Fall 2020 Design I Final Competition

Section Z: Team A

Problem Statement: The cleaning procedures at Mines are flawed and creates multiple opportunities for the COVID-19 virus to spread.

Team Members: Alessandro Amparan, Katherine Latiolais, Bridger Mobley, Ruddock Smith and Alexander White

Instructor: Kelly Pickering


  1. I love the idea of multiple cleaning stations around the classroom. Couple of questions
    1) Top pump bottles have been around for decades and widely used in medical and industry settings. In fact I just ordered some last week for my electronics lab — use pure grain alcohol to clean circuit boards. Why reinvent the wheel when the top pump bottle already exists? Link: https://www.all-spec.com/Product/35608-34174?gclid=CjwKCAiAiML-BRAAEiwAuWVggi8CYC5MQ3UVS8p3y17jqZNiVARTHHnuf05RX6_ct-jSG7pBnnYu1RoC_KkQAvD_BwE
    2) Does your pump system require power? If so, how much and what is the source?
    3) You recommend 3-D printing the clamp system. What is the size of the clamping system? What is the typical bed size of a 3-D printer?
    4) What was the 3-D printer print time?
    5) In classrooms with desks and not tables, where do you recommend placing the systems?
    6) How much downward force do you anticipate being exerted on the dispenser? Did you validate your clamp can sustain the force?
    4) Please identify the different subsystems that team members worked on

    • Hello Professor Bodeau,

      Thank you so much for your questions, we all collaborated to give you these answers:

      1) Our bottle is comparable to the one linked, with the exception of price. While the bottle linked costs about $7.50, ours costs closer to $4.00. In addition, we can manufacture the top-dispensing cap separately and retrofit it to the existing bottles at Mines, bringing costs to about $1.00 per bottle. Another thing to note is that the cap can be retrofitted to a bottle that can hold a much larger amount of sanitizer in comparison to the one you showed us.

      2) 3-D printer beds, including the ones at Mines, are on average 6” x 6” x 6”. Each individual subsystem that is 3-D printed is designed to comfortably fit inside these dimensions. The dimensions of the housing are 18” long by 3” tall. In the final design, we intend to construct the frame out of sheet metal instead of 3-D printed parts to provide greater structural integrity for the whole design. For our prototype the frame was made out of 3 3-D printed components that were bolted together.

      3) From our CURA slicing estimates, our final prototype would take about 20 hours to print. Additionally, we have designed slicing files that can print all the parts in a single print, saving a lot of time and effort.

      4) Our bottle pump does not require any power. The pump itself is very similar to that of a lotion bottle pump. When the actuator is pushed down on, sanitizer is dispensed out the top and onto the paper towel. To touch on the more of the pump’s internal workings: as the actuator is pushed down on, the piston inside of the pump housing shell is displaced downward. This movement compresses the spring inside the housing, which pushes a small metal sphere downward to seal a small opening at the bottom of the housing shell. This movement pressurizes the pump. When the actuator is released, the spring and sphere are moved back to resting position, releasing the built up pressure. The pressure release is what draws sanitizer up the tube and into the pump housing shell for the next use.

      5) The product could be mounted at the end of a few desks. This way it doesn’t take up too much space and puts the product at a convenient location for the students at surrounding desks.

      6) From in-house results we expect about 5lbs of force to be exerted on the bottle and holder. Unfortunately, the shutdown of in-person classes prevented us from testing on a larger scale, as we were hoping to. However, the prototype held up testing from the usage of team members and multiple students.

      4) Subsystems that team members worked on:
      Bridger Mobley designed the overall frame of the design
      Katherine Latiolais designed the top-dispensing bottle
      Ruddock Smith designed the bottle holder
      Alexander White designed the clamp subsystem
      Alessandro Amparan designed the paper towel holder

  2. I love the idea of more cleaning stations positioned in the classroom. Couple of questions
    1) Top pump bottles are widely used in medical and industrial situations. In fact, I ordered some last week for an electronics lab — use pure grain alcohol to clean circuit boards. What is the advantage of your bottle over bottles already manufactured. Example to current solutions: https://www.all-spec.com/Product/35608-34174?gclid=CjwKCAiAiML-BRAAEiwAuWVggi8CYC5MQ3UVS8p3y17jqZNiVARTHHnuf05RX6_ct-jSG7pBnnYu1RoC_KkQAvD_BwE
    2) You recommend 3-D printing the housing. What is the size of your housing and what is the size of a typical 3-D printer bed?
    3) How much time did it take to print?
    4) Does your pump bottle require power? If so, how much and what is the source?
    5) In classrooms that have desk configurations rather than tables, how do you recommend configuring your system in the classroom?
    6) How much downward force do you expect on the pump bottle? Did you validate the housing clamp can sustain that force?
    7) Would the installation impede egress and do you anticipate approval from the fire department?

    • Hello Professor Bodeau,

      Here is the response for number 7.

      7) Barring some very unwise installation, we do not think the design will impede egress or disrupt regular traffic flow. The design is small, slim, and low-profile, only extending from the edge of the table a few inches. We do anticipate that the fire department would have no issues with our design due to the compact design.

  3. Team A –

    Nice work. You certainly highlighted a number of critical points of failure in the current process at Mines.

    1. I feel there is still an education component here. I like the innovative top-push dispenser; however, students could use a paper towel with the current spray bottles already around campus. Do you see the biggest problem in educating the stakeholders of appropriate conduct? Or in the type of dispenser?
    2. I also agree, one station per classroom prohibits the ability for students to maintain social distancing requirements. How many of these would you estimate would be needed on Mines campus?

    • Hello Professor Meyer,

      Thank you so much for your questions, we all collaborated to give you these answers:

      1) You bring up a good point which is that sanitizing the spray bottles would be an alternatively safe way for students to sanitize their surfaces without spreading COVID-19. We believe that proper stakeholder education is the solution to reducing the spread of COVID-19 on campus, however, it is always simpler to design a product that forces users to act in a certain way, rather than hoping they will follow procedure.

      2) The Mines campus has 65 working classrooms on campus. We plan to implement an average of 4 stations per classroom on campus (some classrooms, like lecture halls, for example, would require more, and some less), so that would require 260 stations across the whole campus. However, this calculated classroom count does not account for non-classroom spaces such as computer labs, the library, the student center, etc. To include these spaces in our station requirement, we decided to add an additional 25% of the 260 classroom stations. This would bring us to 325 stations implemented across the Mines campus.

  4. Thank you for your presentation.
    1. Is there a known transmission rate when infected people touch surfaces? How long does the virus survive? In other words, what is the risk of not wiping down a surface?
    2. Great video showing examples of the problem as it exists today and transitioning to how your solution solves it.
    3. What is the cost to CSM for each student who gets infected by COVID-19, and if you were to even get to, say, 50% of students to wipe down their desks how would that lower the infection rate at CSM? In other words, did you run a cost-benefit analysis to justify CSM deploying your product?
    4. I get disappointed when I go to the grocery store and find that there’s no bags for produce. How would you address keeping all of those stations filled with materials?
    5. What would be a good way to convince students to wipe their desks? Were there reasons given as to why students wouldn’t clean their desks? How could you measure the success of your stations if they were deployed?

    • Hello Professor Quesada,

      Thank you so much for your questions, we all collaborated to give you these answers:

      1. It is known that COVID-19 can survive up to 3 days on plastic surfaces. Due to COVID-19 being such a new virus, exact transmission rate from surfaces is not known, and studies are still being done. But since COVID-19 can live on surfaces for a long period of time, it is vital that students wipe down their work surface. Additionally, students should not need to put themselves at risk of infection, no matter how slight the chance. Ultimately, even if it’s not dangerous, the policy to clean shared surfaces with a shared spray bottle is counterproductive, and as such needs addressing.

      3. When quarantining a student that lives on campus, Mines will have to pay to house the student in a quarantine room, deliver the student meals, and have the student participate in multiple COVID-19 tests. From estimating these prices, as well as researching the expenses from other universities, we estimate that quarantining a student costs about $800. Also, this does not include the cost of taking multiple COVID-19 tests, which would cost the school an additional couple hundred of dollars. We believe the infection rates at Mines would decrease significantly if the student population was more diligent about following proper procedures. And since we think our solution would help reduce the spread of COVID-19, Mines would benefit because they will pay less for quarantining students. Additionally, COVID-19 infections have increased greatly on the Mines campus. There have been a total of 382 cases on campus since August 17. In response, Mines now requires students to participate in 2 COVID-19 tests per week. This doubles the cost of COVID-19 tests for Mines. If our product was implemented around campus, causing a decrease in infected students, Mines would not need to test as frequently, saving time and money.

      4. I think we can all relate to the frustration of empty stations, at the store and in the classroom. However, multiple stations around the classroom means a greater stock of materials than a single station at the front. If the current single station runs out of paper towels, the user is unable to wipe down their desk. If one out of our stations runs out, the user can just grab some from the next closest station. The stations will continue to be refilled by the custodial staff and it is essentially up to them to refill the stations regularly. If empty bottles were not being refilled properly, they could be put at the front of a classroom to indicate they need service.

      5. We found from our stakeholder interviews that students don’t wipe their desks due to the inconvenience and limited amount of time they have before class starts. This product would be a good way to encourage students to sanitize their desks because it puts the sanitation materials much closer to the student, adding convenience. The success of this product is measured by how many students consistently use it compared to Mine’s current system. This is tested by installing these stations in classrooms and observing how many students sanitize their workstations before and after class. Our product would be considered successful if a higher percentage of students sanitize their workstations in the classroom with our product as compared to our field research.

  5. Nice prototype and CAD work!

    A few questions….

    1) Where did you get the costs of present cleaning stations?
    2) The spray configuration…. did you compare the amount of disinfectant in this design vs the side design? Would it take more time and pumps to cover the same amount of table?
    3) Any issues with the topside dispensing?
    4) Expand on the 157 students surveyed?
    5) Will this design add to the maintenance teams work load?

    I look forward to your response.

    • Hello Professor Wetzel,

      We encountered an issue with the reply button, you should be able to find our response to you in the comment below this post.

      Thanks for your understanding.

    • Thank you for your thoughtful responses, Good luck in the competition.

  6. Thanks for Your questions Professor Wetzel,

    We all worked together to give you these responses,

    1) Currently, the present cleaning stations at Mines consist of 3 different components. There is the paper towel roll dispenser, the spray bottle, and the wall mount for the bottle. We are also assuming that Mines probably got a huge discount on these items from buying bulk from a supplier, so our estimated costs are 25% off the retail price.

    Spray Bottle – $3.00
    Spray Bottle Wall Mount – $3.25
    Paper Towel Roll Dispenser – $45

    One thing to note from our estimations is that paper towel dispensers have been extremely difficult to acquire in 2020. This has resulted in a large cost increase due to demand. We have yet to find a supplier that has the same dispenser at Mines in stock, so instead, we averaged many of the current retail offerings for paper towel dispensers and deducted the 25% to land on $45.

    2) While our prototype solution has a smaller bottle, the sprayer itself can be retrofitted to any bottle, including the ones that already exist at Mines. Additionally, our solution only takes about 3 pumps to get enough sanitizer to cover an individual’s work surface. In comparison, the spray bottle takes about 2 pumps, so there is barely a difference.

    3) During testing, we did not discover any major issues with the design. It did take an extra pump to saturate the towel, but on an individual basis, this takes a miniscule amount of extra time. We also found that the spray pressure was lower than a standard spray bottle. However, this did not inhibit the function of the device. We believe that design has way more benefits than cons because of how it eliminates a shared surface in the classroom. The only concern we can think of is how the bottle would last over a longer period of time.

    4) The 157 students were observed from 6 different in-person classes. During these classes, the sanitation stations were watched and the number of students that used them were recorded along with the total number of students who avoided them.

    5) We believe the impact on the maintenance team work load would be minimal. While there are more stations to be filled, the total draw on resources (paper towel, cleaning solution, etc.) remains the same per classroom. Even if it takes 5x as long to fill all of our stations, they’re doing it ⅕ as often as they do for the current ones, which cancels out the amount of maintenance required.