Bluetooth to RF Transmitter

This is a set of modules that can receive information over RF; this data is transmitted from a base transmitter which is connected to Bluetooth module that can receive data from your phone. Essentially this converts the input from the phone to RF signals that can be transmitted over a short distance to control various components.

Diagram1   This picture here shows the transmitter module and the receiver module. The transmitter consists of an ATTiny85, Bluetooth Module, and a TX RF module. The Receiver has only the ATTiny85, and a RX RF module. The transmitter is designed to be a central unit where the information is taken from the user via Bluetooth and is then relayed to the receivers over RF. Having a central transmitter allows us to have as many receivers as we want without the signal being affected in any way. These RF links are not so powerful, I was able to get about 31FT of transmission from the Central transmitter to the Receiver station I made. This Receiver station can be seen on the picture below. Here I have two sets of receiver modules being powered by the same 3.7 LI-PO battery. I have the LED’s on these modules turn ON/OFF, 0 turns one off, but turns on the other, etc. This allowed me to test on having more than one receiver module.

Diagram2Module Circuits

ReceiverTransmitterReceiver Module Circuit                                          Transmitter Module circuit

The Lawn Mower

The Lawn Mower.
The Lawn Mower

“The Lawn Mower” is a RC Bluetooth car that I made for one of my CET classes. The car runs using a 9 volt battery for supply, two 5 volt regulators that feed the ATTiny85, Servo, Bluetooth Module, LN298N H-bridge IC, as well as the back dual DC motors.

The brains come from the ATTiny85 micro controller from ATMEL, it has 8 pins 5 which are usable. This allows me to use two for the LN298N to go back and forth, one for the servo, and two for the TX and RX on the Bluetooth Module.

ATtiny85Here you can see how the ATTiny85 is configured.

circuitThis is the circuit for the car itself.

If you want to see it in action you can watch it here.