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Cellphone Operated land rover

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					                                   A
                        Project Report on



                                Submitted to
            Ra jas tha n T echnical Univ ersity, Ko ta
In Partial Fulfillment of the requirement for the award of the degree of
                     Bachelor of Technology
                                   In
            “Electronics & Communication Engineering”




        Modi Institute of Technology
            Nayag aon, Raw atbha ta Road, Ko ta
                                        ABSTRACT


In this project the robot, is controlled by a mobile phone that makes call to the mobile phone
attached to the robot in the course of the call, if any button is pressed control corresponding to
the button pressed is heard at the other end of the call. This tone is called dual tone multi
frequency tome (DTMF) robot receives this DTMF tone with the help of phone stacked in the
robot.
The received tone is processed by the atmega16 microcontroller with the help of DTMF decoder
HT9170 the decoder decodes the DTMF tone in to its equivalent binary digit and this binary
number is send to the microcontroller, the microcontroller is preprogrammed to take a decision
for any give input and outputs its decision to motor drivers in order to drive the motors for
forward or backward motion or a turn. The mobile that makes a call to the mobile phone stacked
in the robot acts as a remote.
So this simple robotic project does not require the construction of receiver and transmitter units.
DTMF signaling is used for telephone signaling over the line in the voice-frequency band to the
call switching centre. The version of DTMF used for telephone tone dialing is known as ‘Touch-
Tone.’
DTMF assigns a specific frequency (consisting of two separate tones) to each key So that it can
easily be identified by the electronic circuit. The signal generated by the DTMF encoder is a
direct algebraic summation, in real time, of the amplitudes of two sine (cosine) waves of
different frequencies.
                                                                            CHAPTER 1


                                   INTRODUCTION


Robotics is an interesting field where every engineer can showcase his creative and technical
skills. Pleasing aspect of robotics is that a robot can be made indigenously by anyone. In this
competitive world there is need for every enthusiastic, amateur to professional, to make a simple
robot having innovated applications and with robust control.

Mobile phones today became an essential entity for one and all and so, for any mobile based
application there great reception. In this scenario making a mobile phone operated land rover is a
good idea. Conventionally wireless controlled robots utilize RF circuits, which had limitations
like limited range, limited frequency ranges and controls. But a mobile phone controlled robot
can hold up these limitations. It has a robust control, unlimited range (coverage area of the
service provided), no fear of interfering with other controllers and we can have as much as
12controls.

Although the appearance and capabilities of robots vary vastly, all robots share the features of a
mechanical, moveable structure under some form of control. This control of robot involves three
distinct phases: perception, processing and action. In common preceptors are sensors mounted on
the robot, processing is done by on-board microcontroller or processor and task (action) is
performed using motors or with some other actuators.
                                                                             CHAPTER 2


                                TECHNOLOGY USED


2.1Dual-Tone Multi-Frequency (DTMF)


Dual-tone multi-frequency (DTMF) signaling is used for telecommunication signaling over
analog telephone lines in the voice-frequency band between telephone handsets and other
communications devices and the switching center. The version of DTMF used for telephone tone
dialing is known by the trademarked term Touch-Tone, and is standardized by ITU-T. It is also
known in the UK as MF4. Other multi-frequency systems are used for signaling internal to the
telephone network.

As a method of in-band signaling, DTMF tones were also used by cable television broadcasters
to indicate the start and stop times of local commercial insertion points during station breaks for
the benefit of cable companies. Until better out-of-band signaling equipment was developed in
the 1990s, fast, unacknowledged , and loud DTMF tone sequences could be heard during the
commercial breaks of cable channels in the US and elsewhere.




2.1.1Telephone keypad



The contemporary keypad is laid out in a3x4 grid, although the original DTMF keypad had an
additional column for four now-defunct menu selector keys. When used to dial a telephone
number, pressing a single key produce a pitch consisting of two simultaneous pure tones
sinusoidal frequencies. The row in which the key appears determines the low frequency, and the
column determines the high frequency. For e.g., pressing the ‘1’ key will result in a sound
composed of both a 697 and a 1209Hz tone. The original keypads had levers inside, so each
button activated two contacts. Multiple tones are the reason for calling the system multi
frequency. These tones are then decoded by the switching center to determine which key was
pressed.




2.1.2 Tones #, *, A, B, C AND D



The Engineers had envisioned phones being used to access computers, and surveyed a number of
companies to see what they would need for this role. This led to the addition of number sign (#
sometimes called ‘octothorpe’ in this context) and asterisk or “star” (*) keys as well as a group
of keys for menu selection: A, B, C and D. In the end the lettered keys were dropped from most
phones, and it was many years before these keys became widely used for vertical service codes
such as *67 in United States and Canada for suppressing caller ID.




The U.S. military also used the letters, relabeled in their new defunct Autovon phone system.
Here they were used before dialing the phone in order to give some calls priority, cutting in over
existing calls if need be. The idea was to allow important traffic to get through every time. The
levels of priority available were Flash Override (A), Flash (B), Immediate (C), and Priority (D),
with Flash Override being the highest priority.




                                  A DTMF telephone keypad
                                                                                 CHAPTER 3


                          DESIGN AND DEVELOPMENT


The important components of this robot are a DTMF decoder, microcontroller and motor driver.
An HT9170 series DTMF decoder is used here. All types of the HT9170 series use digital
counting techniques to detect and decode all the 16 DTMF tone pairs into a 4-bit code output.
The built-in dial tone rejection circuit eliminates the need of pre-filtering.

When the input signal given at pin 2(IN-) in single-ended input configuration is recognized to be
effective, the correct4-bit decode signal of the DTMF tone is transferred to (pin11) through
(pin14) outputs. The pin11 to pin14 of DTMF decoder are connected to the pins of
microcontroller (pa0 to pa3).The ATmega16 is a low power, 8-bit CMOS microcontroller based
on the AVR enhanced RISC architecture. it provides the following features: 16kb of in-system
programmable flash program memory with read-while-write capabilities, 512 bytes of EEPROM,
1kb SRAM, 32(I\O) lines. Outputs from port pins PD0 through PD3 and PD7 of the
microcontroller are fed to the inputsIN1 through IN4 and enable pins (EN1 and EN2) of motor
driver L293D IC, respectively to drive two geared dc motors. Switch S1 is used for manual reset.

The microcontroller output is not sufficient to drive the dc motors, so current drivers are required
for motor rotation. The L293D is a quad, high-current, half-h driver designed to provide
bidirectional drive currents of upto600mA at voltages from 4.5V to 36V. It makes it easier to
drive the dc motors. The L293D consists of four drivers. Pins IN1 through IN4 and OUT1
through OUT4 are the input and output pins, respectively, of driver 1 through driver 4. Drivers 1
and 2, and driver 3 and 4 are enabled by enable pin 1(EN1) and pin 9 (EN2), respectively.
When enable input EN1 (pin1) is high, drivers 1 and 2 are enabled and the outputs corresponding
to their inputs are active. Similarly, enable input EN2 (pin9) enables drivers 3 and 4 .




TABLE I


Tones and Assignments in a DTMF system



   Frequencies           1209Hz           1336Hz          1477Hz          1633Hz



      697Hz                  1               2               3                A



      770Hz                  4               5               6                B



      852Hz                  7               8               9                C


      941Hz                  *               0               #                D




TABLE II


DTMF Data Output
   Low      High      Digit   OE   D3   D2   D1   D0
group(Hz) group(Hz)

   697      1209       1      H    L    L    L    H

   697      1336       2      H    L    L    H    L

   697      1477       3      H    L    L    H    H

   770      1209       4      H    L    H    L    L

   770      1336       5      H    L    H    L    H

   770      1477       6      H    L    H    H    L

   852      1209       7      H    L    H    H    H

   852      1336       8      H    H    L    L    L

   852      1477       9      H    H    L    L    H

   941      1336       0      H    H    L    H    L

   941      1209       *      H    H    L    H    H

   941      1477       #      H    H    H    L    L

   697      1633       A      H    H    H    L    H

   770      1633       B      H    H    H    H    L

   852      1633       C      H    H    H    H    H

   941      1633       D      H    L    L    L    L

  _______   ______    ANY     L    Z    Z    Z    Z
TABLE III


Actions Performed Corresponding to the keys pressed


  Number      Output of    Input to the        Action performed
 pressed by   HT9170      microcontroller
    user

                0x02          0xFD              Forward motion

     2        00000010      11111101

                0x0F          0xFB                 Left turn

     4        00000100      11111011         Right motor forwarded

                                            Left motor back warded

                0x06           0xF9               Right turn

     6        00000110      11111001        Right motor back warded

                                             Left motor forwarded

                0x08           0xF7            Backward motion

     8        00001000      11110111

                0x05          0xFA                   Stop

     5        00000101      11111010
3.1 Block Diagram




Figure 1 Block Diagram of CellPhone Controlled Robot


Block Diagram Description
The following are the main components in block diagram


Phone unit
DTMF decoder
Microcontroller
Motor driver
       Phone unit is to give the desired control to the decoder part.


       DTMF decoder is to decode the input signal to corresponding binary.


       Microcontroller converts the incoming binary to corresponding codes to require driving
       the motor driver.


       Motor driver amplify the input signal for driving motor




3.2 Circuit Diagram




Figure 2 Circuit Diagram of CellPhone Controlled Robot
3.3 Components Used


Semiconductors:
HT9170 DTMF decoder
ATMEGA 16 microcontroller
L293D motor driver
74LS04 hex inverting gate


Resistors (all ¼-watt, ±5% carbon):
100-kilo-ohm
300-kilo-ohm
10-kilo-ohm
100-ohm
220-ohm


Capacitors:
0.1mF ceramic disk
20pF ceramic disk
33pFceramic disk


Miscellaneous:
3.57MHz crystal
12MHz crystal
SW - Push-to-on switch
M1, M2 - 200-rpm geared DC motor
Bt1, Bt2 - 9V battery
TV Transmitter and Voltage regulator 7805
3.4 Components Details


        HT9170 DTMF Decoder


DTMF Receiver



Features:


        Operating voltage: 2.5V~5.5V
        Minimal external components
        No external filter is required
        Low standby current (on power down mode)
        Excellent performance
        Tristate data output for _C interface
        3.58MHz crystal or ceramic resonator
        1633Hz can be inhibited by the INH pin


General Description:


The HT9170 series are Dual Tone Multi Frequency (DTMF) receivers integrated with digital
decoder and band split filter functions. The HT9170B and HT9170D types supply power-down
mode and inhibit mode operations. All types of the HT9170 series use digital counting
techniques to detect and decode all the 16 DTMF tone pairs into a 4-bit code output. Highly
accurate switched capacitor filters are employed to divide tone (DTMF) signals into low and
high group signals. A built-in dial tone rejection circuit is provided to eliminate the need for pre-
filtering.
Block Diagram:




Figure 3 Block Diagram of DTMF Receiver




Functional Description:


Overview:


The HT9170 series tone decoders consist of three band pass filters and two digital decode
circuits to convert a tone (DTMF) signal into digital code output. An operational amplifier is
built-in to adjust the input signal (refer to Figure 2).
Figure 4 Input operation for amplifier application circuits

The pre-filter is a band rejection filter which reduces the dialing tone from 350Hz to 400Hz. The
low group filter filters low group frequency signal output whereas the high group filter filters
high group frequency signal output. Each filter output is followed by a zero-crossing detector
with hysteresis. When each signal amplitude at the output exceeds the specified level, it is
transferred to full swing logic signal. When input signals are recognized to be effective, DV
becomes high, and the correct tone code (DTMF) digit is transferred.
Steering control circuit:


The steering control circuit is used for measuring the effective signal duration and for protecting
against drop out of valid signals. It employs the analog delay by external RC time-constant
controlled by EST.
The timing is shown in Figure 3. The EST pin is normally low and draws the RT/GT pin to keep
low through discharge of external RC. When a valid tone input is detected, EST goes high to
charge RT/GT through RC.
When the voltage of RT/GT changes from 0 to VTRT (2.35V for 5V supply), the input signal is
effective, and the correct code will be created by the code detector. After D0~D3 are completely
latched, DV output becomes high. When the voltage of RT/GT falls down from VDD to VTRT
(i.e.., when there is no input tone), DV output becomes low, and D0~D3 keeps data until a next
valid tone input is produced.
By selecting adequate external RC value, the minimum acceptable input tone duration (tACC)
and the minimum acceptable inter-tone rejection (tIR) can be set. External components (R, C) are
chosen by the formula (refer to Figure 5.):
tACC=tDP+tGTP;
tIR=tDA+tGTA;
where tACC: Tone duration acceptable time
       tDP: EST output delay time (_L__H_)
       tGTP: Tone present time
       tIR: Inter-digit pause rejection time
       tDA: EST output delay time (_H__L_)
       tGTA: Tone absent time
Application Circuits:




     Figure 5 Application Circuits of DTMF Receiver
      ATMEGA 16 microcontroller


Features:

  •   High-performance, Low-power AVR® 8-bit Microcontroller
  •   Advanced RISC Architecture
         –   131 Powerful Instructions – Most Single-clock Cycle Execution
         –   32 x 8 General Purpose Working Registers
         –   Fully Static Operation
         –   Up to 16 MIPS Throughput at 16 MHz
         –   On-chip 2-cycle Multiplier
  •   Nonvolatile Program and Data Memories
         –   16K Bytes of In-System Self-Programmable Flash
                    Endurance: 10,000 Write/Erase Cycles
         –   Optional Boot Code Section with Independent Lock Bits
                    In-System Programming by On-chip Boot Program
                    True Read-While-Write Operation
         –   512 Bytes EEPROM
                    Endurance: 100,000 Write/Erase Cycles
         –   1K Byte Internal SRAM
         –   Programming Lock for Software Security
  •   JTAG (IEEE std. 1149.1 Compliant) Interface
         –   Boundary-scan Capabilities According to the JTAG Standard
         –   Extensive On-chip Debug Support
         –   Programming of Flash, EEPROM, Fuses, and Lock Bits through the JTAG
             Interface
         –
  •   Peripheral Features
         –   Two 8-bit Timer/Counters with Separate Prescalers and Compare Modes
         –   One 16-bit Timer/Counter with Separate Prescaler, Compare Mode, and Capture
         –
•   Mode
       –   Real Time Counter with Separate Oscillator
       –   Four PWM Channels
       –   8-channel, 10-bit ADC
•   8 Single-ended Channels
•   7 Differential Channels in TQFP Package Only
•   2 Differential Channels with Programmable Gain at 1x, 10x, or 200x
       –   Byte-oriented Two-wire Serial Interface
       –   Programmable Serial USART
       –   Master/Slave SPI Serial Interface
       –   Programmable Watchdog Timer with Separate On-chip Oscillator
       –   On-chip Analog Comparator
•   Special Microcontroller Features
       –   Power-on Reset and Programmable Brown-out Detection
       –   Internal Calibrated RC Oscillator
       –   External and Internal Interrupt Sources
       –   Six Sleep Modes: Idle, ADC Noise Reduction, Power-save, Power-down, Standby
•   and Extended Standby
•   I/O and Packages
       –   32 Programmable I/O Lines
       –   40-pin PDIP, 44-lead TQFP, and 44-pad MLF
•   Operating Voltages
       –   4.5 - 5.5V for ATmega16


•   Speed Grades
       –   0 - 16 MHz for ATmega16
Block Diagram:




Figure 6 Block Diagram of ATMEGA 16 microcontroller
AVR CPU Core:

Introduction:

This section discusses the AVR core architecture in general. The main function of the CPU core
is to ensure correct program execution. The CPU must therefore be able to access memories,
perform calculations, control peripherals, and handle interrupts.


Architectural Overview:
Block Diagram of the AVR MCU Architecture:




               Figure 7 Architectural Overview of ATMEGA 16 microcontrollers
In order to maximize performance and parallelism, the AVR uses a Harvard architecture – with
separate memories and buses for program and data. Instructions in the program memory are
executed with a single level pipelining. While one instruction is being executed, the next
instruction is pre-fetched from the program memory. This concept enables instructions to be
executed in every clock cycle. The program memory is In- System Reprogrammable Flash
memory.
The fast-access Register file contains 32 x 8-bit general purpose working registers with a single
clock cycle access time. This allows single-cycle Arithmetic Logic Unit (ALU) operation. In a
typical ALU operation, two operands are output from the Register file, the operation is executed,
and the result is stored back in the Register file – in one clock cycle.
Six of the 32 registers can be used as three 16-bit indirect address register pointers for Data
Space addressing – enabling efficient address calculations. One of the these address pointers can
also be used as an address pointer for look up tables in Flash Program memory. These added
function registers are the 16-bit X-, Y-, and Z-register, described later in this section.
The ALU supports arithmetic and logic operations between registers or between a constant and a
register. Single register operations can also be executed in the ALU. After an arithmetic
operation, the Status Register is updated to reflect information about the result of the operation.
Program flow is provided by conditional and unconditional jump and call instructions, able to
directly address the whole address space. Most AVR instructions have a single 16-bit word
format. Every program memory address contains a 16- or 32-bit instruction.
Program Flash memory space is divided in two sections, the Boot program section and the
Application Program section. Both sections have dedicated Lock bits for write and read/write
protection. The SPM instruction that writes into the Application Flash memory section must
reside in the Boot Program section.
During interrupts and subroutine calls, the return address program counter (PC) is stored on the
Stack. The Stack is effectively allocated in the general data SRAM, and consequently the stack
size is only limited by the total SRAM size and the usage of the SRAM. All user programs must
initialize the SP in the reset routine (before subroutines or interrupts are executed). The Stack
Pointer SP is read/write accessible in the I/O space. The data SRAM can easily be accessed
through the five different addressing modes supported in the AVR architecture.
The memory spaces in the AVR architecture are all linear and regular memory maps.
A flexible interrupt module has its control registers in the I/O space with an additional global
interrupt enable bit in the Status Register. All interrupts have a separate interrupt vector in the
interrupt vector table. The interrupts have priority in accordance with their interrupt vector
position. The lower the interrupt vector address, the higher the priority.
The I/O memory space contains 64 addresses for CPU peripheral functions as Control Registers,
SPI, and other I/O functions. The I/O Memory can be accessed directly, or as the Data Space
locations following those of the Register file, $20 - $5F.




       L293D Motor Driver IC


FEATURES:
       Featuring Unitrode L293 and L293D Products Now From Texas Instruments
       Wide Supply-Voltage Range: 4.5 V to 36 V
       Separate Input-Logic Supply
       Internal ESD Protection
       Thermal Shutdown
       High-Noise-Immunity Inputs
       Functional Replacements for SGS L293 and SGS L293D
       Output Current 1 A Per Channel(600 mA for L293D)
       Peak Output Current 2 A Per Channel(1.2 A for L293D)
       Output Clamp Diodes for Inductive
       Transient Suppression (L293D)
Description:

The L293 and L293D are quadruple high-current half-H drivers. The L293 is designed to provide
Bidirectional drive currents of up to 1 A at voltages from 4.5 V to 36 V. The L293D is designed
to provide bidirectional drive currents of up to 600-mA at voltages from 4.5 V to 36 V. Both
devices are designed to drive inductive loads such as relays, solenoids, dc and bipolar stepping
motors, as well as other high-current/high-voltage loads in positive-supply applications.


All inputs are TTL compatible. Each output is a complete totem-pole drive circuit, with a
Darlington transistor sink and a pseudo-Darlington source. Drivers are enabled in pairs, with
drivers 1 and 2 enabled by 1,2EN and drivers 3 and 4 enabled by 3,4EN. When an enable input is
high, the associated drivers are enabled and their outputs are active and in phase with their
inputs. When the enable input is low, those drivers are disabled and their outputs are off and in
the high-impedance state. With the proper data inputs, each pair of drivers forms a full-H (or
bridge) reversible drive suitable for solenoid or motor applications.
       On the L293, external high-speed output clamp diodes should be used for inductive
       transient suppression.
       A VCC1 terminal, separate from VCC2, is provided for the logic inputs to minimize
       device power dissipation.
       The L293and L293D is characterized for operation from 0°C to 70°C.




                       +5V




                                                     +9V

                                    16      8
                                2               3
                 A
                                                           MOTOR
                  B             7
                                    L293D IC 6

                  C             10
                                                11

                                15                          MOTOR
                  D
                                                14

                                   4     5 12 13




                 GND




Figure 8 Motor Driver Circuit using in Cellphone Controlled Robot
Block Diagram:




     Figure 9 Block Diagram of L293D Motor Driver IC
APPLICATION INFORMATION:




              Figure 10 Two-Phase Motor Driver (L293D)
       SN74LS04

This device contains six independent gates each of which performs the logic INVERT function.




Function Table:
       Voltage Regulator 7805
       (3-Terminal 1A Positive Voltage Regulator)


Description:
The KA78XX/KA78XXA series of three-terminal positive regulator are available in the TO
220/D-PAK package and with several fixed output voltages, making them useful in a wide range
of applications. Each type employs internal current limiting, thermal shut down and safe
operating area protection, making it essentially indestructible. If adequate heat sinking is
provided, they can deliver over 1A output current. Although designed primarily as fixed voltage
regulators, these devices can be used with external components to obtain adjustable voltages and
currents.
Internal Block Diagram:




Figure 11 Internal Block Diagram of voltage regulator
An actual-size, single-side PCB for cellphone controlled robot and its component layout in fig.




  Figure 12 CellPhone Controlled Robot and its component PCB layout
3.5 Circuit Diagram Description (Flow Chart)
                                                                              CHAPTER 4


                      WORKING AND CONSTRUCTION


4.1 Working


In order to control the robot, you need to make a call to the cell phone attached to the robot
(through headphone) from any phone, which sends DTMF tunes on pressing the numeric
buttons. The cell phone in the robot is kept in 'auto answer' mode. (if the mobile does not have
the auto answering facility ,receive the call by 'OK' key on the rover connected mobile and then
made it in hands-free mode.) so after a ring, the cell phone accepts the call. Now you may press
any button on your mobile to perform actions as listed in the table. The DTMF tones thus
produced are received by the cell phone in the robot. These tones are fed to the circuit by headset
of the cell phone. The HT9170 decodes the received tone and sends the equivalent binary
number to the microcontroller. According to the program in the microcontroller, the robot starts
moving, When you press key '2' (binary equivalent 00000010) on your mobile phone, the
microcontroller outputs '10001001' binary equivalent. Port pins PD0, PD3 and PD7 are high. The
high output at PD7 of the microcontroller drives the motor driver (L293D) port pins PD0 and
PD3 drive motors M1 and M2 in forward direction( as per table ).Similarly, motors M1 and M2
move for left turn, right turn, backward motion and stop condition as per (table ).
4.2 Construction


When constructing any robot, one major mechanical constraint is the number of motors being
used. You can have either a two-wheel drive or a four-wheel drive. Though four-wheel drive is
more complex than two-wheel drive, it provides more torque and good control.
Top view of a four-wheel-drive land rover is shown in Fig.3. The chassis used in this model is a
10 x 18 cm2 sheet made up of par ax. Motors are fixed to the bottom of this sheet and the circuit
is affixed firmly on top of the sheet. A cell phone is also mounted on the sheet as shown in the
picture.
In the four-wheel drive system, the two motors on a side are controlled in parallel. So a single
L293D driver IC can drive the rover. For this robot, beads affixed with glue act as support
wheels.


FRONT VIEW OF HARDWARE




Figure 13 Front View of Hardware
TOP VIEW OF HARDWARE




Figure 14 Top View of Hardware
                                                                            CHAPTER 5



                        SOFTWARE / TOOL ENVIRONMENT

The software is written in ‘C’ language and compiled using Code Vision AVR ‘C’ compiler. The
source program is converted into hex code by the compiler. Burn this hex code into ATmega16
AVR microcontroller.
The source program is well commented and easy to understand. First include the register name
defined specifically for ATmega16 and also declare the variable. Set port A as the input and port
D as the output. The program will run forever by using ‘while’ loop. Under ‘while’ loop, read
port A and test the received input using ‘switch’ statement. The corresponding data will output at
port D after testing of the received data.


5.1 Programme Code


#include <mega16.h>
Void main (void)
       {
           Unsigned int k, h;
           DDRA=0x00;
           DDRD=0XFF;
 While (1)
   {
           k =~PINA;
           h=k & 0x0F;
   Switch (h)
           {
           Case 0x02:
{
PORTD=0x89;
Break;
}
Case 0x08:
{
PORTD=0x86;
Break;
}
Case 0x04:
{
PORTD=0x85;
Break;
}
Case 0x06:
{
PORTD=0x8A;
Break;
}
Case 0x05:
{
PORTD=0x00;
Break;
}
}
}
}
5.2 Hex Code of the Programme


: 100000000C942B000C9400000C9400000C94000045
: 100010000C9400000C9400000C9400000C94000060
: 100020000C9400000C9400000C9400000C94000050
: 100030000C9400000C9400000C9400000C94000040
: 100040000C9400000C9400000C9400000C94000030
: 100050000C9400000000F894EE27ECBBF1E0FBBF2D
: 10006000EBBFE5BFF8E1F1BDE1BD8DE0A2E0BB274C
: 10007000ED938A95E9F780E094E0A0E6ED9301978F
: 10008000E9F7E4E5F0E085919591009761F0A5919D
: 10009000B59105901590BF01F00105900D92019763
: 1000A000E1F7FB01F0CFEFE5EDBFE4E0EEBFC0E626
: 1000B000D1E00C945B00E0E0EABBEFEFE1BBE9B319
: 1000C000E0950E2F1127F801EF70F0709F01F901F4
: 1000D000E230A0E0FA0711F4E9E817C0E830A0E048
: 1000E000FA0711F4E6E811C0E430A0E0FA0711F4D1
: 1000F000E5E80BC0E630A0E0FA0711F4EAE805C035
: 10010000E530A0E0FA0711F4E0E0E2BBD8CFFFCF82
: 00000001FF
                                                                            CHAPTER 6


                          RESULTS AND DISCUSSION

Cell phone acts as a DTMF generator with tone depending upon key pressed. DTMF decoder i.e.
IC HT9170 decodes the received tone and gives binary equivalent of it to the microcontroller.
The controller is programmed such that appropriate output is given to motor driver IC L293D
which will drive the two DC motors connected to it. The concept used for driving is ‘differential
drive’. So ultimately the two motors rotate according to the key pressed on the keypad of the cell
phone.
                                                                              CHAPTER 7


Applications, Further Improvements & Future Scope


7.1Applications
7.1.1Scientific


Remote control vehicles have a various scientific uses including hazardous environments,
working in the Deep Ocean, and space exploration. The majority of the probes to the other
planets in our solar system have been remote control vehicles, although some of the more recent
ones were partially autonomous. The sophistication of these devices has fueled greater debate on
the need for manned space flights and exploration. The voyager I spacecraft is the first craft of
any kind to leave the solar system. The Martian explorers Spirit and Opportunity have provided
continuous data about the surface of Mars since January 3, 2004.


7.1.2 Military and Law Enforcement


Remote controlled vehicles are used in Law enforcement and military engagements because of
many reasons. The exposures to hazards are mitigated to the person who operates the vehicle
from the location of relative safety. They are used by many police department bomb-squads to
defuse or detonate explosives.


Current Unmanned Aerial Vehicles (UAVs) can hover around possible targets until they are
positively identified before releasing their pay load of weaponry. Backpack sized UAVs will
provide ground troops with over the horizon surveillance capabilities.
7.1.3 Search and Rescue


UAVs play an increased role in search and rescue all over the world. This was demonstrated by
the successful use of UAVs during the 2008 hurricanes that struck Louisiana and Texas in US.


7.1.4 Recreation and Hobby


Small scale remote control vehicles span a wide range in terms of price and sophistication. There
are many types like on-road cars, off-road truck, boats, aero planes and helicopters. Radio-
controlled submarine also exist



7.2 Further Improvements & Future Scope


7.2.1 IR Sensors:


IR sensors can be used to automatically detect and avoid obstacles if the robot goes beyond line
of sight. This avoids damage to the vehicle if we are maneuvering it from a distant place.



7.2.2 Password Protection


Project can be modified in order to password protect the robot so that it can be operated only if
correct password is entered. Either cell phone should be password protected or necessary
modification should be made in the assembly language code. This introduces conditioned access
and increases security to a great extent.
7.2.3 Alarm Phone Dialer


By replacing DTMF Decoder IC HT9170 by a ‘DTMF Transceiver IC’, DTMF tones can be
generated from the robot. So, a project called ‘Alarm Phone Dialer’ can be built which will
generate necessary alarms for something that is desired to be monitored (usually by triggering a
delay). For e.g., a high water alarm, low temperature alarm, opening of back window, garage
door etc.

When the system is activated it will call a number of programmed numbers to let the user know
the alarm has been activated. This would be great to get alerts of alarm conditions from home
when user is at work.



7.2.4 Adding A Camera:


If the current land rover is interfaced with a camera (e.g. a web cam) robot can be driven beyond
line-of-sight and range becomes unlimited as GSM networks have a very large range.




.
                                                                               CHAPTER 8


                                      CONCLUSION


Conventionally, wireless-controlled robots use RF circuits, which have the drawbacks of limited
working range, limited frequency range and limited control. Use of a mobile phone for robotic
control can overcome these limitations. It provides the advantages of robust control, working
range as large as the coverage area of the service provider, no interference with other controllers
and up to twelve controls. Although the appearance and capabilities of robots vary vastly, all
robots share the features of a mechanical, movable structure under some form of control. The
control of robot involves three distinct phases: perception, processing and action. Generally, the
preceptors are sensors mounted on the robot, processing is done by the on-board microcontroller
or processor, and the task (action) is performed using motors or with some other actuators.
                                 REFERENCES



1. Schenker, L(1960), “Pushbutton Calling with a Two-Group Voice-Frequency Code”, The
   Bell system technical journal 39(1): 235-255,ISSN 0005-8580


2. “DTMF Tester, ‘Electronics For You’ Magazine, Edition(June 2003)
    http://www.instructables.com


3. http://en.wikipedia.org/wiki/Passive_infrared_sensor


4. http://www.alldatasheet.com


5. http://www.datasheet4u.com


6. http://www.datasheetcatalog.com
                       APPENDICES


ATmega 16 Microcontroller

Pin Configurations:
Pin Descriptions:

VCC

GND Ground

Port A (PA7… PA0)
Port A serves as the analog inputs to the A/D Converter. Port A also serves as an 8-bit bi
directional I/O port, if the A/D Converter is not used. Port pins can provide internal pull-up
resistors (selected for each bit). The Port A output buffers have symmetrical drive characteristics
with both high sink and source capability. When pins PA0 to PA7 are used as inputs and are
externally pulled low, they will source current if the internal pull-up resistors are activated. The
Port A pins are tri-stated when a reset condition becomes active, even if the clock is not running.


Port B (PB7… PB0)

Port B is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit).
The Port B output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port B pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port B pins are tri-stated when a reset condition becomes active, even
if the clock is not running. Port B also serves the functions of various special features of the
ATmega16.

Port C (PC7… PC0)
Port C is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit). The
Port C output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port C pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port C pins are tri-stated when a reset condition becomes active, even
if the clock is not running. If the JTAG interface is enabled, the pull-up resistors on pins PC5
(TDI), PC3 (TMS) and PC2 (TCK) will be activated even if a reset occurs. Port C also serves the
functions of the JTAG interface and other special features of theATmega16.
Port D (PD7… PD0)
Port D is an 8-bit bi-directional I/O port with internal pull-up resistors (selected for each bit).
The Port D output buffers have symmetrical drive characteristics with both high sink and source
capability. As inputs, Port D pins that are externally pulled low will source current if the pull-up
resistors are activated. The Port D pins are tri-stated when a reset condition becomes active, even
if the clock is not running. Port D also serves the functions of various special features of the
ATmega16.


RESET
Reset Input. A low level on this pin for longer than the minimum pulse length will generate a
reset, even if the clock is not running. The minimum pulse length is Shorter pulses are not
guaranteed to generate a reset.


XTAL1
Input to the inverting Oscillator amplifier and input to the internal clock operating circuit.


XTAL2
Output from the inverting Oscillator amplifier.


AVCC
AVCC is the supply voltage pin for Port A and the A/D Converter. It should be externally
connected to VCC, even if the ADC is not used. If the ADC is used, it should be connected to
VCC through a low-pass filter.



AREF AREF is the analog reference pin for the A/D Converter.
HT9170 DTMF Decoder IC
Pin Assignment:
Pin Description:
Contacts for more Info:-


     Kaushal Singh Kiroula (+91 9166464344)
     Singh.koushal92@gmail.com
     Mohit Sharma

     mohitsetcul@gmail.com (+91 8107772571)
     Mohd. Shahbaz Khan
     Khanshahbaz44@gmail.com (+91 9784243995)

     Kapil Sharma
     Kapil2010sharma@gmail.com (+91 8003535095)

				
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