Autonomous lawn mower

Project Title

Autonomous lawn mower

Project Area of Specialization Electrical/Electronic EngineeringProject Summary

Existing lawn cutting machines suffer from more than one of the following; high initial cost, high levels of engine noise, high running cost due to high fuel consumption rates, need for perimeter wires around the field to be trimmed and high operator’s fatigue in long-run due to vibration, noise and other characteristics caused by different types of lawn. Hence the need for a system that can achieve the same cutting effect as the existing lawn mowers with little or no operator’s fatigue, removing IC engine minimized noise pollution, reduced human effort, and running cost. Design and development of prototype model for the automated lawnmower (ALM), that cut grass automatically with little human intervention using a linear blade driven by a robotic car which is powered by a battery. It can be operated in semi-autonomous and full autonomous mode by using a camera to minimized running cost, no health hazard on the operator and it does not have any effect on the environment.

Project Objectives

The objective of this project is to design and implement a Behavior-Based Lawn Mower Robot controller that can be used to mow grass from lawns and playgrounds autonomously. The controller uses a “sense-act” approach to work in a dynamic, unstructured, and unknown environment without having any reliance on surrounding world information. The controller is implemented using Motor Schema architecture, which uses continuous response encoding and cooperative coordination method for behavior coordination. A set of concurrently running behaviors are defined to perform mowing operations. Sonar ranging is used to detect and avoid obstacles. Global Positioning System (GPS) is used for global positioning. The camera is used to detect grass field and utilized to differentiate between mown and un-mown grass.

Project Implementation Method

A fully Automatic grass cutter machine is used to cut the grass at desire heights using rechargeable batteries. Two DC batteries are used along with two vehicle motors for forwarding movement of the cutter as well as for steering and a high-speed high torque DC motor for the cutter.

Phase I:

The first phase involves the configuration of sensors with Raspberry Pi.  

1. Sonar sensors to detect distance for collision warnings
2. IR sensors to detect grass length
3. Camera Interface involves image processing for Intelligent controlled of field parameters (AI, Machine learning, etc.).
4. Raspberry Pi interface

Phase II:

It includes the development and control of mechanical structure design (chassis)

1. Mechanical Structure Design For Automated Lawn Mower (ALM)
2. Motor controller for Grass cutting Blades (BLDC Motor) and driving the wheels (DC Servo Motor)
3. Raspberry Pi interface for automatic control of ALM
4. Selection of Battery and Power Calculations
5. Complete Prototype Test

Benefits of the Project

• Semi-autonomous and full autonomous mode
• Minimized running cost
• No IC Engine
• No health hazard
• No environment effect
• Reduce human effort

Technical Details of Final Deliverable

1. Cutting height between 2 to 4 inches
2. Maximum height of grass field for mover operation 8 inches  
3. BLDC 12V Motor
4. DC Servo motor 12V
5. Operating voltages: 12V.
6. Obstacle detection range: up to 5 meters
7. Mechanical structure design prototype.
8. Cut grass automatically with little human intervention
9. Powered by a battery
10. Plug and play system.

Final Deliverable of the Project HW/SW integrated systemCore Industry OthersOther Industries AgricultureCore Technology OthersOther Technologies Artificial Intelligence(AI), Internet of Things (IoT), RoboticsSustainable Development Goals Industry, Innovation and Infrastructure, Sustainable Cities and CommunitiesRequired Resources

Item Name	Type	No. of Units	Per Unit Cost (in Rs)	Total (in Rs)
			Total in (Rs)	73724
8mp camera module	Equipment	1	5000	5000
Raspberry Pi	Equipment	1	11500	11500
Sonar and IR sensors modules	Equipment	4	1210	4840
Mechanical Chassis Design	Equipment	1	15000	15000
BLDC Motor and Controller	Equipment	2	2480	4960
DC Servo Motor and Controller	Equipment	2	8220	16440
Lithium ion Battery	Equipment	2	4242	8484
Miscellaneous	Miscellaneous	15	500	7500