Build your own line follower / line tracker robot…!

Microcontroller : Atmel ATMega8535
Sensor: 6 photodioda sensor
Motor driver : L298 dual driver (up to 1A of electric current)

Download ping parallax ultrasonic distance sensor datasheet, schematic and program code sample:
» Download Link

Many fire fighting robot competition in the world with diffrerent mission but have similiar field…
Here some useful reports of fire fighting robot project.:

This article will show you how to control the LCD Display become a digital clock.  This experiment use LCD Character 2 x 16 module for showing the analog characters.

==============================================

Step 1st
Build the circuit as shown in figure 5.2.3. Remember, that all we want to do with this lesson displays digital clock with display on LCD Character 2 x 16.

Figure 5.2.3. Digital clock with timer 0 interrupt

Step 2nd
In this step, you must tipe the assembly program to make your Timer get action, we assume that you have already known the editor, we used MIDE-51 to edit the program.

This tutorial will helps you how the PWM works. You will learn what is PWM, the usage of PWM also how to program a DC Motor with PWM. Some Robots need to control the motor speed for its to work. Just use PWM system and you will get your motor’s speed adjustable…

Basic PWM

One of the easiest ways of generating an analog voltage from a digital value is by pulse-width modulation ( PWM ). I PWM a high frequency square wave is generated as a digital output. For example, a port bit continuously swiched on and off at a reltive high frequency. The signal is fed to a low pass filter. The voltage at the otuput of filter is equal to ther Roo Mean Squeare ( RMS ) of the squeare wave signal. The RMS of the square wave signal may then be varied by changing the duty cycle of the signal. A cycle is initiated by a low to high transition of the signal and terminates at the next such transition. During one cycle if the time the signal stays high is equal to the time the signal stays low, then the duty cycle is said to be 50 percent.

Figure 1. Duty Cycle 30 %

The following circuit shows a DAC constructed with PWM. The Program controls the speed of a DC motor by pulse width modulation ( PWM ). Bit P3.0 Drives a switching transistor as shown in the circuit diagram. Motor is swiched on for a period of time, and then off. The fraction of time the motor is on is call the duty cycle.