Arduino Sherline Rotary Table controller

[sloucks]

So I decided that I wanted to be able to do repetitive moves on my Sherline cnc rotary table without using my computer and Mach3. Sherline makes a standalone controller but it's in the $400 range even on Ebay. Using an Arduino Nano, a 20x4 serial lcd, a 4x4 matrix keypad and a pololu stepper driver, I put together a simple stand alone rotary table controller. I'm using a 4amp 13.8v regulated DC power supply to power this project but I plan to use a laptop AC adapter when finished and put the controller in a 3d printed enclosure.

IMG_0007.jpgIMG_0008.jpg

I'm not a great Arduino programmer but here's the sketch:

/*
A program for controlling a single stepper motor driving a rotary table.
Uses a 4x4 matrix keypad for entry of degrees and direction to move the table.
Serial I2C display, Pololu stepper driver.
*/


#include <Wire.h> 
#include <LiquidCrystal_I2C.h>
#include <Keypad.h>

const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'.','0','#','D'}
};

byte rowPINS[ROWS] = {11,10,9,8};
byte colPINS[COLS] = {7,6,5,4};

Keypad kpd = Keypad(makeKeymap(keys),rowPINS,colPINS, ROWS, COLS);

LiquidCrystal_I2C lcd(0x27,20,4);  // set the LCD address to 0x20 for a 16 chars and 2 line display

 //setup vars
const int stp = 12;  //connect pin 12 to step
const int dir = 13;  // connect pin 13 to dir
const int StepsPerRotation = 400; //Set Steps per rotation of stepper
const int TableRatio = 72; //ratio of rotary table
const int Multiplier = (StepsPerRotation * TableRatio)/360;
const int stepdelay = 1;
 float Degrees = 0;                //Degrees from Serial input
 float ToMove = 0;                 //Steps to move
 int Direction;
 int repeat = 0;
 
 

void setup()
{
  lcd.init();                      // initialize the lcd 
  pinMode(stp, OUTPUT);
  pinMode(dir, OUTPUT); 
 
  // Print welcome message to the LCD.
  lcd.backlight();
  lcd.print("Rotary Table Control");
  lcd.setCursor(0,2);
  lcd.print("  CrankyTechGuy CNC");
  lcd.setCursor(0,3);
  lcd.print("   Copyright 2014");
  delay(2000);
  lcd.init();
}

void rotation(float tm, int d)
{   
  if(d == 0)
  {
    digitalWrite(dir, LOW);
  }
  else
  {
    digitalWrite(dir, HIGH);
  }
  
  for(int i = 0; i < tm; i++)  
   {    
    digitalWrite(stp, HIGH);   
    delay(stepdelay);               
    digitalWrite(stp, LOW);  
    delay(stepdelay);              
   }
}

float GetNumber()
{
   float num = 0.00;
   float decimal = 0.00;
   float decnum = 0.00;
   int counter = 0;
   char key = kpd.getKey();
   lcd.print("Rotary Table Control");
   lcd.setCursor(0,2);lcd.print("Enter degrees then");lcd.setCursor(0,3);lcd.print("press [#].");
   lcd.setCursor(8,1);
   bool decOffset = false;

   while(key != '#')
   {
      switch (key)
      {
         case NO_KEY:
            break;
            
         case '.':
           if(!decOffset)
           {
             decOffset = true;
           }
            lcd.print(key);
            break;   
           
         case '0': case '1': case '2': case '3': case '4':
         case '5': case '6': case '7': case '8': case '9':
         if(!decOffset)
         {
            num = num * 10 + (key - '0');
            lcd.print(key);
         }
         else if((decOffset) && (counter <= 1))
         {
            num = num * 10 + (key - '0');
            lcd.print(key);
            counter++;
         }
            break;
      }
      decnum = num / pow(10, counter);
      key = kpd.getKey();
   }
  return decnum;
}

int GetDirection()
{
  int dir = 0;
  lcd.setCursor(0,2);lcd.print("                    ");
  
  lcd.setCursor(0,3);
  lcd.print("    FWD[A] REV[B]");
  while(dir == 0)
  {
  char key = kpd.getKey();
  if(key == 'A')
  {
    dir = 1;
  }
  else if(key == 'B')
  {
    dir = -1;
  }
  }
     
lcd.clear();  
return dir;
}

void loop()
{
    if(repeat == 0)
    {
      Degrees = GetNumber();
      Direction = GetDirection();
    }
    
    Degrees = Degrees * Direction;

    if(Degrees < 0)
    {
      ToMove = (Degrees*Multiplier)*-1;
      lcd.setCursor(0,0);
      lcd.print("REV ");
      lcd.print(abs(Degrees),2);lcd.print((char)223);
      lcd.setCursor(6,1);
      lcd.print("Moving");
      rotation(ToMove,0);
      lcd.setCursor(6,1);
      lcd.print("      ");      
    }
    else
    {
      ToMove = Degrees*Multiplier;
      lcd.setCursor(0,0);
      lcd.print("FWD ");
      lcd.print(Degrees,2);lcd.print((char)223);
      lcd.setCursor(6,1);
      lcd.print("Moving"); 
      rotation(ToMove,1);
      lcd.setCursor(6,1);
      lcd.print("      "); 
    }
    lcd.setCursor(0,2);
    lcd.print("Repeat[A] Cancel[B]");
    char key = kpd.getKey();
    while(key != 'B')
    {
      key = kpd.getKey();
      if(key == 'A')
      {
        if(Degrees < 0)
        {
          ToMove = (Degrees*Multiplier)*-1;
          lcd.setCursor(6,1);
          lcd.print("Moving");
          rotation(ToMove,0);
          lcd.setCursor(6,1);
          lcd.print("      ");          
        }
        else
        {
          ToMove = Degrees*Multiplier;
          lcd.setCursor(6,1);
          lcd.print("Moving");
          rotation(ToMove,1);
          lcd.setCursor(6,1);
          lcd.print("      ");          
        }
      }
    }
    lcd.clear();
    
}

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[Khalid]

weldone. want to watch the video

[Tkamsker]

Question How high is the Holding force ? Looks nice

Gesendet von meinem SM-N9005 mit Tapatalk

[salzburg]

I know nothing about writing a sketch so I have to ask will the sketch still work if I change the Tableratio and the steps for a turn to 2oo.

[sloucks]

The stepper is a 270ozin stepper. With the worm drive system of the rotary table, holding force of the stepper isn't a huge factor.

[sloucks]

I know nothing about writing a sketch so I have to ask will the sketch still work if I change the Tableratio and the steps for a turn to 2oo.

The sketch calculates steps per degree of movement based on the steps per rotation of the stepper and table ratio. If you change these to match your stepper and table, it should work fine.

[sloucks]

Updated my Sketch. The controller will now allow you to choose between degrees or divisions.

/*
A program for controlling a single stepper motor driving a rotary table.
Uses a 4x4 matrix keypad for entry of degrees and direction or number of divisions to move the table.
Serial I2C display, Pololu stepper driver.
*/


#include <Wire.h> 
#include <LiquidCrystal_I2C.h>
#include <Keypad.h>

const byte ROWS = 4;
const byte COLS = 4;
char keys[ROWS][COLS] = {
  {'1','2','3','A'},
  {'4','5','6','B'},
  {'7','8','9','C'},
  {'.','0','#','D'}
};

byte rowPINS[ROWS] = {11,10,9,8};
byte colPINS[COLS] = {7,6,5,4};

Keypad kpd = Keypad(makeKeymap(keys),rowPINS,colPINS, ROWS, COLS);

LiquidCrystal_I2C lcd(0x27,20,4);  // set the LCD address to 0x20 for a 16 chars and 2 line display

 //setup vars
const int stp = 12;  //connect pin 12 to step
const int dir = 13;  // connect pin 13 to dir
const int StepsPerRotation = 400; //Set Steps per rotation of stepper
const int TableRatio = 72; //ratio of rotary table
const int Multiplier = (StepsPerRotation * TableRatio)/360;
const int stepdelay = 1;
float Degrees = 0;                //Degrees from Serial input
float ToMove = 0;                 //Steps to move
float Divisions;
float current = 0;
int Mode = 0; 
 

void setup()
{
  lcd.init();                      // initialize the lcd 
  pinMode(stp, OUTPUT);
  pinMode(dir, OUTPUT); 
 
  // Print welcome message to the LCD.
  lcd.backlight();
  lcd.print("Rotary Table Control");
  lcd.setCursor(0,2);
  lcd.print("  CrankyTechGuy CNC");
  lcd.setCursor(0,3);
  lcd.print("   Copyright 2014");
  delay(2000);
  lcd.init();
  Mode = GetMode();
}

void software_Reset() // Restarts program from beginning but does not reset the peripherals and registers
{
asm volatile ("  jmp 0");  
} 

void rotation(float tm, int d)
{   
  if(d == 0)
  {
    digitalWrite(dir, LOW);
  }
  else
  {
    digitalWrite(dir, HIGH);
  }
  
  for(int i = 0; i < tm; i++)  
   {    
    digitalWrite(stp, HIGH);   
    delay(stepdelay);               
    digitalWrite(stp, LOW);  
    delay(stepdelay);              
   }
}

float GetNumber()
{
   float num = 0.00;
   float decimal = 0.00;
   float decnum = 0.00;
   int counter = 0;
   char key = kpd.getKey();
   lcd.setCursor(0,0);lcd.print("Enter degrees then");lcd.setCursor(0,3);lcd.print("    press [#].");
   lcd.setCursor(0,30);lcd.print("Reset [D]");
   lcd.setCursor(8,2);
   bool decOffset = false;

   while(key != '#')
   {
      switch (key)
      {
         case NO_KEY:
            break;
            
         case '.':
           if(!decOffset)
           {
             decOffset = true;
           }
            lcd.print(key);
            break;   
           
         case '0': case '1': case '2': case '3': case '4':
         case '5': case '6': case '7': case '8': case '9':
           if(!decOffset)
           {
            num = num * 10 + (key - '0');
            lcd.print(key);
           }
           else if((decOffset) && (counter <= 1))
           {
            num = num * 10 + (key - '0');
            lcd.print(key);
            counter++;
           }
           break;

         case 'D':
           software_Reset();
         break;
      }

      decnum = num / pow(10, counter);
      key = kpd.getKey();
   }
  return decnum;
}

float GetDivisions()
{
   float num = 0.00;
   char key = kpd.getKey();
   lcd.clear();
   lcd.setCursor(0,0);lcd.print("Enter Divisions then");lcd.setCursor(0,1);lcd.print("     press [#].");
   lcd.setCursor(0,30);lcd.print("Reset [D]");
   lcd.setCursor(8,2);

   while(key != '#')
   {
      switch (key)
      {
         case NO_KEY:
            break;
            
         case '0': case '1': case '2': case '3': case '4':
         case '5': case '6': case '7': case '8': case '9':
            num = num * 10 + (key - '0');
            lcd.print(key);
            break;
        
        case 'D':
          software_Reset();
          break;
      }
      key = kpd.getKey();
     // num = 360/num;
   }
  return num;
}

int GetMode()
{
  int mode = 0;
  lcd.setCursor(0,1);lcd.print("Select Op Mode");
  
  lcd.setCursor(0,3);
  lcd.print("    DIV[A] DEG[B]");
  while(mode == 0)
  {
  char key = kpd.getKey();
  if(key == 'A')
  {
    mode = 1;
  }
  else if(key == 'B')
  {
    mode = 2;
  }
  }
     
lcd.clear();  
return mode;
}

void loop()
{
  if(Mode == 1)
  {
    Divisions = GetDivisions();
    Degrees = (360/Divisions);
  }
  if(Mode == 2)
  {
    Degrees = GetNumber();
  }
    lcd.clear();
    lcd.setCursor(0,3);
    lcd.print("FWD[A] REV[B] CAN[C]");
    char key = kpd.getKey();
    while(key != 'C')
    {
      lcd.setCursor(0,0);lcd.print("POS:");lcd.print(current);lcd.setCursor(0,1);lcd.print("DPM:");lcd.print(Degrees);
      key = kpd.getKey();
      if(key == 'A')
      {
       if(current >= 360)
       {
         current = (current + Degrees)-360;
       } else {
       current = current + Degrees;
       }
       ToMove = Degrees*Multiplier;
       lcd.setCursor(0,2);
       lcd.print("       Moving       ");
       rotation(ToMove,2);
       lcd.setCursor(0,2);lcd.print("                    ");
       lcd.setCursor(4,0);lcd.print("      ");
      }
      if(key == 'B')  
      {
       if(current <= 0)
       {
         current = 360+(current - Degrees);
       } else {
       current = current - Degrees;
       }
       ToMove = Degrees*Multiplier;
       lcd.setCursor(0,2);
       lcd.print("       Moving       ");
       rotation(ToMove,0);
       lcd.setCursor(0,2);lcd.print("                    ");
       lcd.setCursor(4,0);lcd.print("      ");
       }
     }
     lcd.clear();    
}

[forhire]

Pretty slick. Does the Sherline rotary table have a home switch?

[sloucks]

No. It would be easy to add one, though I don't have many digital inputs left on the Arduino.

[BigMc]

Hello sloucks,

Is it possible to show more of your wiring diagram? kinda hard for noob like me to trace it all back. I seem to encounter an error on the LiquidCrystal_I2C, do you know where you get the library from? The current one don't seem to be in agreement with the sketch?
I received this message when verifying:
C:\Users\Documents\Arduino\libraries\LiquidCrystal_I2C/LiquidCrystal_I2C.h:80: error: conflicting return type specified for 'virtual void LiquidCrystal_I2C::write(uint8_t)'
C:\Program Files (x86)\Arduino\hardware\arduino\cores\arduino/Print.h:48: error: overriding 'virtual size_t Print::write(uint8_t)'

Hopes someone can shine a light?

Many thanks

[sloucks]

Here is the schematic for my stepper controller. I do not know what the error you are getting is. I got the LiquidCrystal_I2C library from HERE .

RotaryStepper Schematic.jpg

[edbart]

Hi, the script does not compile without error.