The tutorial com from http://www.micahcarrick.com/05-27-2006/failurebot-line-following-robot.html
Here the robot preview:

Microcontroller ATMega8
Sensor: 5 pieces phototransistor
Motor: Lynxmotion motor
Programming language:
Download tutorial (mechanics, schematics, source code)

The L297 integrates all the control circuitry required to control bipolar and unipolar stepper motors. Used with a dual bridge driver such as the L298N forms a complete microprocessor-to-bipolar stepper motor interface. Unipolar stepper motor can be driven with an L297 plus a quad darlington array. This note describes the operation of the circuit and shows how it is used.

Download Sharp GP2D12 Analog Distance Sensor Manual and Tutorial
SharpGP2D12Snrs.pdf

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

Here the tutorial how to make hexapod robot using 3 servo motors:
Download Hexapod Robot Tutorial:
hexapod.pdf
Download The video:
hexapod video.wmv

Download robotics servo tutorial for student guide from parallax:
Download here:
robotics_servo.pdf
PIC18CXXX/PIC16CXXX DC Servomotor Application Note:
Download the tutorial:
DC servomotor application of PIC.pdf

Another tutorial how to get start with the AVR microcontroller:
Just download the file here:
getting_started_with_the_AVR.pdf

Need reference for your fire fighting robot project..?
Here some useful reports of fire fighting robot project.: