Hot Metal Post-Mortem

I. Introduction and overview of the project

Project Description

Project Hot Metal is an educational project aiming to teach engineering students how to operate a Metal Additive Manufacturing (AM) machine.

Project Goal

With dual-platform support of PC and VR, the goal of the project is to simulate the operation of a metal AM machine and provide instructional support for engineering students. Students will not only have detailed instructions and assessments on the PC platform but also have a practical experience operating the machine in the virtual world. Project Hot Metal will also integrate the prototype with a machine-based tutor created with CTAT (the Cognitive Tutor Authoring Tools), developed by the Human-Computer Interaction Institute (HCII) at Carnegie Mellon University.

Project Deliverable

Our final deliverable includes two parts:

  1. The first part is a functional prototype, including both PC and VR tutorial. The PC tutorial includes 4 steps of unity interactions and their implementations on CTAT. The VR tutorial includes the whole experience operation of the machine.
  2. The second part is the documentation, including tech documentation, hardware installation, design documentation, and results from playtest sessions.


Sandra DeVincent Wolf – Executive Director, NextManufacturing Center

Bruce McLaren – Associate Research Professor, Human-Computer Interaction Institute

Todd Baer – Additive Manufacturing Technician, NextManufacturing Center

Nick Jones – Ph.D. student, Mechanical Engineering

Faculty Advisors

John Dessler – Special Faculty

Scott Stevens – Teaching Professor

Team Members

Tai Ching Cheung – Artist          

Jiming Li – Lead Programmer    

Akash Phadtare – Programmer

Danke Luo – Programmer           

Chenchen Tan – Producer      

Mengqi Wu – Designer          

II.  What went well

Our project delivered a solid and complete tutorial at the end of the semester. Both the team and the clients were proud of what we have achieved. The clients invited the team to present the project at Manufacturing Future Initiative Forum as one of the key projects sponsored by the Manufacturing Future Initiative. There are several key components lead the team to succeed:

  1. Good team communication and good team dynamics really help us work better as a team. Even though there were some misunderstandings and miscommunications throughout the whole semester, we talked it openly and got to know each other better. Furthermore, when the team bonds better, it makes the work easier to be delivered on time with good quality.
  2. A good relationship with clients improves the efficiency of the project development. We maintained good communication with our client throughout the semester. We kept updated our progress with our client so we could get immediate feedback from them. Efficient communication really saved us a lot of time and work in development.

Overall, our project went quite smoothly and well throughout the whole semester. We narrowed down our scope and came up with the best solution, combing both PC and VR tutorial, to fulfill the clients’ requests. We finished what we promised at the beginning with high quality and we had a good time working with each other.

III. What could have been better (or what went wrong)

There would be two things we think that we could do better:

1. Ask for one more artist. In this project, the machine in the lab is very complicated and there are many tools needed in the whole experience. At the same time, our client requires a very realistic art style. However, we only have one artist, even we have a good one, it is still not enough to get everything we need to be done in one semester. So, we need to buy assets and make them fit in our environment as possible.

2. Talk about the scope with our client earlier. If we could figure out the scope better at the very beginning of this semester, we could tell the client how big the original scope(2VR + PC) was. We could tell them how much we could deliver in one semester and let them choose what they prefer earlier. If so, we might cut down some parts of VR and spend a little more time on PC.

IV.    Lessons learned and conclusion

We have learned a lot from this project. We realize that traditional training is quite different from training in virtual reality. We could not simply use the same content in VR. We need to change the content-heavy learning material into interaction-biased training, but also keep those contents in our PC version. Because our target audience is graduate engineering students, playtest sessions by these specific demographics really helps us a lot in the development of iterations.

We felt lucky that we had each other in the same team. Among six teammates, half of the team are going to graduate soon, we wish everyone all the best with a bright future.

Week 15 Dev Blog

It was the last week before the final presentation. Because our project will be continuously developed by another team in the summer, in week 15, our project focused on documenting everything and got the project ready to be delivered to our clients.

The clients were very excited with what we have achieved this semester and invited us to showcase our project at manufacturing futures initiative forum as one of the key project sponsored by Manufacturing Future Initiatives. We were very excited to present our project at such a formal event before the end of the semester.

MFI Forum poster
MFI Group Project

We are looking forward for our final presentation!

Week 14 Dev Blog

We cannot believe that it is already week 14. Next week, April 29th, our project is going to participate in the inaugural Manufacturing Futures Forum on the main campus so we are working hard on it.

On Monday, we had soft openings. Faculties came and playtested our product in virtual reality. We also guided them through the PC prototype as well and explain the student’s learning experience step by step. The faculties gave us a lot of valuable advice, including some minor bugs we found during the playtest and adding the feature that the students could have the opportunity to choose which step they want to start with.

For the programming part, we finished implementing all the textures on the lighting. We also have adjusted the environment lighting to make it as realistic as possible.
We also have changed the beginning tutorial and also the ending scene to make the experience more consistent.

For the arts, our artist has also finished polishing all the small interactable objects for the experience.

For the PC parts, we worked hard to finish the most difficult part, the leveling, before Friday, and we made it.

On Friday, April 26th, our client, Sandra, came to visit us and gave us her final suggestions about our project before the end of the semester. Sandra was happy about what we have achieved this semester and she would love to see us showcase our project at the forum.

We showed our PC prototype to the client.

We presented our VR prototype to the client.

Week 13 Dev Blog

It is only one week left before the soft opening. We are wrapping up our deliverables for the soft opening. Our project consists of two components: the PC version and the VR version.

In the PC version, there are only 4 steps need us for the Unity Interactions. Because we need to build up our Unity interactions based on the website framework done by HCII, we could only finish 2 steps out of 4 before the soft opening. However, we will make sure that we will deliver a complete product by the end of the semester.

Here is a peak of our PC demo for the first 2 steps:

Week 12 PC demo

Our artist has finished adding the textures of the machine and some interactable items. The programmers have implemented the new textures and let’s take a look:

Machine Animation

We also fixed a few bugs but there is no time for a big change or implement new features for the VR version. We are ready for the soft opening.

Week 13 VR Demo

After the soft, we will modify our prototype based on faculty’s feedback. We will also finish the PC version and start writing documentation before the final delivery day.

Week 12 Dev Blog

After gathering all the feedback from the playtest sessions last week, we fixed and improved a lot of parts and were ready for another round of playtesting. On April 9th, 6 ETC students came and playtested. We were glad to see how our modifications improve the experiences. The follow-up questions were the same as last week and our goal was to collect more information from them.

Based on their feedback, we improved our VR training and were ready for the client’s onsite visit on Friday, April 12th.

On Friday, April 12th, we showed our client, Sandra, the latest VR demo. She also tried it with the hint turning off.

VR version in Week 12

We collaborated with the researcher from HCII for our PC tutorial. Team Hot Metal is responsible for all the interactions in Unity and implementing the communication of interactions to TutorShop. The research from HCII is in charge of PC instruction and HTML implementation. During the client meeting at week 12, we presented “step 4: EOS Layout Inside” of our PC version.

PC version – step 04 EOS Layout Inside

We found out that building up and improving the PC version is far more complicated than we expected, while we only have one programmer responsible for this part. We are confident that we could finish the PC version by the end of the semester. However, by considering its quality and quantity, we are afraid that we could only finish half of them for the Soft Opening.

The semester is coming to the end. Our project is content-heavy with an overwhelming workload, but our team is going to work harder to achieve our goal for the following weeks.

Week 11 Dev Blog

In week 11, we have built a complete version of our VR training and were ready for playtesters. Throughout the whole week, we conducted ten playtest sessions. Among them, there are ETC faculties, ETC students and Ph.D. students from the client’s lab. Our target audience is graduate students at engineering school so we are very selective on the background of our playtesters. ETC students and faculties share a similar background with a decent amount of VR experiences so their feedback focuses on the understanding and intuitiveness of our VR training. Students from the client’s lab could help us correct the clearness of the procedures. All of their feedback are quite helpful for us to improve later: Here are some of the photos during playtesting:

Playtester #1 – ETC student
Playtester #2 – ETC Faculty
Playtester #3 -Ph.D. student from client’s lab
Playtester #4 -ETC student
Playtester #5 – non-ETC grad student

Before the playtest, we gave them a brief introduction about our project:

“We are team Hot Metal. We are working on a VR tutorial of a 3D metal printing machine for CMU Engineering Department. What we are going to show you is our latest VR demo, which will be used for engineering students after they took the class and got enough knowledge from our PC tutorial. This demo is supposed to be played by the students who have already learned the operation. So if you are confused, let us know.”

One student acted as a guide to help them go through the demo if the player needs help and two students were observers who wrote down everything they saw during the playtests.

After the playtest, the observers asked the players the following questions:

  1. Do you know what you are doing during the playtest? If no, then why?
  2. Are all instructions clear for you? If no, what are they?
  3. Do you have trouble finding some objects? If yes, what are they?
  4. Do you understand the controllers’ interaction? If no, then why?
  5. Do you feel you are learning something from the experience?
  6. How do you feel about the sound effects?
  7. Do you have any other suggestions or confusions?

We found playtest very helpful for our projects. Based on the observations and feedback we got from the playtest, we could not only find out our programming bugs but also our design defects. Now we are very clear what we need to improve next week.

Week 10 Dev Blog

In Week 10, we continuously polished our VR project based on the feedback from clients’ visit last week. We set our goal of the week on Monday:

1.  showcase a small interaction between website and Unity

2.  polish and modify the problems we found listed above and get the VR version ready for playtest

3.  lock in what we are going to deliver by the end of the semester and what does the scope of work in the summer gonna look like

We worked hard on trying to make the experience more intuitive and smooth while putting our clients’ suggestions into consideration. Our programmers are continuously working on the VR demo to prepare for the playtest next week.

We changed the interaction of doors and switches in the scene. Instead of dragging the door by the edge, the guest can now click on any part of the door to open or close it automatically. The algorithm is shown below:

Screenshot of Outer Door Controller
Screenshot of Inner Door Controller
Screen of the Switch on the Inner Door

Here is the latest build we had at Week 11.

VR demo of Week 11

Besides the VR version, our team also communicated with the researcher at HCII about their needs from us in the PC version. After discussion, we set our scope of the PC version, which includes the Unity Interactions of these 4 specific steps:

04: EOS Layout Inside Machine

06: Mounting and Leveling of Build Plate

07: Cleaning Lens-Double Check all Setup Conditions

08: Start Build

We will also be responsible for Implementing the communication of interactions to TutorShop and the researcher at HCII will be in charge of PC instruction and HTML implementation.

In conclusion, our project is making progress every day and we are looking forward to our first-ever playtest session next week.

Week 9 Dev Blog

In order to make up the 5 days we are going to miss for GDC, we chose to work on our project for the fisrt 5 days of spring break.

We went through the feedback we got from our half presentation. We are confident that since we have finished our VR linear experience, without the final art assest, by the end of week 9, we can finish our project on time by the end of semester. For the hinting, beginning on week 10, we will inivite the students both in the NextManufacturing lab and in ETC to playtest our prototype. We will iterate and modify our design according to the playtest feedback.

For the programming part, we continuously finish up and debug our build. We use placeholder for safety equipment and implement our latest 3D model into our current build. For the art part, our artist is working on unwrapping our 3D model before adding texture on it. Let’s take a peak:

Our designer starts to work on the PC design but we still need to talk more about the requirments from our clients.

On Tuesday, March 12th, our clients, Sandra, Bruce, and Lu come to ETC and we present our latest demo to them.

Bruce playtesting our demo
Discussion at client meeting

Bruce playtesting our demo

Week 8 Dev Blog

In week 8, we mainly focused on our half presentation. We divided our presentation into different parts and each person is responsible for their delegated slides and presentations. We rehearsed several times throughout the whole week.

We talked about our project goal, design progress, level management, CTAT implementation, 3D model and our future plan for the rest of the semester. We did a pretty good job on the presentation.

On the day of our half presentation, March 7th, Nick, the lab technician, John, the Ph.D. student and Lu, the HCI researcher, came to watch our presentation. We also presented our latest demo to them. They are very satisfied with our presentation. They think it is well rehearsed and informative. Nick and Todd also provided some minor suggestions about our current build. After the half presentation is done, we could focus back on our VR build.

Nick playtesting our demo

Nick playtesting our demo

Week 7 Dev Blog

During week 7, our team is still focusing on the VR version. Our artist has made significant progress on the model of the machine. Now it is completed with two doors–one inner and one outer, plus the monitor and the small table on the right-hand side of the machine. Here are the screenshots:

The side view of the machine
The straight view of the machine
The tools that are used during the procedure

Our programmers continuously worked on step-by-step procedures. We have implemented the text instructions on the tablet and the highlights for the hinting purpose. We also have added name tag on each object the student touched to provide more information for the students. Here is our demo video recorded for week 7 client meeting.

During week 7, we also had several groups of people came to visit our project. On Thursday, February 28th, we had Heather Kelley and John Sharp coming and they provided a lot of suggestions about how to display text information in the VR environment.

On Friday, March 1st, representatives from Deloitte Digital and Anthony Daniel both came and expressed interests in our project as well. Deloitte Digital showed us what they had done similar to our project. Anthony Daniel also played our current build and addressed several concerns about the design of the tablet. We will put these suggestions into concern and improve in our next version of the build.