The Oreo may be milk’s favorite cookie, but judging by the long lines inside Siebel Center, a CS @ ILLINOIS senior design project was a favorite exhibit at Engineering Open House (EOH) in March. Known as SugarCUB3D, the popular project mixed introductory programming concepts and 3D printing with America’s best-loved cookie.

CS seniors Han Chen, Anurag Choudhary, Sukeerthi Khadri, David Naber, and William Xie hacked a 3D printer so it would automatically dispense a person’s initials in cake frosting, Nutella, or pudding on an Oreo—a well-deserved reward for answering questions about basic programming.

According to Naber, the project’s goal was to get kids interested in computer science, so he and his teammates created an interactive website where the kids could answer questions about basic computing operations. “Kids love sugar, and what better way than to get them interested in CS than through food,” said Naber, who designed the website’s user interface and did front-end development with Choudhary.

Chen and Khadri designed the back end of the site, including the database from which the site drew quiz questions. Chen also wrote a script to automatically generate 3D models in model (.stl) and machine-code (g-code) format, which included all 702 initial combinations they might encounter at EOH.

As hardware-software liaison, Xie created the communication layer between the website and the printer, and he led the modifications to the Ultimaker 2 Extended printer. A typical 3D printer has a tip that heats up and melts plastic and then dispenses it in very thin layers. By drilling a second hole through the print head, the team was able to connect the printer to a Discov3ry Paste Extruder and use its nozzle to direct the icing precisely on the cookie.

The students published their source code and project notes as a widely accessible open-source project so others can benefit from their efforts, and Naber created a promotional video about the project.

“Food printing is an interesting vehicle to communicate about computer science because there is physical movement and there is something edible too,” said CS Senior Lecturer Lawrence Angrave, who developed the idea for the project and supervised its completion. “Both these qualities make food printing a memorable experience and therefore a great way to playfully introduce computer science.”

In the fall, Angrave looks forward to having another team of students pick up with the project and continue to innovate. “This semester's students have set a high bar, so it will be a tough act to follow, [but] I'm planning on making the project open-ended, so I'll be excited to see the ideas and implementation by next year's senior project undergraduates,” Angrave said.

As for this year’s team, two of the five students have accepted full-time jobs as software engineers after they graduate in May—Khadri will be working at Capital One and Xie is going to Expedia. Naber, who is minoring in art & design and cinema studies, will be working as a product management intern at app-maker Whisper this summer and will graduate in December. Chen and Choudhary will spend the summer interning as software engineers at Amazon and NextCapital, respectively; both will graduate in December.

The Oreo 3D printing project was one of many projects in the CS 492/4: CS Senior Projects course, which most CS seniors take during their last two semesters. Run by CS Lecturer Mike Woodley, a former Microsoft employee, the capstone course challenges student teams to use their computer science skills and knowledge to create and deliver a complete software/hardware project for a client such as a U of I faculty member, government or non-profit agency, or company.