ProMono

NASAL PRONG MOLD

📍STANFORD UNIVERSITY 🌍 PALO ALTO, USA & NAIROBI, KENYA 🕔2023-2024

ABSTRACT: Nasal prongs are a vital part of ventilatory devices that help people breathe. In resource-limited settings patients are forced to reuse ill-fitting nasal prongs negatively impacting the delivery of oxygen and causing severe nasal injuries, especially in babies. ProMoNo is a compact nasal prong mold that enables the small-scale fabrication of reusable silicone nasal prongs for babies. 


Mold made from machined aluminum, a turned aluminum rod inset and four steel pins. 

prompt & specs. 

COURSE: ME 318 -  Computer Aided Manufacturing

PROMPT : Make anything to showcase CNC (computer numerically controlled) machining techniques. 

inspiration.

The concept of the nasal prong was informed by two experiences that had highlighted how a lack of local manufacturing potential impact people. 

In 2019, as manager of a university makerspace turned into PPE production facility, I saw first hand how the reliance on global supply chains impacted local clinicians' ability to serve patients. Without local manufacturing sites, small maker environments such as our makerspace worked to fill the gap. Despite the potential for high set-up costs and questions of long-term viability, how might local manufacturing potential be boosted?

2. Global Anthropometric Standards

A lack of local manufacturing potential means that devices used are made externally, potentially without consideration of the unique anthropometric and functionality standards needed by a specific population. With this phenomenon traceable to numerous arenas from pulse oximeter calibration discriminating against people with dark skin, to road safety for women. 


Nasal prongs are a preferred interface for babies in need of ventilation due to their cheap cost and low-invasiveness. Despite these advantages, nasal prongs are associated with injury in 50-80% of babies. Factors associated with these injuries are compounded in facilities with limited consumable & human resources. 

design .

I conducted research to identify the factors that caused injury and created physical features that corresponded with the identified pressure points.  

MAIN DESIGN CONSIDERATIONS & CORRESPONDING PRONG FEATURES. 
FUSION 360 CAD MODEL WITH MOLD HALVES, GUIDING PINS & INSETS

fabrication

PROMONO PARTS

final product.

OPEN MOLD WITH COMPLETED SILICON MOLD 
MOLD IN CLOSED POSITION
MOLD OPEN

testing in Kariobangi

Kariobangi is a neighborhood in Nairobi, Kenya that is home to a large number of artisans. To test the ProMoNo mold, I worked with two Kenyan collaborators (Adam Yawe and Anthony Muisyo) to find artisans who would be open to using the mold to create some nasal prong molds. Within Kariobangi, we found an artisan using a locally made injection molding machine to make spare parts. Using his machines, the artisan drilled an injection hole into the CNCed mold and successfully created over 20 nasal prongs in 10 minutes. 

KARIOBANGI ARTISAN REMOVING COMPLETED NASAL PRONG FROM THE PROMONO MOLD AFTER SUCCESSFUL INJECTION
ONE OF THE 20 PRONGS MADE IN NAIROBI
FAUCET/TAP MOUNT MADE ON THE INJECTION MOLDING MACHINE
INJECTION MOLDING STATION, THE ARTISAN USES MOLTEN SHREDDED WASTE PLASTIC & APPLIED PRESSURE USING THE SHOWN STICK TO 'INJECT' INTO A MOLD

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