Working

The most important tools for the working of AUTOMATIC GESTURE CONTROLLED ROBOT are the human gestures and image processing of these gestures. These gestures are used to direct robot according to our need. Image Processing has huge computational requirements, and it is not possible to run an image processing code directly on a small microcontroller. Hence, for our purpose, the simplest approach would be to run the code on a computer, which has a webcam connected to it to take the images, and the robot is controlled by the computer via parallel port. The code is written in software that provides the tools for acquiring images, analysing the content in the images and deriving conclusions. MATLAB is one of the much such software available which provide the platform for performing these tasks. An image (or any other data like sound, etc.) can be converted to a matrix and then various operations can be performed on it to get the desired results and values. Image processing is quite a vast field to deal with. We can identify colours, intensity, edges, texture or pattern in an image. In this project we would be restricting ourselves to detecting colours (using RGB values) only.

                       The output of a computer i.e. the image processing results of MATLAB is fed to the DB-25 parallel port which interfaces the computer with our gesture controlled robot. DB-25 is 25 pin port, divided in ratio of 13:12, 4 pins out of these pins receive input from PC and transfer that input to four 4N35-optocouplers as shown in Fig. 17. These optocouplers act as isolator and voltage regulator between DB-25 parallel port and microcontroller. The optocoupler application or function in the circuit is to:

Ø  Monitor high voltage

Ø  Output voltage sampling for regulation

Ø  System control micro for power on/off

 If the optocoupler IC breakdown, it will cause the equipment to have low power, blink, no power, erratic power and even power shut down once switch on the equipment.

                         Output from the four optocouplers goes to port B of microcontroller ATMEGA-8. It is a 28 pin controller that controls the movement of robot. Port D of the controller carries output from the controller to L293D H-Bridge Motor controller. The L293D is designed to provide bidirectional drive currents of up to 600-mA at voltages from 4.5 V to 36 V. The output of microcontroller is generally low and motor operates on high voltage and current values. L293D provides necessary voltage and current for running of D.C motor running at 60 rpm. Finally output of L293D motor controller goes to two D.C motor that moves the robot in four directions- left, right, clockwise, and anticlockwise.

ROBOT MOVEMENT	LEFT D.C. MOTOR MOVEMENT	RIGHT D.C. MOTOR MOVEMENT
Forward	Clockwise	Clockwise
Reverse	Anti- Clockwise	Anti- Clockwise
Left Turn	Anti- Clockwise	Clockwise
Right Turn	Clockwise	Anti- Clockwise
Stationary	OFF	OFF