Simultaneous localization and mapping (SLAM) with an ... ... Simultaneous localization and mapping (SLAM) is a problem in which an autonomous robot is required to initiate in an unknown

Simultaneous localization and mapping (SLAM) with an autonomous robot

Md. Shadnan Azwad Khan 13321076

Shoumik Sharar Chowdhury 17141025

Nafis Rafat Niloy 13115001

Fatema Tuz Zohra Aurin 13101025

Supervisor: Dr. Tarem Ahmed

Co-Supervisor: Moin Mostakim

Submitted to:

Department of Electrical and Electronic Engineering

School of Engineering and Computer Science

BRAC University

Declaration

We, hereby declare that this thesis project, neither in whole or in part, has been

previously submitted for any degree. It has been completed based on the knowledge we

have acquired and implemented ourselves. Materials of work accomplished by others and

the references gained from the official websites are mentioned by reference.

____________________________

Md. Shadnan Azwad Khan

____________________________

Shoumik Sharar Chowdhury

____________________________

Nafis Rafat Niloy

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Fatema Tuz Zohra Aurin

Under the supervision of,

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Dr. Tarem Ahmed

Assistant Professor

Department of Electrical and

Electronic Engineering

Acknowledgement

We have been, throughout this thesis, fortunate to have the support of our friends, family and

mentors. In particular, we would like to thank our supervisor Dr. Tarem Ahmed for guidance,

patience and for taking immense interest in our work, and Moin Mostakim for sharing his

knowledge and insight on some of the finer algorithms we had to work with. We are grateful

for the support from the esteemed faculties and technicians of the School of Engineering and

Computer Science. This thesis would not have been possible without their help.

List of Figures

1. Rover locomotion. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .10

2. A map produced by the Arduino Rover project. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

3. Raspberry Pi 3 Model B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14

4. Raspberry Pi 3 Model B pin diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

5. Ultrasonic Range Sensor HC SR04 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

6. HC SR04 connection diagram for 3.3V GPIO operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

7. Inertial Measurement Unit (IMU) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

8. Figure 8. Wheel encoder with wheel, motor and brackets . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17

9. Oscilloscope capture of encoder outputs with the wheel spinning at 630 RPM . . . . . . . . . 18

10. L298N stepper motor driver . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

11. Pseudocode for sensor sweep . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . .25

12. Pseudocode for dead reckoning . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . . . . . . 26

13. The movement prediction using rotary angles . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

14. The block diagram of the Kalman filter designed for dead reckoning . . . . . . . . . . . . . . . . . 29

15. Applying transform over robot position and sonar measurement to recognize occupied

cells . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31

16. Pseudocode i for navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33

17. Pseudocode ii for navigation. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34

18. An example of what the Matplotlib library does. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

19. Actual map from survey of room. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

20. Map obtained from SLAM. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .37

List of Tables

1. GPIO connections to sensors and actuators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

2 .Hardware expense. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . . . . .22

3. Sonar uncertainty. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

Content

Abstract 1

1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2

1.1 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3

1.2 Thesis Outline . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

2. Literature Review . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6

2.1 SLAM Approaches . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6

2.2 Related Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10

3. Hardware Specification . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .13

3.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . …. . . . . . . . . . . . . . . . . . . .13

3.1.1 Raspberry Pi 3 Model B . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

3.1.2 Sonar Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15

3.1.3 Inertial Measurement Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 17

3.1.4 Wheel, Gear Motor and Wheel Encoder . . . . . . . . . . . . . . . . . . . . . . . . . . 17

3.1.5 Motor Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

3.1.6 Power Supply Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19

3.2 Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

3.2.1 Robot Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

3.2.2 Hardware Expense . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

4. SLAM Implementation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23

4.1 Relative Positioning and Kalman Filtering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 25

4.1.1 IMU data handling. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26

4.1.2 Wheel encoder odometry. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 27

4.1.3 Dead Reckoning with Kalman filter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28

4.2 Occupancy Grid Mapping . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29

4.2.1 Sonar data and uncertainty modelling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30

4.2.2 Occupancy grid map method . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31

4.3 Navigation and Exploration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

4.3.1 Motor controller operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

4.3.2 Exploration Strategy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 32

4.4 Graphical Representation . . . . .. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35

5. Experimental Results and Evaluation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 36

6. Concluding Remarks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

6.1 Applications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .38

6.2 Limitations and Future work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 38

6.3 Conclusion . . . . .