Hi All,
I’m looking for some advice regarding some code for a servo-stepper project, I have found various bits of code online but… I’m struggling to finish the project as I’m lacking the understanding of how to implement the rest of the code to fulfill the project requirements.
The setup is a MEGA 2560, iHSV42 servo-stepper motor with integrated controller, 2 position digital switch to move the rig forwards and backwards, a potentiometer to adjust the speed, a limit switch to set the position and an LCD to output the speed and delay time.
When the rig powers up it moves towards the limit switch which should set the home position to 0 and then moves back near to the central position at a value of 5500.
I would like to keep the rig in the range of 0 to 12000 so when I press forward or backward the rig will stop before it goes past this point at either end?
I found this code from https://www.brainy-bits.com/homing-stepper-motor-at-startup/
void loop() {
// Enable movement of Stepper Motor using the Joystick
while (analogRead(x_pin) >= 0 && analogRead(x_pin) <= 100) {
if (steps > 0) { // To make sure the Stepper doesn’t go beyond the Home Position
digitalWrite(dir_pin, HIGH); // (HIGH = anti-clockwise / LOW = clockwise)
digitalWrite(step_pin, HIGH);
delay(1);
digitalWrite(step_pin, LOW);
delay(1);
steps–; // Decrease the number of steps taken
}
}
while (analogRead(x_pin) > 900 && analogRead(x_pin) <= 1024) {
if (steps < 650) { // Maximum steps the stepper can move away from the Home Position
digitalWrite(dir_pin, LOW);
digitalWrite(step_pin, HIGH);
delay(1);
digitalWrite(step_pin, LOW);
delay(1);
steps++; // Increase the number of steps taken
}
}
}
Lost on how how to implement this into the current code?
Also, I would like to output the position of the rig rather than the delay time to the LCD but if i try and display the value of x it just displays a static value of 5500 rather than the current position?
The code is as follows…
#include <Wire.h>
#include <LiquidCrystal_I2C.h>
#define potmeterPin A0 //DEFINE POTENTIOMETER PIN
#define home_switch 8 // Pin 8. connected to Home Switch (MicroSwitch)
LiquidCrystal_I2C lcd(0x27,16,2); // set the LCD address to 0x27 for a 16 chars and 2 line displ
String revision="1.3"; //==============ALTER THIS LINE FOR EACH CODE VERSION
const int dirPin = 2;
const int stepPin = 4;
const int enPin = 6;
const int switchOne = 10; //switch input pins
const int switchTwo = 11;
int p1buttonState = 0; // current state of the button
int lastp1buttonState = 0; // previous state of the button
int p2buttonState = 0; // current state of the button
int lastp2buttonState = 0; // previous state of the button
bool bPress = false;
bool isForward = false; //boolean definition as false
bool isBackward = false;
int x; // Used to set HOME position after Homing is completed
int sensorValue = digitalRead(home_switch);
//==========================================================================
void setup() {
Serial.begin(9600); //serial start
pinMode( switchOne, INPUT_PULLUP); //define inputs with pullups
pinMode( switchTwo, INPUT_PULLUP);
pinMode(stepPin,OUTPUT); // Sets the two pins as Outputs
pinMode(dirPin,OUTPUT);
pinMode(enPin,OUTPUT);
digitalWrite(enPin,LOW);
pinMode(home_switch, INPUT_PULLUP);
lcd.init(); // initialize the lcd
lcd.backlight(); // Turn on the blacklight and print a message.
//=====flash screen - Servo Tester and revision number
lcd.setCursor(0,0);
lcd.print("Servo Tester");
lcd.setCursor(0,1);
lcd.print("Version - ");
lcd.print(revision); //see variable to change on code upsuffix
delay(1500);
lcd.clear();
while (digitalRead(home_switch)) { // Do this until the switch is activated
digitalWrite(dirPin, HIGH); // (HIGH = anti-clockwise / LOW = clockwise)
digitalWrite(stepPin, HIGH);
delay(1); // Delay to slow down speed of Stepper
digitalWrite(stepPin, LOW);
delay(1);
// Serial.println("HOME");
}
while (!digitalRead(home_switch)) { // Do this until the switch is not activated
digitalWrite(dirPin, LOW);
digitalWrite(stepPin, HIGH);
delay(1); // More delay to slow even more while moving away from switch
digitalWrite(stepPin, LOW);
delay(1);
// Serial.println("AWAY");
}
x = 0; // Reset position variable to zero
}
//===============================================================
void loop() {
int p = analogRead(potmeterPin); //note pot value to varaible p
int delay_time = map(p,0,1023,100,1); //map pot from 100 to 0 on FSD
isForward = false; //boolean off
isBackward = false; //boolean off
p1buttonState = digitalRead(switchOne); //analogue read of switch inputs
p2buttonState = digitalRead(switchTwo);
if (p1ButtonPress()) {
digitalWrite(dirPin,HIGH); //write direction fwd
delay(5);
}
if (p2ButtonPress()) {
digitalWrite(dirPin,LOW); //change direction - backward
delay(5);
}
if( isForward || isBackward ){
Serial.println(millis());
for(x = 0; x < 5500; x++) { //step loop, 12000 is full length of rig
digitalWrite(stepPin,HIGH);
delayMicroseconds(delay_time);
digitalWrite(stepPin,LOW);
delayMicroseconds(delay_time);
}
Serial.println(millis());
}
lcd.setCursor(0,0); //set position of lcd start point line 1
lcd.print("Delay time - ");
lcd.print(delay_time);
lcd.setCursor(0,1);
lcd.print(((0.125*2)/delay_time)*10000);
lcd.print(" - mm/s");
Serial.println(delay_time);
}
//===============================================================
bool p1ButtonPress()
{
bool isPress = false;
if (p1buttonState != lastp1buttonState) { // compare the p1buttonState to its previous
if (p1buttonState == LOW) { // if the current state is HIGH then the button went from off to on:
bPress = true;
isPress = true;
Serial.println("Forward");
} else {
Serial.println("off"); // if the current state is LOW then the button went from on to off:
isForward = true;
}
delay(50); // Delay a little bit to avoid bouncing
}
lastp1buttonState = p1buttonState; // save the current state as the last state, for next time through the loop
return isPress;
}
//===============================================================
bool p2ButtonPress()
{
bool isPress = false;
if (p2buttonState != lastp2buttonState) { // compare the p1buttonState to its previous state
if (p2buttonState == LOW) { // if the state has changed, increment the counter
// if the current state is HIGH then the button went from off to on:
bPress = true;
isPress = true;
Serial.println("Backward");
} else {
Serial.println("off"); // if the current state is LOW then the button went from on to off:
isBackward = true;
}
delay(50); // Delay a little bit to avoid bouncing
}
lastp2buttonState = p2buttonState; // save the current state as the last state, for next time through the loop
return isPress;
}
//===========================================================
Can anyone help me please? :o
