New Year is near! Is a festival of happiness. My family and I planned to go to the province for several days. Leaving the house for days may be stolen our property. I decided to buy or build the Ultrasonic sensor circuit project with versatile controls. Principle similar to radar systems is when we send out the waves, then detects the reflected wave back. If have foreign object, causing the wave to get back, there is a chang and The control system is running, this circuit can be detected, both indoors and outdoors.
For example that we take this system to use widely is a car parking system sensor or a burglar alarm with motion sensors.
How This Circuit works
From circuits in Figure 1 is the motion sensor circuit. The working of circuit to start from when we apply a power supply 12 volt to input point 12 volt. Then the electrical flow through a diode D11, that is protector the wrong electrodes of users.
When current flowed through diode D11 will be filtered to smooth by C16 then is divided into two way are first to the relay RY1 and other way into an input of IC4 to reduce voltage from 12 volt only remain 9 volt, This level voltage will be supplied to many the circuit s.
On begin the circuit is delayed with these components are IC3/4, R23, C13 and D10. Which the IC3/4 will apply voltage to pin 13 of IC2/2, that has voltage more than pin 12. So as a result to pin 14 of IC2/2 has logic into “0”. The does not works,although it is moving. But when at pin 10 of IC3/4 changed a logic state from “1” into “0”, since C13 begin charged fully the voltage. IC2/2 will release a working to normal. This section circuit will delay the time about 10 second to who switch ON this project had a chance to leave the area. Before it will be ready to detect motion.
Secondly an ultrasonic wave transmitter consists of IC3/1, IC3/2, IC3/3, C15, R27, R28 and VR4. They IC3/2 and IC3/3 are oscillator generator circuit with frequency about 40 Khz, then they is amplified by IC3/1 before send to before being sent to the ultra-sonic transmitter on.
On the part of receiver section when When the ultra sonic sensor get an ultrasonic waves from the transmitter. Then they is amplified by the IC1 that the gain ratio is determined by R1 and C1. The other signal that is boosted up that combination of Q1,R4 and R5 will amplified the signal up to. And the other signal can pass through C5 to filter a current by both D2 and D3 became to Direct Current(DC).
In normal state when no the movement, the ultrasonic wave will be a steady pulse. But when it is moving, it will makes ultra sonic waves to get into. Have been rectified by D2 and D3 will have a ripple. When it is motion C14 to reduce the output ripple From the rectifier D2 and D3. This signal will come to C6 and R7 got to pin 9 of IC2/1, IC2/1, they amplify a incoming signal is ripples, with VR1 determines the gain of IC2 / 1 and is sensitive to the location where we install.
The amplified ripple signals will be send to through C8, by has D4 and D5 are rectifier as DC volt, then they is compered by the IC2/2, after that when DCV on pin 12 has value more than pin 13 of IC2/2 will makes voltage out to pin 14 via the D6 into pin 3 of IC2/3 , while the charging voltage to C11. The IC2/3 is also a voltage comparator like IC2/2 But the extra pin 3 of IC2 / 3 R17 and C11 will be a delay.
On pin 4 of IC2 / 2 sends out voltage makes Pin 1 of IC2 / 3 will send also Voltage. Makes pin B of Q2 to get bias so it conductors and the relay RY1 also works, while the LED1 lit up as well.
But when not moving on pin 12 will has lower voltage than pin 13 of IC2/2 , then on pin 14 no volts. But at pin 3 of IC2/3 remain has voltage, because the C11 has voltage remain but in same time it is discharged by the R17 , makes voltage on pin 3 of IC2/3 has reduce value steadily until lower than voltage at pin 2 of IC2/3. Which voltage at pin 2 we can set by adjusting VR2, the Q2 will stop working together with Q3 will start to protect a repeat, by will send a positive pulse out to pin 13 of IC2/2.
IC2/4 will connected in the comparator circuit style. To helper in adjusting freqency of receiver section. If we fine VR4 until has frequency of 40 Khz, The LED2 will glow up since two amplifier section will amplify frequency of 40 KHz makes on D3 has a high voltage, but If the frequency is not correct, it will have lower the voltage.
Let’s to assemble (How to builds)
To begin with preparation PCB as shown in Figure 2, and soldering equipment neatly. The IC2 and IC3 should insert in the socket, the IC1 should solder with carefuly because canot insert to secket IC. The receiver and Transmitter must be installed correctly.
Testing and customization
Check the circuit for error, then Let’s to adjust, by before apply the voltage supply to our project, we must connected to the shielded cable is about 15 cm between the ultra-sonic transmitter with the the join connected poin to TX.
Next fine VR4 to extreme left. Then apply voltage into this circuit and measure voltage at pin 6 of IC2/4 , after that adjust VR3 until can read 4.9 volt on the voltemeter.
Then turned to the ultra-sonic transmitter to straight on to the ultra-sonic receiver. With spaced about 1 cm, and then adjust VR4 slowly clockwise until LED2 brightness indicates that the frequency is 40KHz or nearby. Disconnect the power source. Then connect to the Ultra Sonic transmitter at the original, and then adjust VR1 and VR2 to the left hand the end.
Next, turned the Ultra sonic out to the open air, not moving, then power supply to the circuit, wait about 10 seconds, to cycle ready working before. Then Try a hand over the front of the Ultra sonic sensor, LED will light up. And then use the hand away from the front of the ultra-sonic, LED1 and relay RY1 continue to run for about 10 seconds.
Lastly they stopped working, first try adjusting VR2 to the right end, and use the ultrasonic through LED1 and will make relay RY1 work. And then took out the relay RY1 LED1 will continue to work for approximately 1 minute. Then it stopped, showing that the delay of the the circuit in the relay RY1 work correctly, the sensitivity can be adjusted with VR1.
For implementation. Usually, we can use a set of anti-theft, by the sound of a siren. At the output of the relay RY1, By relay RY1 serves as the power switch off, when the motion detector, siren will sound.
If made into an open light unattended at home as well. If the detector within a given room has a comfortable 4×6 Metz, but if more space. May need to install more than one machine.
Total parts list
R1__________________________1 ohm_____1 pcs.
R6,R8,R9,R12,R14,R21,R22,R25_10K______ 8 pcs.
R11_________________________100K_____ 1 pcs.
R13,R26_____________________ 8.2K_____ 2 pcs.
R20_________________________30K_____ 1 pcs.
R23,R28____________________150K_____ 2 pcs.
VR1________ 500K_______1 pcs.
VR3-VR4____10K________ 2 pcs.
C1,C7,C9,C10____1uF 16V____ Electrolytic Capacitors___ 4 pcs.
C2_____________0.01uF 50V___Polyester Capacitor_____ 1 pcs.
C3,C13,C16-17___100uF 16V___ Electrolytic Capacitors___ 4 pcs.
C4,C15__________0.0012uF 50V___Polyester Capacitor___ 2 pcs.
C5__________0.047uF 50V________Polyester Capacitor___ 1 pcs.
C6______________4.7uF 16V___ Electrolytic Capacitors___ 1 pcs.
C8,C14__________2.2uF 16V___ Electrolytic Capacitors___ 2 pcs.
C11______________47uF 16V___ Electrolytic Capacitors___ 1 pcs.
C12__________0.68uF 50V________Polyester Capacitor___ 1 pcs.
D1-D10______1N4148____ 75V 150mA Diodes_______10 pcs.
D11_________1N4001_____ 50V 1A Diodes___________1 pcs.
LED1-2______LED 3 mm__________________________2 pcs.
ZD1_________Zener diode 4.7V 0.5W________________1 pcs.
Q1__________BC547___ 45V 100mA NPN Transistor___1 pcs.
Q2__________2SC458___ 30V 200mA NPN Transistor__1 pcs.
Q3__________C9012____ 45V 800mA PNP Transistor___1 pcs.
IC2_________LM324__Quad/ 1MHz/ Operational Amplifiers for Commercial/ Industrial/ and Military Applications ___________________________ 1 pcs.
IC3_________CD4093_Quad 2 input Schmitt NAND Gate IC________________________1 pcs.
IC4______________LM7809__9 DC voltage regulator _______1 pcs.
Other circuits are recommended.
- PIR. motion sensor alarm circuit
- The PIR Movement detector with light-activated
- Smoke detector circuit
- Insect repellent device using ic 4047
GET UPDATE VIA EMAIL
I always try to make Electronics Learning Easy.