16-03-2011, 04:57 PM
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Digital Pulse Counter & Tachometer
DESCRIPTION :
The main aim of this project is to calculate the speed of the motor. In earlier days, speed of the motor was calculated by using contact tachometer, here only limited speed can be calculated, and the accurate reading cannot be obtained and display the calculated value in analog form, this analog form display is difficult to understand. So in this project we can overcome these above problems, as here we are using here contact less tachometer. From this tachometer we can calculate the speed of the motor to a large extent. And accurate reading is obtained; calculated value will be in the form of digital, which is easy to understand.
TECHNOLGY :
This project uses State-of-the Art Sensing Technology.
The idea behind most digital counting device, frequency meters and tachometers, is a micro-controller, used to count the pulses coming from a sensor or other device.
In the case of this tachometer, the counted pluses will come from proximity sensor, which will detect any reflective element passing infront of it, and thus, will give an output pulse for each and every rotation of the shaft, as show in the picture. Those pulses will be fed to the microcontroller and counted.
WORKING :
This project is mainly designed to calculate the speed of the motor, this is done by using microcontroller and photo sensor. The photo sensor is located near the motor. Whenever the motor completes one rotation the photo sensor senses this and generates the pulse. This pulse is given to the Microcontroller. Microcontroller works like a counter. So whenever microcontroller gets a pulse from the photo sensor it Increments the counter value. The counted value is displayed in the LCD which is in digital form.
EXAMPLE :
In bikes (Speedometer) & Cars
OUR CHALLANGING WORK IN THIS PROJECT:
Writing the Code for the Microcontroller using Embedded ‘C’ for 8051
% OF SOFTWARE & HARDWARE :
Embedded C – 40%
Microcontroller Hardware – 60%
FUTURE ENHANSEMENT :
Actual reading value display digital form
It uses digital display so avoids alignment problem
MAIN COMPONENTS USED :
5 V DC Power Supply
ATMEL AT89S52 Microcontroller
Analog to Digital Converter ( ADC – 0808 )
LCD 16*2 Alpha Numeric
Buzzer – Frequency ( 1 to 18 KHz, 5V – 12V DC )
DESCRIPTION OF MAIN BLOCKS :
Micro Controller
The AT89S52 is a low-power, high-performance CMOS 8-bit microcontroller with 8K bytes of in-system programmable Flash memory. The device is manufactured using Atmel’s high-density nonvolatile memory technology and is compatible with the industry- standard 80C51 instruction set and pin out.
Features
• 8K Bytes of In-System Programmable (ISP) Flash Memory
• Endurance: 1000 Write/Erase Cycles
• 4.0V to 5.5V Operating Range
• 256 x 8-bit Internal RAM
• 32 Programmable I/O Lines
• Full Duplex UART Serial Channel
• Fully Static Operation : 0 Hz to 33 MHz