Chiran J. ( binary to decimal converter in PD )
Ankit G. ( Guitar Design using CATIA, PD sketch and weekly and final report)
Rich S. ( Hot glue, Wring, PD sketch, weekly and final report)
John H. ( PD Extended expert, The God of PD )
In the spring 2014 semester, service learning course led by John Harrison required Wichita State University students to collaborate with Maize High school students. The ultimate objective was to work with Maize students on projects that involve many different software’s including PD, which was the main programming software to be used. For our service learning project, we built a 12 button guitar Hero clone with Kenny, a talented maize high school student. We settled on a guitar hero clone for several reasons. The first one was to built something with the materials that would be cheap, quick and easy for anyone else to do it again, and more importantly because we knew we would have so much fun in doing this project. We built the guitar equipped two Arduino clones and two MaKey-MaKey clones, and a guitar design cut from XPS foam board ( Extruded Polystyrene ). Each Arduino was paired with a MaKey clone to receive input from 6 of the 12 buttons on the guitar neck. Both pairs were hot glued to the back of the guitar in a hallowed out cavity in the guitar body. The ground wires were connected together and connected to the aluminum contact pad SOUND HOLE. The rest of the connections (A0 – A5 ) on the MayKey clone were connected to the lower 6 or Upper 6 contact pads glued to the guitar neck. To make the connection a little more tidy we connected both Arduinos to a portable non-powered USB Hub.
On the software end, we used PD extended to interface with the Arduino clones through 2 com ports (USB PORTS). We used a main patch and two sub patches. In the main PD script ( MAIN PATCH: guitarhero ) we used two blocks that read data in from each Arduino port (button presses). The first sub patch (SUB-PACH ” pitchshifter“) wich takes the audio sample held in the ” soundBuffer ” and changes the pitch of the play back. The second ( SUB PACH ” note” ) utilizes the pitch shifter to make one wave file sound like 12 different notes. this is explained in better detail in the video (below).
After discussions among the group and drawing various rough sketches on paper, we came up with an initial design of a guitar. The team knew that the guitar was going to be made out of foam, using the CNC machine on the 3rd floor Wallace hall which requires sketches in pdf or some other specific formats. For this very reason, guitar design was created using CATIA by Ankit Gupta. The draft of CATIA was then modified with the help of INK-SCAPE to fit the format HPGL, which the CNC foam machine requires was made.
CUTTING THE FOAM:
The body neck and head of the guitar were traced from a cool looking guitar found by searching on google and using our own imagination. We included the PDF of the vector drawings obtained from CATIA drafts (below). These pdf files are the files which were to be used in INK_SCAPE to make it fit for the format required by CNC foam cutting machine
Vector drawings PDF files
and the final guitar
Here are a few pictures of us wiring the prototype and the finished wiring. Since the touch shields were sensitive to mechanical wiring connections we opted to solder as many connections as possible.
For the prototype we used the “polysynth” banana piano patch. We also made an attempt to use only one Arduino and a set of schmitt inverters for touch sensing and encode a 12 digit binary number ,one digit for each button, as a 4 digit decimal number then translate it back to binary in PD . However, in the end John worked up a more efficient functional block that replaced the polysynth. and we just used two Arduino clones and a USB hub. All of the patches need to be in the same directory for the program to work.
MAIN PATCH: guitarhero
SUB PATCH: ‘note“
SUB-PATCH ” pitchshifter“
All the audio files were downloaded from ( https://www.freesound.org/ )
guit1 is a bass,
guit2 is a single note from an acoustic guitar
and last but not the least guit3 is an OVER POWERED POWER CORD.
guit1 guit2 guit3
Through the opportunity of this project, the team members were able to learn many different skills from each other. Mr. Richard Staubin helped Ankit and Chiran with PD sketches and introduced them to the soft wares like INK-SCAPE. What started out as a mandatory course project, later turned out to be more than that, and the team enjoyed this whole process and again gained various educational insights to bring this project to completion. Kenny, the Maize high school student, was fast to learn PD and showed immense interest and hard work with team from WSU.
The result was a guitar, made out of foam programmed with Pure Data, which surprised many people and won their appreciation during the open house on 05/09/2014.
and finally here’s us playing with it LOL and explaining briefly what it is, with the actors Ankit and Richard.
WARNING: IT’S A LITTLE GOOFY !
In hind site, there are many features like pedal effects that would’ve made a great addition. But due to time constraints they couldn’t be implemented.
We also planned to decorate the body (bellow) but we didn’t have a high enough quality print.
The team would like to take this opportunity to thank Mr. Tom Mcguire (Senior design Lab assistant) for his contribution towards the success of building our guitar hero by helping us with foam cutting. The team would also like to thank Mr. John Harrison, who had been the real backbone of this project and course, to bring students together from WSU and Maize to work on project successfully. He also helped us with the PD sketches at the times when the team really needed and provided ideas and guidance to propel this project to completion.