Remote Operated Robotic Vehicle

Remote Operated Robotic Vehicle Using RF Module

About RF Module:

In generally, the wireless systems designer has two overriding constraints: it must operate over a certain distance and transfer a certain amount of information within a data rate. The RF modules are very small in dimension and have a wide operating voltage range i,e 3V to 12V.

Basically the RF modules are 433 MHz RF transmitter and receiver modules. The transmitter draws no power when transmitting logic zero while fully suppressing the carrier frequency thus consume significantly low power in battery operation. When logic one is sent carrier is fully on to about 4.5mA with a 3volts power supply. The data is sent serially from the transmitter which is received by the tuned receiver. Transmitter and the receiver are duly interfaced to two microcontrollers for data transfer.

Features:

·         Receiver frequency 433MHz

·         Receiver typical frequency 105Dbm

·         Receiver supply current 3.5mA

·         Low power consumption

·         Receiver operating voltage 5v

·         Transmitter frequency range 433.92MHz

·         Transmitter supply voltage 3v~6v

·         Transmitter output power 4v~12v

Applications:

·         Wireless security systems

·         Car alarm systems

·         Remote controls.

·         Sensor reporting

·         Automation systems

Working of Remote Operated Robotic Vehicle:

The robot is a moving vehicle remotely controlled by one transmitting unit and a receiving unit for its moment. In this we used HT12E encoder which converts 4 bit data to serial output. As explained above this is then fed to the RF module for transmitting the same to be received by the receiver. The RF module the output is fed to HT12D the serial decoder IC, the output of which is fed to microcontroller pin 1 to 4. The transmitting end microcontroller is connected to a set of pushbutton switches to its port 3 of 20 pin microcontroller AT89C2051. Thus while a particular button is pressed the program is executed to deliver corresponding 4-bit data which are then transmitted serially at port 1 as explained above. The data so received at the receiver end of port 1 of the Microcontroller.

A laser light is driven by transistor Q1 from the output of microcontroller pin 15, while the robotic vehicle is manourved to the location by operating the left, right, forward and backward button etc. after it reaches the site the laser mounted on it takes position to throw the beam by operating specific action button.

RF Transmitter Circuit:

RF Receiver Circuit: