Team:Cornell NY/Demonstrate

Variant HTML Builder by Medium Rare

Header 2 Open navigation

Overview

Components

  • App
Iodine Sponge Applicator

Cold Shock

Temperature Sensor

UV Lights

Silicone Liner

Design

Compiling the qualitative data we got from farmers, we reconvened during our brainstorming sessions and were able to analyze the interviews using an empathy map, which organizes needs, insights, frustrations, values, thoughts, actions, and feelings of the user. Using this, we developed a problem statement, which was used to drive our design process:

Problem Statement:

“Farmers need to prevent mastitis because they need to save money”

With this idea, we proceeded to complete similar design processes on the individual components, and determined that the best modules to pursue and build would be a temperature sensor (for detection of infection in udder), UV light sterilizer (to prevent bacterial growth), cold shock (to aid in natural teat closing), and iodine applicator (to make more efficient the existing practice of “post-dipping” the cow teat in order to disinfect and prevent infection). Using tables of needs and specifications for each of these modules, we were able to hone our design concepts and drive the design of the modules individually.

Our design underwent many iterations, and most design changes were direct results of farmer feedback. Our human practices subteam worked diligently to always keep the user involved in the design process at every stage to allow us to quickly adapt to new ideas, needs, and concerns.

Design of the modular milking machine shell was carried from concept to the real world by using computer assisted design (CAD) software and rapid prototyping techniques like 3D printing, laser cutting, and metal machine shop usage.

Designs were also altered with consideration to engineering models and calculations. Check out the modeling page in order to learn more about our practical engineering work.

Fabrication and Assembly

Several iterations of the milking shell prototype were built from 3D printed material using Makerbot and Objet30 Pro printers. At this stage, the various components were tested for fit and functionality. These components were made of VeroBlue plastic with an inner diameter of 1.5 inches and an outer diameter of 1.75 inches. The shell was designed modularly in two sections: the bottom piece had notches printed near the top edge for alignment and attachment to the other modules, while the top module had L-shaped grooves for the notches to slide into. This L-shape was chosen for its alignment and twist-locking mechanism.

The final milking shell prototype was machined from Aluminum 6061-T6. Instead of machining notches onto the aluminum tube, holes were drilled and tapped for M3x0.5 set screws. These were set into the face of the main module to provide a notch-function for the twist-lock mechanism. The functional components were all set in the faces of their respective modules using M3 bolts. All machined parts were made in the Cornell Emerson Lab, and all parts were assembled in the Cornell Project Team Labspace.

The Iodine Sponge Applicator consists of arms that are fastened on opposite sides of each other on the shell with 2 steel brackets on each side of one arm. M3 bolts secure the brackets to the modules and the arms to the brackets. Removable sponges that can be pre-soaked with iodine are attached to the tips of the arms. The reusable sponges will come with the device, and the arms are machined out of aluminum.

Testing

Sanitation testing:The UV-C lights were turned on for 7 hours and left to disinfect a 3x4 inch area of silicone with a thickness of 4mm. The material we tested is the same material as the milking liner, however, the thickness was about two times as thick (milking liners have thickness of 2.0mm). The silicone was divided into 20 sections, and left to be disinfected by the UV lights. At certain time intervals, a particular section of the silicone sheet was swabbed and streaked onto a LB plate using a sterile cotton swab. The plates were incubated for 49 hours at 36.7oC. Once incubation was complete, the number of bacteria colonies were counted and recorded. The results are as shown.

A control test was conducted to test any contaminations in the air or the water used when swabbing the silicone.

The results of our experiment are inconclusive as our data has no trend, and the effectiveness of the UV lights require further testing. There are a couple possible sources of error during our experiment. Various team members swabbed different plates, so there may have been disparity between swabbing techniques. Some members may have swabbed different area sizes on the silicone piece or streaked their plates in slightly different manners. Another source of error was the thickness of our liner. The silicone sheet we used was twice as thick as milking liners, so this may have affected the amount of light penetration through the liner, thus varying the effectiveness of the UV disinfectant. A third possible source of error is the water we used to dampen our cotton swabs before swabbing the liner. The water may have gotten contaminated over time from being exposed to bacteria in our surroundings and the air.