Grad Report Hardware

An-Najah National University
Faculty of Engineering and Information
Technology
Computer Engineering Department
Hardware Graduation Project
Tennis Ball Collector
Prepared by:
Asala Tibi
Hala Barqawi
Supervised by:
Dr. Asmaa Afeefi
Presented in practical fulfillment of the requirements of
Bachelor degree in Computer Engineering.
May,2023

Acknowledgments
We would like to express our sincere gratitude to all those
who have contributed to the completion of this project.
First and foremost, we are grateful to God for the bless-
ings, and strength bestowed upon us throughout this project.
We extend our deepest appreciation to our supervisor,
Dr. Asmaa Afeefi, for her guidance, expertise, and con-
tinuous encouragement. Our heartfelt thanks go to our
friends who provided valuable insights and support all the
time.
Lastly, we are indebted to our families for their unwa-
vering support, understanding, and patience. Their love
and encouragement have been a constant source of moti-
vation.
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Abstract
Tennis, a widely popular game, is a racket sport that takes
place on a rectangular and flat surface court. During ten-
nis training sessions, manually collecting the balls can be
a laborious task , and the process of retrieving the balls
manually can be time-consuming and physically demand-
ing.
This project aims to address the laborious task of man-
ually collecting tennis balls during training sessions by
developing an autonomous robotic tennis ball collector.
The objective is to design a robot capable of navigat-
ing the tennis court, detecting tennis balls using image
processing techniques, and autonomously collecting them,
thereby allowing players to rest instead of manually re-
trieving the balls. The robot features four independently-
actuated wheels. A gate mechanism is employed to push
the tennis balls into a basket mounted on the robot. A
camera mounted on the robot captures images, which are
processed using OpenCV libraries on a Raspberry Pi to
detect tennis balls through an edge detection algorithm.
This project presents an effective solution for automat-
ing the collection of tennis balls during training sessions,
providing convenience and relief to players from the man-
ual collection task.
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Contents
1 Introduction 7
1.1 Problem ................... 7
1.2 Objectives .................. 7
1.3 Significance of The Work . . . . . . . . . . 8
2 Constraints and Earlier course work 9
2.1 Constraints . . . . . . . . . . . . . . . . . 9
2.2 Earlier course work . . . . . . . . . . . . . 9
3 Literature Review 10
4 Methodology 12
4.1 Description of selected design . . . . . . . . 12
4.2 Mechanical Part . . . . . . . . . . . . . . . 12
4.2.1 Wheels................ 13
4.2.2 Gate ................. 13
4.2.3 Storing area . . . . . . . . . . . . . 13
4.3 Controller Part . . . . . . . . . . . . . . . 13
4.3.1 Arduino uno . . . . . . . . . . . . . 13
4.3.2 Raspberry Pi 3 Model B . . . . . . 14
4.4 Power source . . . . . . . . . . . . . . . . . 14
4.4.1 Power bank 5v . . . . . . . . . . . . 14
4.4.2 Raspberry Power Cable . . . . . . . 14
4.4.3 Lithium battery . . . . . . . . . . . 15
4.5 Electronics . . . . . . . . . . . . . . . . . . 16
4.5.1 Wires................. 16
4.5.2 Servo motor . . . . . . . . . . . . . 16
4.5.3 Ultrasonic Sensor . . . . . . . . . . 16
4.5.4 Raspberry Pi Camera . . . . . . . . 16
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4.5.5 H bridge Motor driver L298N . . . . 17
4.6 Image Processing . . . . . . . . . . . . . . 17
4.6.1 Image Acquisition . . . . . . . . . . 18
4.6.2 Filtering . . . . . . . . . . . . . . . 18
4.6.3 HSV Mask Operations . . . . . . . 19
4.6.4 Edge Detection . . . . . . . . . . . 20
4.6.5 Circle Detection . . . . . . . . . . . 20
4.7 Circle Detection for tennis ball. . . . . . . 22
4.8 Implementation . . . . . . . . . . . . . . . 23
4.8.1 Raspberry pi . . . . . . . . . . . . 23
4.8.2 Arduino Uno . . . . . . . . . . . . 23
5 Discussion 25
5.1 Limitation .................. 25
5.2 Final Result . . . . . . . . . . . . . . . . . 25
6 Conclusion/ Recommendations and Future
Works 26
6.1 Conclusions . . . . . . . . . . . . . . . . . 26
6.2 Future Work . . . . . . . . . . . . . . . . . 27
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