Design and Fabrication of Engine Powered Two Rows Rice Transplanting Machine

1

DESIGN AND FABRICATION OF ENGINE

POWERED TWO ROWS RICE TRANSPLANTING

MACHINE

Group Members:

ABDULLAH AHMED (100663)

SOHAIB IMRAN (100696)

BE MECHANICAL (2010-2014)

Project Supervisor

Dr. Tahir Rasul

Foreign Professor

DEPARTMENT OF MECHANICAL AND AEROSPACE

ENGINEERING

INSTITUTE OF AVIONICS AND AERONAUTICS

2

AIR UNIVERSITY, ISLAMABAD

DESIGN AND FABRICATIN OF ENGINE POWERED

TWO ROWS RICE TRANSPLANTING MACHINE

FINAL YEAR PROJECT REPORT

(2010-2014)

DEPARTMENT OF MECHANICAL AND AEROSPACE

ENGINEERING

3

DESIGN AND FABRICATIN OF ENGINE POWERED

TWO ROWS RICE TRANSPLANTING MACHINE

Submitted By:

ABDULLAH AHMED (100663)

SOHAIB IMRAN (100696)

Project Supervisor

____________________________ Dr. Tahir Rasul

Foreign faculty, IAA

Head of Department

____________________________

Dr. Basharat Ullah Malik

4

Acknowledgments

We express our humblest and profound gratitude to Allah Almighty Who has given

us the strength and direction to accomplish our purpose and guided us through every

think and thin.

This project would not have been possible without the guidance and the help of

several individuals who have in one way or the other contributed and extended their

valuable assistance in the preparation and completion of this project.

We would like to acknowledge the assistance of our supervisor Dr. Tahir Rasul for

guiding us throughout the designing process, for the support for our study and

research, for his patience, motivation and immense knowledge. We thank him for

his support and help and guidance with so much interest because of which we are

able to complete our final year project in time. He assisted in performing a

comprehensive literature review and the practical know how of things in the

fabrication phase. He helped us in converting our computer aided design into a

physical form. Moreover he is regularly checking our progress on the project.

We are also thankful to the Head of the Department of Mechanical and Aerospace

Engineering, Dr. Basharat Ullah Malik for his motivation, guidance and

suggestions.

Last but not the least; we would like to thank our parents and families for their

financial, motivational and never ending support in our study and in its success.

5

Abstract

This report provides a thorough description of the modeling and designing of an

Engine Powered Rice Transplanting Machine. It begins with research into the

problems of transplantation of rice in Pakistan and there solution, a brief study of

already existing machines and there working. Specified operating requirements and

working conditions stipulate the design, material and working principles

constraints. As part of the project, a schedule is laid out following industry

techniques. Brainstorming and decision matrices are utilized as well, conveying our

design process. A basic structure is designed using strength of materials, precision

in working and applied/allowable stress analysis, and material deflection.

Additional features are developed based on a more specific investigation of

customer requirements. This report not only covers the design, but also documents

its software analysis and simulation of the structure. Cost analysis and material

choices are relayed along with a complete set of engineering drawings for the

manufacture of the machine. We are thankful to our advisor and parents as without

their support and prayers it wouldnt have been possible.

6

List of Figures Figure 1: Map showing the rice growth in Pakistan ......................................................... 12

Figure 2: Random method for Rice planting ................................................................... 13

Figure 3: Straight row method for rice planting ............................................................... 13

Figure 4: Broadcasting method for rice planting .............................................................. 14

Figure 5:Drilling method for rice transplanting ................................................................ 14

Figure 6: Dibbling method for rice transplanting ............................................................. 15

Figure 7: Initial design of frame ....................................................................................... 28

Figure 8: Final design of frame ......................................................................................... 29

Figure 9: Highlighted slots for holding planting arm ....................................................... 30

Figure 10: Initial design of seedling displacement assembly ........................................... 30

Figure 11: Initial design of planting arm asembly ............................................................ 31

Figure 12: Initial design of seedlings tray ......................................................................... 31

Figure 13: Initial design of seedlings support ................................................................... 32

Figure 14: Final design of Planting assembly ................................................................... 33

Figure 15: CAD of planting arm ....................................................................................... 33

Figure 16: CAD of ground support ................................................................................... 34

Figure 17: back and front perspective view of Seedling box assembly ............................ 34

Figure 18: Seedling box .................................................................................................... 35

Figure 19: Finalized CAD of seedling box support .......................................................... 35

Figure 20: CAD of engine carrier ..................................................................................... 36

Figure 21: Initial design of wheel assembly ..................................................................... 37

Figure 22: Finalized design of wheel assembly ................................................................ 37

Figure 23: CAD of Floater ................................................................................................ 39

Figure 24: Planting arm assembly (arrow pointing to shaft) ............................................ 40

Figure 25: Velocity graph for Planting arm shaf .............................................................. 41

Figure 26: Stress analyses of frame .................................................................................. 42

Figure 27: Displacement analyses of frame ...................................................................... 43

Figure 28: Stress analyses of floater ................................................................................. 44

Figure 29: Displacement analyses on Floater ................................................................... 45

Figure 30: Stress analyses on wheel assembly ................................................................. 47

Figure 31: Displacement analyses on Wheel Assembly ................................................... 48

Figure 32: Stress analyses on rpm conversion shaft ......................................................... 49

Figure 33: Displacement analyses on rpm conversion shaft ............................................. 50

Figure 34: Stress analyses on planting assembly ground support .................................... 51

Figure 35: Displacement analyses on planting assembly ground support ....................... 52

Figure 36: Stress analyses on seedling box support .......................................................... 53

Figure 37: Displacement analyses on seedling box support ............................................. 54

Figure 38: Metal sheets for frame fabricaition.................................................................. 55

Figure 39: Gas cutting for frame ....................................................................................... 56

Figure 40: Drilling for frame ............................................................................................ 56

Figure 41: Eclectic spark welding for frame manufacturing ............................................ 57

Figure 42: Fabricated wooden floater ............................................................................... 57

Figure 43; Frame handle ................................................................................................... 58

7

Figure 44: Rings for fabricating wheels ............................................................................ 59

Figure 45: Bending of rings in to circle ............................................................................ 59

Figure 46: Welding of rings .............................................................................................. 60

Figure 47: Welding of rings together (top), Welding of bars with wheel rings for support

and strengthening (bottom) ............................................................................................... 61

Figure 48: Finished wheel set ........................................................................................... 61

Figure 49: Fabricated Planting assembly support frame ................................................... 62

Figure 50: Fabricated planting arm ................................................................................... 62

Figure 51: Fabricated Crank pair for planting arm assembly ........................................... 63

Figure 52: Fabrictated link for Planting arm assembly ..................................................... 63

Figure 53: Whole planting arm assembly ......................................................................... 64

Figure 54: Final assembly of wheel .................................................................................. 65

List of Tables Table 1: FYP time line..20

Table 2: Wheel assembly parts design details and specifications.40

Table 3: Floater engineering properties.46

Table 4: Wheel assembly engineering properties..48

Table 5: Speed control shaft engineering properties..51

Table 6: Planting arm assembly support engineering properties53

Table 7: Seedling box support engineering properties55

Table 8:Cost table for materials..67

8

List of Symbols Following are the representing terms which are used by us in the

calculations:

RTP = Rice transplanter

v = velocity

w = angular velocity

r = radius

T = number of teeth of sprocket

N = angular velocity

d = diameter

p = pitch of sprocket

= torque

P = power

J = polar moment of inertia

c = radius

= shear stress

= angle

t = time

9

Table of Contents

1.1 Acknowledgments ................................... Error! Bookmark not defined.

1.2 Abstract ................................................... Error! Bookmark not defined.

1.3 List of figures & Tables .......................... Error! Bookmark not defined.

1.4 List of Symbols ........................................................................................ 8

2 Chapter 1........................................................................................................ 12

Literature Review .............................................................................................. 12

1.1. Rice Crop ............................................................................................ 12

1.2. Rice Zones .......................................................................................... 12

1.3. Methods of Rice Planting[1] ................................................................ 13

1.3.1. Transplanting .................................................................................. 13

a. Random .................................................................................................. 13

b. Straight Row ........................................................................................... 13

1.3.2. Direct seeding ................................................................................. 14

a. Broadcasting ........................................................................................... 14

b. Drilling ................................................................................................... 14

c. Dibbling .................................................................................................. 15

3 Chapter 2........................................................................................................ 16

Understanding of project ................................................................................... 16

2.1. Advantages ............................................................................................. 16

2.2. Parts and functions ................................................................................. 17

4 Chapter 3........................................................................................................ 18

3.1. Timeline ................................................................................................. 18

3.2. Scope: ..................................................................................................... 18

3.3. Parts that will be bought and fabricated ................................................. 19

10

5 Chapter 5........................................................................................................ 21

Mathematical Modeling .................................................................................... 21

5.1. Power transmission mechanism design .............................................. 21

5.1.1. Engine ............................................................................................. 21

5.1.2. Velocity of machine ........................................................................ 21

5.1.3. Gear Box ......................................................................................... 21

5.1.4. Calculating diameter of shafts ........................................................ 23

5.2. Position analysis of planting mechanism ............................................ 24

6 Chapter 6........................................................................................................ 27

Computer Modeling .......................................................................................... 27

6.1. Design of frame: ................................................................................. 27

6.1.1. CAD Model of Frame: .................................................................... 27

6.2. Design of planting mechanism: ........... Error! Bookmark not defined.

6.2.1. Initial Design:................................... Error! Bookmark not defined.

6.2.2. Finalized Design: ............................. Error! Bookmark not defined.

6.3. Engine carrier: .................................................................................... 36

6.4. Wheel Assembly: ................................................................................ 36

6.4.1. Initial Design:.................................................................................. 36

6.4.2. Final Design: ................................................................................... 37

6.5. Bevel Gears addition: ......................................................................... 38

6.6. Floater: ................................................................................................ 39

Chapter 7 ............................................................................................................... 40

Analysis ............................................................................................................. 40

7.1. Motion analysis: ..................................................................................... 40

7.1.1. Bevel shaft: ...................................... Error! Bookmark not defined.

7.1.2. Planting arm dynamic: .................................................................... 40

7.1.3. Seedling box: ................................... Error! Bookmark not defined.

7.2. Stress analyses: ........................................ Error! Bookmark not defined.

7.2.1. Stress Analyses on Frame: ............... Error! Bookmark not defined.

Study results: .................................................. Error! Bookmark not defined.

Conclusion: ..................................................... Error! Bookmark not defined.

11

7.2.2. Stress Analyses on Engine Carrier: .. Error! Bookmark not defined.

Von Moses stress analyses: ............................ Error! Bookmark not defined.



7.2.3. Stress Analyses for Floater: ............. Error! Bookmark not defined.

6.1.1 Von Moses Stress Analyses: ............ Error! Bookmark not defined.



7.2.4. Stress Analyses on Wheel Shaft: ..... Error! Bookmark not defined.

Von Moses Stress analyses: ............................ Error! Bookmark not defined.

Figure 26.a ...................................................... Error! Bookmark not defined.



7.2.5. Stress analyses on bevel gear shaft: . Error! Bookmark not defined.




7.2.6. Stress analyses on planting assembly support: ..... Error! Bookmark

not defined.




7.2.7. Stress analyses on Seedling box assembly support: ................ Error!

Bookmark not defined.

Table 10 .......................................................... Error! Bookmark not defined.




12

CHAPTER 1

Literature Review

1.1. Rice Crop

Rice, an important food and cash crop, is the second staple food grain crop of

Pakistan after wheat and major source of foreign exchange earnings after cotton. It

is planted on an area of over 2.57 million ha (10% of the total cropped area) and

accounts for 17% of the total cereals produced annually. The annual production of

milled rice is about 6.5 million tons sharing 4.9% in agriculture sector and 1.1% in

GDP. Pakistan is famous for growing and exporting long grain aromatic Basmati

rice. The rice export increased manifold during the recent years and a record export

of 4.5 million tons of worth about US$ 1735.2 million was made during 2011-12

Pakistan ranks 13th in terms of rice production and 4th in rice export in the world.

1.2. Rice Zones

In Pakistan, rice is grown under diverse climatic and edaphic conditions. Basmati

predominates in traditional rice tracts of Punjab. In Swat at high altitude mountain

valleys, cold tolerant rice are grown. In the south of NWFP, Sindh and Baluchistan

IRRI type medium long grain heat tolerant tropical rice are grown (Figure 1).

Figure 1: Map showing the rice growth in Pakistan

13

1.3.Methods of Rice Planting [1]

There are two methods of planting rice:

1.3.1. Transplanting

In this method prepared seedlings are transplanted in the field.

Transplanting is done with following two methods:

a. Random

In the random method, seedlings are transplanted

without a definite distance or space between plants as you can

see in this frame.

Figure 2: Random method for Rice planting

a. Straight Row

The straight-row method follows a uniform spacing between

plants. The seedlings are transplanted in straight rows.

Figure 3: Straight row method for rice planting

14

1.3.2. Direct seeding

In this method, direct seeding of rice with dry land preparation is done.

Direct seeding is done with three methods:

a. Broadcasting

You can broadcast seeds uniformly on the field or in furrows in

a field. After broadcasting, cover the seeds using a spike-tooth

harrow.

Figure 4: Broadcasting method for rice planting

a. Drilling

Another technique is drilling seeds by hand on prepared furrows, or

by seed drillers.

Figure 5:Drilling method for rice transplanting

15

b. Dibbling

The third technique is dibbling, or hill planting. This is usually

practiced along mountain slopes or where plowing and harrowing

are difficult. Use a long wood or bamboo pole with a metal scoop

attached at the end for digging holes. Then drop the seeds into the

holes and cover them with soil.

Figure 6: Dibbling method for rice transplanting

The techniques discussed above are commonly used in Pakistan for

the production of rice. After the study of above techniques the need

of a more efficient rice production technique is felt which should be

efficient in cost and time, which can be fulfilled by the

implementation of a mechanical rice transplanter.

16

CHAPTER 2

Understanding of project

Mechanical Transplanting of Rice is the process of transplanting

specifically raised seedling of rice using an engine powered mechanical rice

transplanter at pre-determined and desired spacing.

A common rice transplanter comprises of:

A seedling tray like a shed roof on which rice seedlings are set.

Seedlings pickup forks that pick up a seedling from the seedling tray

and put the seedling into the earth.

Floaters and power transmission.

Machine transplanting using rice transplanters requires considerably less

time and labor than manual transplanting. It increases the approximate area

that 2 people can plant from 1acre/10hr to 1acre/3.7hr.

However, rice transplanters are considerably expensive for almost all Asian

small-hold farmers. Rice transplanters are popular in industrialized

countries where labor cost is high, for example in South Korea.

These were first developed in Japan in 1960s, whereas the earliest attempt

to mechanize rice transplanting dates back to late 19th century. In Japan,

development and spread of rice transplanters progressed rapidly during

1970s and 1980s.

2.1. Advantages

Efficient use of resources by saving on labor.

Cost saving (Rs 980 per acre).

Timely transplanting of seedlings of optimal age.

Ensures uniform spacing and optimum plant density (30 -35 hills/m2 with

4-6 seedlings/hills).

Less transplanting shock, uniform maturity of crop that facilitate timely

harvest and reduce harvest losses.

Reduces stress, drudgery and health risks of farm labors.

17

Generates employment and alternate sources of income for rural youth

through custom services on nursery raising and mechanical transplanting.

2.2. Parts and functions

The rice transplanter has two parts i.e. front and rear portions. The front

portion has diesel engine ranging from 3-4 HP depending on the make and

toothed iron wheel, the rear portion has floating board, nursery platform,

transplanting fingers with screws for adjusting plants/hill, depth setting

lever, chains for height adjustment of float board and pedal for float-lifting.

The floating board of the transplanter serves as a base and also helps in

movement of the machine over excess water in the field.

In general, rice transplanters transplant 2 rows in single pass with spacing

arrangements i.e. 30 cm x 12 cm that maintains 30 hills/ m, respectively.

Similarly, number of plants per hill can be varied (2-4 seedlings/ hill).

The labor requirement for transplanting using transplanter is 2 man-days

per acre and 1 transplanter can cover 2.2 acres a day.

18

CHAPTER 3

3.1. Timeline

Table 1

3.2. Scope: Our project requires to build a low cost rice transplanter which is suitable

to be used in the rice fields of Pakistan. In light of this, we will be covering

following areas in this project:

3.2.1. Initial Data and information gathering:

Initial information for rice transplanting machine will be

collected from online literature, Farmers who work in the rice fields

will also be contacted. Information obtained from the farmers will

be of prime importance as they will be asked what kind of machine

they want and what type of machine will be suitable for their fields.

3.2.2. Selecting Testing parameters:

After the essential information of machine is gathered from

literature review and surveying the farmers, testing parameters will

be selected that are essential for the machine to be successful and

usable in the practical environment.

19

3.2.3. Solid modeling:

Solid modeling of our machine will be carried out on

computer software package. Following are the main parts of the

machine that will be modeled.

Frame

Planting mechanism

Seed feeding tray

Padded wheels

Drive train

Floaters

3.2.4. Fabrication:

After the solid modeling has been finalized, the machine will

be fabricated with some parts manufactured according to

specifications and some bought from the market.

3.3. Parts that will be bought or fabricated Following are the parts that will be fabricated:

Frame:

Frame will be modeled and designed on PTC

CREO 2.0 software package.

Planting assembly

This assembly comprises of various parts that

include shafts, bars, linkages, chains and

sprockets. All parts will be modeled and designed

on CREO and only following parts will be fabricated,

remaining parts will be bought from the market:

a. Shafts

b. Linkage bars

Seed feeding box:

It is the box on which seedlings will be placed

and fed to the planting mechanism. These box are not

20

readily available in the market according to our

requirements so they will be manufactured.

Padded wheels:

These will be designed and fabricated by us

as they are not readily available in the market

according to our requirement.

Floaters:

Floaters will be fabricated by us according to

our requirement.

Single speed Gear assembly:

Gear assembly was made to order from the

market.

Following are the parts that will be bought readily from the

market:

Engine:

5 Hp engine will be purchased from the

market.

21

CHAPTER 4

Mathematical Modeling

4.1. Power transmission mechanism design

4.1.1. Engine

The output power of engine is 3.6KW with the net torque at 2500rpm is

10.3Nm

4.1.2. Velocity of machine

The normal human walking speed is 1m/s and in mud its speed

reduces that is taken as 0.75m/s, this speed is the speed on which machine will run

during its operation in the field.

The engine output rpm are 2500 when the max torque is delivered by it, and

the required velocity of machine is 0.75 m/s, so the relation is derived between the

engine output and machine speed, that is:

As v= r * w

v = 0.75 m/s

r is taken as: r = 0.15317 m

so 0.75 = 0.15317 * w

w = 0.75 / 0.15317

w = 48.5 rev/min

So w of wheel is 48.5 rpm

4.1.3. Gear Box

As rpm of wheels are known so a speed reduction mechanism is designed which is

chosen a gear box.

To design the compound gear train we have formula of the relation between teeth

numbers and revolution per minute of a gear.

=

22

In this formula N is the number of rpm gears and T is the number of teeth of gear.

Two conversion shafts are used for the purpose of speed reduction so the formula

becomes:

135

246=

6

1

T1 is for engine output shaft and gear box input sahft.

T2 and T3 are on first conversion shaft.

T4 and T5 are on second conversion shaft.

T6 and T7 are on third conversion shaft.

T8 is on wheel shaft

T1, T3 and T5 and T7 are assumed as 12 teeth because to reduce the speed input

gear should have low number of teeth then output gear.

We know the value:

N1 = 2500rpm

N8 = 48.5 rpm

Putting values in the formula

1 3 5 7

2 4 6 8=

8

1

The output teeth are assumed as equal in numbers i.e T2 = T4 = T6 = T

12 12 12 12

4=

48.5

2500

T = 32 teeth

Calculating diameter of gears

After evaluating the teeth of sprockets radius is also evaluated to use it in designing

phase and calculating force phase.

23

The formula for the diameter calculation of sprocket is

=

The teeth t1 = T1 = T2 = T3 = 12 and t2 = T2 = T4 = T6 = 32

Using the formula described above to fine out the diameter of all gears.

Pitch of teeth is 0.005meters

For t1: 0.005=

12

d1 = 0.0191 meters

for t2:

0.005=

32

d2 = 0.05 m

Transmission of Torque

The engine that is selected have maximum torque of 10.3 Nm at the 2500rpm and

this torque is transmitted to wheels and planting mechanism.

The formula of torque transmission between two gears is:

=

Calculating torque transmitted from engine to wheel shaft:

8 = 521.06 Nm

4.1.4. Calculating diameter of shafts

The radius of shafts are calculated by using bending moment

diagrams of each shaft.

The formula used for this purpose is:

24

=

J = /4

c is radius of shaft

all is the max allowable shear stress of mild steel = 115 MPa

max is calculated by using the force and bending moment diagrams on wheel

shaft.

24

=

23 =

Calculating diameter of wheel shaft:

23 =

1394.76

115 106

C = 0.0197 m

Diameter = 3.94 cm = 4cm

4.2. Position analysis of planting mechanism

As the planting mechanism is four bar so first of all linkage system is is

designed for the required motion of planting mechanism.

The linkages lengths are taken from the literature review which are then changed

to the required dimentions for our machine using grashof conditions to analyze the

proper motion of four bar mechanism. Which is as follow.

The lengths and known angles are:

a = 7cm = 0 degrees

b = 19.3cm = to be calculate

25

c = 12 cm = to be calculate

d = 17.9cm = 9 degrees

Applying the Grashoff conditions

The formula is:

S + L Q + P

S = length of shortest link

L = length of longest link

Q and P are lengths of remaining links

Putting lengths in above formula

7 + 19.3 17.4 + 12

26.3 29.4

The above equality is true thus the condition is satisfied which shows that the

shortest link will take full rotation and no toggle will occur.

Now to formulate the equation of relations between the input 2 and the output 3

and 4.

Equating the vector sum of all linkages in x-axis

+ =

= R = R cos + sin

Replacing the scalar and vector value of all four links using the above formula.

3 = 2tan1

24

2

A= cos 2 + 5sin 2 + 5cos 2 + 6 4

B = -2sin 2+ 24

C = cos 2 + 5sin 2 + 5cos 2 + 6 4

Now

26

4 = 2.3

2

5 = 2.3

2

6 =2 222

2

4 = 2tan1

24

2

A= cos 2 + 2sin 2 + 2cos 2 + 3 + 1

B = 2sin 2- 21

C = cos 2 + 2sin 2 + 2cos 2 3 4

Now

1 = 2.3

2

2 = 2.3

2

4 =2+ 22+ 2

2

The above formulation shows that with any input of 2 the values of 3 4 can

be evaluated.

27

CHAPTER 5

Computer Modeling

5.1. Design of frame:

Frame of the machine is the part which will hold all the components of RTP

machine. These components include:

1. Seedlings picking assembly

2. Seedlings planting assembly

3. Tray Assembly

4. Wheel Assembly

5. Engine and engine carrier

6. Floater

7. Handle

8. Conversion shafts with sprockets

5.1.1. CAD Model of Frame:

Initial Design:

Material of frame: Mild Steel

Length of frame: 160 cm

Width of frame: 50 cm

28

Figure 7: Initial design of frame

1. Frame

2. Handle

3. 2x holes for padded wheel shaft, 1 on each side

4. 2x holes for conversion shaft_2, 1 on each side

5. 2x holes for conversion shaft_1, 1 on each side

6. 8x holes for engine carrier, 4 on each sides

7. 4x holes for holding floater, 2 on each sides

8. 2x holes for holding seedling tray support, 1 on each side

2

1

3 4

5

6

7

8

29

Finalized Design:

Figure 8: Final design of frame

Following were the changes that were made later on and was finalized to be

fabricated:

1. Change in length of the frame:

Length of the frame was reduced from 160 cm to 140 cm, due to following

reasons.

1. Removal of conversion shafts due to addition of gear box.

2. To reduce the mass of the machine.

2. Change in Width of the frame:

Width of the machine was changed from 50 cm to 65 cm due to following

reasons:

1. Requirement of bigger engine carrier due to installment of gear box and

clutch assembly to the machine

3. Slots for holding planting arm:

Two slots for holding planting arm were created in the rear end of

the frame that will hold the planting mechanism of the machine, as

shown in figure 8.

30

Figure 9: Highlighted slots for holding planting arm

6.1.Design of planting mechanism:

6.1.1. Initial Design:

The initial design that we picked for the planting mechanism of the machine

comprised of three steps process, which included; Picking of Seedlings from

seedling tray, passing the seedlings o the planting arms via picking assembly and

planting the seedlings in the rice field.

Seedlings picking assembly:

Seedling picking assembly comprises primarily of a simple

cam and follower mechanism. In which a trajectory upon which

gripper will move is used as a cam, while the gripper will function

as a follower. A set of forks will be used with the gripper to hold the

seedlings in place. Function of seedling picking assembly is to pick

the seedlings from the tray and pass them on to the planting arms of

the seedling planting assembly.

Figure 10: Initial design of seedling displacement assembly

31

Planting arm Assembly:

Planting arm assembly is the part of the machine that will plant seedlings in

to the rice field after picking it from the seedlings picking assembly. This assembly

comprises of closed loop four bar mechanism. As our machine is two row planting

machine so there are two planting arms that will plant the seedlings into the field.

Figure 11: Initial design of planting arm assembly

Seedling tray:

Seedlings tray is the part of

the machine that will hold the stack of

seedlings. Picking arm will then pick

the seedlings from the tray and then

will carry it to the planting arm to

plant them to the ground.

Figure 12: Initial design of seedlings tray

32

Seedling tray support:

It is the support that holds the seedling trays and seedling picking

mechanism.

Figure 13: Initial design of seedlings support

6.1.2. Finalized Design:

Planting assembly design was entirely changed from three step planting

method that included picking the seedlings from try, transferring them to the

planting arm via picking arm and planting into the soil via planting arm.

New design is a two-step process that includes picking the seedlings from

seedling box and planting them into the soil via planting arms. It removes the need

of having a picking arm in the whole mechanism.

The reasons for this design change are:

To avoid breakage of seedlings roots which in a three-step planting method

breaks away due to transferring the seedlings from picking to planting arm.

Reduction of weight and complexity of the machine while maintaining the

workability.

The above mentioned design changes necessitated the changes in following parts:

33

Planting arm assembly:

Figure 14: Final design of planting assembly

1. Change in Planting arm:

Change in the planting arms design and thus it was carried out accordingly.

The new planting arm design details are as under.

1x Set of planting arms

Material: Mild Steel

Max vertical length of

arms: 21 cm

Distance between arms:

22.2 cm

Crank hole dia: 1.5 cm

Connecting link hole dia: 1.5 cm

Figure 15: CAD of planting arm

34

2. Change in Planting mechanisms frame:

Design changes in planting mechanisms frame are as under:

1x Planting arm frame

Material: Mild steel

Frame thickness: 0.5

cm

Frame width: 18 cm

Max length: 30.6 cm

Figure 16: CAD of ground support

3. Changes in Seedling carrying assembly:

The seedlings carrying assembly was entirely changed from seedlings

carrying tray to seedlings boxes that are triangular at the bottom to allow the

passage of desired number of seedlings from the box openings.

Figure 17: back and front perspective view of Seedling box assembly

Following are the design specifications for this assembly.

2x Seedling box

Length: 35 cm

Width: 16 cm

Depth: 14.5 cm

35

Inclined angle: 65

2x holes for nuts of 5mm

diameter

Material: iron

Figure 18: Seedling box

1x seedling box assembly support:

4x holes, 2 seedling box for 5 mm dia nuts

Figure 19: Finalized CAD of seedling box support

36

5.2. Engine carrier:

Engine carrier is the part of the machine that will hold the engine in place.

Figure 20: CAD of engine carrier

Material: wood

Max length: 660 cm

Width: 37 cm

Height: 50 cm

5.3. Wheel Assembly:

5.3.1. Initial Design:

Initially the wheel assembly was designed to work only n the rice field with

protruding paddles on the periphery of wheel that will help the machine to move in

the muddy rice field. Two wheels are connected together with the help of shaft,

which have a sprocket on it, that takes power from engine via chain mechanism to

rotate the shaft.

37

Figure 21: Initial design of wheel assembly

5.3.2. Final Design:

Figure 22: Finalized design of wheel assembly

In the final design of the wheel assembly, following changes were made in

the wheel and shaft;

An outer rim was added at the ends of the paddles of the wheel to allow the

machine to move on a smooth surface.

Two sprockets were added instead of one for the purpose of transferring

engine motion to the conversion shaft ahead

38

Details of the design are as follows:

Part name and details Computer model

2x Padded wheels


Inner rim diameter: 30 cm,

Thickness: 2 cm

Outer rim diameter: 42 cm,

Thickness: 1 cm

Number of paddles on

each wheel: 13

2x sprockets:

Small sprocket:

o Material: Alloy

Steel

o No. of teeth: 57

o Pitch diameter:

272.3

o Pitch: 0.015 m

Large Sprocket

o Material: Alloy

Steel

o No. of teeth:

o Pitch diameter:

272.3

o Pitch: 0.015 m

1x Shaft


Shaft dia: 3 cm

Shaft length: 80 cm

Table 2

39

5.4. Floater:

Floater is the part of the machine which will help the machine to float

smoothly over the rice filed, as the rice field consists largely of muddy water. It will

help the machine to remain above the water level at all times.

Figure 23: CAD of Floater

1. 4x connecting column with frame

Material : Wood

Maximum Length: 144.6 cm

Width: 65 cm

Thickness: 2.4 cm

1

40

CHAPTER 6

Analysis

6.1.Motion analysis:

The above motion analyses of the bevel gear shaft shows that the shaft rotates with

the constant velocity of 602.5 deg/sec as desired.

6.1.1. Planting arm dynamic:

Figure 24: Planting arm assembly (arrow pointing to shaft)

41

Figure 25: Velocity graph for Planting arm shaft

With the above motion analyses of the planting arm shaft it is confirmed that the

shaft rotates with the desired velocity of 1240.6 deg/sec

The above motion analyses graph shows the to and fro motion of the seedling boxes

with the help of slider joints as the box moves from mean position to the two

extreme positions.

42

6.2. Stress analyses: The yield strength of low carbon steel is 28.2e+006 N/m

6.2.1. Stress Analyses on Frame:

Figure 26: Stress analyses of frame

Study results:

Minimum Stress: 2.53435 N/m2 Maximum Stress: 6.3178e+006 N/m2

Conclusion:

From the CAD results, it is concluded that this part will not fail under the given

stresses as the maximum stress are much lower than the yield strength of the part.

43

6.2.2. Displacement Analysis on frame:

Figure 27: Displacement analyses of frame

Study results:

Minimum Displacement: 0 mm Maximum Displacement: 0.0917051 mm

Conclusion:

From the CAD results, it is concluded that this part will not carry out any

significant deformations according to loading conditions applied.

44

6.2.3. Stress Analyses for Floater:

Model Reference Properties

Name: 1060 Alloy

Model type: Linear Elastic Isotropic

Default failure

criterion:

Max von Mises Stress

Yield strength: 2.75742e+007 N/m^2

Tensile strength: 6.89356e+007 N/m^2

Elastic modulus: 6.9e+010 N/m^2

Poisson's ratio: 0.33

Mass density: 2700 kg/m^3

Shear modulus: 2.7e+010 N/m^2

Thermal expansion

coefficient:

2.4e-005 /Kelvin

Table 3

Figure 28: Stress analyses of floater

Study results:

Minimum Stress: 6.54482e-008 N/m2 Maximum Stress: 100265 N/m2

45

Conclusion:



6.2.4. Displacement analyses on Floater:

Figure 29: Displacement analyses on Floater

Study results:


Conclusion:



46

6.2.5. Stress Analyses on Wheel Shaft:


Name: 1023 Carbon

Steel Sheet

(SS)

Model type: Linear

Elastic

Isotropic

Default failure criterion: Max von

Mises Stress

Yield strength: 2.82685e+008

N/m^2

Tensile strength: 4.25e+008

N/m^2

Elastic modulus: 2.05e+011

N/m^2



Shear modulus: 8e+010

N/m^2

Thermal expansion coefficient: 1.2e-005

/Kelvin

Table 4

47

Stress analyses:

Figure 30: Stress analyses on wheel assembly

Study results:

Minimum Stress: 1.47848e-008 N/m^2 Maximum Stress: 6.76768e+007 N/m^2

Conclusion:

From the CAD results, it is concluded that this part will not fail under the

given stresses as the maximum stress are much lower than the yield strength of the

part.

48

6.2.6. Displacement analyses on Wheel Assembly:

Figure 31: Displacement analyses on Wheel Assembly

Study results:


Conclusion:



6.2.7. Stress analyses on rpm conversion shaft:


Name: 1023 Carbon

Steel Sheet (SS)

Model type: Linear Elastic

Isotropic

Default failure criterion: Max von Mises

Stress


N/m^2

49



Poissons ratio: 0.29


Shear modulus: 8e+010 N/m^2

Thermal expansion

coefficient:

1.2e-005 /Kelvin

Table 5

Stress analyses:

Figure 32: Stress analyses on rpm conversion shaft

Study results:

Minimum Stress: 6260.85 N/m^2 Maximum Stress: 2.38672e+008 N/m^2

Conclusion:



50

6.2.8. Displacement analyses on rpm conversion shaft:

Figure 33: Displacement analyses on rpm conversion shaft

Study results:

Minimum Displacement: 3.51493e-007 mm Maximum Displacement: 32.229 mm

Conclusion:



6.2.9. Stress analyses on planting mechanism ground support:


Name: 1023 Carbon Steel

Sheet (SS)


Isotropic

Default failure

criterion:

Max von Mises Stress

Yield strength: 2.82685e+008 N/m^2


51


Poissons ratio: 0.29



Thermal expansion

coefficient:

1.2e-005 /Kelvin

Table 6

Stress analyses:

Figure 34: Stress analyses on planting assembly ground support

Study results:


Conclusion:



52

6.2.10. Displacement analyses on planting mechanism ground

support:

Figure 35: Displacement analyses on planting assembly ground support

Study results:


Conclusion:



6.2.11. Stress analyses on Seedling box assembly support:


Name: 1023 Carbon Steel

Sheet (SS)


Isotropic

Default failure

criterion:

Max von Mises

Stress


N/m^2



53




Thermal

expansion

coefficient:

1.2e-005 /Kelvin

Table 7

Stress analyses:

Figure 36: Stress analyses on seedling box support

Study results:


Conclusion:



54

6.2.12. Displacement analyses on seedling box support:

Figure 37: Displacement analyses on seedling box support

Study results:


Conclusion:



55

CHAPTER 7

Manufacturing

7.1.Frame

Frame is made by low carbon steel sheet of 2.7mm. Desired shape

of frame is obtained by using press and cutting machine. Sheets are then

drilled using bench drilling machine. Then parts of frame are weld to give

a proper structure to it.

Cutting and bending

Figure 38: Metal sheets for frame fabrication

56

Gas cutting

Figure 39: Gas cutting for frame

Drilling

Figure 40: Drilling for frame

57

Electric Spark welding

Figure 41: Eclectic spark welding for frame manufacturing

7.2.Floater and engine carrier

Floater is made of poplar wood. Saw cutting is done to get desired

shape and white glue and nails are used to join all parts of structure.

Figure 42: Fabricated wooden floater

7.3.Seedling box

Seedling boxes are made of iron. Hand tool is used to cut the

sheet which is the weld by electric welding.

58

7.4.Seedling box support

Seedling box support is made of square pipe of steel. the

thickness of sheet is 2.7mm. angle grinder is used to cut the pipe of

desired dimensions and electric welding is used to weld the parts.

7.5.Machine handle

Machine handle is made of iron circular pipe. Angle grinder

is used to cut the parts and then electric welding is done to weld the

parts together.

Figure 43; Frame handle

59

7.6.Wheels:

Bending, cutting and welding is used in fabricating the wheels.

Figure 44: Rings for fabricating wheels

Bending:

Figure 45: Bending of rings in to circle

60

Welding:

Figure 46: Welding of rings

61

Figure 47: Welding of rings together (top), Welding of bars with wheel rings for support and strengthening

(bottom)

Finished Wheel set:

Figure 48: Finished wheel set

62

7.7.Planting Arm Assembly

Method of sheet metal cutting, welding and drilling is used in fabricating

the whole planting arm assembly.

Figure 49: Fabricated Planting assembly support frame

Figure 50: Fabricated planting arm

63

Figure 51: Fabricated Crank pair for planting arm assembly

Figure 52: Fabrictated link for Planting arm assembly

64

Figure 53: Whole planting arm assembly

7.8.Final Assembly of machine:

65

Figure 54: Final assembly of machine

66

CHAPTER 8

Cost

Sr. No. Product Cost (Rs)

1 Engine 10000

2 Clutch 5500

3 Gear box 7000

4 Frame 1600

5 Seedling box 1000

6 Floater 2300

7 Handle 700

8 Wheels 4000

9 Planting mechanism 1000

10 Engine carrier 600

11 Sprockets 5000

12 Chain 1300

13 Machine Assembly 32000

TOTAL 783000

Table 8

67

CHAPTER 9

Visits

9.1.Daska

In Daska we first searched for already existing machines for rice

transplanting then studied there mechanisms and problems.

Then we searched all the market of sheet metal and sprockets and shafts,

we inquired different prices of process like cutting, welding of sheet and

manufacturing of sprockets.

9.2.Lahore

We went to Lahore to buy engine and clutch for machine, first we

surveyed Bilal Ganj market which is the biggest market for car parts. But

we didnt find our required parts their after doing a lot of survey. Then we

went to Branth road where we found a huge market of new, imported and

locally made engines. We found a shop name SHINGHAI HARDWARES

from where we brought an engine of 5 h.p and a clutch assembly which is

actually used in engine powered lawn mower machines.

9.3.Rawalpindi

In Rawalpindi we first visited National Agricultural Research Center to

know about the current work being done on research and planting methods

on Rice Transplanting. We met Senior Research Engineer at NARC who

gave us valuable information on the subject. He also showed us a Japanese

made rice transplanting machine which was modified by NARC to be

suitable to work on Pakistani soil. We gathered all the valuable stats and

info from this visit.

We needed sheet metals for the planting assembly and material for

fabricating wheels of the machine. For this purpose we visited City Saddar

Road, checked various sheet metal cutting shops and finally ordered the

required material from Shabbir Steels which specializes in cut to size job.

They made us the required material at very economical rates.

68

CHAPTER 10

Conclusion A rice transplanter is a machine that transplants the seedlings of rice in the

paddy field from seedling box through planting arm using power of engine. This

machine has vast application is Pakistan and Asia. The basic motivation of

selecting this project was to solve the problem of farmers in transplanting rice

seedlings by providing a facility of fast and economical transplantation. A basic

structure was designed using dynamic study, strength of materials, sprocket

chain mechanisms, applied and allowable stress analysis. We have used Creo

pro and Solidworks software applications for modeling, simulation and stress

analysis. Through farms and farm machinery institute visits we were able to

understand the problem and work done so far on this machine more deeply and

also the methods and techniques used to manufacture agriculture machinery.

Fabrication of parts was done using different tools e.g. press machine, grinder,

welding plant, lathe, shaper and gas cutter. Choice of material relayed upon the

strength required and material available. Cost analysis is done on the basis of

CAD model and material selection. Testing will be done in the season of rice

plantation.

Recommendation

Laser leveling of rice field is always recommended before the use of rice

transplanting machine.

There should be two persons all the times with the machine while it is

working in the field, one to operate the machine and other to place seedlings

in machine boxes.

The machine can be further improved by incorporating automated feedback

control systems and actuators to its planting assembly.

By incorporating a seat for worker on top of machine and in turn

incorporating steering to the machine.

Further recommendations will be given after testing of machine.

69

References

H.K.S. MADUSANKA, 2011, DESIGN AND DEVELOPMENT OF PADDY SEEDLING TRANSPLANTING MECHANISM

University of Peradeniya, Sri Lanka

Md. Syedul islam and Desa Ahmad, 18 May 1998, EFFECTS OF SEEDLING RAISING METHODS ON THE ECONOMIC

PERFORMANCE OF MANUAL OPERATED PADDY

TANSPLANTER ISSN:0128-7680, University Putra Malaysia

R.N. Pateriya and R.K. Datta, 2012, DESIGN MODIFICATIONS OF MAT TYPE RICE TRANSPLANTER, International Journal of Advanced Technology & Engineering Research (IJATER),

Volume 2, Issue 6.

W.P. ENANG, 2010, POWER TRAIN TECHNICAL DESIGN RICE TRANSPLANTER University of Bath.

Ghafoor, M.A. Ali, R.U. Rehman and A. Razzaq, June 2008, FACTOR RESPONSIBLE FOR POOR MECHANIZATION OF

RICE TRASNPLANNTING IN PAKISTAN PAKISTAN

JOURNAL OF SCINCE, Volume 60,Number 1-2.

Documents

Design and Fabrication of Engine Powered Two Rows Rice Transplanting Machine