Redback-Autonomous-car

Building a lane sensing redback autonomous car prototype using Arduino

Overview

The Redback Autonomous Car project aims to develop an autonomous vehicle capable of navigating a track autonomously. This project involved extensive design, testing, and refinement phases over 8 weeks.

Project Goals

• Cost: Less than $100
• Weight: Less than 500g
• Dimensions: Less than 250mm in all directions
• Performance: Complete 3 laps in under 5 minutes without human intervention

Features

1. Model 1:

   • 4 x rubber medium-sized wheels
   • 1 x 9v battery
   • 1 x battery snap
   • 1 x Arduino Board
   • 2 x motors
   • 2 x phototransistors
   • 2 x white LEDs
   • 3 mm plywood

2. Model 2 (Final Model):

   • 3mm Plywood
   • 1 x Arduino
   • 2 x medium-sized rubber wheels
   • 1 x bearing ball transfer wheel
   • 2 IR sensors
   • 3D printed PLA cover
   • 1 x 11-volt lipo battery
   • 1 x fuse

Design and Development

Challenges and Solutions

• IR Sensors: Initial sensors were unreliable under sunlight. Replaced with line tracing IR sensors for better performance.
• Battery: Switched from a 9V to an 11V lipo battery to provide sufficient current and maintain speed.
• Arduino Issues: Replaced faulty Arduinos to ensure consistent functionality.
• Fuse Issues: Resolved short circuit issues by replacing the fuse and securing wires.

Manufacturing

• 3D Printed Cover: Designed to conceal electrical components, with modifications for weight and aesthetic improvements.

Code

The code was developed to control the vehicle's movement based on sensor input. Key features of the code include:

• Global Variables: Define motor and sensor pins and the PWM duty cycle.
• Initialization Function: Sets the motor and sensor pins as outputs or inputs and prints the configuration to the serial monitor.
• Setup Function: Initializes serial communication and calls the initialization function.
• Loop Function: Reads sensor inputs, determines the direction based on sensor values, and controls the motors accordingly. It also prints sensor readings and the current direction to the serial monitor.

Performance

In the final competition, the vehicle successfully completed 3 laps in 3 minutes and 33 seconds, meeting the project's requirements. Improvements were identified for future development, including optimizing wheel design and enhancing sensor accuracy.

Recommendations

• Wheel Design: Develop lighter and larger radius wheels for improved performance.
• Sensor Integration: Add more IR sensors for better positioning accuracy.
• Code Optimization: Refine the code to leverage additional sensors and improve speed and precision.

Cost Breakdown

Item	Description	Price per unit	Quantity	Cost ($)
Wheels	Plastic Wheel 65 mm	3	2	6
Ballpoint wheels	Mini swivel castor wheels	1.5	1	1.5
Arduino uno	Keystudio uno R3	40	1	40
Plywood	0.003mm thickness	16.15	20cm²	0.66
Lipo Battery	11.1v Lipo battery	20	1	20
3D print	PLA material	-	1	-
Hobby Motor	Plastic geared motor	5.75	2	11.5
IR sensors	Infra-red line trace sensor module for Arduino	5.45	2	10.9
Wires	Covered Copper wires	0.375	12	4.5
Total cost				95.06

Conclusion

The Redback Autonomous Car project demonstrates the potential of autonomous technology in small-scale applications. The team's efforts in design, testing, and iteration highlight the importance of continuous improvement and innovation in engineering projects.