Are We There Yet?

Progress: This is the SolidWorks sketch for the laser cut part. It will be the base in which the motor and the stand will be placed in. Today we as well drew up the final sketch for how the cannon will be attached and moved. The programming is still a work in progress. We have attempted to interface multiple codes with our board and Wii Nunchuck. None of them have worked. We will continue to search for codes that work and try to make progress on a possible Nunchuck - Arduino interaction.

Incorporating Arduino

Today we made drastic improvements on our project! Rather than requiring the two wires to be touched manually for a launch, we experimented with using a relay and a button in order to control the firing mechanism. The code for this follows this post. When this code and setup succeed, we proceeded to test many different pressure levels with Whoppers, ranging from 30 psi up to 80 psi. The video above is a high speed video shot on an iPhone 5s at 120 frames per second. A piece of paper towel was inserted to the barrel of the cannon prior to loading the Whopper to create a more air tight seal. The pressure loading on this shot was 80 psi. Although this is highly unrealistic for catching a Whopper in ones mouth, we were intrigued and decided to try high pressures such as this. It should also be noted that the paper towel is not necessary to launch the Whopper, this was merely to see what the effect of a more air tight seal would be. This was a huge step for us as using a push button to control the firing mechanism will be easily translatable to the Wii nun-chuck remote, our ultimate goal to control the firing of the candies.

The following code was used to create the launch using a push button and a relay:
"
int relay = 8;
int button = 2;

void setup(){
  pinMode(led,OUTPUT);
  pinMode(relay,OUTPUT);
  pinMode(button, INPUT_PULLUP);
 
  digitalWrite(relay, LOW);
}

void loop(){
  boolean buttonState = digitalRead(button);
 
  if(buttonState == 0){
    digitalWrite(relay, HIGH);
    delay(100);
    digitalWrite(relay, LOW);
   
  }
 
  if(buttonState == 1){
    digitalWrite(relay, LOW);
  }
}
"

First Launch!

Today we successfully executed our first trial launch! Upon inserting one Whopper, the air pressure was set to 50 psi. As you can see in the video the launch went very smoothly. Although the trajectory of the Whopper itself is difficult to see in the video you can see a small splash toward the right side of the video as the Whopper lands in the water. A few other trials were performed with varying pressure levels as well as one launch attempted with multiple pieces of candy. As the pressure tank still has an issue with a leak, these tests were mainly geared towards the functionality of the design. As soon as the leaking issue of the pressure tank is resolved we will be able to work more towards firing with precision. The tests today have proven that this design will ultimately work for our final goal of  catching candies in our mouths. After the design is finalized we would also like to experiment with candies other than Whoppers to see which may be easiest for participants to catch.

Progress

Design sketch

 Yesterday we finally managed to gather all the parts we needed to build the cannon. We were able to construct the cannon pretty successfully according to our design. However, we did encounter some difficulty with applying a seal around the valve being used to pump air into the pressure tank, which is causing our tank to lose pressure from a slow leak. Luckily, for the time being, this isn't stopping us from doing a few test launches. Our next step will be to construct the pan and tilt function on the cannon and then finally figure out how to program the whole system so that it can be aimed and fired with a wireless Wii nun-chuck controller.

Our cannon!

Shopping Excursion

Yesterday the group went on an excursion to Home Depot and the ever exciting Walmart. At Home Depot we encountered an employee named Dave, who throughout his adolescence tinkered with various schematics of potato guns and the sort. He was able to give us some helpful advice so to what sorts of parts that we need. One of the most important pieces of the design, a sprinkler head, was not able to be procured, which will delay the production of our project. We were able to find various pieces of PVC piping that will be used to create the air pressure tank as well as the barrel of the cannon. We made a quick stop at Walmart to acquire a few cartons of Whopper Candies. These seem more likely to create an effective launch rather than the previously thought of M&M's. Following this post is a picture of Andrew and Kevin thoroughly enjoying shopping in Home Depot expertly taken by the group photographer Jackie.

The Popinator!

Here is a much more complicated, slightly saltier version of what we hope to accomplish!

Change of Plans!

Due to the complexity of both building and programming a coil gun, we have decided to rethink our overall design, shifting our focus away from using electromagnetism to launch our projectiles to using air pressure. By creating a pressure tank and controlling the release of air using a sprinkler valve connected to an Arduino board, we hope to be able to successfully send our sweets flying.

Below is a rough sketch of what our pneumatic cannon will look like:

We hope to have all the supplies purchased and the cannon built by Tuesday, November 11 so we can start working on the remote controlled pan and tilt function on the cannon!