1. Introduction
Accurately understanding a building design is critical for making effective decisions. The architecture, engineering, and construction (AEC) domains require teams of professionals to collaborate to effectively design and build infrastructure. This collaboration has traditionally involved the communication of complex three-dimensional (3D) concepts using two-dimensional (2D) plans (i.e., “blueprints”). This 2D mode of communication has been used for hundreds of years and continues to be used as the format for contractual deliverables to enable stakeholder communication [
1,
2,
3]. To be prepared for this kind of interaction, it is important for students to understand how to define construction processes based on their design comprehension.
Recently, educational researchers have focused on how 3D modes of communication can lead to effective design comprehension by construction students. Some have explored the use of emerging visualization tools such as augmented reality (AR) as resources for performing various construction-related tasks [
4]. Augmented reality is “any case in which an otherwise real environment is “augmented” by means of virtual (computer graphic) objects” [
5]. Some have even compared student performance between 2D and AR conditions, where users relied on one modality or the other as a design resource for performing construction-related tasks [
6]. One group compared 2D and AR as modalities for presenting a design, and with a written questionnaire, found much higher design comprehension when receiving the design in an AR modality [
7]. Others have explored the advantages of enhancing 2D documentation with AR content for field-based tasks with industry practitioners [
8]. These studies illustrate some of the ways that AR may offer benefits compared with 2D documentation to support design comprehension, but they focus on the use of AR as an input or resource to support this understanding. In this paper, an activity ‘input’ is any resource provided to inform a student’s understanding of a design concept, and an ‘output’ is the resultant product that students deliver upon completion of the activity. In this case, the output constitutes the student’s defined means of creating and documenting their actual construction sequence.
This study focuses on student behaviors and perceptions when given 2D plans as a design input or resource used to define a sequence for each piece of wood required to construct a section of a wood-framed wall. In this study, each intervention explores a different mode of visualization output, with both still using the 2D input, that students may use to see the results of their process: either a 2D worksheet (Intervention 1); or an AR-based model (Intervention 2). While 2D materials are common classroom educational tools, AR is an emerging tool that is much less commonly used and has not been the subject of extensive study in a classroom context. This work identifies ways in which students’ construction sequencing processes and perceived experiences compare when they view their defined processes in these differing formats.
Research shows that design comprehension can be developed through experience. A study by Hölscher & Dalton [
9] revealed that people with actual experience in architecture were much better able to understand design complexity in 2D documentation (as opposed to video presentation). Another study concluded that design comprehension a skill that can be developed through experience, not just ability [
10]. In construction research, Dadi et al. [
11] found that workers in construction fields who frequently leveraged drawings in their work were able to use drawings to perform assembly tasks more efficiently and confidently than their less experienced counterparts. In addition to technical skills development, hands-on, authentically situated experience in the construction fields has been known to provide motivation to students as well as to helping develop independent problem-solving skills [
12]. Given these clear advantages of authentically situated learning experiences, providing students with access to these activities would develop the skills and attributes that would best prepare them for design comprehension and success in industry. From these works, it can be concluded that students who have authentic learning experiences, or experience in building certain types of construction, can generally do this effectively. While most educators understand these advantages, the realities of higher education classrooms are such that most students do not have access to authentic, hands-on learning activities in the classroom. This limitation is likely due to the high cost and resource requirements needed to bring these types of activities to a class or lab [
13]. Given the known advantages of authentic learning but the extremely limited access, this work seeks to understand the ways in which students perform element sequencing tasks when using AR to simulate the physical interactions of authentic learning with the low cost of traditional design communication, comparing with traditional 2D outputs as a baseline for what may be expected in a traditional classroom.
This work provides context to the broader learning community of educators who are considering leveraging various modalities to teach relevant construction skills. For the outputs for the student work, the 2D worksheet was chosen to replicate a typical classroom situation, and AR was chosen to explore an emerging technological tool with the potential to bring authentic, active learning into the classroom, as it mimics the kind of environment and physical movements that may happen on an actual jobsite. Presenting the task virtually through AR and not physically with real materials was chosen to explore the viability of AR as a low-cost, reusable alternative to using and discarding real construction materials. The results presented here provide insights to allow more informed decision making when considering AR and 2D methods for teaching construction sequencing tasks based on 2D documentation.
4. Results
4.1. Descriptive Statistics
The 2D activity involved 38 undergraduate student participants with varying levels of experience in both school and industry. The dataset included 1 freshman, 5 sophomores, 15 juniors, and 17 seniors. Self-reported racial and ethnic backgrounds included the following: Black or African American = one, Hispanic or Latino = 11, White = 23, Other = two, Prefer Not to Answer = one. Finally, 31 participants self-identified as male and seven as female. Regarding wood framing abilities, the average self-rated scores for participants on 1–5 Likert scales were 3.8 for ‘understand design and construction documents’, 3.9 for ‘find information such as sizes and dimensions on design and construction documents’, 3.0 for ‘decide on means and methods for installing a structure based on the documents’, 3.3 for ‘define a sequence for installing wood framing components’, and 3.2 for ‘install wood framing components correctly’.
For the AR activity, a total of 15 undergraduate student participants successfully participated in the protocol, including two sophomores, 10 juniors, and three seniors. The racial and ethnic responses to the survey included American Indian or Alaska Native = one, Asian = two, Black or African American = two, Hispanic or Latino = three, White = six, Prefer Not to Answer = one. The self-identified genders of the students included 12 males and threes female. Regarding wood framing abilities, the average self-rated scores for participants on 1–5 Likert scales were 3.7 for ‘understand design and construction documents’, 3.9 for ‘find information such as sizes and dimensions on design and construction documents’, 3.0 for ‘decide on means and methods for installing a structure based on the documents’, 3.2 for ‘define a sequence for installing wood framing components’, and 3.1 for ‘install wood framing components correctly’. Notably, these averages were very similar to the average abilities reported by the group involved in Intervention 1 (2D Output), with no statistical difference in any of the categories in independent sample t-tests, demonstrating comparability between the two samples regarding self-reported abilities on wood-framing-related tasks.
4.2. Emergent Themes
The participant think-aloud statements and reflections are combined with researcher observations from the videos to identify components of the activity that may affect the potential for classroom implementation and learning and are presented thematically. From this analysis, the major themes of interest are presented. For the 2D Output, the two major emergent themes that are discussed in this paper include Visualization Difficulties and Extemporaneous Approach (see
Table 1). For the AR Output, the two major thematic categories that emerged include Visualization Enablement and Self-Regulated Approach (
Table 1).
Supporting evidence and clarification regarding the themes and codes presented in
Table 1 are shown subsequently, organized by theme.
4.2.1. Theme: Visualization Difficulties (2D Output)
In the 2D worksheet format, a common theme that emerged was visualization difficulties, where students struggled to maintain an accurate mental model of the process they were planning. One prominent indicator of visualization difficulties was mistakes made and left unfixed. A mistake in this context refers to when a student chose a piece from the schedule of materials and indicated their intention to place it in a specifically labeled location where the item length did not match the dimension indicated by the drawings. It was observed that over half of the students (53%) made at least one mistake when determining their sequence.
Examples of commonly occurring mistakes include when students chose the wrong length for a vertical stud, when they selected the wrong dimension for the top plate, and when they selected the wrong type of piece for the double header, or did not realize there was a double header (see the
Appendix A for the drawings). For some of these mistake types (the top plate and the double header), the students would have to refer to the plan views in addition to the elevation view to obtain a complete understanding of the elements. The dimension of the top plate is indicated on all the plan views, but not on the elevation view. The size of stud for the double headers is 2″ × 6″, where all other studs are 2″ × 4″. This designation and the back-to-back placement of the double headers are only shown on the “Floor Plan-Header” view of the wall design. The visual representation of the double headers is partially occluded in the worksheet isometric view and fully occluded on the first sheet of drawings. While all drawing sheets were provided to students as a set, it appears that there was some difficulty in utilizing all drawings together, evidenced by the abundance of errors on the worksheet. Difficulty accessing information that can only be found by accessing multiple drawing sheets has been reported as a potential issue even for industry practitioners [
8], and this issue seems to be fully present in student learners when using a 2D visualization format. While some students eventually corrected their mistakes during the process or in their final review, they still noted visualization difficulties in the process. Furthermore, more than half of the students who made mistakes (29% overall) finished the exercise with at least one error remaining unfixed and unrecognized upon completion.
In the activity reflection, where students discussed how their process might differ if they performed the AR task, visualization difficulties were a common theme. In fact, 29% of students mentioned visualization challenges in their reflections. Many suggested that keeping track of pieces and the installation order was difficult. For example, one student said “on paper it was hard to remember what I had put in place and what was still in the lay down” providing evidence that keeping track of an updated mental model of the defined construction sequence was a challenge for students. Many students also recognized their own propensity for making mistakes in the 2D worksheet format, suggesting that in AR, “I would be able to see the errors I was making instead of guessing if I was on the right path” and that “I would physically be able to install each piece and see where it goes. I would also be able to visualize where I made a mistake and why I made that mistake. This would be able to provide immediate feedback”. One student summarized their perceptions on the struggles of the 2D worksheet and the potential for AR using their personal industry experience as a factor, stating “With an augmented reality experience the activity would be much less conceptual. Without the experience I have in architecture and construction it would have been difficult to correctly identify which pieces go where in the activity as well as what order to install them in. The augmented reality allows you to have a hands-on experience and visualize the construction process which is incredibly useful when learning about construction”. These comments and ideas principally served to illuminate the difficulties students had in forming and updating mental models, but also provide ideas of what themes and evidence may emerge in the AR intervention.
4.2.2. Theme: Extemporaneous Approach (2D Output)
Most students who completed this exercise did so quickly, and typically without second-guessing or making critical checks. Notably, all students completed the activity well within the allotted timeframe. The average time students spent actively completing the activity was 9 min 8 s, with a range from 2 min 47 s to 21 min 40 s. Considering the average time and the fact that all students placed all pieces, the average time spent per piece was 32 s. The high speed of completion provided extra time for students to reflect, identify errors, or fix mistakes, but despite this time, no students revised their final sequence when provided the opportunity. This may indicate either low ownership in the task, high confidence in the correctness of their selections, or the inability to identify their mistakes. Based on post-activity survey data, this decision was likely tied to high confidence, with most students perceiving their work as highly successful, regardless of errors (see
Section 4.3). For example, one student—who still had mistakes in their process—when given the opportunity to review and revise their work, either did not notice or decided not to change the errors and stated “I think I’m good”. In addition to the speed and lack of revision, the researchers noted that most students did not reach out during the process to ask questions, choosing to complete the task independently, even though the facilitator was available at all times. Even among industry practitioners, failure to make critical checks and to pay attention to details [
44] has been reported as a challenge with traditional documentation and 2D formats, and these results provide evidence that a 2D output does not remedy these challenges. Based on Thorndike’s ‘trial and error’ theory of learning, learners are motivated to continue performing actions that lead to success and avoid actions that lead to failure [
45], suggesting, as many researchers have since, that there is value in encountering and learning from failures [
46]. This is only possible when learners understand when they are succeeding or failing, and this 2D worksheet approach did not provide evidence to suggest the self-awareness that leads to valuable learning.
4.2.3. Theme: Visualization Enablement (AR Output)
From the observational data, it was noted that the AR process seemed to facilitate student visualization in order for them to recognize and fix their mistakes. For example, one participant placed a stud on the wrong side of one they had already placed. When the participant reviewed the piece compared to the drawings, the individual immediately recognized and fixed the issue, stating “I accidentally installed the wrong piece… so I had to uninstall and move it. I should have measured first, but I didn’t”. This comment illustrates a lesson learned by this student, recognizing an error in their process that could potentially inform future work. Other students made similar length errors and corrected them, either by gazing at pieces they had already placed that showed a mismatch in length or by comparing their built model with the paper plans (
Figure 6). In addition to recognizing mistakes made during the process, some also recognized mistakes at the end of their building time while evaluating everything they had built. For example, one participant, when asked if they were satisfied, said that they noticed a stud they had placed was not the correct length. The vast majority of students in Intervention 2 (AR Output) recognized their mistakes at some point in the process, with only one student (7%) leaving unrecognized length errors. Two students (13%) left the exercise with one or two pieces rotated incorrectly, which should be noted but cannot be compared to the mistakes made in the worksheet (Intervention 1), since orientation was unchangeable in the 2D format.
In addition to inferential evidence of visualization enabling mistake recognition, students also made comments regarding how the activity explicitly enabled learning through visualization. One student suggested that this activity may have direct real-life applicability, stating “I learned what it looks like to frame a wall…I learned that the process is a lot easier to understand with all of the moving pieces in front of me. Seeing the moving parts with the plans all together made the whole thing make more sense. I can actually picture in my head what those plans would make in real life, and have a better picture of how I would go about developing those plans”. Others made comments suggesting the potential for this modality to help teach lessons with an impact outside the classroom, such as the student who remarked that they “learned to expect challenges” and another who said that their confidence “really did improve” through the process. These findings align with John Dewey’s ‘learn by doing’ theory, which states “we learn only because after the act is performed we note results which we had not noted before” [
47], meaning that when students see and understand their performance, how they achieved those results is solidified in their learning.
4.2.4. Theme: Self-Regulated Approach (AR Output)
The students took a much slower, more methodical, approach to completing the activity in an AR format, likely facilitated by the nature of the interface. In this activity, most of the students did not finish placing all pieces of the wall. Some got close, with one student placing all but the top plate and the plywood backing, while a few spent their time organizing and moving the pieces, but never actually installed any. Notably, the time needed for the setup and registration process varied between students, which determined the amount of time available for active material placement. To objectively understand the rate at which students actively built, the average amount of time spent placing each piece during active building was calculated, resulting in an average of 3 min 26 s taken per piece placed. This average is notably higher than the 32 s per piece from Intervention 1 (2D Output). It is important to note that while both interventions similarly required the students to verify dimensions of existing pieces and to assign a construction order to these pieces, the mechanism for doing so is different between the two. Verbalizing and/or writing a series of numbers is different from physically having to move each one into place. Therefore, the comparison of time per piece is not intended as a measure of which task is superior or inferior, but rather to provide a descriptive understanding of the difference between the two experiences.
In addition to the speed of the activity, it was noted that many students exhibited a pattern of referencing their resources. For example, many took the time to check the drawings multiple times throughout their process. Many also measured each piece before placing it, with some even taking the time to verify the measurements of pieces after installation. Even students who did not get close to finishing had the potential to study and utilize the 2D documentation, with some mentioning learning gains like a student who stated that the activity “helped me understand a lot about building plans that wasn’t clear before. I think I learned more about reading drawings with this experiment [than] even the physical building process”. They mentioned how physically moving the pieces into place while looking at the drawings helped them understand the drawings better, even though they only had time to place a few pieces.
In addition to leveraging physical resources, many students took the opportunity to ask questions of the facilitator, some of which related to the process of framing a wall, with students sometimes asking the facilitator if their work was correct thus far or asking for help reading dimensions on the drawings. While the researcher did not intervene to answer specific questions that would positively or negatively impact the students’ processes during the activity, their interest in asking these types of questions suggest engagement with the task.
4.3. Post-Activity Survey Results
The thematic analysis illustrated differences in students’ abilities to visualize and detect mistakes as well as distinct approaches to each task. In addition to the thematic analysis, the post-activity survey answers to the cognitive load (based on NASA TLX questions and scaling detailed in the methods section) and performance-related questions give further insight into these differences, including mental demand, frustration, and perceived success.
Figure 7 presents these results for the two interventions graphically, side-by-side.
For Intervention 1 (2D Output) students rated their mental demand at 2.8 on average (0–7 scale), and their frustration at an average of 1.7 (0–7 scale), which are both well below the midpoint of the scale. These results suggest that students perceived the task to be easy and not frustrating to complete, despite mixed actual success. For the AR activity, mental demand was rated at an average of 3.7—just above the midpoint—and frustration at an average of 3.2—just below the midpoint. In both measures, the ratings were higher for AR, suggesting that this activity requires more effort and engagement from students in terms of thinking and overcoming frustrating challenges. Some of the frustration could be due to using and learning a new technology, while some might be attributed to the challenges of the sequencing task itself, and this study does not claim to control for these differences, only noting that the overall AR experience presented higher frustration to students than the 2D worksheet counterpart. For both measures, the differences between the two interventions were significant (p < 0.05 for mental demand, p < 0.01 for frustration) using an independent samples t-test. All variables met the assumption of normality needed to run this statistical analysis (skew < 1 for all variables involved).
Regarding students’ perceived success on the activities, the average rating for the worksheet activity was 5.7 on a 0–7 scale. Interestingly, this score was very similar for students who finished the activity with an unresolved mistake (5.6) and for those who finished the activity with no apparent mistakes (5.7), which offers further evidence to indicate that this method may not be ideal for students to engage in trial and error learning, since recognizing mistakes is critical to that process. On the other hand, students in the AR activity rated their success at an average of 2.7 on a 0–7 scale, indicating much lower satisfaction with their performance. It is hypothesized that both an awareness of mistakes and not finishing the activity may both have contributed to the low success rating. The difference in perceived success between the two interventions is statistically significant (p < 0.001) using an independent samples t-test.
5. Discussion
The results of the thematic analysis benefit from contextualization in the learning theory literature. In particular, the behaviors observed during the AR activity point to the potential for learning based on both Thorndike’s ‘trial and error’ theory of learning and Dewey’s ‘learn by doing’ theory. Although considered opposing theorists on some aspects of educational reform [
48], elements of both Thorndike and Dewey’s learning theories persist in some forms today and motivate work in experiential learning. For either approach, the potential to affect student learning is predicated on students’ abilities to identify success and errors by understanding output, which leads to a refinement of their behavioral inputs. In other words, it is important for students to have an opportunity to act for themselves, have successes or make mistakes, and recognize those successes or mistakes. The results from this study provided evidence that these critical checks are not easily facilitated through the 2D input-2D output experience, but are readily facilitated by the 2D input-AR output student experience.
Regarding the survey results, perceived success approximates confidence in a task, and confidence in graduating students is an asset, but perhaps just as important is knowing where knowledge falls short. Often, educators only look at success scaffolding, but failure scaffolding—intentionally exposing students to failure in the learning process—is an emerging research area that may be just as critical to truly internalizing lessons and using that knowledge in meaningful ways in the future [
49]. Using an AR output to help students conceptualize construction sequencing processes from 2D plans may support this process. These activities utilized minimal instructor involvement after initial instruction, a situation often used by design to promote independent learning [
50,
51]. When working independently, students encounter both successes and errors and ideally learn from both. As foundational educational theorist Dewey stated, “by doing” an activity, the student “becomes familiar with its methods” and “acquires needed skill” [
47]. The AR activity emerged as the learning environment that facilitated the performance awareness that allowed students to demonstrate high potential for learning by doing. The survey results align with the approaches that were observed in the thematic analysis, with students approaching the 2D worksheet with speed and confidence, which aligns with the low mental demand, low frustration, and high perceived success of the survey. On the other hand, the higher mental demand and frustration and lower perceived success during the AR activity aligns with the more careful, deliberate, and time-consuming approach that was demonstrated in that activity.
To contextualize these findings within the broader body of emerging technology in education literature, it is helpful to look to other fields. For example, the medical field has been a pioneer in the use of emerging visualization tools for educational training. In one study, students used virtual reality (VR) for practicing medical procedures and reported that they felt safe making mistakes and learning through trial and error [
52]. Although this study used a slightly different medium (VR instead of AR), there was still an opportunity for students to independently utilize an interactive visualization tool as a learning output. This nursing study supports the claims made in this paper that it is beneficial for students to be able to make and correct their own mistakes in a low-risk environment. Another study in the astronomy field also used VR as an interactive classroom tool to teach about moon phases, and students reported that being able to “manipulate the environment” led to better ability to visualize the environment and ability to learn information. However, the study also compared alternative approaches to the learning task, including a non-digital activity and a desktop activity, and concluded that students reported those environments to be easier, faster, or less overwhelming [
53]. These results support the findings of this study that immersive visualization environments may not be the easiest or quickest method of teaching, but seem to have promising potential for meaningful learning gains.
Within construction education specifically, while no exactly parallel study exists in this domain, there are some studies that can offer insight and context to the findings in this paper. A study by [
18] explored student performance in a wood framing assembly task, although this task was presented physically to the students using real wood components, and what varied was their input, which consisted of either paper drawings, full-scale overlaid AR, or scaled-down AR. While this is a study of educational inputs rather than outputs, the findings offer interesting insight. They found that students who used paper resources performed the activity more quickly than those who used the scaled-down AR visualization. However, they found no difference between the paper resources and the full-scale overlay of the AR model. These findings differ from those found in this paper, indicating that there may be significant differences between using AR as an input vs. an output in construction assembly tasks. They also considered student errors, and found a wide variety in the type and frequency of errors using the three methods, but formed no conclusive determination regarding which method better supports mistake avoidance. Many students in this study mentioned that the full-scale AR assisted in selecting the correct pieces, but also mentioned that having 3D graphics overlay physical materials was distracting [
18]. The work presented in this study differs from the Bloomquist study in that there was no overlay of dimensional pieces on physical pieces since the AR activity was the learning output, so although students faced challenges, distractions from the overlay of physical on virtual materials was not one of them.
In another study, students used both 2D and AR as outputs for a learning activity in an architectural design exercise focused on sustainability [
40]. While not a construction assembly task, this work still allowed students to interactively create within these two media, and the researchers found that students felt they had insufficient time to complete the task, but they more frequently held this complaint when performing the task in 2D rather than AR. These findings differ from what was observed in these activities, suggesting that the discipline of the activity, or at least the requirements for student output, will have a large impact on task performance. To clarify, the architectural design study required students to create an open-ended design output, and the study from this paper required students to sequence a set of already existing pieces, so it is understandable that there would be significant differences in the performance of students. In addition to time considerations, while this activity was an open-ended design, and thus did not have an opportunity for students to make what would be considered errors or mistakes, the results did show that students were able to objectively improve their design as they iterated and created new versions within the simulated experience. These findings support the claim that AR can facilitate self-remediation where students independently alter their work to make it better.
Finally, in addition to comparisons with research on emerging visualization tools, it is helpful to draw comparisons to learning outcomes from hands-on construction building activities. For example, in a report regarding student experiences in a national design and build challenge, researchers reported that students showed technical skill development as well as an increased ability to take initiative [
12]. These learning gains align with those reported in this study, where students were able to build more effectively through mistake recognition and to independently improve their performance when performing a simulated hands-on activity in AR. In fact, autonomous decision making has been reported as a key outcome of hands-on project-based learning activities in the construction domain [
54], which is supported by the findings in this paper. Overall, the student performance on the AR activity presented in this work shows promising potential to replicate some of the learning gains that occur in physical hands-on activities.
6. Conclusions
From analysis of each of the two interventions explored, the emergent themes illustrated aspects of student performance that differed using each visualization mode as an output for documenting their work. The students who documented their construction sequences using the 2D worksheet completed the activity very quickly, but did not generally pay attention to dimensional details or make critical checks for errors. On the other hand, the students who documented their sequences using AR struggled much more while completing the activity, but demonstrated more propensity for critical checks, mistake recognition, and self-reflection during their process. Therefore, even though AR was slower and deemed to be more challenging by the students, the results suggest that AR has high potential to replicate some of the behaviors that make hands-on learning beneficial to students.
While the findings of this research may be logical, based on the differences in the experiences provided to students, the approach taken by the authors to use AR as an output for student thought remains uncommon. Instead, most prior works in this domain focus on the use of AR as an input to support students’ comprehension of a design concept. The learning format chosen for AR also influenced the decision to use head-mounted (hands-free), full-scale, and fully interactive AR, characteristics which set this work apart from previous work in this domain. When compared to studies in other domains, this work supports key findings that AR has promising potential as a high-impact teaching tool, especially in providing hands-on experiences to students, but can be challenging or time-consuming. The approach used in this work illustrates ways in which documenting a construction sequence in an AR output can help students to recognize and fix their own mistakes in ways that may not be realistic to expect through 2D outputs. This may be an especially relevant skillset to develop through an AR, or otherwise virtual, mode of communication as long as comprehension of 2D documentation continues to be expected of students when they enter the construction industry, and also while the high cost of physical materials would prohibit most students from being able to physically construct a wall like the one incorporated in this research. As a result, the contribution of this work is in presenting findings that illustrate the opportunities, and potential challenges, related to using AR as an output to challenge students to produce valid construction sequences based on common 2D modes of design communication.