1.
INTRODUCTION
Human or animal can produce
sound. This sound is created by the physical movement whether the movement is
fast or slow depends on the medium that create the sound. Eventually these movements
can be detected by using an ultrasonic motion detector. Ultrasonic sound waves
are sound waves that are above range of human hearing and thus have frequency
above about 20000 Hz.
An ultrasonic motion detector
typically comprises at least one ultrasonic transducer which transforms
electrical energy into sound and, in reverse .Ultrasonic motion detector have
typically been used in application such as detecting and identifying solid objects,
measuring the shape and orientation of a work piece, detecting possible
collisions between objects to avoid collisions, room surveillance, flow measurement,
and determining a type of material by measuring the absorption of sound
A motion detector is a
electronic device that detects physical movement in a given area and transforms
motion into an electrical signal. The motion detector may be electrically
connected to devices such as security, lighting, audio alarms. Motion sensors
are used in a wide variety of applications. Motion detectors are mainly used in
for security systems.
Basically this project is to
design an ultrasonic motion
detector that detect physical movement of human ,animal or
anything that move the design is to
improve the use of sensor in detecting motion
.
2. BLOCK DIAGRAM OF ULTRASONIC MOTION
DETECTOR
|
40 kHz oscillator
|
|
Driver circuit
|
|
Vcc
|
|
Transmitting Transducer
|
|
Receiving transducer
|
|
Pre amplifier
|
|
Detector circuit
|
|
Output driver circuit
|
|
Vcc
|
3. BLOCK
DIAGRAM DESCRIPTION
3.1 POWER
SUPPLY SECTION: VOLTAGE REGULATOR (7805)
The 7805 is a voltage regulator. It
looks like a transistor but it is actually an integrated circuit with three legs.
It can take higher dc voltage and turn it into a nice, smooth 5v dc you need to
feed at least 8v and not more than 30v to do this. It can handle around 0.5 to
0.75 amperes, but it gets hot. So use a heat sink. Use it to power circuits
that need to use or runoff 5volts
3.2 TRANSMITTER SECTION
:( 4049 HEX INVERTER)
The 4049 provides six
inverting buffers with high current output capability suitable for driving TTL
or high capacitive loads. Since input voltages in excess of the buffers’ supply
voltages are permitted, the buffers may also be used to convert logic levels of
up to 15v to standard TTL levels
It operate over a recommended VDD power supply range of 3V to 15V referenced to VSS (usually ground)unused inputs must be connected to VDD,VSS, or another inputs. It is also suitable for use over the industrial (-40 0c to +85 0c) temperature range
It operate over a recommended VDD power supply range of 3V to 15V referenced to VSS (usually ground)unused inputs must be connected to VDD,VSS, or another inputs. It is also suitable for use over the industrial (-40 0c to +85 0c) temperature range
Features:
·
Accepts input voltages in excess of the supply voltage
·
Fully static operation
·
5v ,10v,and 15v parametric ratings
·
Standardized symmetrical output characteristics
·
Operates across the full industrial temperature range -40 0c
to +85 0c
Functional diagram (logic symbol)
Pin Configuration
of 4049 hex inverter:
3.3 RECEIVER
SECTION :( LM 324 QUAD OP-AMP)
The
LM 324 consist of four independent, high gain internally frequency compensated
operational amplifiers which are designed specially to operate from a single power
supply over a wide voltage range. Operation from split power supplies is also
possible so long as the difference between the two supplies is 3volts to 32
volts .Application areas include transducer amplifier, DC gain blocks and all
the conventional op-amp circuits which now can be easily implemented in single
power supply systems
Features:
·
Internally frequency compensated for unity gain
·
Large DC voltage gain :100 dB
·
Wide power supply range:3V to 32V
·
Input common mode voltage range include ground
·
Large output voltage swing :0V to VCC-1.5V
·
Power drain suitable for battery operation
Internal block diagram:
Schematic diagram of LM 324 quad
op-amp:
4.
COMPONENTS LIST
|
COMPONENTS
|
SPECIFICATION
|
QUANTITY
|
|
SEMICONDUCTORS
|
IN4148
IN4002
LM324
IC 4049
LED
BC 639
|
2
1
1
1
1
1
|
|
RESISTORS
|
100K
10M
2.2K
220K
1K
1M
1.2M
10K
47Ω
150K
1M POT
|
3
4
1
1
2
3
2
3
1
1
1
|
|
CAPACITORS
|
0.1µF
0.01 µF
0.47 µF
100pF
100 µF
33pF
|
2
3
3
1
1
2
|
|
ADDITIONAL PARTS & MATERIALS
|
40KHz CRYSTAL
40KHz ULTRASONIC RECEIVER
40KHz ULTRASONIC TRANSMITTER
9V BATTERY
|
1
1
1
1
|
5. CIRCUIT DIAGRAM OF ULTRASONIC MOTION DETECTOR
6. CIRCUIT DESCRIPTION
A 9V battery directly
provides power for some sections of the circuit .The battery is also connected
to a regulator, which provides a 5V DC power for other sections of the circuit.
The transmitter section of
the detector is basically a crystal controlled relaxation oscillator build
around a hex inverter .One of the hex inverter section along with resistors R21
and R22and capacitors C11 and C12pings the 40kHz crystal into sustained
oscillation. The remaining section act as a linear buffer to drive a 40 kHz
ultrasonic transmitting transducer.
The receiver section of
the circuit is made up of four AC coupled stages, each built around a one of
four sections of an op-amp. In the first stage, the input developed across R1
andR2is modulated by a 40 kHz, ultrasonic receiving transducer, and is then fed
to first op-amp where it is amplified. The receiving transducer detects any
reflected sound produced by the transmitting transducer .If there is movement the
resulting envelope signal is just a straight line: diode D1and resistor R8
operate as a negative peak detector to recover the envelope signal.
In the second stage the
recovered signal is again amplified .the time constant of the second op-amp
stage is quite slow so that the envelope can be followed; the output of the
second stage is DC level that represents the strength of the envelope .If there
is movement, the envelope will reflect it in the form o0f a positive or
negative signal.’
The third stage is a differential amplifier
build around the third op-amp. There two diodes D2 and D3 .They detect both
positive and negative pulses .When there is no movement the voltage at the
output of second stage is half the supply voltage and neither D2 nor D3 can
conduct
The fourth stage is around
the fourth op-amp is set up as a monostable flip-flop That stage converts any
signal that gets through the filter into a pulse substantial enough to turn on
transistor .when transistor conducts LED turns on .The time constant of the
monostable is about a half a second and is set up by C8 and R18 .The diode D4
is used to separate the charging and discharging time constants .It lets the
circuit to switch on immediately when movement is detected ,but allows half
second delay for the reset.
7. PCB DESIGN
PCB DESIGN PROCEDURE.
PCB
preparation can be done using the following steps.
·
Prepare the PCB layout of the circuit in
a graph sheet.
·
Cut the copper clad sheet in proper
dimension and wash it.
·
PCB layout is coated with paint or
sticker.
·
Prepare the ferric chloride solution
·
Dip the PCB in to fanic chloride
solution for etching non printed surface.
·
Wash cleanly with detergent.
·
Drill the holes in necis any position.
8.
PCB LAYOUT
9. SOLDERING
Soldering
is the process of joining two or more similar or dissimilar maters by melting
another meters having lower melting points.
9.1
SOLDERING FLUXES
In
order to make the surface accept the solder readily, the component terminals
should be for from order and other abstractly films. Soldering ttun cleans the
orders from the surface of the metal. Zinc chloride, aluminums chloride, and
rosin at the commonly used fluned.
9.2
SOLDER
Solder
is used for joining two or more mental at temperature below their melting
point. The popularly used solders on alloy of tin (60%) and lead (40%) that
metals at stiff and solidifies when it cools.
9.3
SOLDERING IRON
It
is used the melt the solder and apply at the joints in the circuit.
10.
ADVANTAGE
1. It is designed to be of low cost
2. It is built to be portable
11.
DISADVANTAGE
1.
Detection is restricted to limited areas
2.
Continuouns signaling of the device is not
possible, if a prowler quickly crosses the field of view.
3.
if an alarm circuit is used it has to be
run off a separate power supply from that used by the detector
12. APPLICATION
1.
For detecting and identifying solid objects.
2.
For measuring the shape and orientation of a work piece.
3.
For detecting possible collisions between object to avoid the collision
4.
For room surveillance
5.
For flow measurements
6.
For determining the type of material by measuring the absorption of sound
7.
Main application in security system
13.
CONCLUSION
Our project ultrasonic
motion detector finds many applications in our day to day life the .using the
basic theory behind the working of this
circuit it can be applied for implementing improved version of ultrasonic
motion detector circuits. So here by we once again thank everyone who
contributed directly or indirectly in the success of our projects summary
14.
FUTURE SCOPE
1.
Further modifications in the circuit can increase the area of detection .
2.
It can be implemented in the multilevel car parking system.
3.
Additional circuitry can be used with, to provide greeting notes to the guests,
or it can be even made to call the police in case of theft
APPENDIX
well described.
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