Projects On Embedded Systems

Now a days saving power is much essential in an industrial applications. PWM is a modern trend for controlling the speed of Industrial motors which reduces the power loss as heat.A dual timer is accomplished with microcontroller so as to generate PWM. The pulse width is controlled by keypad. The output of microcontroller is optically coupled to the motor driving unit( thyristors). Thus this unit allows to run a motor with five speed levels, which includes halt condition. The optical coupling is done here to prevent AC return from motor. Thus this project is much better than transistorized power control.

The RF Microcontroller based transmitter and receiver through wireless can control many home appliances efficiently. In our home sometimes we forget to switch off the electronic equipments,which in turn huge electrical losses can occur. To overcome this drawback we adopt wireless home automation.

This is invoked by RF Microcontroller based transmitter and receiver. By this we can control the devices, which have more number of devices connected in industries. We can control
much electrical equipment at a remote place.

This software controls the speed of a DC motor from PC’s parallel port. The PC uses a software program to control the speed of the motor. The motor is connected to the PC through an interface circuit. The interface circuits of 1-to 8 decoder IC, ex invertors, resistor and motor driver transistor.

Initially, when the motor is ‘off‘the program prompt you to press ‘Enter’ key to start the motor. Once you to press the key the motor start running full speed. After a few second, the program asks you to press any key from keyboard to go the next screen for controlling the speed and also for exiting from the program. For increasing the speed enter choice1 and press ‘Enter’ key and for decreasing the speed enter choice 2 and press‘Enter’ key. This action changes the speed by one step at a time and the message ‘Speed decreases” or “Speed increased” is displayed on the screen. To go to the main menu again press ‘Enter’ key.

Easy to use stepper motor controller, for bipolar or dc motors. Uses the L298N IC from SGS-THOMSON as the driver IC, incorporates heavy-duty heat sink. Standard logic control, with logic supply of 5Vdc. Motor supply can be up to 50Vdc and 4A. Standard polarized connectors are provided for all connections.

Radio Frequency Identification (RFID) systems use radio frequency to identify, locate and track people, assets, and animals. Passive RFID systems are composed of three components –a reader (interrogator), passive tag and host computer. The tag is composed of an antenna coil and a silicon chip that includes basic modulation circuitry and non-volatile memory.The tag is energized by a time-varying electromagnetic radio frequency (RF) wave that is transmitted by the reader. This RF signal is called a carrier signal.When the RF field passes through an antenna coil, there is an AC voltage generated across the coil.This voltage is rectified to result in a DC voltage for the device operation. The device becomes functional when the DC voltage reaches a certain level. The information stored in the device is transmitted back to the reader. This is called backscattering.By detecting the backscattering signal, the infor mation stored in the device can be fully identified.

Because of its simplicity, the passive RFID system has been used for many years in various RF remote sensing applications. In recent years, there have been dramatic increases in application demands. In most cases,each application uses a unique packaging form factor,communication protocol,frequency,etc.

This Robot is Capable of Monitoring the Distance of an Object to which it is approaching. It consists of a RF Remote Controller With Trans-reception Frequency 49mhz and an IR Distance Monitoring Unit. The Distance is displayed in a 7 Segment Display. The Project utilizes a PIC Microcontroller for Processing and some External Analog Components for Controlling Over Remote. This is achieved using PC via printer port.

In this project we can control external devices using mobile phones. The DTMF Technology is used to Control Devices. In this project we need two phone connections one is the land line and another one is the mobile phone connection, the user should dial the land line number to establish a connection between the landline and the mobile after that the user should dial the device number through the mobile phone the gadget automatically detects the ring and automatically switches on/off the external devices the famous atmel 89c52 microcontroller is used in this project the relays are used for device controlling.

The Metal Sensor used here is of a low frequency oscillator. The project uses two similar low frequency RF Oscillator which is of air core inductor type of which one Oscillator is known as search coil while the other as the reference coil, the output frequency of both Oscillator in the absence of metal is same, while in the presence of an metal piece the output of the search coil oscillator automatically falls down the microcontroller compares the output of the two coils and warns about the presence of metal and also an automatic dialer can also be fitted so that the unit automatically calls the police.