Clay Extruder

Description

The Clay Extruder is meant for controlling the flow of the pumped clay for extruding using a robot. The flow rate is controlled manually through a knob and it also includes an I/O digital input for cutting off the flow.

Hardware

This extruder uses an Auger Screw to push the clay with control out of the nozzle. For this reason an Arduino-controlled stepper motor was used to power up the screw.

1. Body

   

2. Motors and Electronics

   Parts

   • Arduino (Nano or Uno)
   • Stepper (Nema 17)
   • Stepper Driver
   • Optocoupler
   • Potentiometer
   • 12V Power Supply

   Circuit

   

Software

This project uses an Optocoupler to convert the 24V signals from a robot-arm into 5V logical level signal for the Arduino in order to introduce an I/O control for the extruder. Also a Potentiometer is used to control the flow speed manually.

1. code

   // Arduino NANO
   
   #include <SPI.h>
   
   volatile byte state = true;
   const byte interruptPin = 2;
   
   const int st_1 = 4;
   const int dr_1 = 5;
   const int en_1 = 8;
   const int sl_1 = A2;
   
   volatile int spd_2 = 500;
   int actual_spd_1 = 500;
   unsigned long t_1;
   
   void setup() {
     Serial.begin(9600);
     pinMode(st_1, OUTPUT);
     pinMode(en_1, OUTPUT);
     pinMode(dr_1, OUTPUT);
     pinMode(sl_1, OUTPUT);
   
     digitalWrite(dr_1, HIGH);
     digitalWrite(sl_1, LOW);
     digitalWrite(en_1, LOW);
   
     pinMode(interruptPin, INPUT);
   
     attachInterrupt(digitalPinToInterrupt(interruptPin),
                     motorsState, CHANGE);
   
     state = digitalRead(interruptPin);
     t_1 = micros();
   }
   
   void loop() {
     if (state) {
       if (micros() - t_1 > spd_1) {
         t_1 = micros();
         digitalWrite(st_1, HIGH);
       }
       else if (micros() - t_1 > 50) {
         digitalWrite(st_1, LOW);
       }    
     }
   }
   
   void motorsState() {
     state = !digitalRead(interruptPin);
   
     if (state) {
       digitalWrite(sl_1, LOW);
       digitalWrite(sl_2, LOW);
     } else {
       digitalWrite(sl_1, HIGH);
       digitalWrite(sl_2, HIGH);
     }
   
     Serial.print("Working?");
     Serial.print("\t");
     Serial.print(state);
     Serial.println();
   }

References:

• [Sample text](Sample text)
• [Sample text](Sample text)

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