ABSTRACT:

The main aim of the project is to design a versatile device that can control stepper motor by using RF technology of wireless communication. This device can be used to control the speed and direction of the stepper motor.

The RF modules used here are STT-433 MHz Transmitter along with an RF encoder HT12E, STR-433 MHz Receiver along with an RF decoder HT12D.

In this project first microcontroller is connected to RF transmitter through HT12 E encoder. Some basic sensors like water sensor, smoke sensor and vibration sensor are connected to microcontroller. At other end second microcontroller is connected to RF receiver through HT12D decoder. This will always in receiving mode to receive all data from sensors. These sensors can detect water level, smoke existence and vibration occurrence in coal mines. When any of these parameters are sensed by microcontroller it gives buzzer sound and transmit to RF receiver. Second microcontroller will displays sensors status on16X2 LCD display.

This project uses regulated 5V, 500mA power supply. Unregulated 12V DC is used for relay. 7805 three terminal voltage regulator is used for voltage regulation. Full wave bridge rectifier is used to rectify the ac output of secondary of 230/12V step down transformer.

 

TECHNICAL SPECIFICATIONS:

HARDWARE:

Micro controller         :           AT89S52

Crystal                        :           11.0592 MHz

LCD                            :           HD44780

RF transmitter             :           STT-433MHZ

RF receiver                 :           STT-433MHZ

RF encoder                 :           HT12E

RF decoder                 :           HT12D

Power supply

Transformer                :           12V step down 

Filter                           :           1000uf/25V

Voltage Regulator      :           7805

SOFTWARE:

Keil micro vision

proteus

UC flash

APPLICATIONS:

• Industrial applications
• Mining applications