3. Software

A project log for 3D Pottery Machine for kids' STEM education

Cornstarch mini pottery machine, built with an old printer and cd-player, and useful for kids' STEM education

Guillermo Perez GuillenGuillermo Perez Guillen 05/23/2022 at 01:330 Comments

I have used the Arduino IDE to experiment with this device, because it has many free tools that can be easily worked with. Next I show you the code in its first version.



#define POT A0  // Pot 10k
int raw_pot; // Store value of the pot
int duty;   // duty cycle - PWM

int STBY = 10;        // standby pin
// motor A
int PWMA = 3;        // velocity
int AIN1 = 9;                           
int AIN2 = 8;                           
// motor B
int PWMB = 5;        // velocity
int BIN1 = 11;                         
int BIN2 = 12;                         

void setup(){
  pinMode(STBY, OUTPUT);  
  pinMode(PWMA, OUTPUT);
  pinMode(AIN1, OUTPUT);
  pinMode(AIN2, OUTPUT);
  pinMode(PWMB, OUTPUT);
  pinMode(BIN1, OUTPUT);
  pinMode(BIN2, OUTPUT);

void loop(){
  raw_pot = analogRead(POT);
  duty = map(raw_pot, 0, 1023, 0, 255); // range vaalue from 0-255
  mover(1, duty, 1);                                // motor 1, velocity, forward
  mover(2, duty, 1);                                // motor 2, velocity, forward
  delay(50);                                        // 50 ms
void mover(int motor, int velocidad, int direccion){    //Let's define the move function,                                                                                            a acciona un motor, fijar su velocidad y el                                                                                            sentido de giro. Definimos:    //motor:                                                                                                    llamaremos 1 al motor A, y 2 al motor B
                                                        //velocity: from 0 to 255
                                                        //direction: 0 for clockwise, 1 for counter-clock wise
digitalWrite(STBY, HIGH);          //disable standby to move
 boolean inPin1 = LOW;             // we create the boolean variable (it can only be HIGH/LOW) inpin1
 boolean inPin2 = HIGH;             // and we assign the value LOW. To inPin2 we give the value                                                                HIGH
if(direccion == 1){
inPin1 = HIGH;
inPin2 = LOW;
if(motor == 1){
digitalWrite(AIN1, inPin1);
digitalWrite(AIN2, inPin2);
 analogWrite(PWMA, velocidad);
    digitalWrite(BIN1, inPin1);
    digitalWrite(BIN2, inPin2);
    analogWrite(PWMB, velocidad);
void stop(){                           // standby action 
  digitalWrite(STBY, LOW);

It is not complicated to analyze this code. We simply configure the microcontroller outputs to be able to use the TB6612FNG driver. The duty cycle of the PWM signal is regulated by means of a potentiometer placed on port A0.