The Intelligent Wireless Video Camera described in this paper is designed using wireless video monitoring system, for detecting the presence of a person who is inside the restricted zone. This type of automatic wireless video monitors is quite suitable for the isolated restricted zones, where the tight security is required.The principle of remote sensing is utilized in this, to detect the presence of any person who is very near to reference point with in the zone.
A video camera collects the images from the reference points and then converts into electronic signals. The collected images are converted from visible light into invisible
electronic signals inside a solid-state imager. These signals are transmitted to the monitor, Each reference point is arranged with two infrared LED’s and one lamp. This arrangement is made to detect the presence of a person who is near the reference point. The reference point is nothing but restricted area, when any person comes near to any reference point, then immediately that particular reference point output will become high and this high signal is fed to the computer. Now the computer energizes that particular reference point lamp and rotates the video camera towards that reference point for collecting the images at that particular reference point. To rotate the video camera towards interrupted reference point, stepper motor is used
Intelligent Wireless Video Camera
The video surveillance unit is designed for the widest possible viewing range and portability. The unit consists of a Stepper Motor, which drives the camera towards reference points automatically by the computer and a transmitter transmits the images collected by the camera to a distant end. Thus a automatic controlled wireless camera is very useful for surveillance of places where the particular location makes it inconvenient or impractical for a wired operation of the unit. The robotic action made by the stepper motor is attached to the camera allows surveillance of maximum area with one single camera.
Such setup can be very flexible to the user and can save valuable company resources. There are several types of security systems existed in the Market; one of the most common security systems is CCTV (Closed Circuit Television). The CCTV consists Video Surveillance Camera used as security-monitoring device plays a major roll in security systems. One reason for this is the fact that a picture is worth then a thousand words. This is especially true in a court of law where an eyewitness is required who can place the criminal at the scene of a crime.
CCTV systems are also helpful in the residential security Market. They allow homeowners to see their callers, thus establishing their identity before they open an outside entrance door. This is an important feature too, because other wise, they might open their door to a criminal.
The Infrared sensing circuit consists of two infrared LED's for transmitting the signal as well as receiving the signal. The signal transmitted by the transmitting LED omits the signal in a line like laser beam, the radiated signal from the transmitting LED is invisible and harmless. Whenever the human body interrupts the transmitting signal, there the signal is reflected and this reflected signal is received by the infrared receiving LED.
Stepper Motor Drive Circuit :
The stepper motor used in this is having four windings and these windings are energized one after another in a sequence according to the code produced by the computer through motor drive circuit. This motor rotates in step wise and the step angle is 1.8 0 . Varying the pulse rate can vary the speed of the motor. The pulses are produced by the computer can be controlled through the program by which motor speed can be varied. The stepper motor used in this project work is capable to drive up to 3kg load.
Each reference point is arranged with two infrared sensors and both the sensors are arranged side by side within the distance of one inch approximately and both are directed towards the space with the zone. The energization sequence for the forward and backward movements of the stepper motor is fed from computer with the help of software written in 'C' language.
The ratings of the motor employed are 12V dc 4-coil. The driving circuit of the motor is designed using BC 547 (low power Transistor) and 2N5296 (Medium power Transistor). These two transistors are configured in emitter following mode for amplifying the current rating. The motor winding when it is energized, it consumes 350 mA approximately.