In order to be able to build a closed loop controller, you need some mean of gaining information about the rotation of the shaft like the number of revolutions executed per second, or even the precise angle of the shaft. This source of information about the shaft of the motor is called “feed-back” because it sends back information from the controlled actuator to the controller.
LASER BASED SPEED SENSOR
The methodology of our project is shown in the block diagram in fig 1.1 .
Fig 1.1: Block Diagram of DC Motor Speed Control 1. INPUTS: User defined or user desirable speed are fed to the MCU block or microcontrller through numerical keyboard. 2. MCU: The main controlling unit which takes as well as sends signal to control the speed of the motor and displays the speed as well. 3. MOTOR CONTROLLER: It takes the reference signal from MCU and convert it into required voltage. 4. MOTOR DRIVER: The required power to drive the motor will be fed by the motor driver. 5. MOTOR: The motor now runs at the desired speed as given. 6. LASER BASED SPEED SENSOR: Here laser speed sensor circuit is used to drive the speed of the motor and feeds the equivalent signal to the MCU. 7. LCD DISPLAY: Displays the obtained speed.
1.3 CIRCUIT DIAGRAM:
1.4 WORK PLAN: In this semester we are planning to design the optical tachometer and learn the basic operation of the microcontroller. START
Doing some literature survey and studying the project
Design the block diagram of the whole circuit
Design the circuitry for each blocks
Testing the hardware for the blocks
Make changes to the circuitry.
Is the hardware working properly
Test the changes
Integrating different block together
Testing the assembled...