BOMB DISPOSAL ROBOT USING ARDUINO

Introduction

Our project is designed keeping in mind, the view of the current civil wars, military instability and terrorist scenarios across the globe. Almost every day so many trained people gets either injured or loses their lives while dealing with or trying to defuse bombs. All this can be perceived by the countless numbers of news articles and documentaries that appears daily on news channels and print media around the world.

The main idea of the robot here is to serve the bomb disposal squad with proving safety and security from the dangers that they are facing in their daily lives. It has a wireless camera for video feedback so operator can operate more efficiently. The operation of robot is controlled by using wireless module so it can provide more range of operation. Also construct a basic bomb disposing robot which can handle simple work like wire cutting, flip on switches, lift light objects, etc. approaching it for disposal.

Mobile robot reduces or eliminates a bomb technician’s time-on-target. A robot takes risk out of potentially deadly scenarios and lets the bomb technician focus on what to do to an explosive device rather than on the immediate danger to life and limb. Even if a robot cannot reach an item for disruption, it can still be used to relay information to aid in tool and procedure selection to moving downrange. In addition, events recorded by a robot’s camera can provide evidence for further analysis.   

OVERVIEW

The main idea of the robot here is to serve the bomb disposal squad with proving safety and security from the dangers that they are facing in their daily lives. It has a wireless camera for video feedback so operator can operate more efficiently. The operation of robot is controlled by using wireless module so it can provide more range of operation. Also construct a basic bomb disposing robot which can handle simple work like wire cutting, flip on switches, lift light objects, etc. approaching it for disposal. Mobile robot reduces or eliminates a bomb technician’s time-on-target. A robot takes risk out of potentially deadly scenarios and lets the bomb technician focus on what to do to an explosive device rather than on the immediate danger to life and limb. Even if a robot cannot reach an item for disruption, it can still be used to relay information to aid in tool and procedure selection to moving downrange. In addition, events recorded by a robot’s camera can provide evidence for further analysis.   

FEATURES

• The bomb technician will also control the robot using an android phone. This input from the user will be transmitted serially by RF signal to the robot, where it will receive, identify and further instruct the robot module.

• It makes the controlling of the robot such that it can be controlled very easily.

• It allows the user to manipulate the suspicious packet using the robotic arm.

• The input in this project will be from the user.

• The output of the system is then processed into a signal that can instruct the appropriate module.

• This module will be a motor of the wheels of the robot or the robotic arm.

• Can work in the places where no human can operate such as over land mines because of its light weight.

• Can perform spying by providing audio transmission undetected.

• It has a wireless camera for video feedback so operator can operate more efficiently.

• Bomb diffusing operation.
• Easy to control.

HARDWARE DESCRIPTION

COMPONENTS USED

The components used in our project are listed below.

COMPONENTS DESCRIPTION.

Arduino

Arduino is an open source microcontroller which can be easily programmed, erased and reprogrammed at any instant of time. Introduced in 2005 the Arduino platform was designed to an inexpensive and easy way for hobbyists, students and professionals to create devices that interact with their environment using sensors and actuators. Based on simple microcontroller boards, it is an open source computing platform that is used for constructing and programming electronics device. It is also capable of receiving and sending information over the internet with the help of various Arduino shields, which are discussed in this paper. Arduino uses a hardware known as the Arduino development board and software for developing the code known as the Arduino IDE (Integrated Development Environment). Built up with the 8-bit Atmel AVR microcontroller’s that are manufactured by Atmel or a 32-bit Atmel ARM, these microcontrollers can be programmed easily using the C or C++ language in the Arduino IDE. Unlike the other microcontroller boards in India, the Arduino boards entered the electronic market only a couple of years ago, and were restricted to small scale projects only. People associated with electronics are now gradually coming up and accepting the role of Arduino for their own projects. This development board can also be used to burn (upload) a new code to the board by simply using a USB cable to upload. The Arduino IDE provides a simplified integrated platform which can run on regular personal computers and allows users to write programs for Arduino using C or C++.

The Arduino Uno can be programmed with the Arduino software (download). Select “Arduino Uno from the Tools > Board menu (according to the microcontroller on your board). For details, see the reference and tutorials. The ATmega328 on the Arduino Uno comes preburned with a boot loader that allows you to upload new code to it without the use of an external hardware programmer. It communicates using the original STK500 protocol (reference, C header files). You can also bypass the boot loader and program the microcontroller through the ICSP (In-Circuit Serial Programming) header; see these instructions for details. The ATmega16U2 (or 8U2 in the rev1 and rev2 boards) firmware source code is available. The ATmega16U2/8U2 is loaded with a DFU boot loader, which can be activated on Rev1 boards: connecting the solder jumper on the back of board (near the map of Italy) and then resetting the 8U2.On Rev2 or later boards: there is a resistor that pulling the 8U2/16U2 HWB  line to ground, making it easier to put into DFU mode.

NEED FOR ARDUINO

Why is there a need to use Arduino in specific? or What makes it different from other? Massimo Banzi, a Co-founder of arduino mention some very important reasons for this question.

Active User Community: A group of people using a similar product can hold posted message conversations and share their experiences or solve the problems of the other users in the communities with their own experiences. “IF you start charging for everything, everything dies very quickly.” Says Banzi, Arduino Cofounder.

Growth of Arduino: Arduino was developed with intent to provide an economical and trouble-free way for hobbyists, students and professionals to build devices that interact with their situation using sensors and actuators. This makes it perfect for newcomers to get started quickly.

Inexpensive Hardware: Since Arduino is an open source Platform the software is not Purchased and only the cost of buying the board or its parts is incurred, thus making it very cheap. The hardware designs are also available online for free from its official website.

Arduino Board As a Programmer: To make Arduino board function easy and also making it available everywhere these boards come with a USB cable for power requirements as well as functioning as a Programmer.

Multi-platform Environment: The Arduino IDE is capable of running on a number of platform including Microsoft, Linux and Mac Os X making the user community even larger.

ELEMENTS OF ARDUINO UNO BOARDS

Hardware

Hardware

The Arduino Development Board Consists of many Components that together makes it work. Here are some of those maim components blocks that help in its functioning:

Microcontroller: This is the heart of the development board, which works as a mini computer and can receive as well as send information or command to the peripheral devices connected to it. The microcontroller use differs from board to board it also has its own various specifications. Version of this microcontroller is R3.

External Power Supply: This power supply is used to power the Arduino development board with a regulated voltage ranging from 9-12 volts.

Internal Programmer:.The developed software code can be uploaded to the microcontroller via USB port, without an external programmer

Reset Button:This button is present on the board can be used to resets the Arduino microcontroller.

Analog Pins: There are some analog input pins ranging from A0-A7 (typical). These pins are used for the analog input/ output. The no. of analog pins also varies from board to board.

Digital I/O Pins:There are some digital input pins also ranging from 2 to 16 (typical). These pins are used for the digital input/output. The no. of these digital pins also varies from board to board.

Power And GND Pins:There are pins on the development  board that provide 3.3, 5 volts and ground through them.

FEATURES OF THE ARDUINO BOARD

It is an easy USB interface. This allows interface with USB as this is like a serial device.

The chip on the board plugs straight into your USB port and supports on your computer as a virtual serial port. The benefit of this setup is that serial communication is an extremely easy protocol which is time-tested and USB makes connection with modern computers and makes it comfortable.

It is easy-to-find the microcontroller brain which is the ATmega328 chip. It has more number of hardware  features like timers, external and internal interrupts, PWM pins and multiple sleep modes.

It is an open source design and  there is an advantage of begin open source is that it has a large community of people using and troubleshooting it. This makes it easy to help in debugging projects.

It is a 16 MHz clock which is fast enough for most applications and does not speeds up the microcontroller.

It is very convenient to manage power inside it and it had a feature of built-in voltage regulation. This can also be powered directly off a USB port without any external power. We can connect an external power source of upto 12v and this regulates it to both 5v and 3.3v.

13 digital pins and 6 analog pins. This sort of pins allows to  connect hardware to our Arduino Uno board externally.These pins are used as a key for extending the computing capability of the Arduino Uno into the real world. Simply plug our electronic devices and sensors into sockets that correspond to each of these pins and we are good to go.

This has an ICSP connector for bypassing the USB port and interfacing the Arduino directly as a serial device. This port is necessary to re-bootland our chip if it corrupts and can no longer used to our computer.

It has a 32 KB of flash memory for storing our code.

An on-board LED is attached to digital pin 13 to make fast the debugging of code and to make the debug process easy.

Finally, it has a button to reset the program on the chip.

Motor driver

The L298N is an integrated monolithic circuit in a 15-lead multi watt and power SO20 packages. It is a high voltage, high current dual bridge driver de-signed to accept standard TTL logic level stand drive inductive loads such as relay, solenoids, DC and stepping motors. Two enable inputs are provided to enable  or disable the device independently of the input signals. The emitters of the lower transistors of each bridge are connected together and the corresponding external terminal can be used for the connection of an external sensing resistor. An additional supply input is provided so that the logic works at a lower voltage.

BRIDGE DC MOTOR CONTROL

On the other hand, for controlling the rotation direction, we just need to inverse the direction of the current flow through the motor, and the most common method of doing that is by using a H-bridge circuit contains four switching elements, transistors or MOSFETs, with the motor at the center forming a H-like configuration. By activating two particular switches at the same time we can change the direction of the current flow, thus change the rotation direction of the motor. So if we combine these two methods, the PWM and the H-bridge, we can have a complete control over the DC motor. There are many DC motor drivers that have these features.

FEATURES

High operating voltage, which can be up to 40 volts;

Large output current, the instantaneous peak current can be up to 3A;

With a 25W rated power;

Two built in H-bridge driver, large current, full bridge driver, which can be used to driver DC motors, stepper motors, relay coils and other inductive loads.

Using standard logic level signal to control.

Able to drive a two-phases stepper motor or four-phase stepper motor, and two-phase DC motor.

Adopt a high-capacity filter capacitor and a freewheeling diode that protects devices in the circuit from being damaged by the reverse current of an inductive load, enhancing reliability.

The module can utilize the built-in stabilivolt tube 78M05 to obtain 5v from the power supply. But to protect the chip of the 78M05 from damage, when the drive voltage is greater than 12v, an external 5v logic supply should be used.

Drive voltage: 5-35V; logic voltage: 5v

PCB size: 4.2 x 4.2cm

DC Motor

A DC motor is any of a class of rotary electrical machines that converts direct current electrical energy into mechanical energy. The most common types relay on the forces produced by magnetic fields. Nearly all types of DC motors have some internal mechanism, either electromechanical or electronic; to periodically change the direction of current flow in part of the motor. DC motors were the first type widely used, since they could be powered from existing direct current lighting power distribution systems. A DC motor’s speed can be controlled over a wide range, using either a variable supply voltage or by changing  the strength of current  in its field windings. Small DC motors are used in tools, toys, and appliances. The universal motor can operate on direct current but it is lightweight brushed motor used for portable power tools and appliances. The advent of power electronics has made replacement of DC motors with AC motors possible in many applications.

CONSTRUCTION

 An Electric DC motor is a machine converts electric energy into mechanical energy. The working of DC motor based on the principle that when a current –carrying conductor is placed in a magnetic field, it experiences mechanical force. The direction of mechanicai force is given by Fleming’s Left-hand Rule and its magnitude is given by F = BIL Newton.

There is no basic difference in the construction of a DC generator and a DC motor. In fact, the same d.c. machine can be used interchangeably as a generator or as a motor. Like generator DC motor are also classified in to shunt-wound, series-wound and compound-wound.DC motor are seldom used in ordinary applications because all electricSupply companies furnish alternating current. However, for special application such as in steel mill, mines and electric train, it is advantageous to convert altering current into direct current in order to used dc motor. The  reason is that speed/ torque characteristics of d.c motors are much more superior to that of a.c motors. Therefore, it is not surprising to note that for industrial driver, d.c. motor are as popular as 3-phase induction motor.

WORKING PRINCIPLE OF DC MOTOR

A machine that converts DC power into mechanical power is know as a DC motor. Its operation is based on the principle  that when a current carrying conductor is placed in a magnetic field , the conductor experiences a mechanical force. The direction of this force is given by Fleming’s left hand rule and magnitude is given by;

                                                              F = BIL Newton’s

Basically, there is no constructional difference between a DC motor and a DC generator. The same DC machine can be run as a generator or motor. Suppose the conductors under N-pole carry current into the plane of the paper and those under S-pole carry current out of the plane of the paper as shown in figure. Since each armature conductor is carrying current and is placed in the magnetic field, mechanical force acts on it. On applying Fleming’s left hand rule, it is clear that force on each conductor is tending to rotate the armature in anticlockwise direction. All these forces add together to produce a driving torque which sets the armature rotating. When the conductor moves form one side of a brush to the other, the current in that conductor is reversed and at the same time it comes under the influence of next pole which is of opposite polarity. Consequently, the direction of force on the conductor remains the same. It should be noted that the function of a commentator in the motor is the same as in generator.

2.2.4  Battery

A battery is a self-contained, chemical power pack that can produced a limited amount of electrical energy whenever its needed. Unlike normal electricity, which flow to our home through wires that start off in power plant, a battery slowly converts chemicals packed inside it into electrical energy, typically released over a period of days, weeks, months, or even years. The basic idea of portable power is nothing new; people have always hand ways had ways of making energy on the move. Even prehistoric humans knew how to burn wood to make fire, which is another way of producing energy (heart) from chemicals (burning releases energy using a chemical reaction called combustion). By the time of the industrial revolution (in the 18^th and 19^th centuries), we’d mastered the art of burning lumps of coal to make power, so fueling things like stem locomotive.

The basic power unit inside a battery is called a cell, and it consists of three main bits. There are two electrodes (electrical terminals) and a chemical called an electrolyte in between them. For our convenience and safety, these things are usally packed inside a metal or plastic outer case. There are two more handy electrical terminals, marked with a plus (positive) and minus (negative), on the outside connected to the electrodes that are inside. The difference between a battery and a cell is simply that a battery consists of two or more cells hooked up so their power adds together.

When we connect a battery’s two electrodes into circuit (for example, when we put one in a flashlight), the electrolyte starts buzzing with activity. Slowly, the chemicals inside iot are converted into other substances. Ions (atoms with too few or too many electrons) are formed from the materials in the electrodes and take part in chemical reactions with the electrolyte. At the same time, electrons pass from one terminal to other through the outer circuit, powering whatever the battery is connected to. This process continues until the electrolyte is completely transformed. At that point, the ions stop moving through the electrolyte is the electrons stop flowing through the circuit, and the battery is flat.

2.2.5  Robotic Arm

Humans have been able to effectively manipulate objects in their environment with the use of their hands. Features like our opposable thumbs have ensured utmost efficiency in the usage of hands. In the modern world, our hands may not be powerful enough for the kind of applications that we use. Moreover, it may not be safe. And as a solution to this problem, robotic arms have been in use for a while. They are designed to mimic the human hand. They are more powerful and more accurate than the human arm.

They can be modified suitably for any kind of application. Robotic arms are an assemblage of links and joints. They form a kinematic chain. Servo motors are usually placed at the joints in order to bring about movement. In a robotic arm, the hand is usually the toughest part to design. This is because the movement of human fingers is very quick and accurate. And the degrees of freedom of the human hand are also very high. The human hand is also compact at the same time. In order to achieve all these simultaneously with a robotic hand, a complex design must be conceived and implemented. New developments in this field have given rise to detachable magnetic fingers. These sorts of life-like robotic arms are suitable for defusing bombs. Design and Development: The robotic arm is developed with three things in mind to be lightweight, to have a low rotational moment of inertia to provide the maximum degree of freedom for object manipulation. Two materials have been considered to make the arm. For light weight and high strength carbon fiber makes a good choice. The other material that can be used is Acrylic. This is extremely light in weight, but may not be sufficient for rugged use. The servo motors that operate the arm are usually placed on the respective joints. But in the design of the bomb defuse robotic arm the servo motors are placed at the base of the arm, near the centre of the multi rotor copter. This reduces the effect of rotational moment if inertia as the weight of the robotic arm is path to be teaced by the arm concentrated towards the centre of the multi rotor copter. The joints are operated via kinematic chain. In this case, the kinematic chain is a four-bar mechanism. Common robotic arms make use of servo motors at the respective joints. This disturbs the stability of the flight of the drone as the centre of gravity moves away from the centre. The proposed arm will have the joints activated by two four bar mechanism. In this scenario, the servo motors are placed at the base of the arm to activate the four-bar link. Hence the centre of gravity is maintained almost at the centre of the drone and rotational moment of inertia is lowered.

2.2.5.1  Gripper

Grippers, sometimes called hand grippers, are primarily used for testing and increasing the strength of the hands; this specific form of grip strength has been called crushing grip,[1]which has been defined as meaning the prime movers are the four fingers, rather than the thumb. There are differences from brand to brand, but the common features of standard grippers are that they use a torsion spring fitted with two handles. The exact dimensions of these elements very, as well as the materials used to make them; the springs are made from various types of steel, and the handles are generally made from wood, plastic, steel or aluminum. The user holds the gripper in one hand and squeezes the two handles together until they touch. Once touched, the handles are releaed and the movement is repeated. Variations of this basic movement include negatives [see below], and a variety of partial movements. For example, if the strength of the gripper is beyond that of the user, the user might apply maximum force, moving the handles as far as possible, even if the handle cannot be made to touch. Another partial movement involves using two hands to squeeze the handles within approximately 19mm (3/4 inch) of each other, releasing one hand and then using the other hand to make the handles of the geipper touch each other. Negatives involves starting the grippers.

2.2.5.2  Cutting Arm

 The arm may be given a maximum number of degree of freedom in order to enable required object manipulation. Ideally a five degree of freedom arm would be perfect, but a minimum of three would be sufficient. One for shoulder movement, one for elbow movement, one for gripper movement. Three of these servo motor are located near the centre of the multi rotor copter the aerial based system is designed to add versatility to the bomb refusals squad. This enables them to be prepared for any sort of situation that their everyday job might throw at them. This is a system that is capable of identifying bombs by givingthe bomb squad an aerial view. It is designed to quickly access the bomb and perform necessary bomb manipulation in order to diffuse  the bomb. The drone is going to acts as a carrier of the robotic arm. And the arm in other hand is designed using four bar mechanism to have a minimum effect on the stability of the drone. The arm can be attaching the arm at the bottom gives an added advantage to manipulated the bomb while it hovers over it. The defusing unit is the arm and the drone is designed to handle  the vibrations caused by the operation of the arm. The stability of the drone is controlled by the sensors in the flight controller like the Gyroscope,Accelerometer and GPS sensors on board in the flight controller. This would make a valuable addition to the arsenal of the bomb squad. The design and development of this kind of aerial based bomb refusals system is just the beginning. Once development of this kind of aerial based bomb refusals system is just the beginning. Once developed and properly implemented, this will pave the way for more advanced system which employ cutting edge technology to enhance bomb refusals. By proper improvements in sensors and processors, the analysis of incoming transmitter data from the controller as well as the data that is obtained from on board sensors can be done, for effective flight and to maintain the stability. Advancements in branches of mathematics such as control theory enable us to design a drone whose flight is extremely stable under all sorts of conditions.

2.2.6 Jumper Wire

            Jumper wire are extremely handy component to have on hand, especially when prototyping. Jumper wire is simply wires that have connector pins at each end, allowing them to be used to connect two points to each other without soldering. Jumper wires are typically used with breadboards and other prototyping tools in order to make it easy to change a circuit as needed. In fact, it doesn’t get much more basic than jumper wires. Though jumper wires come in a variety of colors, the colors don’t actually mean anything. This means that a red jumper wires is technically the same as black one. But the colors can be used to our advantage in order to differentiate between types of connections, such as ground power. Jumper wire typically come in three versions; male-to-male, male-to-female, female-to-female. The difference between each is in the end point of the wire. Male ends have a pin protruding and can plug into things, while female ends do not and are used to plug things into. Male-to-male jumper wires are the most common and what we likely will use most often. When connecting two ports on a breadboard, a male-to-male wire is what we’ll need.

2.2.7 Wheel

            A differential wheeled robot is a mobile robot whose movement is based on two separately driven wheels placed on either side of the robot body. It can change its direction by varying the relative rate of rotation of its wheels and hence does not require an additional steering motion. To balance the robot, additional wheels or casters may be added. More stable than the four wheel version since the center of gravity has to remain inside  the rectangle formed by the four wheel instead of a triangle. This leaves a larger useful space. Still it’s advisable to keep the center of gravity to the middle of the rectangle as this is the most stable configuration, especially when taking sharp turns or moving over a non-level surface.

             This kind of robot uses 2 pairs of powered wheels. Each pair (connected by a line) turn in the same direction. The trickly part of this kind of propulsion is getting all the wheels to turn with the same speed. If the wheels in a pair aren’t running with the same speed, the slower one will slip (in efficient). If the pairs don’t run at the same speed the robot won’t be able to drive straight. A good design will have to incorporate some form of car like steering. This method allows the robot to turn in the same way a car does. This is a far harder method to build and makes dead reckoning much harder as well. This system does have an advantage over previous methods when our robot is powered by a combustion engine. It only needs one motor (and a servo for steering of course). The previous method would require either 2 motors or a complicated gearbox, since they require 2 output axles with independent speed and direction of rotation.

             If both the wheels are driven in the same direction and speed, the robot will go in a straight line. If both wheels are turn with equal speed in opposite directions, as in clear form the diagram shown, the robot will rotate about the central point of the axis. Otherwise, depending on the speed of rotation and its direction, the center of rotation may fall anywhere on the line define by the two contact points of the tires. While the robot is travelling in a straight line, the center of rotation is an infinite distance from the robot. Since the direction of the robot is dependent on the rate and direction of rotation of the two driven wheels, these quantities should be sensed and controlled precisely. A differential steered robot is similar to the differential gears used in automobiles in that both the wheels can have different rates of rotations, but unlike the differential gearing system, a differential steered system will have both the wheel powered. Differential wheeled robots are use extensively in robotics, since there motion is easy to program and can be well controlled. Vertually all consumer robots on the market today use differential steering primarily for its low cost and simplicity.

2.2.8 Switch

            An electrical switch is any device used to interrupt the flow of electrons in a circuit. Switches are essentially binary devices: they are either completely on (“closed”) or completely off (“open”). There are many different types of switches. Learning the functions of switch-based circuits at the same time that we learn about solid – state logic gates makes both topics easier  to grasp, and sets the stage for an enhanced learning experience in Boolean algebra, the mathematics behind digital logic circuits.

Toggle Switch

            In electronics engineering, a switch is an electrical component that can “make” or “break” an electrical circuit, interrupting the current or diverting it from one conductor to another. The mechanism of a switch removes or restores the conducting path in a circuit when it is operated. It may operated manually, for example, a light switch or a keyboard button, may be operated by a moving object such as a door, or may be operated by some sensing element for pressure, temperature or flow. A switch will have one or more sets of contacts, which may operated simultaneously, sequentially, or alternately. Switches in high – powered  circuits must operated rapidly to prevent destructive arcing, and may include special features assist in rapidly interrupting of heavy circuit. Multiple form of actuators are used for operation by hand or to sense position, level, temperature or flow. Special types are use, for example, for control of machinery, to reverse electric motors, or to sense liquid level. Many specialized forms exist. A common use is control of lighting, where multiple switches may be wired into one circuit to allow to convenient control of light features

.

2.2.9 Bluetooth Module

Bluetooth Communication is a 2.4GHz frequency based RF Communication with a range of approximately 10 meters. It is one of the most popular and most frequently used low range communication for data transfer, audio systems, handsfree, computer peripherals etc.

HC-05 Bluetooth Module is a simple Wireless Communication device based on the Bluetooth Protocol. This module is based on BC417 Single Chip Bluetooth IC that is compliant with Bluetooth v2.0 standard and with support for both UART and USB interfaces.

Generally, the HC-05 Bluetooth Module, or the HC-05 Sub Module, to be precise, comes with the BC417 IC along with a flash memory. Such Modules come as surface mount board and several third-party manufacturers use these board to build a more complete system with necessary pins and components.

The following image shows one such HC-05 Bluetooth Sub Module (the green board mounted on the blue board) being used as a part of a complete Bluetooth Module.

Pins of HC-05 Bluetooth Module

The HC-05 Module supports for UART, USB as well as SPI communication and depending on the application, necessary pins can be used. In my case, the board uses the UART communication.

Coming to the pins of the Bluetooth Module, generally, four pins are sufficient for successfully enabling a wireless communication link but the modules produced now-a-days come with six pins namely: VCC, GND, TX, RX, EN and STATE.Image below shows the pins and other components on a typical HC-05 Bluetooth Module.

An important point to remember is the HC-05 Bluetooth Module works on a logic level of 3.3V. Hence, a 3.3V Regulator is used on the board.

NOTE: The button present on the board is used to configure the Bluetooth Module in AT Command Mode. This part of the Module is not discussed in this project.

Pin Description

• EN: It is the enable pin. When this pin is floating or connected to 3.3V, the module is enabled. If this pin is connected to GND, the module is disabled.
• +5V: This is the supply pin for connecting +5V. As the Module has on-board 3.3V regulator, you can provide +5V supply.
• GND: It is the ground pin.
• TX: It is the Transmitter pin of the UART Communication.
• RX: It is the Receive Pin of UART.
• STATE: This is a status indicator pin. This pin goes LOW when the module is not connected to any device. When the module is paired with any device, this pin goes HIGH.

NOTE: The on-board LED is used to indicate the status of the connection. When the module is not paired, the LED blinks or flashes repeatedly. Once the module is paired, the LED blinks at a constant delay of 2 seconds.

Modes of Operation

The HC-05 Bluetooth Module can be configured in two modes of operation: Command Mode and Data Mode.

In Command Mode, you can communicate with the Bluetooth module through AT Commands for configuring various settings and parameters of the Module like get the firmware information, change UART Baud Rate, change module name, set it as either Master or slave etc.  An important point about HC-05 Module is that it can be configured as Master or Slave in a communication pair. In order to select either of the modes, you need to activate the Command Mode and sent appropriate AT Commands.

Coming to the Data Mode, in this mode, the module is used for communicating with other Bluetooth device i.e. data transfer happens in this mode.

Default Settings of HC-05 Bluetooth Module

The following is a list of few of the default settings of the HC-05 Bluetooth Module.

• Name: HC-05
• Password: 1234 (or 0000)
• Type: Slave
• Mode: Data
• Baud Rate: 9600 with 8 data bits, no parity and 1 stop bit

SOFTWARE DESCRIPTION

3.1 Arduino IDE         

• Arduino IDE is an open source software that is mainly used for writing and compiling the code into the Arduino Module.

• It is an official Arduino software, making code compilation too easy that even a common person with no prior technical knowledge can get their feet wet with the learning process.
• It is easily available for operating systems like MAC, Windows, Linux and runs on the Java Platform that comes with inbuilt functions and commands that play a vital role for debugging, editing and compiling the code in the environment.
• A range of Arduino modules available including Arduino Uno, Arduino Mega, Arduino  Leonardo, Arduino Micro and many more.
• Each of them contains a microcontroller on the board that is actually programmed and accepts the information in the form of code.
• The main code, also known as a sketch, created on the IDE platform will ultimately generate a Hex File which is then transferred and uploaded in the controller on the board.
• The IDE environment mainly contains two basic parts: Editor and Compiler where former is used for writing the required code and later is used for compiling and uploading the code into the given Arduino Module.
•  This environment supports both C and C++ languages.

Software

The program code written for Arduino is known as a sketch. The software used for developing such sketches for an Arduino is commonly known as the Arduino IDE. This IDE contains the following parts in it:

Text editor:.This is where the simplified code can be written using a simplified version of C++ programming language.

Message Area:It displays error and also gives a feedback on saving and exporting the code.

Text:The console displays text output by the Arduino environment including complete error message and other information.

Console Toolbar: This toolbar contains various buttons like Verify, Upload, New, Open, Save and Serial Monitor. On the button right hand corner of the window there displays the development board and the serial port in use.

3.2  Proteus

The Proteus Design Suite is a proprietary software tool suite used primarily for electronics design automation. The software is used mainly by electronic design engineers and technicians to create schematics and electronic prints for manufacturing printed circuit board.

It was developed in Yorkshire, England by Lab center Electronics Ltd and is available in English, French, Spanish and Chinese languages.

BLOCK DIAGRAM

CIRCUIT DIAGRAM AND OPERATION

5.1 CIRCUIT DIAGRAM

Operation

The basic function of android controlled military spying and bomb disposal robot is done by its joints. Joints are analogous to human joints and are used to join the two consecutive rigid bodies in the robot. They can be rotary  joint or linear joint. To add a joint to any link of a robot, we need to know about the degrees of freedom and degrees of movement for that body part. Degrees of freedom implement the linear and rotational movement of the bodies and degrees of movement imply the number of axis the body can move.

A wireless bomb disposal robot consists of two rigid bodies on a moving base, connected together with rotary joint. A rotary joint is a one which provides rotation in 90 degrees around any one of the axis.

• The bottom or the base is attached with wheels which provide linear movement.
• The first rigid body is fixed and supports the second rigid body to which the end effectors are provided.
• The second rigid body is provided with movement in all 3 axis and has 3 degrees of freedom. It is connected to the first body with a rotational joint.
• The end effectors should accommodate all 6 degrees of freedom, in order to reach all side of the component, to take up position to any height.

On a whole, the basic android controlled military spying and bomb disposal robot works as follows:

• The wheels underneath the base help to the robot to move the robot to the desired location.
• The rigid body supporting the end effectors bends or straightens up to reach the position where the object is placed.
• The end effectors pick up the object with a strong grip and the cutter cuts to that object.

A android controlled military spying and bomb disposal robot can be controlled by controlling the movement of its end effectors. However the most effective way is using motors to provide the required motion. The motors have to be controlled in order to provide required motion to the robot and the end effectors.

This robot will be controlled through the android phone. The connection between robot and phone is wireless by using Bluetooth module. When the user sends control signal from the phone connected to this Bluetooth module, this signal goes to the arduino through Bluetooth module. The output of the system is then processed into a signal that can instruct the appropriate module. This module will be a motor of the wheels of the robot or the robotic arm. Then, according to the control signal given by the user this robot will operates. By using the web camera it provides live video stream, so user can control the robot more efficiently.

SOURCE CODE

6.1 Code

#define m1 11 
#define m2 12
#define m3 10
#define m4 9
#define r1 5 
#define r2 4
#define r3 3
#define r4 2
#define s1 6 
#define s2 7
#define s3 8
#define s4 13
void setup()
{
Serial.begin(9600);
pinMode(m1,OUTPUT);
pinMode(m2,OUTPUT);
pinMode(m3,OUTPUT);
pinMode(m4,OUTPUT);
pinMode(r1,OUTPUT);
pinMode(r2,OUTPUT);
pinMode(r3,OUTPUT);
pinMode(r4,OUTPUT);
pinMode(s1,OUTPUT);
pinMode(s2,OUTPUT);
pinMode(s3,OUTPUT);
pinMode(s4,OUTPUT);
}
void loop()
{
while(Serial.available())
  {
    char data = Serial.read();
    if(data=='F')
    {
Serial.println("forward");
forward(); 
    }
    else if (data=='L')
    {
Serial.println("left");
left();
 }  else if (data=='R')
{
 Serial.println("right");
right();
 } else if (data=='B')
 {
Serial.println("backward");
backward();
      }
        else if (data='S')
        {
Serial.println("stop");
stop();
        }
else if (data=='G')
        {
Serial.println("GRIP I");
          Grip I();         
      }
      else if (data=='H')
        {
Serial.println("grip II");
gripII();
      }
else if (data=='C')
        {
Serial.println("grip3");
          grip3();
      }
else if (data=='A')
        {
Serial.println("cut I");
          Cut I();
      }
      else if (data=='E')
        {
Serial.println("cut2");
          cut2();
      }
      else if (data=='I')
        {
Serial.println("cut3");
          cut3();
      }
      else if (data=='J')
        {
Serial.println("cut4");
          cut4();
      } else if (data=='D')
       {
Serial.println("grip4");
          grip4();      
    }

void forward()
{
digitalWrite(m1,HIGH);
digitalWrite(m2,LOW);
digitalWrite(m3,HIGH);
digitalWrite(m4,LOW);
}
void left()
{
digitalWrite(m1,LOW);
digitalWrite(m2,HIGH);
digitalWrite(m3,HIGH);
digitalWrite(m4,LOW);
}
void backward()
{
digitalWrite(m1,LOW);
digitalWrite(m2,HIGH);
digitalWrite(m3,LOW);
digitalWrite(m4,HIGH);
}
void right()
{
digitalWrite(m1,HIGH);
digitalWrite(m2,LOW);
digitalWrite(m3,LOW);
digitalWrite(m4,HIGH);
}
void grip1()
{
digitalWrite(r1,HIGH);
digitalWrite(r2,LOW);
digitalWrite(r3,LOW);
digitalWrite(r4,LOW);
}
void grip2()
{
digitalWrite(r1,LOW);
digitalWrite(r2,HIGH);
digitalWrite(r3,LOW);
digitalWrite(r4,LOW);
}
void grip3()
{
digitalWrite(r1,LOW);
digitalWrite(r2,LOW);
digitalWrite(r3,LOW);
digitalWrite(r4,HIGH);
}
void grip4()
{
digitalWrite(r1,LOW);
digitalWrite(r2,LOW);
digitalWrite(r3,HIGH);
digitalWrite(r4,LOW);
}
void cut1()
{
digitalWrite(s1,HIGH);
digitalWrite(s2,LOW);
digitalWrite(s3,LOW);
digitalWrite(s4,LOW);
}
void cut2()
{
digitalWrite(s1,LOW);
digitalWrite(s2,HIGH);
digitalWrite(s3,LOW);
digitalWrite(s4,LOW);
}
void cut3()
{
digitalWrite(s1,LOW);
digitalWrite(s2,LOW);
digitalWrite(s3,LOW);
digitalWrite(s4,HIGH);
}
void cut4()
{
digitalWrite(s1,LOW);
digitalWrite(s2,LOW);
digitalWrite(s3,HIGH);
digitalWrite(s4,LOW);
}
void stop()
{
digitalWrite(m1,LOW);
digitalWrite(m2,LOW);
digitalWrite(n3,LOW);
digitalWrite(m4,LOW);
digitalWrite(r1,LOW);
digitalWrite(r2,LOW);
digitalWrite(i3,LOW);
digitalWrite(r4,LOW);
digitalWrite(s1,LOW);
digitalWrite(s2,LOW);
digitalWrite(a3,LOW);
digitalWrite(s4,LOW);
}
}

ADVANTAGES & LIMITATIONS

Advantages

1. Provides undetected audio transmission.
2. Simple circuitry and user interface.
3. It has a wireless camera for video feedback so operator can operate more efficiently.
4. Can work in the places where no human can operate such as over land mines because of its light weight.
5. Low power consumption.
6. Since, it is portable , it can be carried to places easily.

Limitations

1. Operable range is limited (about 10m).
2. It requires a trained person to operate.
3. Cannot operate in steep terrains.
4. Operable height is limited (about 1.5 feet above).

 APPLICATIONS

1. It is used for spying and diffusing the bomb.
2. It can be used by: police: in hostage situations.
3. Military: For reconnaissance missions.
4. Fire: To provide video feedback of the site for analysis.
5. Geological surveys for e.g. Caves
6. It can be used in wildlife conservation centers to monitor animals using its live video stream.
7. It can be used to lift light weight medicine packages and other necessary goods in emergency cases using gripper.  

 FUTURE IMPROVEMENTS

1. Removable Gripper/Multi-gripper robotic arm:- The gripper attached to the robotic arm is fixed at the movement that is, it will only work with the specific shaped of objects. Placing the gripper that can be removed and replaced by another gripper can solve this problem or multi gripper robotic arm can be developed with more than 2 types of gripper for different types of material and for and different shaped of objects.

• Step climbing mechanism:- Step climbing mechanism is used for using the staircase which will help the user to move from one floor to another.

• Artificial intelligence:-  At present the robot does not have the capacity to make decision on its own that is there is no built in artificial intelligence in it. Therefore the working is based purely on the decision made by the end user of the robotic control application. Therefore artificial intelligence may be provided to the robot for making the process of decision-making much quicker and reliable.

• Wide operable range:- in the present robot it has limited operable range. So, this limitation can be improved in future.

• With simple modifications in the wheel segment, it can be used in marine applications for monitoring and rescue purpose.

 PROBLEM FORMULATION

We face a lot of problems while creating this project. The first problem was that we did not get the goods of the project here in Nepal. Then we will go to India to bring the goods of the project. We did not get all the stuff like that cutting arm and web camera. Then we bought gripper arm in which we put one cutting scissor in gripper arm. Then problem is that our DC motor and motor driver broke. Then we brought again the DC motor and motor driver. Due to these problems this project consume more time.

CONCLUCSION

The wireless Bomb Disposal Robot has been designed in such a way that it can cater to the needs of the bomb disposal squad, the military, the police and also for the personnel who handle radioactive materials. It has countless applications and can be used in different environments and scenarios. For instance, at one place it can be used by the bomb disposal squad, why at another instance it can be used for handling mines. While another application can be provide up to date information in a hostage situation.

NOTE:

THIS PROJECT IS DONE BY:

Sunil Neupane
Ruchi Kumari
Sneha Shubham
Samika Bhattarai
Suman Rajbanshi

Under the guidance of:
Er. Rabin Poudel