How to Make a Small Cannon

Outside
My door
Unlocked
I'm lookin'
At this sound
That chime out of nowhere
Yeah, nowhere
Whoo
Wheels turnin'
Scratchin'
And burnin'
Yeah
I fought guns
Tanks
Cannon
Cannon
Yeah~
---Cannon wrote by Jack White

Several days ago, I have found my little sister was playing the computer game Tank of World and found the voice of cannon, accidently. The point is god view. A skilled player can use the god view and conquers all.

Although I don’t play Tank of World, I made a small cannon for my lovely player in reality. Okay, now we will make it together.

Main Components

DFRduino UNO R3
Gravity IO Expansion & Motor Driver Shield
DF15RSMG 360 Degree Motor (20kg)
DC Decelerate Motor
Push Button
Gravity: Analog Rotation Potentiometer Sensor V1 For Arduino
laser carved board

Assemble

1. All parts is shown as below.

2.Install the base 

Firstly, we need to assemble the support fame together.

Secondly, assemble the support fame lagging of barrel. 

Finally, assemble two support fames together to fix base.

The same installation goes for the support-fame in the other side.

Then we need to install module to fix the servo.

The whole base installation is accomplished.

3.Install Servo

Install servo rotatory arm

4.Install Motor

Connect the motor to cannon barrel

And install a plastic sprang part
P.s: The original wooden pick was broken by mistake so I printed a plastic pick by 3D printer.

5.Assemble Cannon Barrel

6.Overall Installation

Assemble gun barrel with the installed base.

Hardware Connection

Firstly, connect the motor wire into M1A and M1B.

Then plug servo to digital interface 13 of Gravity IO Expansion & Motor Driver Shield.

Then connect rotation sensor to A1 to control cannon firing angle with servo.

And connect the button to digital interface7 to shoot with motor.

After the assembling, let us turn it on to check the effect. 
We need to adjust the firing angle at first.
Then press the push button.

Code

#include <Servo.h>
Servo myservo;
//Motor A  
int PWMA = 3; //Speed control   
int AIN1 = 9; //Direction  
//Motor B  
int PWMB = 5; //Speed control  
int BIN1 = 11; //Direction   
 int key ; 
int item;
void setup(){ 
 myservo.attach(13);   
  int pos = 90;
  item = 0;
  Serial.begin(115200); 
  pinMode(PWMA, OUTPUT);  
  pinMode(AIN1, OUTPUT);  
  pinMode(PWMB, OUTPUT);  
  pinMode(BIN1, OUTPUT);  
  pinMode(7,INPUT);
  key=0; 
}  
void loop(){ 
   item = analogRead(A1);
   item = map(item, 0, 1023, 20, 55);
   Serial.println(item); 
   myservo.write(item);
   key=digitalRead(7);
   if(key==1){
    move(1, 200, 1); //motor 1, full speed, left  
    move(2, 200, 1); //motor 2, full speed, left  
    delay(1200); //go for 1.2 second    
  }  
 else{
   move(1, 0, 1); //motor 1, full speed, left  
   move(2, 0, 1);
   }
}
void move(int motor, int speed, int direction){  
 /*Move specific motor at speed and direction  
  *motor: 0 for B 1 for A  
  *speed: 0 is off, and 255 is full speed  
  *direction: 0 clockwise, 1 counter-clockwise  */ 
  boolean inPin1 = LOW;  
  boolean inPin2 = HIGH;  
  if(direction == 1){  
    inPin1 = HIGH;  
    inPin2 = LOW;  
   }  
  if(motor == 1){  
    digitalWrite(AIN1, inPin1);  
    analogWrite(PWMA, speed);  
   }
   else{  
    digitalWrite(BIN1, inPin1);  
    analogWrite(PWMB, speed);  
  }  
}  

3D Printing and Wooden Plate Design