In this project we show that how we control the movement of any small robot with the help of mobile phone. By using this logic we not only control the movement of vehicle but also switch on/off other accessories on robot.
In autocleaner we will make a wood arm and will fix that arm on GSM robot using a DC motor.
Our project is to be divided into few parts.
Autocleaner
Vehicle control.
Supply circuit
GSM control.
CONCEPT:
In this project we use smart logic and control system of embedded system by using microcontroller. In this project we use ic 89c51 as a main processor.. microcontroller sense the signal and drive the motor of the robotic vehicle. .
Ist circuit is ic 8870. IC 8870 is a bcd to dtmf decoder. So our first part of the circuit is our dtmf decoder. This part is very much necessary, without using this part is not possible to interact with the mobile phone or dtmf based any phone. Whenever we press any switch from the transmitter phone then transmitter transmit some signal as per the switch press. So on every press switch there is a different signal
Frequency |
1209 |
1336 |
1477 |
1633 |
697 |
1 |
2 |
3 |
A |
770 |
4 |
5 |
6 |
B |
852 |
7 |
8 |
9 |
C |
941 |
* |
0 |
# |
D |
Output of the dtmf decoder is bcd.ur next circuit is how to convert bcd signal into decimal signal. In this project we use ic 74154 as a bcd to decimal decoder circuit. IC 74154 converts the bcd signal into decimal signal . Output of the 74154 is active low.
Output of the 74154 is connected to the 89c2051 microcontroller. Ic 89c2051 microcontroller basically drive the motor for forward and reverse movement.
Output of the microcontroller is connected to the optocoupler circuit. Here in this project we use ic pc 817 as a optocoupler to interface the microcontroller to small slow speed dc gear motor. One gear motor drive the vehicle and second gear motor change the front wheel of vehicle..
Power supply circuit.In this project we use 9 volt battery to drive the vehicle. One 9 volt battery for the microcontroller circuit. Second 9 volt battery drive the motor driver circuit . Here in the project we one 5 volt regulator circuit. Output of the 9 volt dc is converted into 5 volt dc by using 7805 regulator circuit. Ic 7805 regulator converts the 9 volt dc into 5 volt dc with the help of the 5 volt regulator 7805.
VEHICLE CONTROL.In this project we use two small gear dc motor for drive the small robot. One motor for the back wheel and one motor for the front wheel. Back motor drive the both tyre at a time and front motor control the direction of the vehicle . Here we use powerful gear dc motor instead of stepper motor. Stepper is not suitable for the drive the vehicle. Stepper motor is suitable for positioning sensor but gear motor is suitable for the vehicle drive.
Motors:To make the robots mobile we need to have motors and the control circuitry that could control the motors. There are different kinds of motors available for different application.
1. DC motor
2. Stepper motor
3. Servo motor
IC 8870 . DTMF DECODER. We use this ic in our project for mobile interface. By using this ic we decode the dtmf pulses from the mobile phone through hands free and by using this ic we convert this pulses in to bcd signal.
IC 74154. ic 74154 ic basically convert the bcd signal in decimal signal for further use with the microcontroller. IC 74154 convert the 4 bit data in to 16 bit output. Here in this project there is no use of 16 output, so we use only 4 output.
89C2051 MICRCONTROLLER.89C2051 MICROCONTROLLER. Is a 20 pin version of 51 family,. Program written for this controller is same for the 8051 controller. In this controller there is total 15 input and output pins. For controlling the process control.
OPTOCOUPLER ( PC 817) In this project we use optocoupler to provide a electrical isolation between process control circuit and motor drive circuit. In this project we use separate supply for processor and control circuit. Pc 817 is 4 pin ic. In this coupler two pin is input and two pin is output.
CRYSTAL. In this project we use two crystal. One for the dtmf decoder and second with the microcontroller Main use of the crystal is to provide a external frequency for the internal oscillator. With the dtmf decoder we use crystal 3.58 Mhz and with the microcontroller we use 12 Mhz crystal.
DC MOTOR. We use slow speed dc motor to drive the movement of vehicle. In this project we use two dc motor. One for the drive the vehicle and second motor to change the direction of the vehicle.
H BRIDGE LOGIC: H bridge logic is basically provide a forward and reverse logic to the motor.