Team:Cornell NY/Demonstrate
The Milky Way
A Modular Customizable Shell
Overview
Legendairy’s mechanically engineered device works to prevent mastitis on dairy farms. We conducted an extensive design thinking process, using ethnographic research and human centered design methods, and discovered that farmers were most concerned with prevention of mastitis. Using the technology already being used on farms and modifying it to provide value while maintaining user comfort and familiarity, we developed a modular, customizable milking machine shell. The milking machine shells currently being used on dairy farms only consist of a rolled steel tube in which a milking liner and vacuum pump are connected in order to milk the cow. While this design was functional, it did not provide any disease prevention functionalities. We sought to introduce a new technology to replace the standard shell. Our solution is a modular shell, which is customizable with disease-prevention modules of the farmers’ choice. Farmers can choose modules which they think would be effective on their farms, and assemble customized shells.The available modules are automatic post-dip, cold shock, temperature sensor, and UV sterilization modules. The automatic post-dip, UV sterilizer, and cold shock are used to prevent mastitis while the temperature sensor is used for preventing mastitis from getting too severe. To ensure that our product is usable for all farmers, our prototype is compatible with the dimensions of standard milking liners.
The idea for the modular milking machine shell was conceived after an extensive design process. We used the same design thinking techniques as IDEO, the famous design firm, and those taught at Stanford University Design School. Our product development subteam worked extensively to teach themselves the design thinking method, and combining this with engineering design principles taught in the Cornell Engineering curriculum, used a design method which allowed us to design the best possible device to meet the needs of dairy farmers.
The design thinking process utilizes human-centered design and ethnographic methods to determine the needs, concerns and frustrations of the user. Our end user was the dairy farmer, so we set out to learn everything about the dairy industry, daily dairy farmer life, milking practices, and technology used on farms. We interviewed farmers on many different farms and got to learn about what they deemed important in their line of work, especially when dealing with mastitis.
Components
The modular milking nozzle combines the familiar shape of a milking nozzle with a few extra features to make the milking process effortless. The nozzle is broken up into two sections: the bottom section holds the cold shock module while the top section holds everything else.
Iodine Sponge Applicator
Designed to help prevent mastitis by quickly coating the cow’s teat in iodine while the nozzle is removed from the udder. Research has shown that the number and types of bacteria on teat skin are directly related to the frequency and type of mastitis that develops, and iodine dips are widely accepted as an effective way to reduce bacterial populations on teat skin and reduce the incidence of mastitis by 50%. With a simple squeezing mechanism, the sponges will be lifted up to the top of the liner and will evenly coat the teat of the cow as the milking nozzle is pulled away. notifications.
Cold Shock
Utilizes a Peltier Device running at -15°C to cool the liner inside and to contract the muscles in the teat. Research has shown that the most vulnerable time for cows to contract mastitis is right after milking, because the teat can stay open for up to an hour after milking, all the while allowing bacteria to infect and infection to spread. A copper wire is used to facilitate heat transfer.
Temperature Sensor
Features a thermistor that can measure the temperature of the udder. A common symptom of mastitis is a small increase in udder temperature due to inflammation, which usually occurs before noticeable changes in milk. The thermistor can sense the elevated temperatures with a microcontroller, and send the information to the smartphone application developed by our CS/ECE team, which will in turn notify the farmer that the cow being milked may have mastitis.
UV Lights
The UV lights in the top module consist of UV-C lights, typically used for disinfection. The lights are connected in parallel and powered by a microcontroller. To ensure that our UV light disinfects the liner, we have developed a translucent silicone liner that allows light penetration.
Silicone Liner
Molded using Smooth-On Mold Star 20T Silicone Mold. The translucent material allows for UV light penetration through the liner. This allows for disinfection of the liner after milking, reducing the spread of bovine mastitis from cow to cow.
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”
Noting this problem statement, as well as all the important data we had collected, we created a table of needs and specifications, which is a list of things our final product had to accomplish, as well as a set of standards we developed for each one of the requirements. This engineering design technique was paramount in focusing our design towards a specific goal and allowing us to brainstorm specific solutions to the problem at hand.
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
Connection testing: All connections for electronic components were tested using an Arduino microcontroller. The thermistor was tested by using a can of compressed air to cool the thermistor. We monitored the change in temperature to see how accurate the readings were.
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.
Future Work
Product Development’s future work will involve improving design for mass production and programming the different modules to make them compatible for all milking machines. Further work improving the design of the milking nozzle will need to be completed to ensure all modules are housed safely within the shell. Additional testing will need to be conducted in order to gain FDA approval for the milking nozzle and to test if cold shock would successfully close up a cow’s teat.
