This document describes the working of an automatic rain sensing windshield wiper system. It contains an infrared sensor that detects raindrops on the windshield by measuring the amount of reflected infrared light. When the sensor detects enough raindrops have accumulated, it sends a signal to automatically operate the wiper motor at a speed based on how quickly more moisture builds up. The system provides safety and convenience by allowing drivers to keep their hands on the wheel without manually adjusting wiper speed as road conditions change.

1. AUTOMATIC
RAIN SENSING
WINDSHIELD
WIPER
ANKITA SINGH
3RD YEAR

2. INTRODUCTION
The RainTracker automotive rain sensor,
senses rain or snow hitting the windshield,
and automatically runs the wipers at the
right speed.
we don't have to take our hands off the
wheel, or constantly adjust the speed of
the wipers as road conditions change.
cont…..

3.  A rain sensor or rain switch is a switching device
activated by rainfall
In this the sensor projects infrared light into the
windshield at a 45-degree angle
If the glass is dry, than most of this light is
reflected back into the sensor by the front of the
windshield.
If water droplets are on the glass, than it reflect
the light in different direction…the wetter the
glass, the less light makes it back into the sensor.
 cont….

4. The electronics and software in the sensor turn
on the wipers when the amount of light
reflected onto the sensor.
 software sets the speed of the wipers based
on how fast the moisture builds up between
wipes. It can operate the wipers at any speed.

5. Requirements
A BATTERY
AND
SENSOR
CONTROL
UNIT
WIPER
MOTOR

6. High Level System Diagram

7. DISCRIPTION
 In this battery supplies the power to
the sensor
 Then the wiper motor is automatically
on during the time of rainfall
 This sensor is fixed in the vehicle glass
Cont….

8. It senses the rainfall and giving control
signal to the control unit
The control unit activate the wiper
automatically
 The rain sensor works on the principle
of using water for completing its circuit
 So when rain falls on it it’s circuit gets
completed.

9. NE555 IC

10. Circuit diagram

11. WORKING
 The circuit presented here is not using
the optical technology
 It is built around the famous NE555 timer
IC that is working as a monostable
multivibrator here.
 The circuit is using a handmade sensor to
detect raindrops.
 The sensor can be made by attaching 2
wires of 0.5 inch.
Cont….

12.  When two wire in the hand made sensor
will detect raindrops then the output of
the NE555 IC at the output pin 3 will goes
high
 activates the relay for a set time period
and after that time period is over the
relay will switch off again.
 The activation time period of the relay is
few seconds but it can be increased by
increasing the value of the capacitor Cx.

13. Objective
Detect
intensity of
rainfall
Detect rainfall on
windshield
Improve safety by
decreasing driver
distraction
Automatically activate windshield
wipers once rainfall is detected

14. Applications
Rain sensing
wipers are great
convenience
feature in a luxury
car
more
useful in
marine
applicati
ons.
It is use in aircraft
fit in
existing
housing
area

15. ADVANTAGE
Sensor cost is low
High accuracy
AutomaticWindshieldWipers
Automatic Braking
Hands-Free Calling
Less power consumption
Automotive Safety and Convenience

16. Additional cost is
required in case
optical sensor is
used
This system is
applied in the case
of water falling on
the glass only
DISADVANTAGE

18. ANY QUESTION