NIRVAPANA Rice Sowing Device

California Institute of Technology

Sandra Fang

Chan­Hee Koh

Elijah Lee

Katie Taylor

St. Gregorios Institute of Technology and Sciences

Vijayakrishnan G.

Krishnanand Pai

ME105 Final Report

March 13, 2013

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Table of Contents

Problem Statement and Background ............................................................................................... 2

Mission Statement .......................................................................................................................... 2

Design Process .............................................................................................................................. 3

Preliminary Design ..................................................................................................................... 3

First Iteration ............................................................................................................................. 4

Second Iteration ......................................................................................................................... 4

Prototyping ................................................................................................................................ 5

Final Design ............................................................................................................................... 6

Manufacturing ............................................................................................................................... 9

Funding and Distribution ............................................................................................................... 9

Progress and Future Work .............................................................................................................. 9

Major Challenges ......................................................................................................................... 10

Design Challenges .................................................................................................................... 10

Logistic Challenges .................................................................................................................. 10

Schedule ...................................................................................................................................... 11

Conclusion ................................................................................................................................... 11

References ................................................................................................................................... 12

Appendix ..................................................................................................................................... 13

Team and performance analysis ................................................................................................ 13

Data and Surveys ...................................................................................................................... 13

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Problem Statement and Background This past summer, 10 Caltech students from the Product Design for the Developing World class

travelled to Kerala, India and spent 10 days with the students of St. GITS University touring local

industries, shops and sites to learn about problems that may have engineering solutions. One of the

industries visited dealt with rice farming, which is currently experiencing multiple problems in

efficiency and production. Kerala currently produces less than one-­fifth of its requirement and

imports 84% of the consumed food grain from neighboring states. This is in part due to the land

being sold for other purposes, and in part due to a labor shortage in manual labor professions.

Kerala is a state with a highly educated population with a literacy rate of 93.9% [2], and thus it is

moving away from manual labor professions.

The current method of rice sowing is problematic in that it wastes a lot of seeds. Presently, farmers

toss the seeds by hand. This results in only about half of the seeds germinating due to improper

spacing. The uneven spacing also forces a laborious transplantation process to take place. If the

seeds can be planted with the ideal spacing of about 6” between them, the farmers could skip the

tedious and time consuming transplantation step.

The financial loss due to this inefficient process is significant. Currently, it takes two farmers

between 45 - 60 minutes to sow one acre of seeds. Each farmer earns approximately 400 Rs. per acre;

however, the losses due to overseeding are 800 - 1000 Rs. per acre, and since Kerala has around

62500 acres of paddy fields, these numbers quickly add up to a serious problem. It is important to

note that there are other rice sowing devices being researched and on the market, but none of them

have proven effective in the climatic conditions of Kerala that typically produce wet and muddy rice

paddies.

In an attempt to address the problems caused by the labor shortage and the inefficiencies in the

current method of rice sowing, we have developed a mechanized device to help the farmers sow rice

uniformly and quickly. We aim to increase each individual farmer's productivity by cutting waste,

decreasing the time spent seeding each paddy and by cutting out the transplantation step with

uniform seed spacing. With our device, a farmer will spend less than half the time he currently

spends to sow an acre, and also minimize wasted seeds.

Mission Statement Our goal is to develop and market a mechanical device to help the farmers efficiently and uniformly to sow rice paddy seeds.

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Feasibility Studies Our sowing machine will help the paddy farmers to efficiently sow seeds manually (by pulling the

device through the field) with the required spacing in between them so that they can reduce the

losses suffered due to manual sowing and address labor scarcity, with a secondary focus of making

the task less difficult for the farmers. There are about 60,000 acres of paddy fields in Kuttanad itself.

So by using only about 30 to 35 kilograms of seeds, huge sums of money can be saved. Since we

sow the seeds with correct spacing, there is no need for transplanting. This again saves time, labor

and effort. A levelling plate will also be attached to the device so that proper levelling of the field

can also be achieved before sowing.

Design Process Preliminary Design

Figure 1: Preliminary Design with PVC pipe pontoons

The preliminary design from the previous term is shown above on the left. We had a significant

problem of using PVC tube as pontoon, which weighed nearly 5 kg itself. The total weight of the

device would be over 10 kg with 5 kg of seeds, so the pontoon would not be strong enough to

sustain the weight on the paddy field.

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First Iteration

Figure 2: Testing our design with pontoons at the Millikan Pond at Caltech

The first design iteration we made this term was to replace the PVC tube with a foam

swimming noodle for flotation. As shown above, we tested out the device and found that it

could support more than 5 kg of materials (using textbooks as weights), which is our goal for

the device to carry rice seeds.

Second Iteration

After receiving valuable feedback from some helpful researchers at the Agricultural Research Center,

we realized that the mobility for our device needed to be completely changed. Our pontoons were

useful for flooded paddies, but previous designs have had much more success with sleds and

specialized wheels with projections on its circumference for navigation in muddy regions. Thus, we

replaced our pontoons with a system of specialized wheels and sleds. The wheels are useful for

traversing muddy areas without getting stuck, while the sleds help keep the device stable in more

flooded areas.

We also increased the amount of trays from one to three. After the visit to the Research Center, we

noticed that much more efficiency could be achieved if we used 3 trays of seeds instead of one.

We decided to improve our mechanism for releasing seeds as well. Instead of using rubber bands (a

very typical early-prototyping material), we used a combination of pulleys and springs.

We have shown customers our second iteration and received feedback from them on the design.

The response from the farmers is attached in the Appendix. Out of the six farmers interviewed,

three were neither satisfied nor dissatisfied with our potential design; only one was dissatisfied, and

two were satisfied. The result can be attributed to the fact that we asked them for input about a

theoretical design which had not yet been completed, so many wanted to withhold their judgment

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until they had seen the actual prototype. As only one farmer was dissatisfied, we went ahead with

building the prototype.

Prototyping

At Caltech, we used the Machine Shop extensively and purchased materials and parts from Caltech’s

Central Shipping and Receiving Center, as well as from companies such as McMaster. Below are

pictures of the parts we have created.

Figure 3: Left: Molded seed tray funnels (with help from Alain Tsai from Art Center); Right-top: Specialized wheels with projections on the rim, laser cut Plexiglas; Right-bottom: Pulley system

At St. GITS, due to the inability access certain materials, we used bike wheels to substitute for the

specialized wheels with projections, as well as plastic trays and lined them with plastic cut with holes

to achieve the desired spacing. No functional pulley system was attempted; however, the design

showed that the seeds dropped very evenly when the dropping mechanism was deployed by hand

(see next section).

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Final Design

The final design comprises of a number of designs that were conceived in the previous term as well

as some key additions. The seeder with the slider has been expanded to match the scale with ~6”

spacing in between. We were able vacuum mold the trays with the funneling mechanism thanks to

Alain Tsai of Art Center. These trays would allow the seeds to drop into the holes via gravity. The

seeder has 9 holes with the appropriate spacing in each tray and 3 trays are placed side by side to

increase the surface area covered every time the seeds are planted. A pulley mechanism controls all

of the 3 sliders simultaneously so that the seeds are planted at the same time. This pulley mechanism

is operated via one handle, which when pulled aligns the slider holes to that of the top seeder. The

slider is returned to its resting state through springs.

We decided to use both wheels and sleds to compensate for their respective weaknesses. Wheels

would allow for the seeder to move across the field in more or less a straight line. However, the wet

conditions of the paddy would make the wheels sink into the mud rendering it useless. To combat

this, the sleds would support the weight of the seeder due to the higher surface area that it provides

and distributing the load of the seeder so that it would not sink.

Design changes were made to add a field leveler at the front of the seeder; however, this change was

made too late in the term to be added onto the final full scale prototype.

Figure 4: Final Design (St. GITS)

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Figure 7: Final Design (Caltech)

Figure 5: Close-up of tray with rice seeds and bike wheel.

Figure 6: Seed deposition mechanism - note the even spacing of deposited seeds

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The figure above shows the final prototype at Caltech. The strings are connected to a slider

connector where each connector attaches two sliders so they may move at the same time. The rope

is attached to the connectors and when the handle is pulled, the sliders are pulled, dropping the

seeds. Springs return the sliders to their normal misaligned positions. The two wooden sleds are

obscured by the seed trays.

Figure 8: CATIA model of final design

The figure above is a CAD model drawn in CATIA depicting how the eventual prototype is to be

constructed. The seed containers were purposely not drawn to scale to show every element of the

prototype.

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Manufacturing Manufacturing will be done by Raidco (Regional Agro Industrial Development Co-operative of

Kerala Ltd.). But they will only manufacture for us if their Managing Director is convinced of our

design. We hope that will not be a very difficult task if NABARD (National Bank for Urban and

Rural Development) approves our design. We are thinking of using mostly plastic to keep the weight

down and also because it will not be affected by the watery conditions of the paddy field. The

wheels, seed containers, and sliding plates will be made of plastic. The frame onto which the

containers and wheels are attached and the handle will be made of lightweight metal.

We have contacted an employee of Raidco. Once we have completed the prototype testing we will

arrange a meeting with their Managing Director. If we are not able to directly approach the

Managing Director then we can get the help of researchers at the Agricultural Research Centre, who

can introduce us to him (not on behalf of the Agricultural Research Centre though!).

Funding and Distribution We have gotten in touch with NABARD (National Bank for Urban and Rural Development)

through CHASS. In order to receive funding, we are required to submit a project report detailing

our design. NABARD will provide us with feedback, and, if our report is accepted, they will provide

us with funding. We will then contact Raidco and hopefully with our project proposal and

NABARD’s support, they will be able to manufacture the device for us. CHASS will distribute the

product to farmers.

While we have not determined the cost of the final design (which depends heavily on the type of

materials used), we hope that CHASS will be able to lend our device to farmers, who will pay a small

sum for renting it for a period of time. This will keep our product affordable and distributable as

farmers will not be limited by a price barrier to use our device. Also, this process makes sense as

farmers will only need the device once or twice a year.

Progress and Future Work Initially we developed a preliminary prototype and it was tested in a paddy field, but it was ultimately

not successful. From the feedback we gathered and from the information provided to us from The

Agricultural Research Centre we came up with a new design and the prototype (separate for India &

US) is almost complete, though both have not yet implemented a functional pulley system.

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We discussed our ideas with CHASS (Changanassery Social Service Society) & KVS (Kuttanadu

Vikasana Samithi). CHASS has shown interest in our product and assured us of their support until

the product reaches the market.

As mentioned in the section “Funding and Distribution”, currently we are preparing a project report

to submit to NABARD through CHASS. We will submit it as early as possible (within 4 weeks).

NABARD will most likely consider this project for the next fiscal year, which starts from April 1,

2013. After going through this project NABARD will provide feedback and we will need to refine

our report accordingly. If they find the project report acceptable, they will allocate to us the

necessary funds. CHASS will then distribute the finished product to farmers.

Major Challenges We had a few challenges in terms of designs and functionality, as well as some problems in

communications, logistics, and overly ambitious scheduling. Most of these were overcome, and for

those design challenges that we did not overcome, we will work on in the near future.

Design Challenges

Much of the design challenges dealt with finding the appropriate prototyping material. In India

especially, we did not have access to a machine shop similar to the one at Caltech, and thus it was

very hard to create or find certain parts, such as the special wheels with projections on the rim.

Luckily, we solved the problem in India by using bike wheels.

We will have to determine the appropriate materials for our prototype in the future as our current

materials are too weak to allow us to rigorously test the prototype in the proper rice paddy

environment.

The pulley system and is currently non-functional for both of the prototypes. Because the concept

of the pulley system is more complex, we did not have enough time this term to work out the forces

required to move the sliding plates, and as such, the system had too much friction for it to work

smoothly. We are pleased to note that in the US prototype, the springs attached to the sliding plate

properly keep the sliding plates in the misaligned holes position when no force is applied.

Logistic Challenges

This term, we faced several problems in receiving vital information on time as well as

communications issues, and, interestingly, a copyright/intellectual property rights issue.

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Our team had difficulty communicating with each other occasionally due to internet problems,

which was aggravated by the fact that we required transcontinental communication. We also had

several issues in meeting with directors as occasionally they would be out of town and unreachable.

Thus, we did not receive the vital information we needed to proceed with the prototypes, and this

set us back in the overall schedule.

Finally, we ran into the rather unusual problem of copyright issues. The Researchers at the

Agricultural Research Centre divulged more information than the head was comfortable with, and as

a result, our prototype became very similar to theirs. The head of the Centre worried about

intellectual property rights, and although we are sure we have it sorted out, the process of

communicating with them as well as with Professor Ken Pickar and Katja Luxem delayed our

prototype further.

Schedule We were extremely ambitious in the beginning, and we learned to scale back our ambitiousness and

be more realistic and account more time for unforeseen delays. This is reflected in the fact that we

changed our schedule three times. The chart for the most recent schedule (which was adopted on

2/4/13) is shown below. While prototyping took longer than we expected (even with the removal of

an entire iteration cycle and starting earlier than planned), we ultimately managed to finish our

prototype and analyze its functionality by the end of the term.

Figure 9: Schedule for Term (second starting from 2/4/13)

Conclusion We have learned many valuable lessons throughout this term working on the project. Most of all, it

was our great pleasure to participate in Team Nirvapana working together to help farmers in India,

who suffer from the labor shortage. The hope that we could possibly aid them by constructing

mechanical device to efficiently and uniformly sow rice seeds was our great motivation for the

project; furthermore, working diligently to find possible supporters and manufacturers in India was

an eye-opening experience to explore the business side of the project. The valuable feedback from

farmers and interviews with landowners were necessary and significant in developing our device, and

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we have learned the importance of evaluation and feedback in the manufacturing process. Regarding

prototype, we initially planned the second iteration for the final model, but only the first iteration

was done due to modifications and delay in communications. Research about the product and well-

planned design, as well as better scheduled meetings, are options encouraged to compensate for

these problems. We will also be more aware of potential “unforseen circumstances” that push our

schedule back, and make more time to solve these problems.

For the future work, thorough testing of prototypes and analysis of their performance are required.

We had a major issue with the pulley mechanism due to significant tension and friction associated

with the spring, string, and sliding plates, so adding bike braking mechanism may be one solution.

Despite having previous copyright problems, we have succeeded in receiving possible funding from

NABARD, and we are looking forward to submit our project report within 3 weeks. Needless to say,

maintaining contact with the farmers club will be important along with contacting RAIDCO for

manufacturing.

In conclusion, we had a solid start to the creation and distribution of our device. Although not every

member will continue working on the project, our team members Vijay and Krish will carry on the

project and update on necessary information with other team members. Detailed documentation in

the report will be valuable in gaining contacts in industry and developing our device.

References

[2]: Literacy rate data: http://www.mapsofindia.com/census2011/literacy-rate.html

Amalorpavanathan, Shri R. National Bank for Agriculture and Rural Development. NABARD,

2007. Web. 26 Oct. 2012. <http://www.nabard.org/introduction.asp>.

Biju, Shri K. Kutanad Package Towards Prosperity. CDIT, 2008. Web. 26 Oct.

2012. <http://www.kuttanadpackage.in>.

Styger, Erika. System of Rice Intensification. SRI Rice, 2012.

Web. 14 Oct. 2012. <http://sri.ciifad.cornell.edu/contactus/index.html>.

Thomas, Jayan J. Paddy Cultivation in Kerala. Tech.

Review of Agrarian Studies, n.d. Web. 31 Oct. 2012.

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Appendix Team Performance Analysis

This term Team Nirvapana experienced some periods of stall and frustration, as well as periods of

rapid progress. I think one of the problems we experienced was that so much of the work this term

either needed to be done or was more efficiently and effectively done in India. Thus Krish and Vijay

undertook the lion’s share of the work. Krish and Vijay did an excellent job throughout the term on

the ground in India meeting up with government officials, researchers, farmers - really engaging all

of the stakeholders.

We also got a bit frustrated and stressed over miscommunications, difficulties staying in contact,

and roadblocks - such as the aftermath of the interaction with the Agricultural Research Center. In

addition, the inability in getting in touch with stakeholders who were on leave resulted in delays and

major design changes that overall set our schedule back. However, this does not negate all of the

successes we achieved this term as a team.

Despite some down times, our team has displayed passion and commitment to the project, and were

impressively still able to complete two functional, 1-to-1 scale prototypes by the end of the term. If

we could do it again, we would work a bit harder on staying positive and in motion.

Data and Surveys

We talked to farmers, researchers, and a marketing student to get their opinions on our second

iteration design (see the table below). Some were satisfied with the design and gave us some

suggestions to make some small changes. Those who gave a neutral feedback really wanted to put

their hands on the prototype and test it to see how effective it was. The person who was dissatisfied

was a farmer who had used a cylindrical seeder developed by the Research Center. He feels that the

current method is enough as using the seeders requires more effort.

Figure 10: Customer feedback on Second Iteration Design