Sunday 16 February 2014

Automatic Passenger Controller in Buses



Automatic Passenger Controller  in Buses


The automatic passenger controller is a system which controls the number of passengers inside the bus. This system counts the passengers  enterd the bus and leaves the bus. If the passenger count reaches the maximum permissible number the the door automatically closed. It opens only after the passenger number decreases.

Block Diagram




















Microcontroller
            PIC is a family of Harvard architecture microcontrollers made by Microchip Technology. The name PIC initially referred to "Peripheral Interface Controller". Mid-Range devices feature a 14-bit program word architecture and are available in 8 to 64-pin packages. These microcontrollers provide 1.8-5.5V operation, speeds up to 20 MHz, interrupt handling and an 8-level deep stack. These devices are available in various peripheral and memory configurations and feature serial analog and digital peripherals.

LCD
            This is a basic 16 character by 2 line display. Black text on Green background. Utilizes the extremely common HD44780 parallel interface chip set. It will need minimum 6 general I/O pins to interface to this LCD screen. Includes LED back light. This will work in 4 bit and 8 bit mode.

Motor Driver
            To make a motor operate, we have to pass a suitable pull-in and holding current (DC) through its terminals. And generally motor  field coils are designed to operate from a particular supply voltage often 12V or 5V, in the case of many of the small motors used for electronics work. In each case the coil has a resistance which will draw the right pull-in and holding currents when its connected to that supply voltage. To provide this current,motor driving circuits are used.

Stepper Motor
            A stepper motor (or step motor) is a brush less, synchronous electric motor that can divide a full rotation into a large number of steps. The motor's position can be controlled precisely without any feedback mechanism.

Power Supply
            In mains-supplied electronic systems the AC input voltage must be converted into a DC
voltage with the right value and degree of stabilization. The ac from the transformer secondary is
rectified by a bridge rectifier and filtered by the capacitor. A Linear voltage regulators produce regulated output voltage.








Intelligent Load Shedding System



Intelligent Load Shedding  System

This system continuously monitor the connected load in a industry and disconnect if the load go above the preset level. Here the total load is divided three categories. The authorized person may set connecting load by using keypad. If the connected load go above the previously set value it will warn 30sec to reduce the connected load otherwise the system disconnect the load from the mains one by one. The user can connect the load using the keypad attached to this device or the device will automatically connect the load after a preset interval.

















Microcontroller
            PIC is a family of Harvard architecture microcontrollers made by Microchip Technology. The name PIC initially referred to "Peripheral Interface Controller". Mid-Range devices feature a 14-bit program word architecture and are available in 8 to 64-pin packages. These microcontrollers provide 1.8-5.5V operation, speeds up to 20 MHz, interrupt handling and an 8-level deep stack. These devices are available in various peripheral and memory configurations and feature serial analog and digital peripherals.



Load
            Connected load.

Current Sensor and Signal Conditioner
            Current sensing transformers are used in applications where one needs to detect or measure AC-currents. Current transformers (abbreviated as CT) are current sensors. They reduce alternating high current circulating through cables in electrical installations. The secondary winding supplies AC proportional to the current conducted through the primary

Voltage Sensor and Signal Conditioner
            Voltage Sensing Transformers, sample high voltage through the primary and deliver an exact replica to the secondary at a lower voltage.

LCD
            This is a basic 16 character by 2 line display. Black text on Green background. Utilizes the extremely common HD44780 parallel interface chip set. It will need minimum 6 general I/O pins to interface to this LCD screen. Includes LED back light. This will work in 4 bit and 8 bit mode.

Keypad
            For entering preset values, setting cut off limits etc

Buzzer
            Which is used for producing audio alarm to indicate over load.

Relays
            Relays are electro-mechanical components which allow a low-power circuit to switch a relatively high current on and off, or to control signal that must be electrically isolated from the controlling circuit itself.

RTC
            A real-time clock (RTC) is a clock (most often in the form of an integrated circuit) that keeps track of the current time. RTCs often have an alternate source of power, so they can continue to keep time while the primary source of power is off or unavailable. This alternate source of power is normally a battery .

Power supply
            In mains-supplied electronic systems the AC input voltage must be converted into a DC
voltage with the right value and degree of stabilization. The ac from the transformer secondary is
rectified by a bridge rectifier and filtered by the capacitor. A Linear voltage regulators produce regulated output voltage.