Arduino Tachometer or RPM Meter Circuit

Introduction:

                   This project, named "Arduino Tachometer or RPM Meter," utilizes an Arduino board to measure the RPM of any motor. The project employs an IR module, which includes both an IR transmitter and receiver, to detect the motor's RPM.

Working:

Program Upload:

• The Arduino board operates based on the uploaded program. Once the program is uploaded, the LCD display initially shows a predefined name and "0" RPM.

IR Module Detection:

• The IR module detects the movement of a running object, particularly a black-colored section on the motor's pulley, and sends a digital input signal to the Arduino.

Signal Processing:

• The Arduino decodes this digital input and converts it into an analog output.

Display:

• The analog output is then sent to the LCD display through the I2C module, which shows the RPM of the running motor.

Part List:

1)  Arduino Board (UNO or NANO) =1

2)  I2C Module =1

3)  Data Cable for Arduino =1

4)  IR Module =1

5)  Bread Board or Zero Board =1

6)  Power Supply =1

7)  Some Male to Female Jumper Wires

Circuit Diagram:

Detailed Circuit Connection Explanation for Arduino Tachometer (RPM Meter)

Components Overview

1. Arduino Nano: The central microcontroller for processing and displaying RPM data.
2. IR Module: Includes an IR LED and a photodiode to detect motor rotation.
3. LM358 Operational Amplifier: Amplifies the signal from the photodiode.
4. 16x2 LCD with I2C Module: Displays the RPM readings.
5. Various Resistors and Capacitors: For signal conditioning and stabilization.

Step-by-Step Connection

1. IR Module Connections:

   • IR LED (TX1):
     • Connect the anode of the IR LED to a 1kΩ resistor (R4).
     • The other end of the 1kΩ resistor is connected to the +5V power supply.
     • Connect the cathode of the IR LED to ground (GND).
   • Photodiode (D1):
     • Connect the anode of the photodiode to a 10kΩ resistor (R3) and ground.
     • Connect the cathode of the photodiode to a 220Ω resistor (R2) and the non-inverting input (pin 3) of the LM358 operational amplifier.

2. Signal Conditioning Using LM358:

   • Operational Amplifier (U1, LM358):
     • Connect the inverting input (pin 2) of the LM358 to a voltage divider formed by a 10kΩ potentiometer (RP1). The other side of the potentiometer is connected between +5V and ground.
     • Connect the output (pin 1) of the LM358 to a 330Ω resistor (R1).
     • The other end of the 330Ω resistor is connected to the anode of an LED (LED1) for visual indication and to one of the digital input pins on the Arduino Nano (D12).
     • Connect the cathode of the LED to ground.
   • Power the LM358 by connecting pin 4 to ground and pin 8 to +5V.

3. Arduino Nano Connections:

   • Power Supply:
     • Connect VIN to a 6-12V power source.
     • Connect the GND pin to the ground.
     • The +5V pin on the Arduino provides power to the IR module and operational amplifier circuit.
   • Signal Input:
     • Connect the output of the LM358 (through the 330Ω resistor and LED) to digital pin D12 on the Arduino Nano.

4. LCD with I2C Module Connections:

   • Connect the SDA (data line) of the I2C module to A4 on the Arduino Nano.
   • Connect the SCL (clock line) of the I2C module to A5 on the Arduino Nano.
   • Connect the VCC pin of the I2C module to the +5V pin on the Arduino.
   • Connect the GND pin of the I2C module to the ground.

Working Principle

1. IR Module Functionality:

   • The IR LED emits infrared light continuously.
   • When a rotating object (like a black-colored section on a pulley) passes in front of the photodiode, it either reflects or blocks the IR light.
   • The photodiode detects the changes in IR light intensity and generates a corresponding electrical signal.

2. Signal Processing with LM358:

   • The signal from the photodiode is weak and requires amplification.
   • The LM358 operational amplifier boosts this signal. The potentiometer (RP1) sets a reference voltage to compare the incoming signal from the photodiode.
   • The output from the LM358 is a clean digital pulse that indicates the detection of a passing object.

3. Arduino Nano Processing:

   • The Arduino Nano receives the digital pulses on pin D12.
   • The Arduino counts these pulses over a specific period (e.g., one second) to calculate the RPM.
   • The RPM value is then processed and sent to the LCD display via the I2C module.

4. Displaying RPM on LCD:

   • The 16x2 LCD, driven by the I2C module, displays the calculated RPM.
   • The I2C module simplifies the connection by reducing the number of pins required for the LCD interface (only SDA and SCL are needed).

Schematic Summary

• IR LED: Powered by +5V through a 1kΩ resistor.
• Photodiode: Connected to the non-inverting input of the LM358.
• LM358: Amplifies the photodiode signal, output connected to Arduino D12.
• Arduino Nano: Processes signal, calculates RPM, and communicates with LCD.
• I2C LCD: Displays RPM value using SDA and SCL lines from Arduino.

By following this detailed guide, you can successfully build an Arduino-based tachometer for measuring the RPM of motors with high accuracy.

Uses of This Project:                 

    This project is useful for accurately measuring the speed of any motor. It can be employed in various applications, including:

• Industrial motor speed monitoring
• Laboratory experiments
• DIY projects and hobbyist applications

By following these instructions and referring to the circuit diagram, you can build a functional Arduino Tachometer (RPM Meter) to measure the rotational speed of motors.

                 

Click Here to Download the Project’s Code:

 

                                                               

Click Here to See YouTube Video for This Project:

           

           

Thanks For Visiting