Automated car parking system

Design

A display is provided at the ground floor which is a counter that displays number of cars in each floor. It informs whether the floor is ful or not. Cars can be lifted up and down! Lift is controlled by stepper motor. An indicator with a green and red LED is kept in all the floors to indicate whether the lift is busy or is it ready to take the car up or down. If the red LED glows that means the lift is already engaged and the person has to wait for the green LED to glow. In this project we have provided three floors of a building for car parking. Maximum storage capacity of each floor is given as ten. Storage capacity can be changed according to the requirement.

When the car enters the lift, the LDR detects its presence and sends a signal to glow RED LED indicating that the lift is busy. It also sends a signal to motor which makes the motor to rotate. After RED LED glows the lift will take the person and the car up to the floor where the space for parking is available. (For VIP it will be the third floor). When the lift reaches the first floor, the processor compares the filled amount to that of the already fed capacity of that floor, and if it finds that the first floor is fully filled , it goes to the second floor and thus the procedure stops here. As soon as a car is placed in a particular floor, the display counter at the ground floor increments as to indicate the floor capacity has decreased by one. After the lift places the car in a particular floor, it comes back to its normal position and that time, the motor that drives it , also stops. Now processor sends signal to glow GREEN LED indicating that lift is free.

When a person needs to come down from a particular floor to ground floor, he is expected to focus the headlight onto the LDR placed in that floor. Now sensor section sends signal to motor that the lift has to be send back to that particular floor and sends a signal to glow RED LED indicating that the lift is busy. As soon as the lift reaches that particular floor car should come inside the lift, the display counter at the ground floor decrements by one as to indicate the floor capacity has increased by one. Lift comes back to its normal position and that time, the motor that drives it, also stops. Now processor sends signal to glow GREEN LED indicating that lift is free.

If there no parking taking place, the processor carries out the job according to the following priority:-

1. It checks whether any password is entered.
2. It checks whether any car is entered to lift.
3. It checks whether any car headlight is pressed in front of LDR placed in each floor.

It is like a round robin system.

3. Hardware description:

Introduction to 8051 Microcontroller:

The 8051 microcontroller generic part number actually includes a whole family of microcontrollers that have numbers ranging from 8031 to 8751.The block diagram of the 8051 shows all of the features unique to microcontrollers:

1. Internal ROM and RAM
2. I/O ports with programmable pins
3. Timers and counters
4. Serial data communication

The block diagram also shows the usual CPU components program counter, ALU, working registers, and the clock circuits.

The 8051 architecture consists of these specific features:

1. 8 bit CPU with registers A and B
2. 16 bit PC &data pointer (DPTR)
3. 8 bit program status word (PSW)
4. 8 bit stack pointer(SP)
5. Internal ROM or EPROM (8751)of 0(8031)to 4k(8051)
6. Internal RAM of 128 bytes.
7. 4 register banks , each containing 8 registers
8. 80 bits of general purpose data memory
9. 32 input/output pins arranged as four 8 bit ports:P0-P3
10. Two 16 bit timer/counters:T0-T1
11. Two external and three internal interrupt sources
12. Oscillator and clock circuits

A pin out of the 8051 packaged in a 40 pin DIP is shown below.