We attached the solenoid, air pressure system, recorder, arduino and relay to a foam board temporarily to hold each component in place, which allows us to begin testing codes on the solenoids to see if they can accurately plug the holes of the recorder. This board will be replaced in the next few weeks with a wooden frame. 

Frame Design

This is the preliminary design for the structural frame that will house the recorder and all of its electronic and mechanical components. This design is a four sided open box design, which simultaneously allows for all the structural components to be attached and so that a viewer could observe the inner workings of the instrument. In the design, in order to maintain access to all holes on the front and back of the instrument, the recorder will be turned sideways, so all push solenoids, the arduino and the relay board can be mounted on either side of the recorder on shelf-like platforms. 

Week 5

Weekly Objective - This week we are working on integrating the push solenoids into what we already have accomplished thus far. As we now have all the components and dimensions of each project element, we will also begin working on the frame design to more create a more stable and permanent mount for all electronics and the recorder itself. 

Circuit Design 
This is the revised version of the original circuit diagram of the pneumatic recorder. Small mistakes (unnecessary connections between each solenoid, missing connections to the common terminal in each relay, and errors with the input/output pins on the microcontroller) were fixed and the diagram now accurately represents what is actually going on electronically with our current working recorder prototype. 

Testing

During testing today, the device exhibited issues with back pressure. When the solenoid valve is closed during a rest in the music, the air hose pressurizes to its maximum behind the valve. When opened again, a sudden surge of air floods the recorder and produces a loud, undesirable noise. To combat this, wadding was stuffed inside of the 1’’ tubing to reduce the velocity and volume of the air reaching the mouthpiece of the recorder, much like a pop filter is placed in front of a microphone to slow down the air from sharp sounds like “P” and “B”.

Testing
In order to test the function of the air pressure and release system, Hot Cross Buns and Mary Had a Little Lamb were programmed in lab this week for timing in air release. Because the solenoid system is not yet complete the songs were tested by programming air release times and team members playing the notes. 

Hot Cross Buns

Mary Had a Little Lamb

Shout out to Kevin for carrying a 3 gallon, 70 pound air compressor around campus all day so that we could use it in Design Lab to test the recorder! 

Week 4

Weekly Objective - This week we are focusing on fine tuning the connection between the air compressor and the recorder, as well as testing different timing functions through programming. We are also working on the CAD design for the frame which holds the recorder, a structural support which will be constructed after determining how much space above and below the recorder the solenoids will need to rest. 

Music Selection
We also were introduced to the piece of music which our Lab Section will be playing. It is a medley of iconic soundtrack songs from the Harry Potter movies. Emily determined from the music that the recorder will be unable to play D# and C#, which are the only obvious restrictions of the music as the hardware can handle the speed of even the fastest sections.

Circuit Update
This week we started working with the relay board, the pneumatic solenoid and the arduino, which make up the majority of the air supply release system. Using an example blink function pre-programmed into the arduino we were able to test the opening and closing of the solenoid once properly wired to the relay board. The circuit is temporarily powered by a 12 volt, 4 amp power supply. Now that the circuit is set up, we are now able to determine the maximum speed that the pneumatic solenoid will be able to open and close, thus releasing air into the instrument. The speed of firing for the solenoid was pretty fast and the circuit therefore has an electrical capacity to play any possible note duration for any given song. What we have this week is a solid working proof of concept, and is a promising step forward in the circuit design because it shows that the original circuit diagram (that you should include in last weeks post) is feasible.

Arduino Programming
We tried figuring out a way to incorporate a BPM to milliseconds calculation for a variety of note durations so that we could change BPM at will and therefore simplify our delay usage, as is shown on the left. However, it seems that delays only take integer inputs and don't accept variables. This idea was scrapped, so now all delay duration calculations will be done by hand and input into each delay as an integer value. This section was removed and we started manual calculations  of how many milliseconds each note duration would equate to.

Week 3

Weekly Objective - This week we are starting to work on the air supply programming and ordering the push solenoids. As we collect the necessary electronic and mechanical parts for the recorder we will work on what we can with the materials we have in preparation for next week's upcoming deadline to produce sound with our instrument. Hopefully by next week we will have an arduino controlled air system, even if we have to play the notes by hand. Once we have the seven push solenoids, the goal will be to actually test specific notes.

Arduino Programming

This week we acquired our arduino from the ExCITe center during Design Lab and Emily began coding. To start off the arduino programming, we checked out some arduino citation, at https://www.arduino.cc/en/Reference/HomePage . First, we needed to figure out the pin assignments on the arduino. It was decided that pin 1 would be the pneumatic solenoid on the headpiece, and the remaining 7 pins would be assigned to 7 of the holes on the recorder. Once assigned we could start writing up the solenoid combination needed for each note. The end result for a given note looks something like this:

In this case, D4 (the first D above middle C) requires that all the solenoids be on, plugging the recorder holes. This is done by setting that pin to "low" which switches the relay into its open position and pushes the solenoid down.

We repeated this for all notes playable by our recorder, changing pin settings to "low" or "high" depending on which holes need closed or open, respectively.

Week 2

Weekly Objective - This week our Design Proposal  for the recorder will be handed in and reviewed. In class we will discuss the logistics of fabrication and meet with our project advisor to resolve any issues. Outside of lab we will continue to do mechanical and software related research as well as begin ordering parts we need and collecting those we have.

Circuit Design 

This is the preliminary circuit design of the project. It shows the rough plan for the connection of the pneumatic solenoid and the 7 push solenoids (top) to a relay board (middle) and an arduino microcontroller (bottom), as well as several outside power sources. This design still needs to be looked over and reviewed for mistakes and possible improvements. 

Timeline: This table shows a tentative timeline of activities for the completion of the pneumatic recorder. The recorder must be finished by week 8 in order to perform with the robotic symphony at the URBN Center Black Box Theater on May 27th, but will be presented individually Week 10. 

Budget: The estimated budget for this project is broken down into Mechanical Structure, Pneumatics, and Circuit Materials to account for the vastly different fabrication of each system. Most of the parts listed were found on Amazon or Home Depot's website. The items that were priced at $0 we either already own or have access to borrow.