How to build Robotic Arm using Arduino?

//Quartz Mini Robotic ARM - Testing code  

//Joystick 1 and 2 is connected to A0,A1, A2 and A3

//SERVO CONNECTIONS

//Neck sero - D10 - pos is saved at EEPROM 3

//Front and Back - D11 - pos is saved at EEPROM 2

//UP and Down - D9 - pos is saved at EEPROM 1

//Gripper - D6 - pos is saved at EEPROM 0

//created by: Aswinth Raj

//created for: quartzcomponents.com

#include <Servo.h>

#include <EEPROM.h>

//All the gripper positions will be saved and read from eeprom to resume same positon

int gripper_pos = EEPROM.read(0);

int updown_pos = EEPROM.read(1);

int frontback_pos = EEPROM.read(2);

int neck_pos = EEPROM.read(3);

// Create a servo object - one each for 4 servos

Servo Gripper_servo;

Servo UpDown_servo;

Servo FrontBack_servo;

Servo Neck_servo;

//Function the control the servo based on joystick position

void control_servo (Servo &current_servo, int current_pos, int EEPROM_addr)

{

    //positon should alwasy be between 0 to 180

    if (current_pos>=180)

    current_pos=175; //jitter at maximum limit

    if (current_pos<=0)

    current_pos=10; //jitter at minimum limit

    current_servo.write(current_pos); //update servo postion

    EEPROM.write(EEPROM_addr, current_pos); //save position in EEPROM

    Serial.print(EEPROM_addr); Serial.print(" = "); Serial.println(current_pos); //for debugging on serial monitor

}

void setup() {

  Serial.begin (9600);

  Gripper_servo.attach(6);

  Gripper_servo.write(gripper_pos);

  UpDown_servo.attach(9);

  UpDown_servo.write(gripper_pos);

  FrontBack_servo.attach(11);

  FrontBack_servo.write(gripper_pos);

  Neck_servo.attach(10);

  Neck_servo.write(gripper_pos);

}

void loop() {

  /*//USE FOR DEBUGGING

  Serial.println ("Gripper, UpDown, FrontBack, Neck");

  Serial.print(gripper_pos);Serial.print(",");

  Serial.print(updown_pos);Serial.print(",");

  Serial.print(frontback_pos);Serial.print(",");

  Serial.print(neck_pos);Serial.println(".");*/

  delay(50); //predefined  delay to make the servo move slower

//A0 to control Gripper Servo

  int Joy_value_X1 = analogRead (A0);

  if (Joy_value_X1 > 700){

    gripper_pos = gripper_pos + 1;

    control_servo (Gripper_servo, gripper_pos, 0);

  }

  if (Joy_value_X1 < 300){

    gripper_pos = gripper_pos - 1;

    control_servo (Gripper_servo, gripper_pos, 0);

  }

//A1 to control UpDown Servo

    int Joy_value_Y1 = analogRead (A1);

  if (Joy_value_Y1 > 700){

    updown_pos = updown_pos + 1;

    control_servo (UpDown_servo, updown_pos, 1);

  }

  if (Joy_value_Y1 < 300){

    updown_pos = updown_pos - 1;

    control_servo (UpDown_servo, updown_pos, 1);

  }

//A2 to control FrontBack Servo

      int Joy_value_X2 = analogRead (A2);

  if (Joy_value_X2 > 700){

    frontback_pos = frontback_pos + 1;

    control_servo (FrontBack_servo, frontback_pos, 2);

  }

  if (Joy_value_X2 < 300){

    frontback_pos = frontback_pos - 1;

    control_servo (FrontBack_servo, frontback_pos, 2);

  }

//A3 to control Neck Servo

        int Joy_value_Y2 = analogRead (A3);

  if (Joy_value_Y2 > 700){

    neck_pos = neck_pos + 1;

    control_servo (Neck_servo, neck_pos, 3);

  }

  if (Joy_value_Y2 < 300){

    neck_pos = neck_pos - 1;

    control_servo (Neck_servo, neck_pos, 3);

  }

}

Code Explanation

#include <Servo.h>

#include <EEPROM.h>

Here we have included servo and EEPROM library. All the position will be saved in EEPROM and will resume from the last position.

int gripper_pos = EEPROM.read(0);

int updown_pos = EEPROM.read(1);

int frontback_pos = EEPROM.read(2);

int neck_pos = EEPROM.read(3);

We have allotted the pin number to the respective joysticks to operate different arms of the robot.

Servo Gripper_servo;

Servo UpDown_servo;

Servo FrontBack_servo;

Servo Neck_servo;