RF Controlled Rover
Created: Dec 18, 2014
No description available.
This project is a mini land rover that can be controlled remotely using Radio frequency (RF) communication. A pair of RF receiver and transmitter IC are used for this device. The application of this device is very wide; from a simple toy to a military gadget used for operations. The mini rover is useful for its portability and the ability to enter places not reachable for humans.
The RWS and TWS 434 TX/RX pair and the serial communication that is built into the PICBasic programming language for PIC16F84 works well. The programming is written in Basic and uses pre made serial communication routines. Position the Potentiometer in the joystick using the PICBasic 'POT' command and put the result in memory location 'B0'. Using the 'SEROUT' command, set the contents of 'B0' to pin 6 of the TWS 434 transmitter. On the receiver end, use the 'SERIN' command and read the incoming data from pin 3 on the RWS 434 and put the result in 'B0'. The value in 'B0' directly correlates to joystick position; above 150 is right, below 106 is left, and in between is center. The deadzone can be defined using these numbers.
From the numbers transmitted we can determine the direction (left, right, etc). With this information speed control can be introduced, the further the number from 128 (center) the more speed is applied. In this project, PORTA pin is used on of the PIC16F84 to control the motor direction and no speed control is used. Since our serial data is 10 bits in length (1 start bit, 8 data bits, 1 stop bit) we can send 960 commands to the receiving PIC16F84 in one second. The antennas made for 900Mhz cordless telephones got a range of 350 feet outdoor, and when a boosted transmitter power slightly past 12 volts (not recommended), the distance of 500 feet is achieved.