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.
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.
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.
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
