This document describes a project to design an automatic vehicle braking system that applies the brakes when any obstacle is detected. The system uses RF to control the vehicle's movement. A distance sensor detects obstacles and sends a signal to a microcontroller, which stops the vehicle's motor if an obstacle is too close. This makes driving safer by preventing accidents from unexpected obstacles. It could be useful in military vehicles to prevent accidents caused by driver fatigue on long trips.

3. AIM OF THE PROJECT
Our aim is to design a breaking system that apply a
break in vehicle automatically on facing any obstacle.
This project is helpful in military vehicle where the
chances of sleeping of driver during driving may occur
because they have to travel upto very long distances and
in night time also this system provide the automatic
breaking if any obstacle suddenly arrive in vehicle way .
In this way it can protect any unusual accident.
This system made driving easier and safe .

4. WORKING OF THE PROJECT
R.F is used for operation vehicle. Automatic breaking are applied incase
obstacle detection.
Here we are using a toy car for presenting the working of the vehicle breaking
system .The movement Toy car is controlled through rf Transmitter ,frequency
signal is sent from the transmitter to the receiver connected to the car on
receiving signal it convert it into digital form and forward it to the 89c2051
controller ,wheel of the car is connected to the motor which in turn connected to
89c2051 controller so by executing instructions loaded with in the controller it
can control the dc motor and hence control the movement of the car .A distance
sensor is used here with the car, it can sense the distance of any obstacle and
generate an analog signal corresponding to the distance and forward to the PIC
controller ,a Pic controller has inbuilt ADC so it can convert an analog signal into
digital signal and forward it to the 89c2051 microcontroller for decision making
.In case if any obstacle found in vehicle way it stop the running of motor and
stop the car at that point .

5. CAPACITOR
A capacitor or condenser is a passive electronic
component consisting of a pair of conductors separated
by a dielectric (insulator). When a potential difference
(voltage) exists across the conductors, an electric field
is present in the dielectric. This field stores energy and
produces a mechanical force between the conductors.
The effect is greatest when there is a narrow
separation between large areas of conductor, hence
capacitor conductors are often called plates.

6. SENSING UNIT DESCRIPTION
In the SENSING section we are controlling the movement
of robot by transmitting radio frequency and control the
neck of robot with the help of microcontroller.
RF Transmitter :
This transmitter can be either high level or low level. The
RF oscillator invariably makes use of a crystal controlled
oscillator to ensure high accuracy of the carrier frequency
as recommended by the FCC. It is followed by a Class-A
RF buffer amplifier which provides a high impedance load
for the oscillator to minimize drift. Then the carrier signal is
subsequently amplified using a Class-C RF amplifier. For
high level modulation, the final stage is another class-C RF
output amplifier at which the modulating signal is amplified.

8.
VARIABLE RESISTOR
In electronic circuits, sometimes it becomes necessary to adjust the
values of currents and voltages. For n example it is often desired to
change the volume of sound, the brightness of a television picture
etc. Such adjustments can be done by using variable resistors.
Although the variable resistors are usually called rheostats
in other applications, the smaller variable resistors
commonly used in electronic circuits are called
potentiometers.

9. DIODE
ACTIVE COMPONENT-
Active component are those component for not any other component are used its
operation. I used in this project only function diode, these component description
are described as bellow.
SEMICONDUCTOR DIODE-
A PN junctions is known as a semiconductor or crystal diode.A crystal diode has
two terminal when it is connected in a circuit one thing is decide is weather a
diode is forward or reversed biased. There is a easy rule to ascertain it. If the
external CKT is trying to push the conventional current in the direction of error,
the diode is forward biased. One the other hand if the conventional current is
trying is trying to flow opposite the error head, the diode is reversed biased putting
in simple words.

10. CONNECTORS
Connectors are basically used for interface between two.
Here we use connectors for having interface between PCB and
8051 Microprocessor Kit. There are two types of connectors
they are male and female. The one, which is with pins inside, is
female and other is male.
These connectors are having bus wires with them for
connection.
For high frequency operation the average circumference of a
coaxial cable must be limited to about one wavelength, in order
to reduce multimodal propagation and eliminate erratic
reflection coefficients, power losses, and signal distortion. The
standardization of coaxial connectors during World War II was
mandatory for microwave operation to maintain a low reflection
coefficient or a low voltage standing wave ratio.

11. 
• The project of automatic vehicle breaking has
successfully completed and working properly .The
system can be employed in the original car by
providing the connection of the microcontroller
with the break system ,So that break will press as
soonas any obstacle will detected. This system is
very useful in today’s traffic on road and prevent
from the daily accidents .