18-10-2016, 04:14 PM
1459706796-71408003DOORLOCKThroughTelephoneUsingDtmfCOMPLETED.pdf (Size: 1.69 MB / Downloads: 3)
INTRODUCTION
In this age of digital technology, every device and its operation has become
digital based. Now with digital based door lock systems, it is easier to control the
door movement of the car or house. The new automated door lock system does not
need a key to lock or unlock the door of the car or house. This digital door entry
system is in fact controlled by cell-phone which is actually performing the role of
remote over here. The keyless door remote is an electronic circuit based device.
This remote transmits DTMF signals via air to another device of the system
installed in the car door or house door.. The keyless car remote can be operated
from any corner of the world. The working of this locking system is very simple.
You just have to carry the cell phone with yourself and you can control the locks
from anywhere without any problem. It works on the entry number. The owner has
to press that entry number on the cell phone for controlling the locking system. The
entry number is unique in nature and so is the remote device of an automatic
keyless system. You can install a keyless entry system in your house as well as in
your vehicle. Now, a days theft cases are increasing everywhere and the key based
locking system is no longer a safe option. It is quite easy for thieves and robbers to
open the traditional key based doors either with duplicate keys or some other way.
Therefore for safety of your house and vehicle, this system can be installed. With
this system, you will never be in tension of leaving your house and vehicle out of
your supervision. Not only this ,it also help us to move out of some really odd
situations like you locked the door and left and in your absence other members
came back and then they have to wait outside if they were not having key with
themselves.
Motivation
Keyless entry has been a luxury whose availability is confined primarily to
vehicles. The cell phone security system takes this idea of keyless entry and
transforms it into a convenient, versatile security system that utilizes cell phone
technology and the landline telephone network. By taking advantage of caller
identification and dual-tone multi-frequency signaling, the security system has the
ability to introduce two-levels of security. The first level will be decoding the
calling party’s identification information while the second level would consist of
the user attempting a password entry over the phone.. By combining the mobility
of this telecommunication medium with microcontrollers, the system achieves a
secure, convenient, and automated form of security for a place of residence.
1.2 PROBLEM DEFINITION
The cell phone security system is the result of a fusion of a creative idea with an
attempt to motivate change. Even though modern technology has allowed for the
automation of many aspects of domestic lifestyles, from automatic motion sensing
lights to automatic garage door openers, home security has not seen much benefit
from this revolution. Household entry has long been a very manual routine with
little effort to automate the process. Entry into a residence is still primarily limited
to a manual process which involves inserting a key into a bolt and physically
moving the locking-mechanism
1.3 OBJECTIVE OF PROJECT
The fundamental requirements for the cell phone security system remained fixed
throughout the design process. The goal was to design a system which would allow
the user automated and convenient access to their home security system through a
telephone network.
The fundamental objectives of the system include:
1. Correctly decode the DTMF signals from the user.
2. Correctly decode caller identification information from the phone line.
3. Allow the user to automatically lock the entryway.
4. Allow the user to automatically unlock the entryway.
2
1.4 LIMITATIONS OF PROJECT
The cell phone security system aims to change this. The system takes advantage of
the widespread acceptance of cell phones in today’s society in conjunction with the
deep-rooted standards of the landline telephone network to introduce automation
and convenience. The system will allow a user to use their cell phone to place a
call into their home security system. Once the system verifies the caller, the caller
is then allowed to attempt a password entry. Upon successfully entering a
password, the system will automatically unlock the door and grant entrance. This
automation introduces a form of secure, keyless entry into a residence along with
the convenience of a fully responsive security system monitor. The system will
primarily interface with telephony protocols which include dual tone multi
frequency (DTMF), caller identification (CID), and some applicable telephony
circuit standards.
1.5 ORGANIZATION OF DOCUMENTATION
In this project documentation we have initially put the definition and
objective of the project as well as the design of the project which is followed by
the implementation and testing phases. Finally the project has been concluded
successfully and also the future enhancements of the project were given in this
Documentation.
LITERATURE SURVEY
2.1 INTRODUCTION
Design for an automated door locks(smart key less entry), Biometric
attendance, lecture theater/hall monitor system, railway station display, Automated
Parking System, gps navigation system, Circuit Encoder ARC M3EA from Artech
for RF Remote Control, pic16f877 interfaced to max sonar ez1 sensor, Infrared
Head phone, Microcontroller application, The first method of DTMF generation
provides two PWM (Pulse Width Modulation) outputs on pins G3 and G2 of the G
port for 100 ms. These two PWM outputs represent the selected high band and low
band frequencies respectively, and must be combined externally with an LM324 op
amp or equivalent feedback circuit to produce the DTMF signal DTMF (Dual Tone
Multiple Frequency) is associated with digital telephony, and provides two selected
output frequencies (one high band, one low band) for a duration of 100 ms. DTMF
generation consists of selecting and combining two audio tone frequencies
associated with the rows (low band frequency) and columns (high band frequency)
of a push-button touch tone telephone keypad.
According to the current article, DTMF was first introduced to the public at
the NY World's Fair in 1964. It was, however, in full "field test" usage in multiple
small towns in the US by then. Most notably, it was first used in Findlay Ohio in
1960 and then in Greensburg, PA in 1961.
WHAT IS DUAL TONE MULTI-FREQUENCY
DTMF is the global standard for audible tones that represent the digits on a
phone keypad with touch-tone land-line phones, pressing a key on the dial pad
generates the corresponding DTMF tone for that key. The land-line phone system
can then "listen" and decode that tone to determine which key was pressed,
enabling dialing.
4
Mobile phone networks use digital signals instead of DTMF for direct dialing,
but DTMF is still used over mobile phones to navigate automated systems such as
phone menus, and for secondary dialing, such as using a calling card. Each DTMF
"tone" is actually two tones - a low-frequency tone and a high-frequency tone -
combined. (Hence the name "dual tone multi-frequency".) Looking at the standard
phone keypad as a grid, the low tone corresponds to the row, while the high tone
corresponds to the column.
2.2 EXISTING SYSTEM
In the existing system of the project we had use the doors in lock systems
keys are obsolete they are use man power open and close the doors. It requires the
human energy.
2.3 DISADVANTAGES OF EXISTING SYSTEM
As mentioned above the earlier system has use the doors in lock systems
keys are obsolete there are no use of the electrical devices there are use the
mechanical systems. After being inspired by the mechanical door
opening system in that. I mean c'mon, door locks with keys are obsolete. Everyone
uses them. They’re so old fashioned! ...The second part of this project was to build
a DTMF decoder by use of mobile with the soft ware’s requirements.
2.4 PROPOSED SYSTEM
As the above disadvantages can’t be solved with in this application has
been Proposed and also the handling will be much improved than the existing
system as we are implementing the special method called door lock through
telephone using dtmf decoder.
Here the door lock through telephone using this is control the over all door
locking system there open are close the is process will take by D.C motors and
LED’S that can final operate.
5
CHAPTER 3
ANALYSIS
3.1 INTRODUCTION
After analyzing the requirements of the task to be performed, the next step
is to analyze the problem and understand its context. The first activity in the phase
is studying the existing system and other is to understand the requirements and
domain of the new system. Both the methods are equally important but the first
system states as a basis of giving the functional specifications and then successful
design of the proposed system. Understanding the properties and requirements of a
new system is more difficult and requires creative thinking as well as
understanding of existing system is also difficult. Improper understanding of
present system can lead diversion from solution
3.2 Hardware requirement
3.2.1 DC Motors
Industrial applications use dc motors because the speed-torque relationship
can be varied to almost any useful form -- for both dc motor and regeneration
applications in either direction of rotation. Continuous operation of dc motors is
commonly available over a speed range of 8:1. Infinite range (smooth control
down to zero speed) for short durations or reduced load is also common.
Dc motors are often applied where they momentarily deliver three or more
times their rated torque. In emergency situations, dc motors can supply over five
times rated torque without stalling (power supply permitting).
Dynamic braking (dc motor-generated energy is fed to a resistor grid) or
regenerative braking (dc motor-generated energy is fed back into the dc motor
supply) can be obtained with dc motors on applications requiring quick stops, thus
eliminating the need for, or reducing the size of, a mechanical brake.
Dc motors feature a speed, which can be controlled smoothly down to zero,
immediately followed by acceleration in the opposite direction -- without power
circuit switching. And dc motors respond quickly to changes in control signals due
to the dc motor's high ratio of torque to inertia.
DC Motor types: Wound-field dc motors are usually classified by shuntwound,
series-wound, and compound-wound. In addition to these, permanentmagnet
and brushless dc motors are also available, normally as fractionalhorsepower
dc motors. Dc motors may be further classified for intermittent or
continuous duty. Continuous-duty dc motors can run without an off period.
DC Motors - Speed control: There are two ways to adjust the speed of a
wound-field dc motor. Combinations of the two are sometimes used to adjust the
speed of a dc motor.
DC Motor - Shunt-field control: Reel drives require this kind of control. The
7
dc motor's material is wound on a reel at constant linear speed and constant strip
tension, regardless of diameter.
Control is obtained by weakening the shunt-field current of the dc motor to
increase speed and to reduce output torque for a given armature current. Since the
rating of a dc motor is determined by heating, the maximum permissible armature
current is approximately constant over the speed range. This means that at rated
current, the dc motor's output torque varies inversely with speed, and the dc motor
has constant-horsepower capability over its speed range.
DC Motors - Selection: Choosing a dc motor and associated equipment for
a given application requires consideration of several factors.
DC Motors - Speed range: If field control is to be used, and a large speed
range is required, the base speed must be proportionately lower and the motor size
must be larger. If speed range is much over 3:1, armature voltage control should be
considered for at least part of the range. Very wide dynamic speed range can be
obtained with armature voltage control. However, below about 60% of base speed,
the motor should be de-rated or used for only short periods.
DC Motors - Speed variation with torque: Applications requiring constant
speed at all torque demands should use a shunt-wound dc motor. If speed change
with load must be minimized, a dc motor regulator, such as one employing
feedback from a tachometer, must be used. When the dc motor speed must
decrease as the load increases, compound or series-wound dc motors may be used.
Or, a dc motor power supply with a drooping volt-ampere curve could be used with
a shunt-wound dc motor.
DC Motors - Reversing: This operation affects power supply and control,
and may affect the dc motor's brush adjustment, if the dc motor cannot be stopped
for switching before reverse operation. In this case, compound and stabilizing dc
motor windings should not be used, and a suitable armature-voltage control system
should supply power to the dc motor.
DC Motors - Duty cycle: Direct current motors are seldom used on drives
that run continuously at one speed and load. Motor size needed may be determined
by either the peak torque requirement or heating.
DC Motors - Peak torque: The peak torque that a dc motor delivers is
limited by that load at which damaging commutation begins. Dc motor brush and
commentator damage depends on sparking severity and duration. Therefore, the dc
motor's peak torque depends on the duration and frequency of occurrence of the
overload. Dc motor peak torque is often limited by the maximum current that the
power supply can deliver.
Dc motors can commutate greater loads at low speed without damage.
NEMA standards specify that machines powered by dc motors must deliver at least
150% rated current for 1 min at any speed within rated range, but most dc motors
do much better.
8
DC Motors - Heating: Dc motor temperature is a function of ventilation and
electrical/mechanical losses in the machine. Some dc motors feature losses, such as
core, shunt-field, and brush-friction losses, which are independent of load, but vary
with speed and excitation.
The best method to predict a given dc motor's operating temperature is to
use thermal capability curves available from the dc motor manufacturer. If curves
are not available, dc motor temperature can be estimated by the power-loss
method. This method requires a total losses versus load curve or an efficiency
curve.
For each portion of the duty cycle, power loss is obtained and multiplied by
the duration of that portion of the cycle. The summation of these products divided
by the total cycle time gives the dc motor's average power loss. The ratio of this
value to the power loss at the motor rating is multiplied by the dc motor's rated
temperature rise to give the approximate temperature rise of the dc motor when
operated on that duty cycle.
Selecting DC motors
Sizing a DC motor to accurately meet a set of requirements can be a
thankless task. Having to choose between brush-type or brushless motors can
complicate the selection. Even experienced designers may sometimes overlook
critical motor parameters and find problems after the system is up and running. In
the worst case, starting over may be the only alternative.
Experts, however, use an expedient procedure to properly size and select dc
motors. This procedure is based upon an accurate definition of the target system
parameters and designer experience.
Dc motor parameters: Fortunately, several motor parameters are the same
for both brush-type and brushless dc motors. One of these is motor constant; Km. It
is important but widely overlooked. It is used during motor sizing because it is a
figure of merit of the motor power-to-torque ratio. Km is proportional to the ratio of
peak torque, Tp, to peak power, Pp, at stall: Km = Tp / Pp. Km is also proportional
to the ratio of torque sensitivity, Kt, to motor terminal resistance, Rm:Km = Kt /
Rm.
After the required Km has been determined, a candidate motor with this
value or greater is selected from a catalog. The motor is only a candidate at this
point because other factors must be determined. As the design selection progresses,
some trade-offs typically take place. For example, the motor must also satisfy
physical size and inertia requirements.
Winding resistance is a major factor in motor selection because it seriously
affects Km. Winding resistance and motor current produce power loss in the form
of heat and motor temperature rise (TPR). These losses are also referred to as I2R
losses and directly degrade motor efficiency.
9
Most motor windings are copper wire which has a positive temperature
coefficient. A winding temperature rise from 25 to 155°C increases wire resistance
as much as 50%. Likewise, a proportional decrease in resistance occurs for
temperature drops.