beam loading diagram onto the slide, along with the hand-sketched V and M graphs. The V and M graph solutions were then 'whited' over, so that they would not be disclosed until after the students had sketched their respective answers in the gray answer box. Once the students had drawn their V and M diagram solutions, the instructor erased the white covering over the solution to the right of the gray box, so students could see the correct answer. During the time that the students are working on the solution, the instructor may walk around in the classroom and/or ask students to electronically submit their panels. Fig. 5 shows a panel similar to fig. 4, in that a beam is shown. In fig. 5, students were asked to draw the equivalent beam, and to submit the panel to the instructor for evaluation.

Fig. 5. Screen capture of a DyKnow panel. The panel shows how a gray answer box can be used to prompt students to sketch an answer. The student's panels may be submitted by the students, or accessed by the instructor independently.

Fig. 6. Screen capture of a DyKnow panel, showing how a Mohr's circle type of problem. This type of problem uses many of the strengths of DyKnow, in that note taking and simple sketching are easily performed. Fig. 6 shows a Mohr's circle problem on a screen-captured DyKnow panel. The original panel was prepared by scanning a hand-sketched stress element, with incomplete ordered pairs and a Mohr's circle diagram without the circle drawn. In class, students were asked to fill in the ordered pair values, and to sketch the circle. The state of stress at an angle 50° in the clockwise direction is represented on the Mohr's circle shown in fig. 6.

Fig. 7. Screen capture of a DyKnow panel, showing how the objectives of the lecture were provided each day. Fig. 7 is an example of an introductory panel. The introductory panel was used each lecture day, to let students know what the important topics of the day were going to be. The students were often reminded that it was their responsibility to convey to the instructor if they did not feel like the subjects were adequately discussed or covered. One advantage of providing the objectives of the day is that students who study with the DyKnow notes will be able to quickly organize their notes, to help them save time in preparation for studying.

Fig. 8. Screen capture of a DyKnow panel, showing how panel was used to prompt students to record their own notes. The slide was prepared by scanning a sketch of a pressure vessel, along with the partially-completed definitions for longitudinal and hoop stress. During the lecture, the instructor recorded the definitions on the slide using 'purple ink' which was only visible to everyone on the instructors panel. Fig. 8 shows a screen capture of a DyKnow panel with a sketch of a pressure vessel. The instructor and scanned a sketch of a pressure vessel along with partially-completed notes on the stresses in different axes. Students were encouraged to write the answers next to the partially-completed notes. In the example shown in fig. 8, the instructor used 'purple ink', which is only visible to students in the classroom on the instructor's presentation screen. The advantage of purple ink is that it does not use any of the student's screen real estate, and instead encourages students to do their own note taking.

Fig. 9. Screen capture of a DyKnow panel showing how an in-class problem can be presented. The amount of room to work a problem is not large, and pen resolution is not as good as a real pen and paper, so simple problems are better in this type of application than complex, detailed problems. Fig. 9 shows one of the limitations of DyKnow and Tablets. The problem shown is a relatively simple spherical pressure vessel problem that only requires one equation. In a simple problem, the amount of screen real estate and limited resolution of the tablet pen are not a problem. For more complex in-class problems, other techniques are used to present problems and solutions. In fig. 8, the problem was easily solved by students in half of the Tablet screen, and the limited pen resolution did not present a problem. It is possible to present more complex problems and solutions using DyKnow and Tablet PC technology. One technique that worked in the Mechanics of Materials course was to place scanned solutions to problems (solved by hand) on DyKnow panels, and refer to steps in a solution or derivation during the lecture. The instructor can call upon individual students to circle parts of the solution to verify understanding and to keep everyone following along. A variation of the scanned, complex solution method is to have all lecture content scanned and uploaded onto DyKnow panels, and then to give the presentation on the whiteboard using

traditional methods. As each page of notes gets presented, the instructor can index to the next DyKnow panel while still writing all information on to the whiteboard. In this variation, the students have full access to instructor notes on DyKnow but may still take notes in the traditional manner if this is their individual preference.

Fig. 9. Screen capture of a DyKnow panel showing the results of a web poll. Fig. 9 shows the results of a web poll, showing a method for instructing boundary conditions for deflection by integration methods. In the poll given, only 26% of the students answered correctly, indicating that this particular concept needed additional classroom instruction.

Fig. 10. Screen capture from a DyKnow panel, showing course objectives. The course objectives were frequently referred to during the quarter. Fig. 10 shows a screen capture of the course objectives. Several times during the quarter, the objectives were reviewed. The instructor was able to circle some of the objectives, to emphasize which particular objectives were being covered on a certain day. Challenges The challenges associated with using DyKnow and Tablet PC to instruct Mechanics of Materials are due to the resolution of the screen, and initial reluctance of students to use DyKnow. The resolution of the screen was mitigated by scanning all detail-intensive notes ahead of time, and screen capturing them into the DyKnow file. During lecture, the solution would be written on the whiteboard and/or highlighted in DyKnow line-by-line. The advantages of this method are that students have a complete record of what took place during lecture, and students have the option of taking notes in any format (Tablet or paper). The disadvantages include having to scan notes ahead of time, and student complaints that the lecture is spread between two media. For example, some student comments on the course evaluations indicated that they did not like

having to use both whiteboard and DyKnow. In actuality, the students have the option of using either or both note-taking formats depending on what works best for each individual. The initial reluctance to use DyKnow is based on several issues. One issue is having to download the software on to a student's personal computer to enable viewing DyKnow files after class. Another disadvantage from a student's perspective is that they need to spend time downloading (and possibly printing) each saved DyKnow file from each lecture. Several students raised this issue during the quarter as well as on the course evaluations. Some students mentioned that other instructors will give paper printouts of PowerPoint presentations, and suggested that this could be used for DyKnow-based lectures. A perceived challenge of DyKnow and Tablet PC is that the technology is not suited for calculation-based courses such as Mechanics of Materials. The experience shown by the usage discussed in this paper indicates that the technology worked well considering it was a first-time usage. Further refinements are necessary. Conclusions Preliminary conclusions about DyKnow and Tablet PCs are: 1. The technology is here and will improve with time. The technology should continue to be studied, rather than shunned. Although students at this point in time appear to be neutral or possibly adverse to the new technology, future students will increasingly be relying on Tablets and learning through this type of medium. 2. Using DyKnow and Tablets in the classroom does not mean that the whole course has to be run through the software. A more gentle use of the technology is recommended. DyKnow and Tablet PCs work well when they are transparent to the process. Courses can be taught in such a way as to not require the students to use it. Pre-written and scanned notes on a DyKnow slide can be written whiteboard during class, as they would be anyway. Daily lectures can proceed at a whiteboard writing pace. DyKnow is there in case a student wants to use it exclusively (instead of paper), and it also serves as an archive of all lectures. Students that miss class, or just want to study for exams, find the archived lectures to be useful. Otherwise everyone can decide if they want to use it, and at what level. 3. The best things about DyKnow and Tablet PCs are that everything is archivable and that lectures are easy to put together to include rich content. Capturing graphics for use on DyKnow slides is easy. DyKnow and Tablet PCs, at minimum, can be used the same way others use transparencies. A DyKnow slide is a much higher quality visual than a transparency. 4. DyKnow has at least two simple, easy to use features that help liven a classroom discussion: polling and stoplight. Polling is easy, and a quick way to get everyone back into a discussion. However, polling should not be overused or used as a substitute for instruction. The 'stoplight' feature can be used to find out how well everyone in the classroom is understanding a certain topic. The stoplight feature is good but should be run 'anonymously' for more reliable information.

5. Putting too many handwritten notes on a Tablet PC screen is ineffective for instructors, and frustrating for students. The resolution is not good yet. Acknowledgments The author acknowledges many helpful discussions with colleagues Olson and Stienstra, who co-taught non-DyKnow sections. The author also acknowledges Dr. Julia Williams, Ms. Shannon Sexton and other DyKnow users at Rose-Hulman who have shared their DyKnow and Tablet PC techniques without reservation. Biographical information Patrick Ferro holds B.S., M.S. and Ph.D. degrees in Materials Engineering from Cornell University, Oregon and the Colorado School of Mines respectively. He has materials engineering experience in the investment casting, silicon and alternative energy industries. Patrick Ferro (ferro@rose-hulman.edu) has been a faculty member at Rose-Hulman Institute of Technology since 2005.