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This is another example of great intentions inadequately executed, and the implications of engineers focusing too narrowly on hardware. Engineers without Borders had installed enough water points to suposedly provide freshwater for 80% of Malawi. However, a year and a half later, 40% of these water points had broken down. These were caused by problems as simple as leaking pipes, but because of the lack of availble parts, the local people could not repair these systems themselves and these water systems are abandoned.

What is ironic in a pitiful way is that right near the broken down water points, were American-built water points from 10 years ago, abandoned because of failures in upkeep. Why were there two systems in the same area, using the same technology, failing for the same reasons ten years apart? This illustrates that NGOs need to communicate and cooperate, as to effective use their resources and not repeat the same mistakes over and over again.

The speaker, David Damberger, also tells of the story of when he quit his job in the oil industry to volunteer in India and build water systems for the untouchable caste. His family and friends thought of him as such a hero, but that only fills him with guilt when he found out that a short time after his return, none of those water systems that he had built were still in comission. It was devastating to him, especially because he realized that he had made the same mistakes that he criticized earlier.

However, the main point in his talk was to how Engineers Without Borders is learning from past mistakes. Having realized that placing technological infrastructure into a country in need does not actually solve the problem, they have changed their approach in development.

Now, they do not build water points anymore. They have realized that the role of engineers in development is not simply funding wells and schools. Now, they build spreadsheets and focus their effort on the soft, invisible part of things: training local engineers to make and maintain their own technology and devices. This side does not seem as glorious, and definitely deviates from the role that engineers might be expected to take on. However, this is what works, more so than just dropping off technogical infrastructure without providing means of maintenance and upkeep.

I believe this talk was an interesting illustration of the importance of the social context, while also about the importance of admitting and embracing failure. Even though the donors were quite dismayed to see their generations donations having little long-term impact on developing parts of the world, and it can be humiliating to admit failure so publicly, Engineers without Border has really been learning from their mistakes. They are reforming their approach in hopes of making greater impact in the future.

I would however disagree with Damberger's concluding statement, in that the aid system for him has failed. Those mistakes, I believe, were almost necessary step in showing NGOs and development organizations what is the right thing to do. No one can be expected to get everything right the first time. Instead, I see those mistakes as as a step forward.

This ties back to the Kipling quote I had posted earlier this year--"If you can meet Triumph and Disaster and treat those two imposters just the same." The concept of embracing failure and learning from it the same way as you would do with success is so powerful to me. This quote is the one thing I would ever want tattooed on my body.

#context

First Semester, where did you go?

It’s actually very difficult to believe that today is the last day of classes. I am 1/8 of the way done with my undergraduate career... what?

How do I feel about my experiences in the past four months?

To sum it all up in one word: Thankful.

I am thankful to be at UVA. I am convinced it is the most wonderful place on the planet. It difficult to stand on the lit-up lawn and not get a genuine feeling of happiness and content that originates from the bottom of your heart and sends tingles throughout your body. I still think the Rotunda is magical. I am a self-proclaimed Lawnabee. I love the rich history of the university and the values of community and honor that permeate throughout grounds. I love the opportunities that it offers and the endless means, like fascinating classes and flash sems and friendly professors, through which I can fill my mind with whatever ideas it years for.

I am thankful to be a Rodman scholar. I feel tremendously honored and humbled to be considered a part of this group of brilliant and talented individuals. I have learned so much just from working with them and living with them, and they constantly inspire me to be better. I feel like I can just draw upon their excellence and be motivated to really achieve more than I can expect from myself. What is striking is that despite the fact that these scholars excel, they never fail to be supportive and encouraging. We study together, edit papers for each other, and stay up to the wee hours in the mornings together (weirding out the College kids in our dorms). I have made some of my best friends in the Rodman class and my first semester experience would not have been complete without them.

I am thankful to have chosen engineering, especially considering I had no idea what I was getting myself into. The idea behind my applying to engineering schools was really to leave my doors open so I can delay making a decision about what I actually want to do with my future. But through this class, I’ve learned that the technical knowledge is only a fraction of the true benefits of an engineering background. The most important benefits of an engineering education are the skills of problem solving, critical thinking, leadership, communication and teamwork that you develop along the way. These skills you can carry with you for the rest of your life, even as the squeeze theorem from Multivars eventually squeezes its way out of your brain.

I am thankful for Professor Elzey and the Synthesis Design class, a truly unique, challenging, and innovative classes that, instead of focusing on technical training, emphasizes mind-transforming. Our Synthesis Design class has been so rewarding and my mindset about engineering and design has changed so drastically since I first set foot on grounds. I’ve learned, through experiencing successes and failures of different problem-solving approaches, the importance of forming an appropriate problem statement and the dangers of one that is too broad or too constrained. I now understand the immense open-endedness inherent in engineering problems and the need to develop enough wisdom to make sound judgment despite the uncertainty. I understand the importance of the social context. I have gained a greater appreciation or the responsibility that engineers need to assume for the devices or designs or systems that they bring to life.

These concepts seems so obvious to me now that I can’t believe it was only four months ago that I first started really thinking about them. I wish that all intro to engineering classes were like this.

I think part of the answer lies in the fact that there aren’t that many Professor Elzey’s to go around. I cannot overemphasize the inspiration that he is to me. He always has interesting stories to tell and neat ideas share and wise advice to give. He notices even the smallest details from daily life, amplifies it, and expands it to a fascinating new idea or moral story. Also, he hasn't yet stopped surprising me with the endless number of interesting experiences he has had. I'm just waiting for the day that he starts a story with, "so the other day, I was on the MOON...."

Another thing I appreciate is that he is an effective mentor who just knows how to motivate us, and inspire us to motivate ourselves. He sets very little restrictions or guidelines, as to allow us to push ourselves to wherever we can go. On the other hand, he is always available to provide guidance. My work in this class has not been perfect--nowhere near, in fact. However, I recognize and embrace the fact that I have so, so, so much to learn. And I won't stop doing that.

Professor Elzey conveys and embodies the values of engineering so effectively and has contributed tremendously to the reason I value engineering. Even though I'm not yet sure if I will become a practicing engineer, I am certain that I want to subject myself to whatever work comes with four years of engineer school because I sincerely believe that getting an engineering education will make me a better person. I want to become a better problem solver, more critical thinker, harder worker, more effective communicator. That's the kind of self-improvement I strive toward, because what I aim to do in life is really just to keep learning and apply what I know to make a difference in some corner of the world.

I am also thankful for all those who have made my first-semester the best four months of my life. The new friends, fascinating professors, the beauty of Charlottesville and the air of the University. While winter break is coming up and I am so excited to going home--I miss my parents’ hugs and home-cooked meals and old friends and my old room--I know that a month later when I come back to Charlottesville and I will feel instantly right at home again. This is just that special transitional period in my life where I can exist in two places that both just feel right. And I love it.

These are going to four really great years.

Figure A: Home.

#reflection #THE END

The Role of Technology in the Agricultural Water Resource Management of Tanzania

That was the topic I chose for my final research paper in Science, Technology, and Society. I have thoroughly enjoyed this experience because it was an extensive and in-depth case study on the importance of the social context in the success of a technology. It illustrated to me that technological merit can be completely overshadowed if it is not effectively integrated into society.

A little bit of a background:

Poverty alleviation is a major developmental challenge in Tanzania, but it is not possible without improving the efficacy of water resource management. Not only is there a limited supply of water, but the country cannot effectively utilize available water resources. This is particularly crucial in agriculture, which is by far the greatest water user in Tanzania.

There already exists a plethora of sustainable Water System Innovations technologies, known as WSIs, which were developed to improve the efficacy of agricultural water resource management. However, despite these technology’s success in field testing, they have not been widely adopted by farmers. The challenge thus lies in integrating these technologies in a way that is appropriate for the social context.

I used the Social Construction of Technology (SCOT) theory and an analysis of the relevant social groups to determine the prerequisites for effective integration of WSI technologies into villages in Tanzania. I identified these relevant social groups as farmers, NGOs, and internal change agents.

The differences between farmers and NGOs with regard to values, needs, and goals pose as a challenge. For instance, farmers are poor and need immediate profit to ascertain food security, while NGOs aim to promote long term sustainability. The key therefore is to align these goals. For instance, NGOs may help lessen the financial burden of investment by offsetting the amount of capital involved for adopting WSIS. Governments, on the other hand, can provide lowertaxes and transaction costs on goods related to WSI technologies.

Another breach in interpretation exists due to the the interpretative flexibility with respect to what qualifies as valuable knowledge. The farmers have limited technical back grounds not understand or accept the western scientific thought, while NGOs tend to have difficulty removing the stigma that native, local ecological knowledge is “backwards.”

This gap in understanding must be breached if farmers are to gain sufficient understanding of WSI technologies to adopt them for use. The implementation system needs to provide a platform allowing farmers open access to information. External change agents must actively involve farmers and incorporate their knowledge in the implementation of WSI technologies.

The real key lies in building a partnership between the farmers and NGOs. That’s where the internal change agents on the community level come in. The include representatives, community leaders and institutions, as well as neighbors and relatives. They play a critical role because they have a catalytic effect in the spread of sustainable water use practices in the community. They are capable of bridging the gap between external agents and farmers and fostering the adoption of WSIs. This is critical because WSIs are a powerful tool to increase the efficacy of agricultural water resource management, which is requisite for the further socioeconomic development of Tanzania.

We had the opportunity to present our findings in our discussion sections last week, and a few days later I received the following email from my Professor:

“Yiqi,

“Congratulations! You did such a good job presenting your research paper in your discussion section that you have been selected to make the presentation in this Tuesday’s lecture session of STS 1500. For Tuesday, the presentation can be longer, if you like. I suggest that you keep it at 2-4 minutes. I’ll also allow time for one or two questions following the presentation.

“Since this is not compulsory, I’d appreciate if you would let me know asap whether you are willing to do this. I hope you will say ‘yes’. Let me know if you have any questions. "Deborah Johnson”

I sincerely appreciated this invitation! It will be a great opportunity to share this case study with the rest of my class and get them to realize that technological solutions cannot just be dumped into a community and expected to make things better. Getting people in the community to adopt the technology is a whole other challenge but it’s critical for the effective implementation and application of the technology.

I hope I don’t trip and fall.

#reflection #sts

Learn by Taking it Apart

I would not have been able to guess that a pogo stick has 45 parts to it. It really was a rewarding experience to examine each of the parts and learn about their mechanical properties and what they contribute to the overall product.

One such part is the cotter pin. It’s not at all visible from just looking at an intact pogo stick, but the part is critical in holding up the spring and allowing its compression. Also, even though cotter pins are extremely cheap and simple, they are able to withstand very high loads due to their structure.

Another part in the pogo stick that was interesting to me was the plastic spring attachment. It was a protruding piece of plastic attached to one end of the spring, and the stamped metal clamp secured the spring onto the frame using that plastic attachment to hold the spring. Before taking apart the pogo stick, I thought that maybe a metal extension at one end of the spring served that purpose. When I first saw the plastic piece, I thought that maybe an extra length of spring, or a metal extension off the end of the string would be a more convenient way to fulfill that purpose. I thought maybe that a mere metal extension would have been easier to manufacture. However, I learned that that was not the case after figuring out the manufacturing of the spring. It is done by spiraling cold-winding steel around a mandrel. To put on a metal attachment, a metal cylinder or the like would have had to be welded on afterwards. This is an extra step in the manufacturing process, and it would also contribute to an increase in cost since metal is more expensive than plastic.

Making Connections Beyond

Perhaps my greatest takeaway from this project is how much one can learn by taking apart a product and examining its design in detail. This got me thinking about the benefits that something like this could have in developing countries, where there is little technical background or knowledge.

Encouraging people in those communities to take apart and try to truly understand the technology in their lives would be a great way to empower them. It could illustrate to them that even seemingly complex technology was once developed by someone, somewhere, and now they can understand why the designer had done what they did. Taking apart technology can also encourage innovation.

By understanding how each parts function, people could think of ways to improve upon these parts and in turn improve the overall effectiveness of the overall product. Furthermore, they can learn to find alternative uses for parts in an old or no longer usable product. There exists a movement in encouraging children to take apart technology, and I believe the same type of curiosity can be fostered in people in developing countries. It would promote the idea of knowability, and help people learn that technology is not just a black box. Allowing them to understand technology would be a great tool to foster confidence, empowerment, and innovation.

Watson-Webb Sustainability Series: Hand-washing the Smart Way

Remember the hand-washing times data we obtained earlier? Here it is again:

Table 1. Hand-washing times.

At first glance, it may look like that I don’t wash my hands thoroughly. Allow me to explain. Alisha and Dasha, as well as most people I have observed in my experience, turn on the sink first and wet their hands before getting soap. While they lather their hands with soap, they leave the water running. This increases the amount of time that water is left flowing and the amount of water used for hand washing.

Figure A. Me washing my hands! Excuse the container of Greek yogurt. You gotta have a mid-project snack.

Figure B. Dasha washing her hands!

Figure C. Alisha washing her hands!

What I do is get soap first, without turning on the sink. I lather (very thoroughly. My elementary school health classes taught me well) without leaving any water running in the background. Therefore, my measured time is shorter because it only takes into account the time it takes for me to rinse my hands off of the soap. This technique saves a significant amount of water. Comparing my water use for hand washing to that of the average of Dasha and Alisha’s I save almost 60% of water by turning the water off while I lather my hands with soap.

Calculation:

Assuming flow rate to be constant, I will use the time it took for us to wash our hands on the 5th floor to calculate percentage difference:

4 s / [(8 s -6 s)(0.5)] * 100 = 57.14%

I believe that it my hand washing technique could use propagating. I have put up a sign on the bathroom door promoting this technique. If people do not like to use soap on dry hands, I suggest adding a little bit of water to liquid soap. This way, the soap lathers more easily, and you still manage to save water but not leaving the tap running.

#analysis #ww sustainability series

Watson-Webb Sustainability Series: Lights Off, Please

Dasha researched the amount of time it takes for the lights to shut off in the hallways, showers, and rooms. I found that the amount of time it takes for the lights in my room to turn off is 100 minutes after little movement (I used my closet door to somewhat block my sensor and hid in my corner desk behind my bed. Actually sitting that still and watching the time for 100 minutes might be torturous.)

Dasha assumed 28 watts used for each fluorescent light and calculated that if a student leaves the room without turning off the lights, 1.68 x 105 Joules of energy will be wasted. However, this acts as a ceiling on the amount of energy wasted. If a student left the room without turning off the lights, and returned prior to 100 minutes later, then the energy wasted from the lights would be reduced. However, if a student forgets to turn off the lights and does not return for say, a whole day, then the maximum amount wasted is still the 1.68 x 105 Joules ceiling.

100 minute is also not too short of a time as to cause lots of frustration among students. For example, the sensors can often fail to detect my presence in my room due to the layout of the furniture in my room. But even so, having to get up and move after 100 minute or so is not too irritating.

She also analyzed the bathroom sensors and found them to be inefficient. She noted that the sensors only respond to motion in the sink area, so often people in the shower are left in darkness after about 10 minutes.

I think an point to keep in mind is that once the lights turn off, people start to feel the need to hurry up and wrap up their showers. This may have been a measure that the designer took to save water.

The lights in the hallways, however, can be overly sensitive. The lights down the hall respond to motion near the elevator area, even if those people were not planning to walk down said hall. A method of improvement found was to decrease the sensitivity of the sensors, so that the lights do not light up unnecessarily. However, keeping the lights turned off unless people are present is a good way to keep down energy consumption. All in all, we found the use of motion sensors and automatic shut-off lights to be a worthwhile way to save energy from lights, however, improvements could be made with regard to sensor sensitivity in the hallways.

#analysis

Watson-Webb Sustainability Series: Watson-Webbites (NOT) Wasting Plastic

There is a water bottle filling machine downstairs that provides filtered water for filling up reusable bottles. It has a counter that keeps track of “number of bottles saved.” To analyze this claim as well as what it means for the environment. To gather data, we measured the amount of water that the machine takes to mean “one bottle” using a Nalgene bottle with millimeter markings. We took an average of 3 trials and found that the machine takes approximately 16 oz, or 0.5 L, as one bottle.

Alisha did analyzed number of plastic bottles saved according to the counter on the machine (16000 bottles) as well as the resources involved in the manufacturing of those bottles, and found the following savings in energy and resources in Watson Webb since the beginning of the school year:

These are significant environmental savings in Watson-Webb due to the installation of a water bottle filter to decrease the use of water bottles.

However, the water counter number is found to be more of a marketing tool for the machine rather than an accurate representation of the amount of environmental resources saved through its use.

For one, many people in the dorm use their own water filter pitchers, or drink from tap or water fountains. They would not purchase plastic bottles even if the machine did not exist. Also, the water from the water bottle filler may have been used for non-drinking purposes, for which plastic water bottles would not have been used as a substitute.

The amount of savings also did not take into account the cost of manufacturing reusable bottles and cleaning them.

From personal experience, the water bottle filler is valued for its convenience as a means for students to get clean, filtered drinking water. This efficacy exists regardless of how accurate the environmental impact counter is. Something like that might be more meaningful in a high-traffic, tourist area where people who want water have only the two main choices of purchasing plastic bottled water, or filling up a reusable bottle using the machine, rather than in our dorm, where students can obtain water in comparably environmentally friendly ways.

#analysis

Watson-Webb Sustainability Series: Watson-Webbites Flow Low

Low-flow sinks

Something that students tend to complain about is the low water pressure in the dorms. This is particularly noticeable in the sinks, especially in comparing them to the sinks on the first floor. While it might follow logically that sinks with a lower flow would save more water, we need to take into account of the fact that it doesn’t take as long to wash your hands when there is a higher water pressure and water flow. This means people may be using the low-flow sinks for a longer amount of time. Therefore, I wondered how much water the low-flow sinks on our floor actually do save.

Gathering Data

Water Flow

We measured water flow by running the sink for 10 seconds and measuring the amount of water with a Nalgene bottle with millimeter markings.

Figure A: Reading the water flow volume after 10 seconds on the 5th floor.

We did this for each of the four sinks on the fifth floor, and numbered the sinks in numerical order from right to left. We attempted to repeat the experiment on the two sinks on the first floor, but the water pressure was so high that water would begin to squirt out of the bottle before 10 seconds was up. Therefore, we adopted the use of a large tub to hold the water, for subsequent measurement with the Nalgene bottle.

Furthermore, the amount of water flow was so large for 10 seconds that we decided to decrease the time interval to 5 seconds, for sake of minimizing the environmental impact of our experiment and the convenience of measuring by a Nalgene bottle with limited capacity.

Figure B: Measuring large amounts of water flow by using a large tub to hold water, then measuring specific amount using smaller water bottles.

However, since 5 seconds is a shorter interval, which may magnify human error in measurement due to timing and turning the sink on and off. To compensate, we did two trials for these two sinks.

The data are found as follows:

Calculations: Unit water flow (mL/s) = Measured Water Flow (mL) / Time (s)

Hand-washing Times

We also gathered data on one of the most common water-use activities in the dorm: hand-washing. Each member of our power group washed their hands as they normally do, and measured the amount of time it takes for them to do so. We each did this once on the fifth floor, to find the amount of time it takes to wash hands in a low-flow sink, and did so again on the first floor sinks to gather data in a high-flow sink setting.

Then, we calculated the amount of water that each member used based on the unit water flow calculations we obtained from measuring sink flow.

Calculation: Water Used (mL) = Time(s) * Unit water flow (mL/s)

(Rounded to 2 significant figures)

Analysis

Water Flow

Based on the water flow data and calculations, I found that the flow rate for the 5th floor sinks is 141 ml/s, and that of the 1st floor sink is 846 ml/s. Conversions to the standard water flow rate unit of gallons per minute (gpm) can be found in the table below.

Calculation: Water flow (gpm) = Water flow (mL/s) *(1 gallon / 3 785.41178 ml) * (60s / 1 min)

I found out that the water flow of the high pressure sinks on the first floor is over 530% that of the fifth floor.

(2.3 gpm / 0.4 gpm) * 100 = 530%.

This is a significant difference in the amount of water that low-flow sinks can save.

To assess the relative water efficiency of the 5th floor sinks, I researched existing specifications for efficient bathroom faucets and found some through WaterSense. WaterSense is a partnership program sponsored by EPA with the goal of protecting the future of the U.S. water supply. They offer certification and labels for manufactures whose products meet EPA standards for water efficiency. The specification for bathroom sinks issued by the EPA is less than 1.5 gallons / minute. (WaterSense).

The low-flow sink water flow rates are 0.4 gallons per minute. This is significantly below the specification, which goes to show that these sinks are considered to be on the efficient end of water efficient sinks. In fact, the flow rate of the 5th floor sinks is 73% less than the EPA specifications.

Calculation: (1.5 gallons / minute - 0.4 gallons/ minute) / (1.5 gallons / minute) * 100 = 73%

WaterSense also specified that the Department of Energy uses 2.2 gallons per minute as the maximum flow rate standard for all faucets, as of 1992. Interestingly, the flow rate that we measured on the 1st floor sinks, 2.3 gpm, seems to exceed that amount by 0.1 gpm. This could easily be attributed to human error, however, this demonstrates that the water flow rate on the first floor is placed just at the maximum flow rate allowed for faucets.

This might be because the housekeeping staff fill up their water from the first floor, and that a high flow rate is required for increased efficiency of their work, as they don’t have to wait as long when filling up water for cleaning purposes.

In addition, the first floor bathroom is used most often by visitors of the building—friends, parents, workers, inspectors, and visitors of the university. It is evidently important that these visitors get a good impression for the dorm. Low water pressure may be frustrating to them or a sign of poor design. Infrequent visitors of the building tend to use the bathrooms on the first floor, and the designers wanted the visitors to have an optimal experience in the building, even if it means some compromises in the overall sustainability.

Savings in Water

Based on the hand-washing times table, one can easily tell that the water used for hand washing on the first floor is significantly greater than the water used for hand washing on the third floor—over 3 times as much, in fact.

Everyone’s hand washing habits can differ significantly, so I investigated the amount of water that I would save by using low-flow sinks rather than the high-flow sinks.

I counted the number of times that I washed my hands in the past 24 hours in the dorm, and it amounted to 6 times.

I went on to determine the amount of water I would save by using only high-flow rates (like those on the first floor) and only sinks with low-flow rates (like those on the 5th floor.)

Water Use for Low-Flow Sinks

(7 times) (225.25 mL) = 1 576.75 mL

Water Use for High-Flow Sinks

(7times) (564 mL ) = 3 948 mL

Difference = 2 371.25 mL = 2.4 Liters

Low water flow sinks save 2.37 liters of water, per person, per day, just for the activity of hand-washing. This data is likely to be amplified for other people, because I am a water hippie and do not use very much water when I wash my hands (read on for more details about this.)

This is a significant amount of water saved. In fact, 2 liters of water is enough for a healthy human’s consumption per day (LennTech).

How much water do low-flow sinks is save in Watson Webb?

I wondered how much water Watson Webb saves in total from using low-flow water faucets, as opposed to the high-flow water faucets on the first floor.

Water wiki tells me the following information about average minutes of faucet use per person per day.

(Source: http://sogweb.sog.unc.edu/Water/index.php/Household_Water_Efficiency:_Faucets)

Note: The faucet use here includes water used for dish washing. Although the faucets are in a bathroom, they are the only sinks on our floors and residents do their dishes in these bathrooms using these sinks. Therefore, I believe it is an appropriate piece of data to be used to get a rough estimate water use in Watson Webb.

This data also reflects the fact that even though conserving faucet flow has a lower flow rate, people can tend to take longer time to do the same tasks than if they are using a high-flow sink.

Assuming the average minutes of faucet use per person per day on 5th floor to be that of the “conserving home,” and the same on the 1st floor faucet for the “non-conserving home,” I made the following calculations to determine amount of water saved.

Using low flow sinks

[(15+8.9)/2 ] min * 0.4 gallons / min = 4.8 gallons per person

4.8 gallons/ person * 200 people = 960 gallons in the dorm

Using High flow sinks

8.4 min * 2.3 gallons / min = 19 gallons per person

19 gallons / person * 200 people = 3800 gallons in the dorm

A comparison

(19 gallons – 4.8 gallons) / 19 gallons * 100 = 75%

3800 gallons – 960 gallons = 2840 gallons

Using low flow sinks saves 75% of water compared to using high-flow sinks on the 1st floor. A difference of 2840 gallons per day is saved in the Watson-Webb are saved by adopting the low-flow sinks!

#analysis #ww sustainability

Hopping On and On

Searching for Improvements

I researched foam grips and covering as part of the project. I was curious about whether the foam was the best material for hand grips. Since these hand grip coverings were not included in the original patent, I figured that the current designers had a say in choosing whatever type of material their hearts desired.I examined catalogs from grip manufacturers, particularly GripWorks, and explored other

options for handle grips. There was an wide selection of materials, shapes, and manufacturing processes. A selection of these materials can be found here.

Dip Molding vs. Injection Molding (For plastic grips)

I wanted to explore the viability of grip materials other than foam. One of the main

materials was plastic and vinyl, and there was an overwhelming selection of plastic and

vinyl grips. I decided to narrow down the grip types first by manufacturing process. The

most common processes for plastic and vinyl manufacturing are dip molding and injection

molding. Selection of the manufacturing process depends on the quantity of parts required,

the complexity, physical requirements, as well as the cost. I wanted to explore which

manufacturing process will produce the best quality at lowest cost.

Dip molding is usually preferred when tight tolerances aren’t necessary. The advantages

of dip molding includes low tooling cost, short lead times on cooling, and the ability to mold

complex hollow shapes. Dip molding of PVC materials also produce parts that are very weather resistant.

Injection molding can hold tolerances of +/- 0.001 depending on design and resin

selection. Injection molding also offers an almost infinite amount of material choices when

blends and additives are considered. This allows the greatest flexibility in attaining the right

combination of physical properties and lowest cost. Injection Molding is better for engineered parts that have significant loads and require tight tolerances. Dip Molding is better if physical requirements aren’t demanding and close tolerances aren’t required.

For the purpose of a pogo stick hand grip, great tolerances and significant loads are not

required. On the other hand, low cost is a major criteria for the product and savings in tooling costs would be a major contributor for the cost efficiency of the product. Although I found many grips with ribbed or honeycombed surfaces that are stylish and offer better grip, I decided to utilize grips manufactured through dip molding because of the need to cut costs. Thus, I decided to find grips manufactured through dip molding. This left mostly straight grips, without special contours or ribs.

Materials

Although the pogo sticks needs to be economical, I wanted to find the best quality for low

cost. The table below displays some different materials for grips and a brief description of the material.

In general, foams like NPVC are more comfortable than vinyl, because foams are less dense and provide more cushioning, while vinyl is more compact and provide less cushioning.

Pricing

The pricing of the materials were also researched. Specific pricing depends on the manufacturer as well as the order quantity. For comparison purposes, I found the price of quantities close to 20 grips and calculated the price per grip for the types of grips. These estimated prices will be high because factories would likely order many more grips at a time. However, packs of close to twenty are the most common quantity in which these grips are available. Thus, for comparison purposes, these small packages will be used to estimate relative prices.

These also will not be exact prices that the manufacture used because the manufacture sourced their parts from China. However, those prices are more difficult to obtain.

The prices can be seen in the following table:

The Decision

Foam grips and tubes, due to their low density and high cushioning ability, are decided to be

more comfortable compared to vinyl or plastic. Hand grips and tubes for the pogo stick have

purpose beyond simply covering the metal frame—the ought to provide comfort for the user.

Furthermore, since the pricing for NPVC foam is comparable to and relatively cheaper than

vinyl materials, I believe that NPVC foam is a fitting material for the pogo stick hand grips and frame covering. This material matches the design criteria of comfort as well as economy.

This process is perhaps similar to that which a manufacturer would go through in determining a what material to use for a certain part. This is a lot of thought going into foam grips, which may initially seem like such a minor part in the pogo stick. However, its importance cannot be neglected as that is where the jumper holds on to the pogo stick, and comfort in that area is very important.

If I were the manufacturer, I would also construct prototypes of the pogo stick with foam grips as well as plastic or rubber grips that are comparably priced and conduct consumer tests.

I believe another reason that foam grips were used is that foam tubing was definitely preferable to PVC on the frame part of the pogo stick where contact is made with the jumper's leg. It is critical for that part to be comfortable because the legs grip on to the frame, and a hard surface without foam cushioning is very uncomfortable. Therefore, the manufacturer may be able to get a higher discount by ordering foam tubes for the handle grips as well as the foam coverings, since that would allow them to order a larger quantity. This goes to show that individual parts of the pogo stick influence each other during the design process.

All in all, this specific design for the pogo stick may not have all that much room for improvement. The design has been around for decades, and the manufacturers for this design have likely thought of the beneficial features to add or detract from the pogo stick, based on practical, aesthetic, or economic considerations.

One way in which the pogo stick has improved is by scrapping this existing jumping mechanism. The flybar pogo stick is currently on the market for people who are involved in the sport of extreme pogoing. Instead of a single spring, this new model uses a series of thrusters as a piston. These pistons can be adjusted based on user preferences, and they allow for a greater jump height.

This goes to show that at some point, improvements for one specific design may be just about exhausted. In that case, further improvements would require thinking outside of the box, and beyond what already exists.

#reverse engineering #reflection

Reigniting the passion for education

Some members of my group arranged to meet with Ms. Beth Neville Evans today with the intention of finding more information about the computer literacy, and she was gracious enough to oblige. However, she seemed so excited when we pitched our original Sparking Curiosity idea to her. That was surprising to me, albeit pleasantly. For weeks now, I have been trying to thinking of a new idea that would couple education with a project that effected some tangible change to the San Mateo community. I had difficulty thinking of topics that we as students would be qualified to lead and teach about, and was really beating myself up about it. However, talking to Beth Neville and listening to her comments about our original proposal reminded me that education is an entirely worthwhile goal in itself. Our original vision was to instill scientific curiosity in the students and open up their mind. Even though it’s impact is not easily quantifiable or immediately tangible like technical solutions to an energy problem, it is still a tremendously important mission that would be beneficial to San Mateo.

Furthermore, another significant merit in this proposal is that it aims to address a deep, developmental issue—education—that would be a sustainable way to tackle challenges in San Mateo’s socioeconomic issues. Another benefit in this proposal is that is indeed small scale. Having seen the degree to which planned projects, such as the one about computer literacy, have changed after getting to the ground due to limitations in feasibility was testimony to the fact that we should not try to bite off more than we can chew. We may have big dreams and big ambitions, but we are still high school students. A major criteria in our proposal should be appropriate scale and fitting to our abilities.

I sincerely appreciated Beth Nevile’s input. Our proposal has officially gone in a circle in terms of concept, I suppose, although it’s definitely picked up valuable insights along the way.

For one, I believe the main flaw in our original proposal wasn’t the idea itself, but the skewed emphasis on scientific knowledge over curiosity and skill. It also had a lot to do with our report writing and presentation of our ideas and information.

However, now we’re at a much better place and I feel more confident about my original vision. That is comforting and encouraging to me because of passion I have for improving access and quality of education in the world.

There’s still a ton of work left to be done on PIDACS, but and I will keep working on it.

On a side note: Beth Neville is such an interesting and passionate person. She has all sorts of experiences and stories to tell, and her passion for San Mateo Ixtatan was inspiring to me. I sincerely appreciated this conversation with her. Going to San Mateo and executing this program proposal is something that I am genuinely interested in and will look into for next summer.

#pidacs #reflection

Visit Original Link

Filtros de Agua

Following up on my post about using children to spread awareness of water filters in developing communities, with the picture book as an example (click here to view post), here's another idea.

It's no secret that humans love music, or that songs are a fun and effective device to help people remember concepts. I think that a song would be a good idea for reminding children of the importance of filtering water before drinking. I authored a prototype for such a song that is easy to sing and gets the message across.

To the tune of the itsy bitsy spider.. sing along if you would like (to cover up my atrocious singing skills. But really. I am sincerely sorry.)

Filtros de agua nos protegemos

Vierta en agua sucio antes de beberlo

Se quita al agua de cosas pequenitas

Que de otra manera se puede enfermar.

Translation:

Water filters protect us,

Pour in dirty water before drinking

It gets rid of little things in the water

That otherwise can make you sick

I will have to consult some native Spanish speakers about making the wording of the song more natural. And maybe I should have recruited the Virginia Gentlemen to demonstrate the song. Point is, the song is very simple, very easy to remember. If children sing it often enough, they will hopefully remember the importance of filtering water before consumption, and use their childhood cuteness to encourage other people in their families and communities to filter their water.

#design

Wanted: A Better PIDACS Idea

With a second Reverse Engineering project going on, we’re still trying not to lose sight of the PIDACS revisions that my previous group is undertaking. We are having trouble finding a balance between scientific education and technical training. We understood that point that scientific theory might not have an immediate, practical education, but I didn’t feel satisfied with technical training because that means teaching someone to complete a task over and over again. The whole point behind our original proposal was to spark curiosity, teach them problem-solving skills, and give them confidence in their ability to solve problems in their own community.

I got to a point where my thoughts were going too much in circles and I decided to seek some outside advice. I met with Professor Elzey and told him about my conflict. He said that he agreed with the idea of teaching students principles, but emphasized the need to do so through hands-on activities that can be linked to something that students can do to benefit their community. An example he gave was showing students how to fix engines in a tractor, or a lesson in the science behind agricultural techniques that the community may have developed based on heuristics. I thought these were meaningful examples of combining education with a practical project, and afterwards tried to continue to develop these ideas.

I sincerely appreciated the conversation because I was at a point where I needed an outside opinion to get me out of the rut I was in. I had been overthinking and that stifled my creativity and innovation, but getting a fresh perspective was able to stimulate my thoughts again.

An issue we found with some of these ideas, however, was our own lack of qualification to teach it. None of our team members have experience in auto mechanics, and we’ll probably be as lost as they are. Same goes with agriculture. Honestly, the Mateanos would have a lot more experience about it and would be much better at it.

So, we tried to think of something that we do have a certain level of expertise in.

Computers! We have lived with it nearly our entire lives and have extended experience working with the basic software as well as the internet.

We tried to develop the idea of computer literacy as a program for the San Mateo. We found out about a 2010 Jefferson Public Citizen team who had planned a computer literacy initiative for the community in India. We contacted them to find more information. One of the members, MG, told us that they had started out planning to do a computer literacy project focused on teaching computer skills to students & teachers in the area, which is similar to the idea that we are thinking of. Then, after talking more with the community partner, they realized they actually only needed teachers to instruct really complex programming skills- which the team members didn't know—in order to obtain better jobs. Therefore, the team changed their project to a social research and assessment on the gap between education and employment in the region. Another member of the team, JH, also told us that they found their project to be not feasible after speaking with their community partner. The aspect about teaching basic computer literacy skills was found to be superfluous, because there already existed state-run schools and centers that taught computer literacy at a higher level than what the team members were qualified to teach for.

This was helpful in giving us ideas about other factors to be considered in carrying out a computer literacy program, such as existing programs and the current skill level of the students. There aren’t state-run computer literacy centers in San Mateo, but the high school students expectedly already have basic computing skills.

Our team decided to meet with Ms. Beth Neville again to get more information about computer literacy. See next post for details.

#pidacs #reflection #context

Biologicalization in the 21st Century

Professor Rodemeyer came to speak to us during STS lecture about the field of biotechnology and its implications on technology. He gave an engaging explanation of what bioengineering entails and what it means for society, and also posed a lot of questions about the risks and concerns for the rapid advancements in this sector.

One reason is that biotechnology is different from other types of technology because it is irreversible. Biology has the ability to reproduce and evolve. Therefore, the consequences of biotechnology is difficult to predict but are very high. There are a series of questions facing society about biotechnology. For example, who owns and controls these technologies? Should a company be able to patent genetic sequences? Should a patient with a genetic disease have a right to own his or her gene sequences? Who gets to make the calls? The government? The voters? Market forces? Who's to say that the government knows what's best for people? Are we willing allow the general public to make decisions about such complex scientific and technical ideas? Can we leave something this influential to the whim of market force?

These questions intrigued me, but I've found that they're very difficult to answer. I have had my sights set on pursuing biomedical engineering for a long time because of my longstanding interest in the field, but I hadn't thought of the career possibilities in the policy side of BME until recently. That interests me because I often find myself thinking a lot about the ethics of biotechnology. While the engineering side of me is fascinated by all the incredible things you can do by manipulating biological material--synthetic cells, 3-D printers for constructing tissues, improved techniques for drug delivery and cancer therapy-- but the stickier side has to do with the ethics of those technologies and implications that they would have on society.

After lecture today, I spoke to Professor Rodemeyer after lecture for a bit inquiring of his opinions about my internal conflict (and therefore was late to ENGR1410 today... so sorry!). He made lots of interesting points but the agreed that these questions are tricky and difficult to answer. He did recommend for me to read "Our Posthuman Future" by Francis Fukuyama, which discusses the consequences of biotechnology. I immensely enjoyed Professor Rodemeyer's lecture and thinking about the questions he asked. Ethics about biotechnology is something I know I will continue to grapple with.

#career #reflection #sts

Not done with PIDACS yet...

The PIDACS project has been the most challenging project we had done. It was a valuable experience just grappling with the complexities and realities of engineering. We didn’t have enough information and had limited means of finding out more. The problem was so open-ended and it was difficult to pin down a single approach. We had to learn to deal with incomplete information and the uncertainty inherent in life. It was also a valuable experience in navigating group dynamics and exploring how to most efficiently work with other people.

My team received an 8.0 on the PIDACS project and I admit I was very disappointed initially. Our group put in a lot of effort in developing our idea and hashing out the ideas behind and details of our proposal. It was very different from the more technical proposals from other teams, many of which involved power generation.

However I do appreciate the opportunity for revision look forward to them. As I sit back and go through the logic in our first project, that were many ways that our original effort was lacking, both in the report writing and concept generation. For one, we were too ambitious with our goals. Mateano students have so little background in science that understanding scientific concepts would be difficult. Furthermore, this knowledge cannot necessarily be utilized by the students because they are perhaps too theoretical. Our original intent was that scientific education in the long term will allow the students to change their own town, but this would be a very long process.

So, after re-reading the report with fresher eyes and analyzing that comments and suggestions that Professor Elzey made, I came up with the following list of ways in which our project can be improved:

Increase coherence in the report

The original report was too much of a compilation of answers to the questions and tasks listed in the book, rather than a coherent entity on its own.

Information that the book asked for can be included in a different order and different ways, and taking headings directly out of the book will not always follow logically

An introduction and transitions to hold the parts together. Beginning with something like “Part I” is too blunt. This does not provide background information to someone who has not participated in the investigative process as part of our engineering class.

Be more thorough in including research information in the report

We neglected to include the information about other aspects of San Mateo’s infrastructural challenges in the report, under “investigating current affairs.” Although we had done general research about the economy, potable water, and public health, etc., but in the report we focused too much on only the information we later decided to use, namely electricity and education.

Including information about other aspects which we had research demonstrate the comprehensiveness of our research, and supplements our rationale for choosing the topics we did in the end.

A chart would be helpful in displaying our research in the various categories of challenges that San Mateo faces.

Make the transitions from the initial approach to post-Beth-Neville approach more clear

Our project took a significant change in direction after meeting with Beth Neville. While there was a distinct change in perspective and our approach, the distinction was not made clear in the report. The information we had received was also blurred with what we already knew

A flow chart would be beneficial in demonstrating how our thought process changed after meeting Beth Neville

Incorporate more charts and visuals

Problem statement-restatement, and relationship between inputs and outputs could would logically fit into charts

Be less constrained during brainstorming

Write down ideas even if they may seem unrealistic at first

Be more specific in the wording of the proposal

The meaning of “basic” scientific principles will mean different things to different people: “simple”, “easy to understand” vs. “fundamental”

Direct focus further towards hands-on projects

Find more projects that is directly applicable to the community

Ex. Examine fuse boxes in houses to teach them about circuits

Presents operating scientific principles, while also giving them basic comprehension of what to do if electricity goes out

Explanation of scientific theories such as electrons should be viewed more as a supplement hands-on projects

Increase focus on teaching students how to learn

Be thorough in analyzing the feasibility of the project

Add cost analysis to the report

This is a rather hefty list but hopefully my group can get to it soon! This re-evaluation is very necessary, I believe there is merit in our idea of “Sparking Curiosity” and getting Mateano students to develop a basic understanding of science. However, our idea of “basic” is different from what might be basic to those students, and it’s also different from what Professor Elzey understands as “basic.” He gave the advice of using the phrase “operating principles” to convey the idea that we want to teach just enough so that students can understand. This illustrates our relative ineffectiveness in communicating our ideas in the original report.

I spoke with some of my classmates asking for feedback and advice on our project, and some of them expressed the sentiment that education seemed like a very long-term method to solve the energy problem. I agree with that point, and I believe we need to make clearer and better support our claim that energy is not the most pressing problem in San Mateo.

I am very passionate about access to education and it’s personally important to me that we readjust our educational proposal to a more feasible and impactful one.

#pidacs #reflection

Agora Partnerships: "Human Potential + Capital = Impact" ... or is it?

I was flipping through my calendar and came across Ashoka Fellow Ben Powell’s presentation that I wanted to attend but couldn’t make. I had a few minutes so I decided to stalk him via the internet and came across Agora Partnerships, an organization he founded to foster social entrepreneurship in developing parts of the world.

(Pictured above: a screenshot of the Agora Partnerships website).

Agora’s mission is supporting startup companies whose products or services aim to propagate social change. Agora entrepreneurs include companies that construct sustainable housing for marginalized populations in remote areas, or design and distribute local jewelry and crafts internationally. Agora provides significant assistance in helping the native companies market their products and connect to international markets and investors. This is critical because forming such connections is a major challenge in most developing nations.

I identify with Agora’s vision of promoting socioeconomic development by empowering local people to create a better life for themselves by providing them necessary tools and social connections. As I was reading through the website, however, I was concerned with the methods with which Agora measures the impact of their entrepreneurs. Quetsol, for instance, is a company that provides solar-based lighting solutions for the poorest regions of Guatemala. According to the web page, their impact is measured by largely quantitative measures of number many systems are sold, number of people who have light, and number of megawatts produced. These criteria are able to measure how much profit that the Agora entrepreneur is generates to sustain their own community, but fall short in gauging the impact of their products on the people who purchase them. Although a certain number of systems are sold, I believe it is important to ask the questions of what people are doing with the extra hours of light –additional work or TV watching? The spread of indoor lighting in the western world had changed the dynamic of work and home, so what is social impact of indoor lighting on homes that have them? Do these areas really need the lighting systems? How much has their lighting situation actually improved? Are individual families able to easily maintain these systems?

Figure 1. A visual representation of the factors that need to be considered when evaluating the social impact of Agora entrepreneurs.

Agora has such great intentions and I believe that if they assess the impact of their entrepreneurs in a more comprehensive manner, they might be able to maximize the social change that they are able to effect, and in turn make the businesses more successful. The idea of measuring social impact of nonprofit organizations like Agora interests me. There are all many NGO projects with great intentions and abundant resources, but their projects fail in the long term because they fail to consider the social integration of their projects. So many of them would drop off a product in a community but do not analyze how they are used, whether they are used, and what kind of an effect it is having on the community.

I would like to partner up with Agora and help them assess the impacts of one of their entrepreneurs.

#agora partnerships #social entrepreneurship #context

Considerations of the Social Context

Engineers can tend to take a reductionist approach and zero in on just the technical aspects of a problem. However, taking a problem out of context is analogous to taking words out of context—it can be misdirected, misleading, or incorrect. Thus, a purely technical and out of context problem statement tends to lead to a misdirected search for solutions. The reductionist approach also causes the design team lose sight of the original motivation and limits their ability to deal with the complexity of the real problem. Then, the final solution is likely to be ineffective in addressing the original problem.

Mr. Cogill initially presented us with the problem of constructing a hydroelectric power plant. That is a prime example of taking a reductionist approach. A hydroelectric power plant are a great idea but would it be feasible in the environment of San Mateo? Why do Mateanos need it? What is their current electricity situation and more importantly, how do they perceive it? Ask questions it and teasing our answers is critical in helping us tease out the social context and develop a way of tackling the problem in a more appropriate way.

Turns out, asking those questions led our teams away from the hydroelectric power plant. Knowing the social context completely changed our approach because the narrowing the problem to such a technical one took away the significance of Mr. Cogill’s original motivation, which is to improve the quality of life in San Mateo. However, in knowing the context, the teams in our class had a better understanding of the root causes of in the myriad of challenges that San Mateo faces and developed creative methods of dealing with them. Some teams came up with other methods of providing energy and others tackled education as a way to contribute to the long term socioeconomic development of San Mateo.

All in all, I believe these solutions were more comprehensive and effective than developing a hydroelectric power plant, at least in the context of San Mateos’s society. Knowing the social context allowed us to tackle deeper problems.

#context #pidacs #reflection

Children as the vehicle for spreading social change

An UVAGI project that I was looking into was one about potable water education in the Tzununa region. There will be existing instructors that already have developed a curriculum for water-education, and that the GI team will be assisting the instructor in teaching the information.

Here’s an idea that I have: I know that targeting the children can be an interesting and effective strategy for spreading ideas throughout a community, because they are the ones more likely to get excited about new ideas and tell their parents all about it. In fact, this strategy was utilized by the seat belt safety campaign in the 1980’s. Seatbelt usage had been hovering over 10% for a long time, when a campaign to educate children about seatbelt safety finally was implemented. The campaign aimed to teach children that seat belts save lives. By convincing them of the importance of wearing seat belts, the campaign encourages children to act as a reminder and encouragement for their parents to wear their seatbelts when they drive. Parents then would likely feel obligated to set a good example for their children and start to develop the habit of wearing seatbelts.

I believe this strategy would be effective on educating communities about the importance of using water filters.

If children can understand the importance of water filters in preventing health problems and saving the lives of their loved ones, they would be very active and vocal in promoting their use in their families and communities.

I had the idea of using a children’s book explaining germ theory and illustrating how water filters work to reduce the turbidity of water. Picture this: the wicked coliform in the water scheming to attack the fair young Maria Jimena who is always doing good deeds around the village. He plans for his team to get into her body through the water that she drinks every day. But not so fast! The strong, mighty Senor Arena el Laceador from a biosand water filter thwarts the plan of the evil coliform.

And scene!

I sketched up an example page in the picture book, then scanned it and colored it using Photoshop (artistic consultation courtesy of hall mate and future roomie Ms. Katy Hutto). This panel illustrates the concept that microorganisms, such as coliform sticks to sand particles (Senor Arena el Laceador / Mr. Sand Man, the Lasso-er), so it does not get to the drinkable water. Here, a heroic sand particle is trapping the evil, scheming coliform, who exclaims "Oh goodness! The lasso-er destroyed my diabolical plan! How shall I escape?!"

These stories can be made colorful and appealing to children, and which will engage their attention as they learn about the importance of clean water. Pictures would be appealing to children, more so than words or books. I believe that putting special emphasis on teaching children about the importance of water safety would be a worthwhile way to try to increase the use of water filters in the communities in Tzununa, and I would love to make a picture book about it if I do have the opportunity to go on the Tzununa project.

#uvagi #context #design

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