Automatic car parking indicator using 8051

This system will indicate empty and filled car parking slots at the entry. Now a days Car parking at shopping malls and markets is becoming a big issue and is causing to traffic jam. To avoid this  problem we are designing this system to indicate empty slots and filled slots, so that a car driving person can directly take his car to that particular empty slot. we will indicate the slot state by LEDs and also in LCD screen. we will use IR sensors to sense the presence of car in the slot.

Working: when a car enter into a empty slot the photo detector output will become '1', this will change the state of the slot to filled, otherwise it is remained in empty state only. like wise all the slots are detected by IR sensors.

Here is the functional flow chart

  to download C-code
  to see output video 
  to see working video -1

Schematic Diagram:

case'1': when all the slots are empty

all the LEDs are glowing and slot states are displayed in LCD  

here LED ON means slot empty; and LED OFF means slot filled 

case'2': when 1st and 2nd slots are filled

1st and 2nd LEDs are glowing and the same thing is displayed in LCD

NOTE:

pushbuttons are to be replaced by IR sensors and comparators

Coal mine detection robot

It is mandatory to check the coal mine weather conditions prior to workers entry. If the weather conditions are normal then workers can enter , otherwise they will not go inside the mine. To check the weather conditions all over the mine we will send one robot which will monitor CO (carbon monoxide) in the mine, temperature and light intensity in the mine. After reading each parameter it will compare with threshold readings and produces output depending the readings taken. This robot is also an obstacle avoidance robot, it uses IR sensors to control its movement in the mine.

here is the flow chart

to download C-code
  to see video output

Schematic Diagram:
case'1':  when the light intensity is less in the mine
pulse width to the light is 0.1sec. and obstacle detected on left side. robot moving to right side 
                          A Reference book to learn about robots in hazardous environments here

case'2': when light intensity is less, high temperature and CO gas exceeded in the mine
 pulse width to the light is varying 0.1s, 0.25s and 0.5 sec to indicate 3 parameters are not in normal condition. and no obstacle detected

NOTE: 
push button at P1.3 has to be replaced by CO Gas sensor,
push buttons at P1.4 and P1.4 are to be replaced by IR sensors.  
Green LED will be replaced by Buzzer.
Threshold values may vary in practical  

line follower robot using 8051

This robot can follow black line on the floor. It is designed using micro controller and IR sensors.

  to download C-code

  to see video output

Here is the simple schematic diagram

case'1': when right motor crossed black line

  

case'2': normal operation

 IR sensor operation

NOTE:

   push buttons should be replaced by IR senors and comparator circuits

Line follower robot without microcontroller

Here is a robot which will follow the black line on the floor. This is controlled on the basis of IR sensors. This doesn't use any micro controller and microprogram.
This is the logic circuit to control the robot operations

  llogic reduction using k-map
  to see video output

reduced logic

IR sensor operation

NOTE: here the push buttons are replaced by IR sensors and comparator circuits.