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Chapter 1

INTRODUCTION

1.1. Description of the Project

Robot - an electromechanical device automates the work in many applications like

household application, military application, commercial application and industrial

application. Robots are reliable means to bring objects, do settings at places where

human interventions are is rather impossible or can cause hazardous effects to human

health.

Our project consists of two parts:

1. One remote controlled robot

2. One android device for controlling the robot

The robot is capable of going to remote places where human presence might not be

possible or dangerous. The robot consists of an onboard camera which sends live video

to the controlling device. The movement of the robot can be controlled by the Android

device, as per the objective of the user, while watching the live video.

1.2. The Objectives

• A wirelessly controlled robot capable of transmitting remote images over large

distances.

• The robot should be highly maneuverable.

• The robot must have secure communications capability.

• The robot is to be medium sized and robust.

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1.3. Objectives’ Details

• Real-time streaming of audio and video

Quality video of minimum 480p at 15 FPS should be transmitted within a low

bandwidth constraint.

• Controlled by any device capable of Wi-Fi (Android, iOS, PC)

To make the robot flexible in control, any device capable of Wi-Fi connectivity will

able to control the robot from remote location.

Expected range of at least 50 meters in direct line-of-sight.

• All-Terrain-Vehicle

Robot should be able to overcome minimum slope of 30 degrees. An average weight of

4kg should be carried, including the robot weight. Self-reconfigurable capabilities are

to be enhanced for all-terrain exploration.

• Secure communications channel between Robot and Controller

Use of secure protocols over Wi-Fi to ensure tamper-proof operation of robot. Viable

options are SSL over TCP, SSH.

• Extensible platform for future enhancements

The robot is to be highly extensible, with possibility of adding features in the future as

required, using modular design.

1.4. Existing Trends and Requirements

Autonomous Robots fail in the applications where harsh decisions and expert person

handlings are required. Even though autonomous bots have the capabilities of self-

navigation, decision-making and artificial intelligence, they are not suitable for the

applications like bomb defusing, nuclear power plants, military applications etc. Cost

and intellectual expenses of building autonomous robots are pretty much high too.

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Looking to the present demands of robots in today’s developing world to carry out,

work effectively and accurately, the appropriate development of robot in the cost

effective manner is required. This development helps many industries, workplaces and

research development centers to utilize robots in place of humans.

More to that, robots that have the programming logic to do the desired task but the

decision power lying in the hands of the controller (human) are preferred.

Looking at the present scenario, we have proposed the idea of building robot that

● Can be controlled by a controller from remote place based on the video sent

from robot.

● Should be a non-autonomous robot.

● Robot should be made from the basic cost effective materials like

Webcam/Camera, Wireless Adapter, etc.

1.5. Scopes

The project aims at designing the robot that can be controlled wirelessly by the use of

a handheld android device that can be used as a remote controller to the robot. The robot

can be applied in a versatile range of applications ranging from home use to operations

in hostile and inaccessible locations.

The robot has a mounted camera so it is essentially a versatile, moving camera that may

be applied in the following fields:

The robot can be used in rescue mission

During natural calamities, the robot can be sent into inaccessible areas for recon

mission, or to make contact with personnel who might be trapped.

For remote mapping of hostile territory or geographical analysis

Using 3D distance sensors, the environment around the robot can be mapped to

very high accuracy. The generated map can be used for recon, analysis and

planning.

To safeguard national properties

The robot can be deployed into national parks, museums, borders, and so on to

monitor suspicious activities like smuggling, poaching.

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1.6. Technology Exposures That Project Provides:

1. Google’s Android open source technology.

2. Wi-Fi technology.

3. Interfacing Wireless Adapter to Microcontroller.

4. DC motor working and need for a Motor driver.

5. Interfacing of Robot DC motors to Microcontroller.

6. Embedded programming.

7. PCB designing.

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Chapter 2

PLANNING, ANALYSIS AND DESIGN

2.1. Decomposition of Problems

Figure 1 - Decomposition of Problems

2.2. Proposed Solution

Here on the robot, a Wi-Fi adapter is interfaced with the Raspberry Pi, to which a

camera is connected. A controller is a client using Android tablet/phone in range of

Wi-Fi administers the robot. Whenever a client sends the control signal (GPIO

command to Rasp-Pi), it is transmitted wirelessly and is captured by the Wi-Fi adapter

interfaced with Rasp-Pi. Rasp-Pi analyzes this signal and it takes appropriate action to

rotate the motor i.e., either clockwise or anticlockwise. Due to this we can control the

movement of robot either in forward or backward direction. A camera mounted on the

robot captures the video and transmits it to the client, which gives the current position

of the robot. Based on that video we can determine whether we need to move the

robot.

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Figure 2 - System Block Diagram

• Mechanics: 4 wheel drive configuration

• Processing: Raspberry Pi/ Beagle Bone/ mini-ATX PC/ Custom System

• Camera/Vision: Raspberry Pi 5 MP Camera Module/ USB Camera

• Wireless: Wi-Fi USB adapter

• Power: Separate power for electronics and actuation systems

Advantages of Wi-Fi over other wireless technologies like Bluetooth and ZigBee:

Bluetooth is generally used for point to point networks and Bluetooth operates at a

much slower rate of around 720 Kbps which is very small for video transfer or

moving large amount of data like the image captured from a camera, whereas the

bandwidth of Wi-Fi can be up to 150Mbps and very ideal for video transmission.

Wi-Fi is very much secure means of communication than Bluetooth.

Wi-Fi connection to send video, audio, and telemetry operation, while accepting

remote control commands from an operator who can be located virtually anywhere in

the world.

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Robots are already being eyed for obvious tasks like conducting search-and rescue

missions during emergencies or hauling gear for soldiers in the jungle or woods. The

mechanics of the robot uses the concept that has been developed to ensure robust

navigation, search and transportation in rough terrain.

2.3. Solution Details

Hardware Environment

• Actuation/Mechanical

4 wheels of 7-10 cm diameter connected to high speed, high torque motor

each.

Two wheels on each side placed relatively close to allow easier turning.

Low height and batteries placed at the bottom of the robot for low CG and

hence stability.

• Control electronics

Raspberry Pi as the controller for its processing power and large developer

community.

Two L293Ds driving the motors.

Software Environment

1. Android Developer Tools (ADT) - to build the android application to receive

the live video feed from the camera and to send the control signals to control

the robot.

2. WiringPi library from Gordon Projects - GPIO interface library for the

Raspberry Pi.

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2.4. Activity Diagrams

Figure 3 - Activity Diagram for Camera View

Figure 4 – Activity Diagram for Motors Control

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2.5. Project Development Period

Our work through this project can be broken up into the following sections, which is

depicted in figure 2.

2.5.1. Experimentation

This involves testing the devices that are going to be used in the project, determining

what they are capable of, and developing simple algorithms

2.5.2. Design

Create mock-up designs of both hardware (Mechanical structure of the robot and circuit

layout to be integrated into robot) and software (Android application to control the

robot).

2.5.3. Development

Development of the android application, mechanical structure of the robot, circuit

layout for the robot’s mobility and wireless communication between the android device

and robot. Carry out testing ourselves during development.

2.5.4. Testing

Test complete system on a small range area and identify any final bugs. Interview the

project coordinator and for the evaluation of the system.

Figure 5 - Water Fall Model

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2.5.5. Real-World Testing

Testing of the complete system in a real-world environment to get the knowledge of

how the system works.

2.5.6. Final Report

Write final report on the development of the system, and complete documentation.

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2.6. Project Cost

SN Part Qty. Cost (NRs)

1 Raspberry Pi 1 6000

2 Raspberry Pi Camera 1 2300

3 DC motors 4 1500

4 Mechanics (Wheels, Acrylic Glass, Metal) Multiple 2000

5 Wi-Fi adapter 1 1500

6 Power Electronics Multiple 1000

7 Batteries Multiple 3000

Total 17300

Figure 7: Project Cost Details

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Chapter 3

Implementation and Coding

The implementation details include the construction and programming of the Robot

and the Android device as follows

3.1. Block Diagram

Figure 8 - Block Diagram of the Raspberry Pi Connections

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3.2. Circuit Diagram

Figure 9 - Circuit Diagram of Raspberry Pi Connections

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3.3. Project Module Implementation

3.3.1. Video Transmission - through Wi-Fi

Video transmission is done using the Raspberry Pi Camera Module (5MP). The

transmission resolution is at 480p and 25 fps. The video is viewed on the provided

camera area of the Android screen.

Transmission is done by the Raspberry Pi using GStreamer application. The video

stream is obtained in the Android device using GStreamer SDK with Android SDK.

3.3.2. Robot Control Mechanisms - through Wi-Fi

The robot control is achieved with the Android device using Wi-Fi . The control is

possible by making an SSH connection with the Raspberry Pi and writing control

commands directly on the console by providing a human interface based on motion and

buttons. The motion control is done by using the inbuilt accelerometer of the Android

device. The buttons are controlled using the touch-screen of the Android device.

Figure 10 - The overall design of the Android application

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3.3.3. Android Application

Figure 11 - Live video stream coming from the robot

The Android application was developed using Google’s Android Development Toolkit.

Java is the programming language used to develop the Android application.

The application provides an interface to control and view the robot motion and feed of

video. The robot IP address and other options can be changed in the application itself.

The robot head-lights can also be turned on and off from the application. The robot

motion can be of two types:

● Simple control and

● Sharp turn control

The sharp turn control allows more maneuverability by making the robot able to turn

360 degrees in its central axis.

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3.3.4. Image Capture and Video Recording (Future Scope)

Since the remote video feed is obtained in the local controller, the video can be recorded

locally as well as the image can be captured for future reference and data collection.

The features can be implemented on the Android application and stored in external or

internal memory as desired.

3.3.5. Log maintenance (Future Scope)

The log is maintained by the Linux system that is running on the Raspberry Pi and it

can be extended to the Android application using inbuilt SQLite database system. The

log can be viewed locally on the device or remotely through the internet.

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Chapter 4

CONCLUSIONS

4.1. Applications of the Robot

The robot has a mounted camera so it is essentially a versatile, moving camera that

may be applied in the following fields:

• The robot can be used in rescue mission.

During natural calamities, the robot can be sent into inaccessible areas for

recon mission, or to make contact with personnel who might be trapped.

• For remote mapping of hostile territory or geographical analysis

Using 3D distance sensors, the environment around the robot can be mapped

to very high accuracy. The generated map can be used for recon, analysis and

planning.

• To safeguard national properties

The robot can be deployed into national parks, museums, borders, and so on to

monitor suspicious activities like smuggling, poaching.

4.2. Constraints

Done in a hobby environment, the robot is not currently very robust, or able to

navigate through very rough terrain.

It is a raw prototype and currently done only for research and academic

purpose, and much must be added in order to make it ready for use in the field.

Due to technological limitation our extent of abilities are bound.

The range of distance of operation is limited by the range of Wi-Fi device

used.

Unavailability of high grade parts has made it impossible to make the robot

robust in terms of power consumption, size and overall efficiency.

We had limited time frame to build our robot.

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4.3. Future Development

Being a highly extensible platform, the robot can be enhanced with further features

for the following tasks:

● Improvement of Control Application

The Android application needs to be extended to other platforms like iOS/Windows

Mobile. Features such as recording the live feed or taking snapshots will be added

soon. Also the controls will be made such smoother.

● Remote Image Processing

With our technology, image processing can be done without the need of processing

power in the robot itself. The remote images can be processing locally, and robot

decisions may be sent remotely.

● Automatic navigation

Using satellite GPS, the robot can be given a set path remotely, which it would cover

automatically to reach its’ objective.

● Improved Vision system

Using Night Vision video systems for improved usability during night.

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REFERENCES

L. Geiger and A. Zndorf, “eDOBS - Graphical Debugging for Eclipse”, Brazil,

September 2006.

Rodney, "Achieving Artificial Intelligence through Building Robots", Boston:

Massachusetts Institute of Technology, 1986.

Reto Meier, "Professional Android Application Development", Wiley, Nov 24, 2008.

Mark L. Murphy, "The Busy Coder's Guide to Android Development",

CommonsWare, 2009.

S. Conder and L. Darcey, "Android Wireless Application Development", Addison-

Wesley, 2010.

H.R. Everett, "Sensors For Mobile Robots - Theory and Applications", A.K. Peters,

Ltd., Wellesley, MA, 1995.

Web Resources

The Java Tutorials: http://download-llnw.oracle.com/javase/tutorial/index.html

Android User Interfaces: http://developer.android.com/guide/topics/ui/index.html

Android Developer's Blog: http://android-developers.blogspot.com/

Other URLs -

http://www.drrobot.com/

http://www.superdroidrobots.com/

http://developer.android.com/

http://wiringpi.com/

http://www.stackoverflow.com/