Obstacle Avoidance Robot is powered by Arduino, Ultrasonic Sensor, and Servo Motor.

1. Obstacle
Avoidance Robot
Powered by Arduino

2. CircuitComponents Working Source Code Scope

3. Components

4. Components /
1. Chassis 2. Arduino UNO 3. DC Motor
4. Motor Driver 6. Servo Motor5. Ultrasonic Sensor

5. Components /
1. Chassis
• Good quality robotic chassis for DIY
projects
• Laser cut super smooth double layer
acrylic chassis
• Contains Ultrasonic Sensor and Servo
Motor holder

6. Components /
2. Arduino UNO
Microcontroller ATmega328P
Operating Voltage 5V
Input Voltage 7-12V (recommended)
6-20V (limit)
Digital I/O Pins 14
PWM Digital I/O Pins 6
Analog Input Pins 6
SRAM 2 KB (ATmega328P)
EEPROM 1 KB (ATmega328P)
BUILTIN LED 13
Dimension 68.6 mm X 53.4 mm
Weight 25g

7. Components /
2. Arduino UNO
Open Source Hardware: Schematics
• Arduino Uno is open-source hardware! You
can build your own board
Programming
• The UNO is the best board to get started with
electronics and coding
• The Arduino Uno can be programmed with
the Arduino Software IDE
Power
• The Arduino Uno board can be powered via
the USB connection or with an external
power supply from 6 to 20 volts. The power
source is selected automatically

8. Components /
3. DC Motor
Voltage 3-6V DC
Reduction Ratio 1:48
Maximum torque 800k.cm
Material Plastic
Weight 2.4 ounces
Load Current 70mA (250mA MAX)
No-load Speed 1:48 (3V)

9. Components /
4. L298N Motor Driver
Driver Dual H Bridge Motor Driver IC
Operating
Voltage
7 to 35V
Peak Current 2A
Max Power
Consumption
20W (When the temperature
T = 75 °C
Weight 33g

10. Components /
5. HC-SR04 Ultrasonic Sensor
Operating Voltage 5V
Theoretical Measuring
Distance
2cm to 450cm
Practical Measuring
Distance
2cm to 80cm
Measuring Angle
Covered
<15°
Operating Current <15mA
Operating Frequency 40Hz

11. Components /
6. SG90 Micro Servo Motor
Operating Voltage 5V
Torque 2.5kg/cm
Operating Speed 0.1s/60°
Gear Type Plastic
Rotation 0°-240°
Weight 9g

12. Working

13. Working /
1. Calculating the Distance
• Ultrasonic signals travel at the speed of sound
• At 20°C the speed of sound is 343 m/s
• Time measured by HC-SR04 is for return trip
• Divide time in half to calculate distance
𝐷 = (Δt/2) × 𝑐
Δt = Time Delay
C = Speed of Sound
D = Distance Measured

14. Working /
2. Controlling the Speed and Direction of DC Motor
Motor A Enable:
• 5Volts = Enabled
• Ground = Disabled
• PWM = Speed Control
Motor A:
• Input 1: 5 Volts = Forward
• Input 2: Ground = Forward
Motor A:
• Input 1: Ground = Reversed
• Input 2: 5 Volts = Reversed
*Motor B Inputs work the same way
Pulse Width Modulation (PWM)

15. Working /
3. Using Servo Motor to Rotate Ultrasonic Sensor
• SG90 Micro Servos use DC motors
• Potentiometer is used as feedback sensor
• Internal controller board monitors and adjust position
• Position controlled using Pulse Width Modulation (PWM)
Torque
• Amount of force servo can apply to a lever
• Measured in kilogram centimetres (kg-cm)
• Rated Torque: 2.5 kg-cm

16. Circuit

17. Circuit /
Obstacle Avoidance Robot Schematic

18. Source
Code

19. Source Code </> /
Move Forward Function

20. Source Code </> /
Move Backward Function

21. Source Code </> /
Turn Right Function

22. Source Code </> /
Turn Left Function

23. Source Code </> /
Move Stop Function
Distance Calculator Function

24. Source Code </> /
Look Right Function
Look Left Function

25. Source Code </> /
Pin Declaration

26. Source Code </> /
Arduino Setup Code

27. Source Code </> /
Arduino Loop Code

28. Scope

29. Scope /
Further Improvements and Future Scope
1. Adding a Camera
• If interfaced with a camera, robot can be driven beyond line of sight
• Range becomes practically unlimited as network have a large range
2. Use as a fire fighter robot
• Addition of temperature sensor, water tank required
• Required some changes in programming
• It can work as an autonomous fire extinguisher
3. Obstacle detection for a Mining Vehicle
4. Driverless vehicles running along beams
5. Obstacle detecting system for a motor vehicle
6. Autonomous cleaning robot

30. Thank You