This paper discusses the derivation of effective means for undergraduate students to learn basic engineering principles. The assumption is that students must actively experience engineering principles in order to develop an understanding they can apply to problems where these principles are involved. The project therefore focuses on experiential learning. These ideas are applied to the design of a new unitised fluids and particle mechanics subject. The paper presents a curriculum that focuses on application of knowledge, and which is centred around a team-based hands-on assignment series that leads students to designing a small-scale piping system. Assessment of hands-on assignments requires students to reflect on the value of their learning with a self-assessment scheme, which requires students to mark their own submissions and justify their choice of marks. This paper fits within a project that aims to establish the possible benefits of designing a student workshop for students to experience basic engineering principles and challenge their engineering creativity.
Introduction
Engineering practice is largely concerned with applying principles of physics, chemistry and mathematics to creating and operating equipment or processes that meet some set of specifications. Therefore, engineering education should be about learning and applying these principles to solve real problems, as opposed to artificial ones.
Despite the high standard of theoretical education, few are the students who can confidently translate learnt theory to practice. This issue is often a source of consternation for industry, which is increasingly expecting turnkey graduates (Buonopane, 1986). Although the majority of undergraduate engineering courses are justly turning to problem-based teaching to overcome this educational deficiency, the vast majority of problems remain paper-based and are largely concerned with what may be referred to as dry-calculations. Paper-based problem-solving has its limitations, in that it can leave some students with a superficial understanding devoid of solid grounding. This is probably one of the reasons why, even despite the increasing role of paper-based problem-solving sessions, students often remain unable to quote or relate to the order of magnitude of basic engineering quantities. The author believes that this is partly due to the lack of opportunities students have to manipulate these quantities in a physical sense. Practical components are often included in the design of engineering subjects to get round this widely acknowledged deficiency. Unfortunately, these practical components often evolve into "standardised" exercises that are sanitised of their learning value through misplaced, although well-intended "perfecting".
Generally speaking, it is safe to say that engineering undergraduates are rarely given the opportunity to experience engineering principles first-hand during their undergraduate years. This is particularly true in the first years of their engineering degree, which is precisely the time when they are introduced to basic principles of engineering that are so vital for deriving solutions, let alone innovative solutions, to applied problems.
In this paper, the author proposes to adopt a different approach to traditional practicals in order to assist students with bridging the gap between theory and practice. This approach consists in giving students the opportunity to experience basic engineering principles through "hands-on" problems. Such problems could be defined as open-ended exercises with a significant hands-on component. The main characteristics of these problems are described in the section below.
Procedure used to design hands-on problems
The first step used by the author to design hands-on problems was to identify the subject aims in the sense of the Dreyfus model of skill acquisition (Dreyfus and Dreyfus, 1986). This step led to (1) selection of the principles or concepts that would be presented in the subject, and (2) ranking of theses concepts into two main categories:
- competency concepts, and
- beyond-competency concepts
It should be noted that such a step is also the starting point for the design of any criterion-referenced assessment strategy. It was evidently planned to integrate the hands-on problem in the assessment package for the subject. Competency concepts were defined as those that, in the opinion of the teaching team, each student in the class should be able to apply confidently to real problems in order to pass the subject. The primary aim of hands-on problems is to assist students with learning the concepts that define competency in the subject. What the author refers to as "beyond-competency concepts" are the concepts the Dreyfus learning model would associate with expertise in the field of fluid mechanics.
In addition, an appropriate degree of open-endedness was built into the hands-on problems for three reasons:
- Firstly, hands-on problems provides us with a means of formulating problems
with a multitude of possible answers, whereby helping students de-construct
their "right or wrong answer" framework.
- Secondly, such problems can in principle give students a real opportunity
for exercising their creativity. Creativity is a skill that is recognised
by many as lacking amongst engineering graduates, the fault being incumbent
upon curriculum deficiencies of course, not the students!
- Thirdly, the open-endedness of hands-on problems can be exploited to challenge students who wish to go beyond the level of competency in the subject.
Finally, it was understood that the hands-on problems would have to be well integrated within the subject. Indeed, there should be a logical continuity between these problems and the other subject activities, such as lectures or tutorials.
Application to an Engineering Subject at UQ
The design ideas presented above were applied to the design of the newly unitised "Fluid and Particle mechanics" subject at UQ. This subject, which is offered to 2nd year engineering students, condenses two previously distinct subjects in approximately half the original contact time. This dramatic reduction in contact hours, which was initially felt as a major obstacle, was in fact a blessing in disguise. Indeed, it forced the teaching team to examine the subject aims critically and clearly delineate the subject concepts on the competency scale that was needed to design hands-on problems.
It was recognised that the principal aim of the subject was to lead students to acquire the skills necessary for them to be able to solve basic pipe flow problems. Acquisition of such skills implied learning about the following competency concepts: fluid properties, pressure and head, flow measurement, pipe head losses and pump characteristics. It is interesting to contrast these aims with those of traditional university fluid mechanics subjects, which teach students at a more abstract level. As a result of a competency analysis of fluid mechanics teaching at the undergraduate level, it was sensibly decided that a companion subject would be offered as an elective later in the course. This advanced elective will provide students with an opportunity to learn beyond competency concepts in fluid mechanics, which stem from differential fluid flow analysis.
The subject design, which was assessment driven, led to the inclusion of four (4) hands-on exercises, each one building on the previous one(s). An overview (see appendix) of the hands-on exercises was given to the students at the start of the subject. The intended aim of informing students about the overall scope of the hands-on problems they would be expected to solve during semester was to create a sense of purpose and cohesion to the subject. This was reinforced in a companion timetable that gave detailed scheduling of the hands-on exercises along with the accompanying lectures and other subject activities.
The underlying competency concepts of the second task for example, namely "Development and calibration of an in-line flow measurement device" (See appendix) included pressure, flow measurement and head losses. Student teams composed of 4 or 5 students, were given a piping "kit" that comprised a number of pipes of various diameters and connecting elements to complete the task. Essential operating specifications were given for the design of the flow meter in a succinct handout, such as basic operating principle and range of operating flow rates. No suggestion was made about possible design options.
Evaluation of the approach
It is important to stress that this article is being written while the subject in question is still on-going. Hence, the analysis of the effectiveness of the approach that follows is largely subjective and anecdotal at this stage, and is the result of the author's self-evaluation and observation of students' work. Although student feedback has been collected for two hands-on problems so far, the analysis of the feedback is not complete. It is planned to write a companion article that will include a more objective evaluation of the approach on student learning.
To many students, it was apparent that it was the first time they had been faced with such an open-ended problem. The students were assigned a nominal 2-hour laboratory access time per week to work on this particular problem, which was to be completed over a 4-week period. Students were largely unsupervised during these working times, however teaching staffs were available for informal consultation. The author spent a number of hours "walking" amongst student teams at work, as an observer. The nature of the questions students raised, often essential from a comprehension perspective, confirmed the value of hands-on problems to teaching fluid mechanics. The author believes that the approach forces students to question the level of their understanding, because they need a real understanding to complete the task. Such qualitative observations can be interpreted as evidence of the deep-learning value of hands-on problems.
Approaches to solving hands-on problems appeared to vary considerably between student teams. Some would not hesitate to dive into the construction of the flow meter, only to realise later that some preliminary calculations, a step which must occur to link theory and practice, could be of value to their design.
Other students would spend a very long time carrying out dry calculations prior to building their design, in search for the elusive "right answer". Some teams in fact showed great difficulties with coming to terms with the fact that they had to make so many assumptions in order to design a real system, crippled by indecision due to all the possible solutions to the problem. At some stage though, which often coincided with seeing designs built by other teams, they would realise that engineering principles allow them to predict so much, and that they must sooner or later make a decision and assemble a working set-up. This confidence building effect hands-on problems have on students learning is possibly one of the most profound benefit of the approach on student development. It has to do with forcing students to deal with their own accountability, an important quality for practising engineers.
Most students feel comfortable with paper-based problem-based sessions, since "the bridge won't fall" irrespective of the depth of their understanding of the concepts involved in the calculations. Designing a working piece of equipment or process, notwithstanding the complexity of the principles involved, forces them to another level of accountability which traditional problem-based approaches cannot provide.
On average, it was observed that students seemed motivated by the problems. They would often ask to be allowed to come outside their nominal scheduled work time to try some of their ideas in the laboratory. On several occasions, students verbally indicated that they were enjoying the task. Some students however complained about the lack of direction, a reflection of the overwhelming feeling hands-on problems can create. Such a situation necessitated the support of the teaching staff in the form of discussions that reinforced the linkages between the problem and the material presented in the other subject activities, particularly the lectures.
This brings us to an important issue, which is that all staffs involved in the subject must be well aware of the problem being solved by the students. Too often do we witness situations where a lecturer is not fully aware of the details of the practical components included in her/his subject. This often occurs when lectures and practicals have lost touch over the years. Such a situation cannot be permitted for hands-on problems to be effective, because teaching staff are continuously called upon by students to discuss problem related matters.
An additional issue that appeared to compromise the effectiveness of the approach was internal team working problems. The author is of the opinion that these skills should have been formally and effectively taught to the students before the start of such exercises. This latter comment applies to all team-based exercises, not just hands-on problems. Efforts will be applied to alleviate this difficulty in the next edition of the subject.
An aspect of self-assessment (Boud, 1995) was introduced as part of the assessment of the hands-on exercises. Because the initial competency analysis of the subject concluded that assessing reporting skills was not a justifiable subject goal, the focus being on technical concepts, report templates were provided for students to hand-in their results individually. These templates included five sections, namely:
- Team effort and effectiveness (rating of team members' contributions,
comment about student role and contribution to the team)
- Technical approach (justification of principles used for the design)
- Measurements and calculations
- Technical diagrams
- Critical analysis of task completed (opinion about learning value of the hands-on problem and ideas for improving it)
Self-assessment meant that students were required to rate the quality of their work for each of these sections, by assigning themselves a mark and more importantly, by providing a written explanation for their choice of mark. The student self-assessment component, in particular the justification for the choice of mark would be taken into consideration by the marker in the assessment of the student's work.
Self-assessment was therefore used to force students to reflect on the quality of their own work, so as to emphasise their individual accountability. Notwithstanding the fact that students did not receive any training in self-assessment, which may diminish its value (Fazey, 1993), it is premature at this stage to comment on the effect self-assessment had on student learning.
Some comments to do with the logistics of hands-on problems
The design phase of the hands-on exercise was time consuming. In particular, it required envisaging multiple options for solving the problems so as to provide students with a sufficient variety of piping components for them to be able to consider several solutions. This planning stage required a significant amount of up-front work on the part of the teaching staff.
A significant advantage of hands-on problems is that they offer a great degree of flexibility from one year to the next, contrary to traditional practicals, which are often too inflexible to offer much scope for change between successive years. It is for instance very simple to conceive a number of problems along the lines of the one described in appendix, such that problems can really be different from year to year. Furthermore, hands-on exercises provide great flexibility for changing the emphasis of a subject, in response to a shift in subject goals from one year to the next.
Some may question the feasibility of deriving hands-on problems with complex underlying concepts. Daignault et al. (1990) discuss the assembly and use of an Ostwald-type viscometer made from readily available materials. The experimental set-up consists of two glass tubes connected by rubber tubing. The authors state and prove that their simple viscometer is suitable for demonstrating the basic principles of rheological measurements to students. Although Daignault et al. do not go as far as asking the students to actually conceive and build their own viscometer, their paper demonstrates that it would be feasible to get students to do so and actually measure the viscosities of common liquids. Such a hands-on exercise would undoubtedly lead students to a deeper understanding of a complex concept, that of viscosity.
An interesting issue is to do with the comparison between traditional practicals and hands-on problems from a logistical standpoint. Because hands-on problems can only be small scale, the approach used by the author was to include laboratory demonstrations run by expert researchers during semester. These demonstrations aimed to give the students another perspective on various issues relevant to the hands-on problems as well as reinforce the material covered in lectures and tutorial sessions. Overall, because the class was large (130+ students), the amount of contact hours between staff and students that resulted from the combination of hands-on problems and laboratory demonstrations was less than that required to run traditional fluid mechanics practical sessions in previous years. Furthermore, the report templates mentioned earlier, with its strict page limit and limited write-up requirement, also reduced the time required for marking, which also led to more rapid feedback to the students.
Can we improve?
In the field of fluid mechanics, with its widespread practical applications, the use of hands-on problems makes sense. In the author's opinion, the benefit of the approach could be greatly enhanced should a dedicated facility had been available for the students to use for their hands-on assignments. In the future, it is hoped that this experience will lead to the construction of a dedicated student workshop where undergraduate students can really exercise their engineering creativity in the field of fluid mechanics. Such facilities have been constructed elsewhere (Mildren et al. 1998).
As mentioned earlier, close attention should be given to teamwork skills, as lack of skills in this area strongly affects the ability of students to benefit from hands-on problems.
Conclusions
The predicament on which this paper is based is that students should be given opportunities to actively experience engineering principles in order to develop an understanding they can apply to problems where these principles are involved. A possible solution was proposed in the form of hands-on problems.
It was recognised that there is a common denominator between the derivation of hands-on problems and that of criterion-referenced assessment strategies. The common denominator lies in the clear identification of the subject goals. Hence, the design of hands-on problems seems to flow on logically from the subject assessment scheme. The implication is that the introduction of hands-on problems in a subject must be justified from an assessment viewpoint.
Although only very qualitative evaluation was available at this stage, the effect of the hands-on problems on student learning seemed positive. Hands-on problems, because they lead to a palpable finished product, appeared to be a good motivator for the majority of students. Being able to construct a working device or a process has potential to help building student self-confidence, accountability and skills in problem-solving. Because of the requirement that students deliver a real working "product", hands-on problems were felt as promoting deep-learning of fluid mechanics concept. It is planned to publish a more conclusive evaluation of the approach by reviewing the various forms of feedback returned by the students.
Some difficulties were experienced in the area of team management, and future editions of the subject will need to consider efficient means of giving students adequate team-working skills.
Acknowledgments
The author wishes to thank his team teaching colleagues, namely A/Prof. Jim Litster and Dr Tony Howes from the Department of Chemical Engineering at UQ for their assistance during the design of the "Fluid and Particle Mechanics" subject. The significant support provided by Mr Sante DiPasquale from the Department of Mining, Minerals and Materials Engineering Department at UQ with organising the hands-on problems is also greatly acknowledged.
References
Boud, D. (1995). Enhancing Learning Through Self-Assessment. (1st ed.). London: Kogan Page.
Buonopane, R.A., 1986. Engineering Education for the 21st Century, Chemical Engineering Journal, 20/2, 166-167.
Daignault, L.G., Jackman, D.C. and Rillema, D.P., 1990. A Simple and Inexpensive Student Viscometer, Journal of Chemical Education, 67/1, 81-82.
Dreyfus, H.L. and Dreyfus, S.E. (1986). Mind over Machine, New York: Free Press.
Fazey, D.M.A. (1993). Self-Assessment as a Generic Skill for Enterprising Students: The Learning Process, Assessment and Evaluation in Higher Education; 18/3, 235-50.
Mildren, S., Whelan, K. and Chappell-Lawrence, A. (1998). Introducing Teamwork as a Teaching and Learning Paradigm in Engineering Education, in Proceedings of the 1998 Australasian Association for Engineering Education, 1, 27-31.
Appendix - Overview of the hands-on assignment series handed out at the start of the subject
The Chemical Engineering Department has a problem. The fish in the fish tank on level 3 keep dying!! We believe the problem is poor water quality.
Our bright idea is to recirculate the water through en external fluidised bed activated carbon filter. The four (4) assignments relate to designing, building and testing the filtration system. We want to accurately measure and control the flow of water through the filter. Therefore, the system consists broadly of three parts: pump, fluidised bed filter and flow measurement device. These will be linked mainly by 13 mm ID tubing. One potential configuration of the system is given below.
The four (4) assignment tasks deal with:
- Characterisation of the activated carbon particles.
- Development and calibration of an in-line flow measurement device.
- Characterisation of the pump performance.
- Fluidised bed characterisation, final assembly and demonstration of the filtration circuit.
You will be provided with a detailed description of individual tasks during semester, and the necessary equipment will be provided. The submission schedule is given in the 1E203/E5255 subject outline. The team roster for lab scheduling is available on the web, as well as the assignment submission form.