Ads by ArduinoGetStarted.com
Arduino - Stepper Motor and Limit Switch
In this Arduino tutorial, We are going to learn how to use Arduino, limit switch, L298N driver and stepper motor. In detail, we are going to learn:
- How to stop stepper motor when a limit switch is touched
- How to change the direction of stepper motor when a limit switch is touched
- How to change the direction of stepper motor when two limit switches is touched
Hardware Required
Or you can buy the following sensor kits:
| 1 | × | DIYables Sensor Kit (30 sensors/displays) | |
| 1 | × | DIYables Sensor Kit (18 sensors/displays) |
Please note: These are Amazon affiliate links. If you buy the components through these links, We will get a commission at no extra cost to you. We appreciate it.
About Stepper Motor and Limit Switch
If you do not know about stepper motor and limit switch (pinout, how it works, how to program ...), learn about them in the following tutorials:
- Arduino - Limit Switch tutorial
- Arduino - Controls Stepper Motor tutorial
Wiring Diagram
This tutorial provides the Arduino codes for two cases: One stepper motor + one limit switch, One stepper motor + two limit switches.
- Wiring diagram between the stepper motor and a limit switch
This image is created using Fritzing. Click to enlarge image
- Wiring diagram between the stepper motor and two limit switches
This image is created using Fritzing. Click to enlarge image
※ NOTE THAT:
Depending on the stepper motor, the wiring connection between the stepper motor and L298N may be different. Please take a close look at this Arduino - Stepper Motor tutorial to see how to connect the stepper motor to the L298N motor driver.
Arduino Code - Stop Stepper Motor by a Limit Switch
There are several ways to make a stepper motor stop:
- Call stepper.stop() function: This way does NOT stop the stepper motor immediately but gradually
- Do NOT call stepper.run() function: This way stops the stepper motor immediately
The below code make a stepper motor spin infinitely and stop immediately when a limit switch is touched
/*
* Created by ArduinoGetStarted.com
*
* This example code is in the public domain
*
* Tutorial page: https://arduinogetstarted.com/tutorials/arduino-stepper-motor-and-limit-switch
*/
#include <ezButton.h>
#include <AccelStepper.h>
#define MAX_POSITION 0x7FFFFFFF // maximum of position we can set (long type)
ezButton limitSwitch(A0); // create ezButton object that attach to pin A0;
AccelStepper stepper(AccelStepper::FULL4WIRE, 7, 6, 5, 4);
bool isStopped = false;
void setup() {
Serial.begin(9600);
limitSwitch.setDebounceTime(50); // set debounce time to 50 milliseconds
stepper.setMaxSpeed(500.0); // set the maximum speed
stepper.setAcceleration(50.0); // set acceleration
stepper.setSpeed(100); // set initial speed
stepper.setCurrentPosition(0); // set position
stepper.moveTo(MAX_POSITION);
}
void loop() {
limitSwitch.loop(); // MUST call the loop() function first
if (limitSwitch.isPressed()) {
Serial.println(F("The limit switch: TOUCHED"));
isStopped = true;
}
if (isStopped == false) {
// without this part, the move will stop after reaching maximum position
if (stepper.distanceToGo() == 0) { // if motor moved to the maximum position
stepper.setCurrentPosition(0); // reset position to 0
stepper.moveTo(MAX_POSITION); // move the motor to maximum position again
}
stepper.run(); // MUST be called in loop() function
} else {
// without calling stepper.run() function, motor stops immediately
// NOTE: stepper.stop() function does NOT stops motor immediately
Serial.println(F("The stepper motor is STOPPED"));
}
}
Quick Steps
- Connect Arduino to PC via USB cable
- Open Arduino IDE, select the right board and port
- Navigate to the Libraries icon on the left bar of the Arduino IDE.
- Search “ezButton”, then find the button library by ArduinoGetStarted.com
- Click Install button to install ezButton library.
- Search “AccelStepper”, then find the AccelStepper library by Mike McCauley
- Click Install button to install AccelStepper library.
- Copy the above code and open with Arduino IDE
- Click Upload button on Arduino IDE to upload code to Arduino
- If the wiring is correct, you will see the motor rotates clockwise direction.
- Touch the limit switch
- You will see the motor is stopped immediately
- The result on Serial Monitor looks like below
COM6
The limit switch: TOUCHED
The stepper motor is STOPPED
The stepper motor is STOPPED
The stepper motor is STOPPED
The stepper motor is STOPPED
Autoscroll
Clear output
9600 baud
Newline
Code Explanation
Read the line-by-line explanation in comment lines of code!
Arduino Code - Change Direction of Stepper Motor by a Limit Switch
The below code make a stepper motor spin infinitely and change its direction when a limit switch is touched
/*
* Created by ArduinoGetStarted.com
*
* This example code is in the public domain
*
* Tutorial page: https://arduinogetstarted.com/tutorials/arduino-stepper-motor-and-limit-switch
*/
#include <ezButton.h>
#include <AccelStepper.h>
#define DIRECTION_CCW -1
#define DIRECTION_CW 1
#define MAX_POSITION 0x7FFFFFFF // maximum of position we can set (long type)
ezButton limitSwitch(A0); // create ezButton object that attach to pin A0;
AccelStepper stepper(AccelStepper::FULL4WIRE, 7, 6, 5, 4);
int direction = DIRECTION_CW;
long targetPos = 0;
void setup() {
Serial.begin(9600);
limitSwitch.setDebounceTime(50); // set debounce time to 50 milliseconds
stepper.setMaxSpeed(500.0); // set the maximum speed
stepper.setAcceleration(50.0); // set acceleration
stepper.setSpeed(100); // set initial speed
stepper.setCurrentPosition(0); // set position
targetPos = direction * MAX_POSITION;
stepper.moveTo(targetPos);
}
void loop() {
limitSwitch.loop(); // MUST call the loop() function first
if (limitSwitch.isPressed()) {
Serial.println(F("The limit switch: TOUCHED"));
direction *= -1; // change direction
Serial.print(F("The direction -> "));
if (direction == DIRECTION_CW)
Serial.println(F("CLOCKWISE"));
else
Serial.println(F("ANTI-CLOCKWISE"));
targetPos = direction * MAX_POSITION;
stepper.setCurrentPosition(0); // set position
stepper.moveTo(targetPos);
}
// without this part, the move will stop after reaching maximum position
if (stepper.distanceToGo() == 0) { // if motor moved to the maximum position
stepper.setCurrentPosition(0); // reset position to 0
stepper.moveTo(targetPos); // move the motor to maximum position again
}
stepper.run(); // MUST be called in loop() function
}
Quick Steps
- Copy the above code and open with Arduino IDE
- Click Upload button on Arduino IDE to upload code to Arduino
- If the wiring is correct, you will see the motor spins in the clockwise direction.
- Touch the limit switch
- You will see the stepper motor's direction is changed to the anti-clockwise
- Touch the limit switch again
- You will see the stepper motor's direction is changed to clockwise
- The result on Serial Monitor looks like below
COM6
The limit switch: TOUCHED
The direction -> ANTI-CLOCKWISE
The limit switch: TOUCHED
The direction -> CLOCKWISE
Autoscroll
Clear output
9600 baud
Newline
Arduino Code - Change Direction of Stepper Motor by two Limit Switches
The below code make a stepper motor spin infinitely and change its direction when one of two limit switches is touched
/*
* Created by ArduinoGetStarted.com
*
* This example code is in the public domain
*
* Tutorial page: https://arduinogetstarted.com/tutorials/arduino-stepper-motor-and-limit-switch
*/
#include <ezButton.h>
#include <AccelStepper.h>
#define DIRECTION_CCW -1
#define DIRECTION_CW 1
#define STATE_CHANGE_DIR 1
#define STATE_MOVE 2
#define STATE_MOVING 3
#define MAX_POSITION 0x7FFFFFFF // maximum of position we can set (long type)
ezButton limitSwitch_1(A0); // create ezButton object that attach to pin A0;
ezButton limitSwitch_2(A1); // create ezButton object that attach to pin A1;
AccelStepper stepper(AccelStepper::FULL4WIRE, 7, 6, 5, 4);
int stepperState = STATE_MOVE;
int direction = DIRECTION_CW;
long targetPos = 0;
void setup() {
Serial.begin(9600);
limitSwitch_1.setDebounceTime(50); // set debounce time to 50 milliseconds
limitSwitch_2.setDebounceTime(50); // set debounce time to 50 milliseconds
stepper.setMaxSpeed(500.0); // set the maximum speed
stepper.setAcceleration(50.0); // set acceleration
stepper.setSpeed(100); // set initial speed
stepper.setCurrentPosition(0); // set position
}
void loop() {
limitSwitch_1.loop(); // MUST call the loop() function first
limitSwitch_2.loop(); // MUST call the loop() function first
if (limitSwitch_1.isPressed()) {
stepperState = STATE_CHANGE_DIR;
Serial.println(F("The limit switch 1: TOUCHED"));
}
if (limitSwitch_2.isPressed()) {
stepperState = STATE_CHANGE_DIR;
Serial.println(F("The limit switch 2: TOUCHED"));
}
switch (stepperState) {
case STATE_CHANGE_DIR:
direction *= -1; // change direction
Serial.print(F("The direction -> "));
if (direction == DIRECTION_CW)
Serial.println(F("CLOCKWISE"));
else
Serial.println(F("ANTI-CLOCKWISE"));
stepperState = STATE_MOVE; // after changing direction, go to the next state to move the motor
break;
case STATE_MOVE:
targetPos = direction * MAX_POSITION;
stepper.setCurrentPosition(0); // set position
stepper.moveTo(targetPos);
stepperState = STATE_MOVING; // after moving, go to the next state to keep the motor moving infinity
break;
case STATE_MOVING: // without this state, the move will stop after reaching maximum position
if (stepper.distanceToGo() == 0) { // if motor moved to the maximum position
stepper.setCurrentPosition(0); // reset position to 0
stepper.moveTo(targetPos); // move the motor to maximum position again
}
break;
}
stepper.run(); // MUST be called in loop() function
}
Quick Steps
- Copy the above code and open with Arduino IDE
- Click Upload button on Arduino IDE to upload code to Arduino
- If the wiring is correct, you will see the motor spins in the clockwise direction.
- Touch the limit switch 1
- You will see the stepper motor's direction is changed to anti-clockwise
- Touch the limit switch 2
- You will see the stepper motor's direction is changed to clockwise
- The result on Serial Monitor looks like below
COM6
The limit switch 1: TOUCHED
The direction -> ANTI-CLOCKWISE
The limit switch 2: TOUCHED
The direction -> CLOCKWISE
Autoscroll
Clear output
9600 baud
Newline
Video Tutorial
We are considering to make the video tutorials. If you think the video tutorials are essential, please subscribe to our YouTube channel to give us motivation for making the videos.
