AUTOMATIC SPEED CONTROLLED CAR

AUTOMATION FOR SAFETY

Submitted to

Md. Hasibul AlamLecturer, Department of EEE, BUET

Submitted by

0906166, 0906167, 0906168, 0906169,0906170, 0906171, 0906172, 0806027

OBJECTIVE:• To design a car which will detect speed breakers and large

obstacles and control its speed accordingly to avoid damages.

COMPONENTS:• 2 Ultrasonic Sensors (HC- SR04)• 1 ATMEGA32A• 1 L293D Motor Driver• Switches• Resistors

COMPONENTS:

HC- SR04

• 2 sensors are used• Includes ultrasonic transmitter, receiver and control circuit• Upper one for large obstacles• Lower one for speed breakers

COMPONENTS:

HC- SR04

Wiring connections• 5V VCC• Trigger Pulse Input• Echo Pulse Output• Ground

COMPONENTS:

HC- SR04

The basic principle of work of HC - SR04 :• Using IO trigger for at least 10us high level signal,• The Module automatically sends eight 40 kHz and detect whether there is a pulse signal back.• IF the signal back, through high level , time of high output IO duration is the time from sending ultrasonic to returning. Test distance (in meters)= (high level time × velocity of sound (340M/S) /2•Distance in inches = Time / 148

OPERATION:

Speed Breakers:• If a car running at V m/s detects a speed breaker 2 feets away,

it reduces its speed to V/2 m/s• When the distance is 1 feet, its speed reduces to V/4 m/s

OPERATION:

Speed Breakers:• After crossing, the speed again increases to V m/s

OPERATION:

Large Obstacles:• If a large obstacle is detected, the car stops at 6 inches distance

CIRCUIT DIAGRAM:

Upper Sensor

Lower Sensor

LIMITAIONS AND SAFETY:• L293D is heat sensitive, so operation can be hampered in case

of large power drop• Heat sink should be used in whole system

ADVANTAGES:• Security from damages• Attractive for Electric Propulsion Motors• Effective in highly populated areas• Applicable for carrying goods in hospitals, industries, spaceships

etc.• Important feature for vehicles used for collecting informations

in areas men cannot reach

FUTURE APPLICATIONS:• Addition of wi-fi device to communicate with other cars around

to avoid collisions• Addition of direction change systems

THANK YOU