Aaron Murenbeeld

Mohamad Ferdos Alam

Muhammad R. Arif

Hussain Alhelal

Kaveh Arfaei

Ahmad Al Adel

Mechanical Engineering 3E05

Group: MJ04

1

Agenda Introduction

Existing designs

Problems

Improvements

Final Design

Conclusion

Questions

2

Introduction Water flows through the hose

Flow causes the sprinkler arms to rotate

Resulting rotation drives a gearing system which in turn drives the sprinkler

The front wheel provides steering for the system

3

Competitor’s Designs Products by Nielson and John Deere

Cast iron body

Weight

Yellow ~ 9 kgs

Green ~ 7 kgs

Nylon gears

Wheel Designs

Wheelbase

Track length

Nielson (Yellow)

John Deere (Green)

4

Problems Low water pressure

i.e. Residential vs. Agricultural neighbourhood

Derailing Problem in sharp bends

A factor of wheelbase and track length

Angle of ascent

A factor of gear ratio and available system torque

Gear system

Weak nylon gears

5

Design Objectives Optimize the sprinkler system

Redesign of Sprinkler Arms

New Gear box for desired torque

Angle of ascent

Turning Radius: Length of the wheel base

6

Sprinkler Arm Redesign of Sprinkler Arms

Bend Angle (φ angle)

Optimum Bend Angle = 45 o

Water Projection Angle (α)

Optimum Angle = 10 to 16 o

Exit Nozzle Diameter

Optimum Diameter = 3 mm

Arm length

Optimum Length = 223 mm

7

Water Projection Radius, Torque and Flow Rate vs. Angle α

φ =40oφ =45o8

0

2

4

6

8

10

12

14

16

0 10 20 30 40

Ma

gn

itu

de

of

Ra

diu

s, T

orq

ue

, a

nd

Flo

w R

ate

Water Projection Angle, α (Degrees)

0

2

4

6

8

10

12

14

16

0 10 20 30 40

Ra

diu

s, T

orq

ue

, a

nd

Flo

w R

ate

Angle α (Degrees)Water Projection Radius (m)

Torque (Gain 10) (N·m)

Flow Rate (Gain 10) (L/s)

0

2

4

6

8

10

12

14

16

18

20

2.2 2.3 2.4 2.5 2.6 2.7 2.8 2.9 3 3.1 3.2

Ra

diu

s, T

orq

ue

, a

nd

Flo

w R

ate

Nozzel Diameter (mm)

Water Projection Radius, Torque and Flow Rate vs. Nozzel Diameter

Water Projection Radius (m)

Torque (Gain 10) (N·m)

Flow Rate (Gain 10) (L/s)

Nozzle Diameter

φ =45o

9

Arm Length

10

0

2

4

6

8

10

12

190 200 210 220 230 240 250 260

Ra

diu

s, T

orq

ue

, a

nd

Flo

w R

ate

Arm Length (mm)

Water Projection Radius, Torque and Flow Rate vs. Arm Length

Water Projection Radius (m)

Torque (Gain 10) (N·m)

Flow Rate (Gain 10) (L/s)

φ =45o

Design Options Redesign of the Sprinkler Arms

Alternate Designs

4 armed Sprinkler

3 armed Sprinkler

Curved armed Sprinkler

2 armed Sprinkler

11

Determine System Speed Water depth ~= 13 to 26mm Optimum Radius = 9m

12

Relate System Speed to Gear Ratio

0

0.2

0.4

0.6

0.8

1

1.2

400 600 800 1000 1200

Fo

rwa

rd V

elo

city

(m

/min

)

Gear Ratio (1:x)

Sprinkler speed vs gear ratio

Green System

New System

Gear ratio was chosen from desired system velocity

Two gear ratios were chosen that provide the following watering depths

26mm

13mm

13

Gearbox New gearbox for desired torque

Yellow System

Gear Ratio

High Gear 1:488

Low Gear 1:894

Nylon Gears

System failed as indicated

New and Improved

Gear Ratio

High Gear 1:783

Low Gear 1:1102

Nylon MDS14

Gear analysis New and Improved

Gear Ratio

High Gear 1:783

Low Gear 1:1102

Nylon MDS

System will fail at indicated gear

Gear efficiencies

One way gearing ratio

Gear shifting

15

Number of Teeth Width (mm)

Gears Old New Old New

Worm 1 1

A 43 53 6 16

B 16 16 8 14

C 24 22 4 13.5

D 36 43 4 13.5

E 44 44 4 14

F 16 16 8 15

G 44 44 8 15

H 16 16 18 25

I 44 44 15 25

Torque Analysis Torque in new system

is approximately 2 times higher than old system

16

Angle of Ascent Angle of Ascent

Yellow/Green comes to a stop at 22 degrees limited by torque

New Design comes to stop when it slips Limited by coefficient

of friction (ground and wheel)

Important that center of gravity does not sit past the rear axel, when on a slope. Not a problem for the new system, CG well ahead of rear axel.

μAngle of Slippage

1 45o

0.55 28.8o

0.3 16.7o

17

Wheel Design Wheel Design

Front Wheel

Rear Wheel

Spike Design

Parallel paths/Singular paths

Wheels are Nylon MDS

Spike Configuration

Yellow Green

18

Turning Radius Turning Radius: Length of the wheel base Wheel Base

Wheel Base , W = 230 mm (new)

Track length

Track length , L= 195.5 mm

Resultant Turning Radius = 1.17 m

Yellow System Wheel Base

Wheel Base , W = 350 mm

Track length

Track length , L= 205 mm

Resultant Turning Radius = 2.48 m

19

Body Design New Body Design

Lighter

Lower Center of gravity

Maintenance

Materials

Body : Nylon MDS

Block : Cast Iron

20

Body Design Three bodies tried

Yellow body (9kg)

Green body (7kg)

New Body (4.6kg)

Nielson (Yellow)

John Deere (Green)

Light Test Body21

Conclusion Low water pressure New sprinkler arms

Derailing Problem in sharp bends Smaller wheel base

Angle of ascent Torque increased

Gear system New gear ratio

Nylon MDS gears

22

Thank you, Questions?

23

24