Senior Design

Week 5: High Fidelity Prototyping and Refined Testing

Posted on by Edward Ndonyo

This week marked a transition from proof-of-concept to high-fidelity design as we advanced both the Kangaroo Cable Management and Giant Cheetos Machine projects. With deeper testing, better tools, and a clearer understanding of our design needs, we focused on refining both function and form.

iKMC Cable Management : Toward Final Prototypes

We began by iterating on our IV stand clip design, shifting away from the use of Velcro to explore more durable, adjustable fastening mechanisms. Our goal was to enhance long-term usability and reduce material fatigue from repeated use.

To ensure our final product would be clinically safe and manufacturable, we researched medical-grade materials suitable for hospital environments. This helped guide our decisions for the next stage of development.

We then transitioned to mold design, where we started creating a positive mold using 3D printing. This printed mold was then used to form a negative mold from silicone, which brings us one step closer to producing a soft, flexible final version of the clip using appropriate materials.

Another exciting development this week was receiving training on the laser cutter machine. We learned how to design parts and operate the machine, which opened up new possibilities for precision-cut components that will support both functional testing and aesthetic refinement.

Giant Cheetos Puff Machine: Moisture, Torque, and Feeding Flow

With the new smaller motor wheel installed, we resumed extruder testing this time focusing on how moisture content affects product consistency. The results were clear and promising: lower moisture levels produced puffed, brittle, and audibly crispy Cheetos, confirming our earlier hypothesis that low torque was the main issue.

We performed tests at 15%, 10%, 7%, 5%, 2%, and 0% moisture levels, carefully observing each batch’s extrusion quality and physical properties. The improved torque (though still not ideal) led to visible improvements in puffing and texture. However, we observed significant improvements in puffing and texture as moisture decreased with the best results achieved at 0% moisture.

Our next step is to design a controlled feeding mechanism that will provide a consistent flow of grits and help maintain optimal operating conditions. This refinement is essential for achieving reliable, repeatable Cheetos production.

Both projects are pushing us to think critically about real-world constraints from mechanical force to material safety  and refine our engineering solutions with every test and iteration. We’re getting closer to robust, field-ready designs, and each challenge brings us one step further.

 

 

Week 4: From Design to Function

Posted on by Edward Ndonyo

As we move further into our projects, this phase has been all about turning design concepts into physical prototypes, testing their performance, and making critical engineering decisions based on real-world constraints.

iKMC Cable Management: From Concept to Clip

Following valuable feedback from our supervisor, Dr. Kevin Holmes, and our client, Elisha Sanoussi, we revised our initial design by incorporating a clip-to-clip mechanism. In this design, a primary clip attaches securely to the mother’s garment, allowing secondary interchangeable clips to snap into place and hold various medical cables, such as IV lines, CPAP tubes, and NG tubes.

We successfully 3D printed the first versions of both the IV stand clip and the garment clip using a variety of materials PLA, PTU, and ABS to evaluate strength, flexibility, and durability. The IV stand clip can accommodate at least six tubes, while the garment clip holds up to three, allowing better cable organization and supporting comfortable, uninterrupted Kangaroo Mother Care.

After assembling the clips, we tested them by attaching different types of tubes to observe how well they held under simulated use conditions. This helped us understand how the clips perform when subjected to real-life tugs, bends, and movements.

We also conducted Design Review 2, where we presented our improved prototype, shared observations from testing, and received feedback on further iterations. One important suggestion from the review was to make the clip-to-clip design more modular, allowing the garment clip to hold various shapes and sizes of interchangeable cable holders. We are now continuing to iterate on the mechanism to enhance its usability and versatility.

Giant Cheetos Puff Machine: Addressing Speed and Torque

On the Cheetos side, we tackled one of the most significant mechanical challenges: the extruder’s high speed causing low torque, which directly affects the consistency and performance of the puffing process.

Our motor, rated at 3450 RPM and 5 HP (3.7 kW), was running the extruder at approximately 2495 RPM. However, through testing and research, we found that optimal puffing requires an extruder speed of just 350 to 500 RPM. The excessive speed not only leads to low torque but also causes product inconsistencies and motor strain during operation.

We evaluated three potential solutions:

  1. Purchasing a lower-speed motor with a 1440 RPM rating,
  2. Installing a Variable Frequency Drive (VFD) to regulate motor speed,
  3. Changing the size of the pulleys/wheels to adjust the speed ratio.

We chose to pursue the third option due to its feasibility and cost-effectiveness. The original system had a 7.7-inch pulley on the motor and an 11-inch pulley on the extruder, resulting in the undesired high RPM. We replaced the motor pulley with a 2.8-inch pulley, which reduced the extruder speed to around 878 RPM, a significant improvement, though still above the target range.

To accommodate the new configuration, we repositioned the extruder slightly to maintain belt tension and reused the same belt. We also filed down the screw head to increase the gap between the screw and die, improving material flow and reducing friction that previously caused stalling. With the mechanical modifications complete, the machine was prepared for the next phase of testing.

Finally, we presented all progress and technical decisions during our Design Review 2, where we explained our speed-reduction strategy, testing observations, and next steps for improving puff consistency through material composition and extrusion control.

These experiences are pushing me to think critically, problem-solve across disciplines, and communicate designs clearly. I’m excited to continue iterating both projects and getting closer to solutions that could make a real-world impact.

 

Technical Triumphs and Team Adventures: A Look Back at Weeks 4-6 of My Internship at OEDK

Posted on by aml28

Hello Everyone!

Welcome back to my blog! I’m Alinafe, and I’m excited to share with you the highlights and experiences from Weeks 4 through 6 of my internship at OEDK. These weeks have been filled with technical challenges, exciting adventures, and memorable events that have shaped my learning journey. Let’s dive into what we accomplished and experienced during this time!

 

Week 4: Gel Modification and Prototype Development

  1. Gel Modification Methods

This week, our main focus was on enhancing the gel used for imaging by modifying its properties to improve its performance.

Unfortunately, this DIY approach didn’t work as planned, leading us to order a commercial air pump .

commercial pump
commercial pump

Despite our efforts, the commercial pump also failed to achieve the desired results.

    • Next, we used a syringe to modify our gel . While this method was somewhat effective, it did not gave us required results.

    • syringe method

  • Electric Stirrer Success:
    • Our breakthrough came with the use of an electric stirrer, which proved to be the most effective method for creating small, uniform bubbles in the gel (Figure 5). This tool allowed us to achieve the precise bubble size we needed for our project, marking a significant step forward.
  1. Prototype Development
  • Testing and Iteration:
    • We created test prints and models using different materials to evaluate their effectiveness ). While Material A  and B did not work as expected, Material C demonstrated clear imaging results, which was a promising development for our project
      Test print model
      Test print model
      Model with material B
      Model with material B

      A Fun Break: Houston Zoo Visit

      During a busy week, we took a break and visited the Houston Zoo:

      • Exploring the Zoo:
        • We saw lions, monkeys, colorful birds, and many other animals. It was a fun and relaxing way to take a break from work.
      • Learning About Animals:
        • We learned about animal conservation and the zoo’s efforts to protect endangered species.
      • Team Fun:
        • It was a great chance for us to relax, enjoy the day together, and share our favorite animals.
        • The zoo

       

       

Week 5: Testing, Reflection, and Client Engagement

This week was a bit quieter due to the Independence Day holiday, offering us time for reflection and preparation for the next stages of our project.

  1. Testing and Client Interaction
    Model creation
    Model creation
  • Model Testing Outcome:
    • We had a meeting to test our models and found that Material A and B did not yield satisfactory results. However, Material C showed potential, leading us to focus on refining this material
  • Client Collaboration:
    • Our client was responsive and supportive throughout Week 5 and Week 6. Their timely feedback and availability for discussions helped us navigate challenges effectively and stay on track with our project goals.
  1. Team Building Activities
  • Bike Ride Adventure:
    • Led by Professor Nodskov, we enjoyed a 3-mile bike ride from the bike shop to the post and back. It was a great and fun opportunity to bond with my team members, enjoy the outdoors, and take a break from our usual routine.
      Bike ride moments
  • Ice Skating Fun:
    • Our team went ice skating at Galleria Mall, organized by Brooke and Rohan . We started off wobbly on the ice but ended up having a fantastic time as we learned to skate and cheered each other on. It was a fun and memorable experience for all of us.
      Beautiful moments

Week 6: Final Model Refinement, Challenges, and NASA Visit

Week 6 was crucial for finalizing our model and dealing with unexpected challenges, including the effects of Hurricane Berly.

  1. Final Model Preparation and Hurricane Impact
  • Model Refinement and Testing:
    • We focused on perfecting our final model for gel testing, making necessary adjustments and conducting thorough tests to ensure it met all specifications.
  • Hurricane Berly Disruption:
    • Hurricane Berly caused significant disruptions, including power outages for off-campus students . While our project materials remained safe, the storm impacted communication and work schedules, challenging us to adapt and find solutions.
  1. Inspiring Visit to NASA
  • NASA Exploration:
    • We visited NASA’s Johnson Space Center led by Rohan and Renee, where we explored fascinating exhibits. Highlights included:
      • Spaceships and Rockets: We saw detailed models of historic and current spacecraft, including Apollo missions and Mars rovers.
      • Mission Control Centers: We got a behind-the-scenes look at the control rooms used for managing space missions.
      • Astronaut Exhibits: We viewed real spacesuits and learned about astronaut training and experiences.
      • Presentations: We attended talks from NASA experts and astronauts, gaining insights into space exploration’s history and future goals .
        One of the interesting things we saw

Conclusion

These past three weeks have been transformative, combining technical progress with team bonding and inspirational experiences. We tackled challenges in gel modification, refined our prototype, and navigated the disruptions caused by Hurricane Berly. Our adventures included a fun bike ride, an enjoyable ice skating session, and an inspiring visit to NASA.

Thank you for following along on this journey, and I look forward to sharing more insights with you soon!

 

Why was I in Brownsville, TX?

Posted on by Malaz

My work was about a revolution

…or if we ignored my unbridled enthusiasm and challenged ourselves to be a tad more realistic – an educational intervention.

More importantly, my work seemed to be an obsession with the word “shocking”. I heard it over and over again. “These are incredibly shocking depictions of wounds.” or more commonly: “ugh that’s gross. It will shock patients.” These sentences formed the harmonies of my introduction to Brownsville, TX.

Now, I don’t imagine most people associate the word “shocking” with the city of Brownsville in any way. And I don’t blame them. Brownsville is a small city of about 200 thousand. Although palm trees line the breezy streets in an air of vacation, the most exciting part of this city is called Sunrise Mall and it has a movie theater showing The Jungle Book to satisfy all of your vacation needs.

Brownsville, TX
Brownsville, TX looks like vacation. But I was here for the word “shocking”.

Don’t let my sarcasm suggest I was visiting Brownsville on vacation – I was, after all, here for the word shocking.

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