Rocket 100% 3D printed

Print in solid material the engine stage and the nozzle.

The rocket is about 55cm long and 5cm in diameter

The nozzle can only withstand one flight because it has a conical shape that erodes during ignition. The nozzle is the white piece in the photos (I printed it in polycarbonate but it also works in ABS).

All the rest of the rocket is fully reusable.

You need to get an arduino nano as well as a tilt sensor that must be mounted on the plate printed with hot glue.

An electric igniter and a small amount of explosive that must be placed under the parachute to get the warhead out when the arduino detects the rocket rollover and triggers the igniter.

It takes 3 CR2450 battery mounted in the 3d printed case held closed by quick couplers. Then you have to insert the electrical wires on each side of the battery and power the arduino as well as a relay that will trigger the electric igniter.

You will also need m5 screws with countersunk heads and m5 metric inserts for mounting the stages

It also requires a steel or aluminum tube with an internal diameter of 30mm that will be used to assemble the 3 motors.

The mold is used to mold the propellant in the form of paste. Once cooled you can place the motors in the steel tube and mount the nozzle. I will not explain here how to make propellant but you will easily find on the internet how to make rocket candy or other amateur rocket propellant.

The last step is to make a launch pad with what you have (wood or metals) with a vertical guide at least 1.5 to 2 meters high.

You can start the engine with a standard ignition wick.

I also use an electric piezo to be sure that the arduino is started once the rocket is closed. Just flip it just 1 shot to hear a sound, it means that the parachute system is activated and functional. However, do not turn it over for more than 1 to 2 seconds because after 4 cumulative seconds, the parachute goes off. If you think you have turned it over too long restart the arduino.

Good flight

Below is the code for the arduino

int temps;  /*Pour etre sur qu'il ne s'agit pas de parasites dues aux vibrations */

void setup() {
 
  int etat=0;
  pinMode ( 2,OUTPUT);
  pinMode (3,INPUT);
pinMode (4,OUTPUT);

  Serial.begin(9600);
}

void loop() {
  int etat=digitalRead(3);
  Serial.println(temps);

  if(etat==0){
    tone(4,1200);
    delay(50);
    noTone(4);
    delay(50);
    tone(4,1200);
    noTone(4);
    delay (600);
    digitalWrite(2,LOW);
  }
  //si etat 0 sonne altrerné
  
  if((etat==1)&&(temps<5)){  /*test fonctionnement capteur inclinaison en retournant la fusée avant le lancement */
     temps=temps+1;
     tone (4,600);
    delay(800);
    noTone (4);
    delay(50);
    tone (4,2500);
    delay(200);
    noTone;
  }

  if((etat==1)&&(temps>=5)){/* 40 coups pour etre sur qu'il ne s'agit pas de parasites dues aux vibrations */
     temps=temps+1;
    tone(4,3500);
    delay(50);
  }
 
if(temps>=40){
  digitalWrite (2,HIGH);
  tone(4,2000);
 }
}