Automatic Rain Sensing Wiper Circuit using 555 Timer IC

You have seen Automatic Wiper System in luxury cars where Windshield Wiper automatically gets activated when there is Rain or if there is some water on the windshield. Electronic Wiper is very common device that is attached in every car to wipe the water on the windshield during the rain. But generally they are manually operated and we need to switch them ON manually. But today we are going to build Automatic Rain Sensing Car Wiper System using 555 Timer IC. This circuit automatically detects the rainfall and activates the wiper to clear the windscreen.

 

 Components Required:

  • 555 Timer IC
  • L293D
  • IC LM358
  • Transistor BC557
  • Resistors (1K, 10K, 2.2M)
  • Capacitors (0.01uf, 0.47uf)
  • DC Motor
  • Rain Sensor
  • Power supply (5-12v)

 

Circuit Diagram and Explanation:

Automatic Rain Sensing Wiper using 555 Circuit Diagram

This Automatic Rain Sensing Wiper Control Circuit can be divided into four parts. First part includes 555 IC in Astable Mode, second part includes Comparator LM358, third part has Motor Driver circuitry using L293D and forth part is Rain Detector.

For Astable Multivibraror, we have used a 555 Timer IC for generating pulse in every 2-3 seconds (depends on capacitor value), means 555 Timer IC is configured in Astable mode. Output of Astable Multivibrator is directly connected to inverting pin of Comparator LM358 and Pin No 7 of Motor Driver L293D. Output of comparator is directly connected at pin 2 of motor driver IC. Comparator LM358 IC is used here for comparing 555 timer IC’s output voltage and reference voltage across comparator’s non inverting terminal, set by using Voltage Divider Circuit (R3 and R4). Two LEDs have been used, one at the output of 555 Astable circuit and other at the output of comparator LM358. A Water Detector or Rain Sensor is used for detecting the water or rain. Output of Astable Multivibrator and Comparator is applied to motor driver IC L293D, which will further drive the wiper motor. Whole circuit can be powered using 5v-12v battery depending upon the application.

 

Working Explanation:  

Working of this Automatic Rain Sensing Car Wiper project is simple. As we already explained that this circuit has four parts namely Astable Multivibrator, Comparator, Motor Driver and Rain Detector. When water drops of rain falls over the Rain Sensor then it will trigger the PNP transistor BC557 and PNP transistor turns ON the power supply of whole circuit and circuit start working until there is water on the Rain Sensor. Now after the power supply has been turned ON, Astable Multivibrator starts oscillating in configured frequency.

Automatic-Rain-Sensing-Car-Wiper-using-555-block-diagram

Now when the output of 555 Timer IC goes HIGH then the comparator LM358 gives LOW output and when the output of 555 IC goes LOW then the Comparator’s output goes HIGH. And by using these two outputs DC motor turns clock wise and anticlockwise and wiper attached to it turns right to left and left to right, through Motor Driver IC L293D. That is how the wipers automatically sense rain and gets activated. They remain activated until there is water on Rain sensor, as soon as the water evaporates wipers get stopped. Two LEDs are also used here used for indication. You can see the whole working of this project in the Video below.

 

Building the Rain Sensor:

Rain Sensor is also called Rain Detector or Water Detector. Although they are easily available on any Electronic Shop or on any Online Electronic Store but you can also build them easily at your home. Here we are briefly explaining the steps:

Step 1: Take Copper Clad Board of approx. 2 inch of length and same width and rub it by using the sand paper.

building-rain-sensor-on-pcb-1 building-rain-sensor-on-pcb-step1-2

 

Step 2: Now take the Black tape or Cello tape and stick it to the Clad board as shown in the diagram.

building-rain-sensor-on-pcb-step2-1 building-rain-sensor-on-pcb-step2-2

 

Step 3: We only need copper tracks under the black tape. So we need to remove all the other copper except under the black tape.  For this, make Ferric chloride solution (FECL3), by adding 2-3 tea spoon of Ferric chloride in some water. This solution is called Itching Solution. Put the PCB in this solution for approx. half an hour.

building-rain-sensor-on-pcb-step3

 

Step 4: Ferric chloride will react and remove the exposed copper and won’t react with the masked copper under the Black tape. Now take out the PCB from the solution without touching the solution and remove the Black tapes.

building-rain-sensor-on-pcb-step4-1 building-rain-sensor-on-pcb-step4-2

 

Step 5: Finally solder two wires on the two created coppers ‘tracks’ as shown in the figure and you have your Rain Sensor ready to use.

building-rain-sensor-on-pcb-step5-1 building-rain-sensor-on-pcb-step5-2

We also recommend you to go through this article: How to make a PCB at home, before building the Rain Sensor yourself.

Video: 

Comments (31)

  • Devendra Mishra's picture
    Devendra Mishra

    HELLO I USED RAIN SENSING CIRCUIT WHICH IS PROVIDED BY YOU I TRIED IT ON BREADBOARD AND IT GLOWS ONLY TWO LED'S WHEN I PRESS BOTTON(USED INSTEAD OF RAIN SENSOR) IT GETS TURNED OFF. I HAVE SEEN YOUR VIDEO AND U USED TWO ELECTROLYTIC CAPACITOR I GOT CONFUSED WITH IT. PLEASE PROVIDE ME A NEW BUIL CIRCUIT WITH A COMPONENT DETAILS IT WILL BE A BIG HELP FOR ME HOPING U WILL REPLYAS SOON AS POSSIBLE.

    Sep 03, 2016
  • Abhishek's picture
    Abhishek

    They are two 1uF capacitors connected in series to make it 0.5uF (~0.47uf). Capacitor connected in series are calculated as 1/C= 1/C1 + 1/C2. If you have 0.47uf capacitor, you can use it directly.

    Oct 01, 2016
  • Melencion's picture
    Melencion

    Also please remember that the R1 should be 1kohm and R2 should be 2.2Mohms ...

    Oct 09, 2016
  • Chiranjeet Chowdhury's picture
    Chiranjeet Chowdhury

    Sir i have followed every instruction given and the circuit is working, but i am getting a problem that the wiper keeps shifting after each oscillation towards the right. Time constant seems to be correct and each cycle is perfectly equal just that the wiper is shifting after each cycle towards right. Please help sir my project is almost over just facing this problem. Waiting for your quick reply. Thank you.

    Oct 11, 2016
  • Piyush's picture
    Piyush

    What happend when we not use electrolytic capacitor

    Oct 16, 2016
  • adarsh's picture
    adarsh

    can u tell me which type of motor is used in the video?

    Nov 09, 2016
  • corbin catlett's picture
    corbin catlett

    I am building this for a class in school and am having some issues. First when the power supply is turned on the motor runs constantly. I believe something is not right with the astable multivibrator as the first led does not blink it only glows brightly. The second Led blinks dimly. Any help is greatly appreciated thanks!

    Nov 12, 2016
  • Fuseini Kamaldeen's picture
    Fuseini Kamaldeen

    pls I've choose Automatic rain sensing wiper circuit using 555 timer IC,So hw do are write the proposal?

    Nov 15, 2016
  • ricardo's picture
    ricardo

    Sir i have followed every instruction given and the circuit is working, but i am getting a problem that the wiper rotates 360 degrees. please help me sir. thankyou

    Nov 17, 2016
  • Abhishek's picture
    Abhishek

    Try changing the frequency output of 555 timer by changing the value of R1 and C1.

    Dec 02, 2016
  • Terrance Johnson's picture
    Terrance Johnson

    Do you have a spreadsheet of the complete parts list with manufacturer, part number and description, ect.?

    Nov 29, 2016
  • reema's picture
    reema

    hi sir , actually i had a problem while connecting and lost my PNP transistor , and don't have much time to get a new one can i replace it with NPN and how is that. I'll appreciate your help thnx ^^

    Dec 06, 2016
  • Saiful's picture
    Saiful

    Can i see the flowchart for this experiment..? I still don't really understand.

    Dec 20, 2016
  • ataasu Christopher's picture
    ataasu Christopher

    after Constructing the cct the motor rotate both 360 with speed. what could be the possible problem

    Jan 22, 2017
  • Maddy's picture
    Maddy

    Properly configure the 555 IC in astable multivariator mode.

    Jan 28, 2017
  • Huehue's picture
    Huehue

    Hi, can i replace the transistor with an SCR thyristor? Will it work?

    Jan 31, 2017
  • Boateng Alfred's picture
    Boateng Alfred

    I have constructed the circuit and it is working but only the DC motor does rotate in clockwise and not anti_clockwise. Is there a way out for me ?

    Feb 01, 2017
  • Janson's picture
    Janson

    Hey, I've done the circuit and the .motor is rotating in one direction.
    So I checked if the astable multivibrator is producing oscillations it seems that the led just glows continuously and is not blinking also led for the comparator is glowing very dim.
    What should i do

    Feb 25, 2017
  • Janson's picture
    Janson

    I've used the components as specified in the site but the astable multivibrator is not producing oscillations

    Mar 04, 2017
  • Janson's picture
    Janson

    It worked.Motor is working in both directions but it's rotating at the same time.what should i do ?
    I've made t1=0.53 and t2=0.429 seconds and r1-150ohm ,R2=620 ohm and c1 =1000micro farad

    Mar 04, 2017
  • A Sudharshan's picture
    A Sudharshan

    sir i have connected all the devices as per circuit diagram given but water drops are not detected , i could not find which device is in problem so kindly give u r suggestion on telling which device may have fault

    Mar 09, 2017
  • Lovjinder Singh's picture
    Lovjinder Singh

    Sir what type of rain sensor is used

    Mar 25, 2017
  • Tanmay chatterji.'s picture
    Tanmay chatterji.

    Sir I have used a sg90 servo motor. Would it work?
    If dc motor ,what type of dc motor should I buy

    Mar 29, 2017
  • jainish's picture
    jainish

    please don't use water sensor that u purchase fro the shop as it can work only on Audino

    Apr 13, 2017
  • Satwaik Sihi's picture
    Satwaik Sihi

    how to connect the power supply i have a 5v and 12v adapter ho to connect to the breDBOARD

    May 14, 2017
  • Dharmil Shah's picture
    Dharmil Shah

    Sir, do we need to supply Vcc to all the IC's individually or just to the emitter of PNP transistor?

    Aug 22, 2017
  • Viraj Savaliya's picture
    Viraj Savaliya

    Both thw leds are glowing together and motor is also rotating in one direction Irrespective of water droplets been present on the senor, I have connected the circuit as specified by the diagram. What are the possible errors/changes needed in the circuit?

    Aug 24, 2017
  • srikar's picture
    srikar

    unlike your experiment i tried 555 in monostable and l293d also.I want a suggestion can i forcefully stop the wiper for certain angle?will motor get damage?plz help

    Sep 21, 2017

Leave a comment