This document describes the design and fabrication of a prototype solar-powered automatic grass cutter robot. A group of students at Muhammad Nawaz Shareef University of Engineering and Technology designed the robot to reduce pollution and noise from fuel-powered lawn mowers. The robot uses solar panels to charge its batteries and power brushless DC motors and a microcontroller to cut grass automatically. The document outlines the components, programming, assembly, performance comparisons, applications and future recommendations for the solar grass cutter robot.

1. Design and Fabrication of Prototype Automatic Solar
Grass Cutter Robot for Trimming
Muhammad Nawaz Shareef University of Engineering and Technology,
Multan

2. 3D Model of Solar grass Cutter

3. Group Supervisor:
Engineer Sania Azam
Lecturer:
Department of Mechanical Engineering and Technology
Group Members:
Mubashir Shehzad 2017-BT-MECH-713
Muhammad Shahid 2017-BT-MECH-715
Khuram Shahzad 2017-BT-MECH-718
Ramiz Khuram 2017-BT-MECH-720
Group Number 04

4. Mubashir Shehzad 2017-BT-MECH-713

5. Contents
❑ Aims and Objectives
❑ Introduction
❑ Background
❑ Statement of Problem
❑ Literature Review
❑ Our Contribution
❑ Block Diagram
❑ Program Description
❑ Main Components of Solar Grass Cutter
❑ Assembling of 3D Model
❑ Results

6. Cont…
❑ Comparison between solar and IC engine cutter
❑ Advantages
❑ Applications
❑ Future Recommendation
❑ Cost of Component
❑ References

7. Aim and Objectives
Aims:
➢ It will relieve the consumers and reduce the pollution and noise.
➢ This design is meant to be an alternate green option to the popular and environmentally hazardous
fuel powered lawn mower.
➢ Our main aim in pollution control is attained through this.
➢ This project aims at developing a portable solar operated grass cutting device, as there is power
shortage.
Objectives:
➢ To develop a prototype that reduces end user work through the utilization of an easy-to-use.
➢ To extend the design of currently used field mowers.
➢ To cut the grass in which farmer take too much hard working so we can reduce all that.

8. Introduction
➢ Grass cutter machines have become very popular today. Most of the times, grass cutter
machines are used for soft grass furnishing.
➢ In a time where technology is merging with environmental awareness, consumers are
looking for ways to contribute to the relief.
➢ Herein, we are proposing a model of the automatic grass cutting machine powered through
solar energy, (renewable energy).
➢ Automatic grass cutting machine is a machine which is going to perform the grass cutting
operation on its own.
➢ This model reduces environment pollution(noise and emissions).

9. Cont……
➢ Our new design for an old and outdated habit will help both customer and the
environment.
➢ This project of a solar powered automatic grass cutter will relieve the
mankind from mowing their own lawns.
➢ Ultimately, the consumer will be doing more for the environment while doing
less work in their daily lives.
➢ The hope is to keep working on this project until a suitable design can be
implemented and then be ultimately placed on the mark.

10. Backgrounds
➢Automated lawn mowers have been made available to the general public for over 30 years
(Georges 1999, p.195). on the other hand, it has been limited mainly due to the current costs
of such devices.
➢There are numerous real-world benefits of having a machine that autonomously cuts grass.
➢It is a device that can fit into just about everyone's lifestyle and very useful to mow the grass
from their lawns.

11. Statement of Problem
➢ Nowadays, solar grass cutters are commonly found in everywhere all around the
world.
➢ Before the last 10 years everyone used the Non renewable(i.e. gas or oil powered)
energy based grass cutter.
➢ Because the use of non renewable energy, there are lot of problems forward to us.
➢ So that, they need an alternative way to encounter these problems that damaging
the Ozon layer.
➢ Concerning into this problem, we have found there is a high demand to a product
which solving this problem and make people easier to mow their lawns
➢ This product is the most batter for them which is saving in term of time and cost.

12. Literature Review
➢ R. Sivagurunathan:
▪ In his research paper “Design and fabrication of low cost portable lawn mower” in Feb, 2018.
▪ In this study, he designed and fabricated a hand-held operated machine for grass cutting by
using locally available material
▪ In his research the most important aspects such as durability, strength and light weight was
taken into design consideration for better performance.
➢Z. I. Rizman:
• In his research paper ” An improved controller for grass cutting application” that published in
January 2018.
• in this study, he improved controller of machine cutter capable to improve grass cutting process
become easier.
• The manoeuvre of the machine is controlled by radio frequency (RF) remotely.
• The RF signal is transferred by the remote control to the lawnmower via the antenna (joystick).

13. Literature Review
➢ A. P. Pralhad:
• In this research paper “Solar powered automatic grass cutter and pesticide spreading robot” that
was published in May, 2017.
• In this study, he designed and fabricated a solar powered automatic grass cutter and pesticide
spreading robot, mainly proposal of that project is to reduce man power and the usage of IC
engine based vehicles.
• Solar plate was used to provide the source of battery charging, this is an automated system for
grass cutting.
➢ Ms. Y.Rutuja A:
• In the research paper ” Automated solar grass cutter” that published in February, 2017.
• In this study, he described the problems facing by us in daily life that are like pollutions, cost of
fuels, power cut etc.
• we thought about the device, which can be performed its functions without causing any of these
problems.

14. Literature Review
➢ S. Mohyuddin:
• In his research paper ”Automatic solar grass cutter” published in May, 2016.
• In this study, analyzed that a normal grass cutter moving with IC engine will run based on the
energy from petrol.
• The major drawbacks of this technology are high running cost; create noise pollution and air
pollution.
• Also, an IC engine requires periodic maintenance such as changing the engine oil, mechanical
maintenance.
• It is an innovative technology of cutting grass without any pollution, solar grass cutters are
environmentally friendly.

15. Muhammad Shahid 2017-BT-MECH-715

16. Our Contribution
➢ Unskilled operations can operate easily and maintain the lawn very fine and uniform surface
guise.
➢ In this project we use microcontroller for controlling various operation of grass cutter.
➢ The battery can be charge by using power supply and solar panel.
➢ In case of any obstacles in the path it is sensed by using an Infrared Sensor.

17. Block Diagram

18. Program Description

19. Main Components of Solar Grass Cutter
➢ Solar plate
➢ L293D Motor Driver
➢ Dry cell battery for store energy
➢ BLDC motor ESC 1000 KV
➢ LIPO battery 2200mah
➢ Infrared Sensor
➢ TT gear motor
➢ Rubber wheels

20. Description
➢ Solar panel:
• Photovoltaic solar panels absorb sunlight as a source of
energy to generate direct current electricity.
• We use a 10W solar panel which purpose is to charge the
battery and drive the motors of wheels.
➢ L293D Motor Driver:
• It is advanced controller with more features. System control
is done by using controller 16f877.
• It is heart of the system it controls all operations.
• Controller requires +5v for working properly. it provides
18mA current.

21. Cont.……
➢ Dry cell battery for store energy:
• Solar cell do not store energy. It is necessary to store some
of the energy produced.
• We used battery to store electrical energy generated by
the solar panel.
• Battery is the 7V and 4000 mah.
➢ BLDC motor 1000 KV:
• There is a DC motor that is used for rotation of the cutter.
This motor is brushless DC motor.
• This Motor is Driven by the driver L293D.
• The speed of the motor is up-to 10,000 rpm.

22. Conti….
➢ Lipo Battery 2200 mah:
• This battery used to store energy for drive the BLDC motor that
is used in Cutter.
• The BLDC motor is high voltage 1000 KV, and we can’t drive it
through direct solar energy.
• The battery is the 9V and 2200mah.
➢ Infrared Sensor:
• Robot is interfaced with the IR sensor for obstacle
detection.
• On obstacle detection IR sensor monitors it.
• The microcontroller thus stop the grass cutter motors of
wheels to avoid any damage.

23. Conti….
➢ TT gear motor:
• Used for rotation of the wheels of the grass cutter machine.
• More Speed than the other 4 motors.
• Speed of this motor on 3 V about 100 rpm and on 6 V it’s about
200 rpm.
➢ Rubber wheels:
• Wheel diameter: 60 mm.
• Load capacity: 3 kg - 10 kg.
• Tread width: 25 mm.
• Solid rubber castors and thermoplastic.
• Rubber castors for floor surface preservation and low-noise
operation.

24. Khuram Shahzad 2017-BT-MECH-718

25. Assembling of Design

26. Cont…

27. Complete Assembly

28. Design Analysis:
The shearing force of most annual and perennial grasses found on most lawns is usually between 9.2N ~
11.51N
Force required by cutting blade to shear the grass is given by;
Assume,
F = 11 N
F =T/R
Where,
T = Shaft torque =?
R = Radius of cutting blade=4cm
T = F R
T = 11*0.04
T = 0.44 Nm
Results and Discussion

29. Cont…
But, shaft power is given by;
P =2NT/60
Where,
P = Power developed by shaft;
T = Torque required; and
N = Shaft speed in Rev/min = 10,000 rpm
P = 2NT/60
P = 2*3.1415*10000*.44/60
P = 460 watt

30. Results
➢ Speed of lawn mower:
Circumference of wheel
C = 3.142 x d=3.142x6 = 18.84 cm
➢ Speed of movement of the device:
= (N1/60) x C
= (200/60) x 18.84x10^-2 = 0.628 m/s
= 0.628*3600/1000= 2.262 km/hr
➢ Battery charging time:
Current produced by solar panel I = P/V
P = 2*12 = .24 watt
Charging time = Battery capacity/current
= 36/ 2 = 18 hrs.

31. Results
➢ Power required to drive the lawn mower:
Force F = m x g
= 2 x 9.81 = 19.62 N
Power,
P = F x V
= 19.62 x 6= 117.72W
➢ Angular velocity of the blade:
ω= 2πN3/60
= 2 x π x (10000)/60
= 1046.66 rad/sec

32. Results
➢ Power produced by wheel motor
Effective mass on each motor, m’
= .5 kg
Force F = m x g
= .5 x 9.81 = 4.950 N
Radius of the wheel, r1 = d/2
= 0.06/2 = 0.03 m
Torque produced T= F x r1
= 4.950 x 0.03= .14 N-m
Power = (2 x π x N1 x T)/60
= (2 x 3.142 x 200 x .14)/60 = 2.95W
➢ Total power produced by 4 wheels:
P = 2.95 x 4 = 11.72 W

33. Ramiz Khuram 2017-BT-MECH-720

34. Comparison between solar and IC engine cutter
Sr No Particular Solar Based Grass Cutter IC Engine Grass Cutter
1 Pollution No Greater Factor
2 Fuel No Fuel Consumption Major Factor
3 Friction Greatly Reduced High
4 Cost Low High
5 Maintenance Low High
6 Load Carrying Capacity Low High

35. Advantages
➢ The use of solar power saves the non-renewable energy.
➢ Obstacle is automatically avoided.
➢ Non skilled person can also operate.
➢ It is pollution free.
➢ No required any external supply.
➢ It is economical.
➢ Compact in size and portable.
➢ No any fuel cost.
➢ Easy to move from one place to another place.
➢ Freedom from long extension wires.

36. Applications:
➢ In agriculture
➢ In gardens
➢ Big lawns
➢ For hospitals.
➢ For collages.
➢ Other private places.
➢ All playing grounds.

37. ➢ The work done on lawn mower will meet the challenge of
environmental production and low cost of operation since there is no
cost for fueling.
➢ This lawn mower has been developed for the use of residences and
establishments that have lawns where tractor driven mowers could not
be used.
➢ The machine has proved to be a possible replacement for the gasoline
powered lawn mowers.
Conclusion

38. Work Plan
Tasks
September
2019
October
2019
November
2019
December
2019
January
2020
February
2020
September
2020
October
2020
Literature Review
Selection of Project
Designing Selection of Material
Fabrication
Final Project Submission

39. Future Recommendation
➢ We completed our project successfully with the available sources.
➢ The results and modifications are not up to the expectations.
➢ This efficiency can be increased by using some other modifications
• Design of Blade
• Type of grass that to be cut
➢ The project which we have done surly will reach the average families because the grass can be cut with
minimum cost and with minimum time.
➢ Finally this project may give an inspiration to the people who can modify and can obtain better results.

40. DESCRIPTION QTY UNIT PRICE Total
4 Wheel Robotic Car 1 1250 1250
2 Photovoltaic Solar Panel 6V 2 1000 2000
HC-SR04 Ultrasonic Distance Measuring Ping Sensor 1 300 300
L293D Motor Driver 1 370 370
A2212 1000 KV BLDC Motor 1 900 900
Dry cell battery for charging 1 100 100
ESC 30A Speed Controller 1 900 900
LIPO BATTERY 2200MHA 1 2400 2400
Mounting Bracket for US Sensor 1 80 80
Jumper Wires for Bredboard 1 140 140
T Plug Connector 1 70 70
Original 2200 mah Rechargeable cell 2 250 500
Casing for dry cell 1 150 150
Multi Servo tester 1 350 350
RC IMAX B3 Lipo Battery Charger 1 800 800
Arduino UNO DIP R3 with usb cable 1 700 700
SG90 9g Mini Micro Servo Motor 1 400 400
2 Pin on Off Switch Rocker Switch 1 20 20
Grand Total 11430

41. 10. References
➢ Abhraham, D., Sebastian, Joseph, Prof. John (2017). Solar Powered Fully Automated
Grass Cutting Machine. International Journal of Advanced Research in Electrical,
Electronics and Instrumentation Engineering. 6(4): 2520-2524. Andre Colens, U.S.
Patent 5,444,965, Continuous and autonomous mowing system August 29, 1995.
➢ G. Kumar, G. S., J. Chowdary, D. Aparna, V. Kumar (2017). "Solar Grass Cutter
Robot with Obstacle Avoidance." International Journal of Engineering Science and
Computing, 7(4): 6293-6295.
➢ Prof. S.M.Patil, P., Snehal, Dhanashri (2018). "Smart Solar Grass Cutter With Lawn
Coverage." International Research Journal of Engineering and Technology (IRJET)
5(3): 3476-3479.
➢ Pandey, M., Panchal, Paralkar,Kumar (2018). "Fabrication of Automatic Solar Lawn
Mower." International Journal of Innovative Research in Science, Engineering and
Technology 7(4): 3729-3736.

42. Cont…..
➢ G. Rahul (September,2014). "Solar grass cutter with linear blades by using scotch yoke
mechanism." International research journal of engineering and application. 04(09).
➢ Bhosale Swapnil, K. S. (2017). "Solar powered automatic grass cutter." International Research
Journal of Engineering and Technology (IRJET) 04(0).
➢ Hr. Lamnaton, E. P., V. Belessiotis and N. Kyriakis (2012). "Experimental investigation and
thermodynamic analysis of a solar drier using an evacuated tube air collector." 94: 232-243.
➢ Praful P. Ulhe, M. D. I., Fried D. Wankhede and Krushankumar S. Dhakle (2016).
"Modification of Solar Grass Cutting Machine." International Journal for Innovative Research
in Science and Technology 2: 2349-6010.