Fulfillment of Requirements

This section will discuss the fulfillment of the requirements defined in section 4.2.

Non-Functional Requirements

ID Type Discussion

NFR-1 Reusability Though the application, it was generally built a good foun-dation for reusability. Prefabs were developed for cartridges and doors. Also, the room structures objects for level design, and other assets can be reused to create more content. The calculator can also be easily reused and modified by swap-ping the activation function. The notation tasks were some-what reusable but needs further work to increase reusability.

NFR-2 Usability Based on the feedback, it seemed like users were generally picked up how to use the application quickly and were satis-fied with the tutorial’s length and contents. The users men-tioned some bugs and design issues in the written feedback that should be fixed. Also, some users requested that al-ternatives for locomotion should be implemented for more experienced users. The users were generally highly experi-enced with VR, so a full SUS test should be conducted on a group that better reflects the whole target audience. See-ing that multiple users experienced discomfort, further work should be put into optimizing the application.

NFR-3 Modifiability A high focus was put into keeping the application modular and documented, so making changes to the current code base should not be too difficult. Unity’s event system was used to keep the different objects of the application modular so that references can be set up in the Unity editor, instead of ”hard-coding” this in the scripts. Also, by using VRTK as an SDK for interactions, it should be possible to add support for other VR headsets than Oculus without too much effort. However, to update SDKs like VRTK, more extensive work would be needed to update references in the Unity editor.

NFR-4 Extensibility Extensibility was facilitated in the quiz system for adding new cartridges. The game menu was developed with room for adding new AI topics. The assets can easily be reused to create more content. Especially the choice of using Unity Snaps [59] for building room layouts, makes it easy for de-velopers to extend the application’s contents with new rooms easily.

NFR-5 Performance Through the first parts of the application, the performance is generally good and near to 72Hz. However, multiple users experienced discomfort in the last parts of the application because of performance issues. The issues were caused by a high amount of grabbable objects with TextMeshPro. This shows one of the weaknesses of using a standalone VR head-set and the importance of focusing on optimization.

Table 6.1:Fulfillment of non-functional requirements

Tutorial

All the functional requirements for the tutorial (see Table 4.2) were implemented as planned.

Based on the observations of participants from the student housing, it seemed like the tu-torial covered the necessary interactions well. Also, as discussed under usability in the non-functional requirements, it seemed like the users thought the application was easy to use and satisfied with the tutorial’s length.

Considering T-FR5 about learning how to interact with physical UIs, the users had prob-lems understanding how to point and use the pinpad. From the observations, it seemed like the touch sensor on the index finger trigger caused this problem. Since the users rested their fingers on the trigger, the virtual hand’s finger bent and could not be used for interaction. A future solution to this would be to either disable the touch sensor on the index finger trigger or to automatically make the hand point when being near a physical UI.

6.2 Phase 2 Deep Learning Introduction

This section discusses whether the functional requirements for the deep learning introduc-tion (see Table 4.3) were fulfilled or not.

ID Fulfilled Discussion

FR1 Yes The topics were separated in rooms like you see in Fig-ure 4.9. Since backpropagation is a big topic, it was split into multiple rooms.

FR2 Kind of The application used a too high amount of text for learning materials, but also used some 3D-visualizations. For future work, the text should be replaced with more of the other learning material types.

FR3 Mostly Users understood the order of learning materials for neurons, cost functions and backpropagation, so they could apply it in tasks. Some users were confused by the order of learning materials for gradient descent. The learning materials for backpropagation seemed to be placed in an intuitive order, but were lacked content.

FR4 Yes The quiz system was implemented and described in section 4.3.9. The quiz system had a few design issues, but users were generally satisfied with the way it worked.

FR5 Yes Users seemed to understand the perceptron task.

FR6 Yes Users seemed to understand the sigmoid neuron task.

FR7 Yes Multiple users stated that this visualization was the applica-tion’s best utilization of the VR technology and saw more potential in adding possibilities of manipulating the visual-ization.

FR8 Yes This task was implemented to let users place neurons. One user mentioned that this was a better approach for learning notation, compared to lecture slides.

FR9 No An animation for backpropagation was not implemented due to a lack of time.

FR10 Yes The task was implemented, but users found it somewhat con-fusing to understand how to do the task using the available learning materials.

FR11 Yes The questionnaire could be opened in the Oculus Quest browser.

FR12 Yes Using the quiz cartridges to open the final door was some-thing that some users liked. One user felt that it was unnec-essary.

FR13 No Implementing an open-ended task to put everything together was thought to be too time consuming for a master thesis project and should be prioritized for future work.

Table 6.2:Fulfillment of deep learning introduction functional requirements