NYUSH2020S_9_ArduinoDrawingMachine.ino

/*
 * NYU Shanghai - Interactive Media Arts
 * 2020 Spring
 * This code was prepared for Interaction Lab
 * A simple drawing machine
 * 
 * It is based on "Controlling a servo" by Michal Rinott <http://people.interaction-ivrea.it/m.rinott>
 * the modifications by Scott Fitzgerald  http://www.arduino.cc/en/Tutorial/Knob
*/

#include <Servo.h>

Servo myservo;  // create servo object to control a servo

int anglePot = A0;  // analog pin used to connect the potentiometer 1
int motorPot = A1;  // analog pin used to connect the potentiometer 2
const int pinS = 9; //servo pin
const int pinM1 = 5; // motor pin1
const int pinM2 = 6; // motor pin2

void setup() {
  myservo.attach(pinS);  // attaches the servo on pin 9 to the servo object
  pinMode(pinM1, OUTPUT);
  pinMode(pinM2, OUTPUT);
}

void loop() {
  int valAngle = analogRead(anglePot);  // reads the desired servo position value of the potentiometer (value between 0 and 1023)
  valAngle = map(valAngle, 0, 1023, 30, 150);     // scale it to use it with the servo (value between 0 and 180)
  myservo.write(valAngle);                  // sets the servo position according to the scaled value
  delay(15); // waits for the servo to get there


  int valMotor = analogRead(motorPot);  // reads the desired motor speed value of the potentiometer (value between 0 and 1023)
  valMotor = map(valMotor, 0, 1023, -200, 200);
  if (valMotor > 0) {
    analogWrite(pinM1, valMotor);
    digitalWrite(pinM2, LOW);
  } else {
    digitalWrite(pinM1, LOW);
    analogWrite(pinM2, abs(valMotor)); //we use abs() to eliminate the negative sign of the value
  }
}