Object-Avoidance-Vehicle-using-Arduino-and-Ultrasonic-Sensor

Developed a vehicle that can detect obstacles in its path and automatically change direction to avoid collisions using ultrasonic sensors and Arduino microcontroller.

1. Project Overview

An Object Avoidance Vehicle is an autonomous robot that navigates its environment without human control. It uses ultrasonic sensors to detect obstacles in its surroundings. When the sensor detects an object closer than a defined distance, the Arduino instructs the motors to change the vehicle’s direction — either by turning left, right, or reversing — to avoid a collision.

2. Components Required

Component	Description	Quantity
Arduino UNO / Nano	Main controller to process sensor data and control motor driver	1
Ultrasonic Sensor (HC-SR04)	Detects objects by measuring distance using sound waves	1 or 3 (front, left, right)
Motor Driver (L298N / L293D)	Drives DC motors according to Arduino control	1
DC Motors with Wheels	Provide motion to the vehicle	2
Caster Wheel	Balances the vehicle	1
Chassis (Robot Body)	Base structure to mount all components	1
Battery Pack (7.4V or 9V)	Power supply	1
Jumper Wires, Breadboard	For connections	—

3. Power Supply

• Arduino: 5V (can be powered from motor driver’s 5V output or external power bank)
• Motors: 6–12V (through L298N or L293D)
• Ensure common ground between Arduino and motor driver.

4. Working Principle

1. The ultrasonic sensor (HC-SR04) emits high-frequency sound waves.

2. These waves bounce off obstacles and return as echoes.

3. The sensor measures the time between sending and receiving the signal.

4. The Arduino calculates the distance to the object using the formula:

   [ \text{Distance} = \frac{\text{Time} \times \text{Speed of Sound}}{2} ]

5. If the measured distance is less than a predefined threshold (say 20 cm), it means there’s an obstacle ahead.

6. The Arduino sends signals to the motor driver to stop and change direction (left or right).

7. If no obstacle is detected, the vehicle continues moving forward.

5. Circuit Connections

Component	Arduino Pin	Description
HC-SR04 VCC	5V	Power supply
HC-SR04 GND	GND	Ground
HC-SR04 Trig	D9	Trigger pin
HC-SR04 Echo	D10	Echo pin
Motor Driver IN1	D2	Left Motor Control 1
Motor Driver IN2	D3	Left Motor Control 2
Motor Driver IN3	D4	Right Motor Control 1
Motor Driver IN4	D5	Right Motor Control 2
Motor Driver ENA, ENB	Connected to 5V	Enable signals for both motors

Note: Connect motor power supply to 12V terminal of L298N and Arduino to 5V output of the module.

6. Algorithm

1. Initialize ultrasonic sensor and motor driver pins.
2. Continuously measure the distance in front.
3. If distance > 20 cm → move forward.
4. If distance ≤ 20 cm → stop, move backward briefly, and then turn right.
5. Repeat the process to ensure continuous obstacle avoidance.

7. Block Diagram

[Ultrasonic Sensor] → detects object → [Arduino] → processes data → [Motor Driver] → controls [DC Motors / Wheels].

      +----------------+
      | Ultrasonic     |
      |  Sensor (HC)   |
      +-------+--------+
              |
              v
         +-----------+
         |  Arduino  |
         |  UNO/Nano |
         +-----------+
           |       |
      +----+       +----+
      |                 |
 +----------+      +----------+
 | Motor L  |      | Motor R  |
 +----------+      +----------+
         (Vehicle Movement)

8. Applications

✅ Autonomous robots ✅ Industrial robot navigation ✅ Warehouse delivery robots ✅ Automated cleaning robots (like vacuum cleaners) ✅ Smart car obstacle avoidance systems

9. Advantages

• Fully autonomous operation
• Simple and low-cost design
• Can operate in dynamic environments
• Modular – can add sensors for 360° detection
• Scalable for IoT control via Bluetooth/Wi-Fi

10. Limitations

• Cannot detect transparent objects (ultrasonic reflection issue)
• Sensitive to noise or irregular surfaces
• Turning decisions are fixed (no path optimization)

11. Conclusion

The Object Avoidance Vehicle is a simple yet effective example of autonomous robotics. Using an ultrasonic sensor and Arduino, the vehicle can intelligently detect obstacles and navigate around them without human intervention. This project is ideal for beginners in embedded systems, robotics, and IoT automation, and can be enhanced with multiple sensors, Bluetooth, or Wi-Fi control for more intelligent navigation.

12. Images