P.Comp Final – Frequency Mapping + Assigning Scents

This week we documented our learnings from last week’s play-testing , researched air fresheners, worked out basic systems diagrams for both the device interactions and the user experience, hacked into the most suitable air freshener ((twice)) and explored pitch detection on Pure data.

One of the key components of this project is pitch detection. On detecting the certain assigned pitch/frequency, our device would spray the scent for the user to smell.

Scenario: The user sings a note. He/she sings this one note continuously for a certain length of time, say ‘x’ seconds. After ‘x’ seconds the user stops to take a breath. At this point he/she smells a scent.

1. How does the user recognize the degree of correctness? How can we differentiate the feedback for 50% correct and 70% correct ?
2. Should there be a scent denoting when the user went wrong?

We decided to program our device to keep detecting the pitch at very small but regular intervals of time. And at each interval (when the user is singing), based on if the user’s pitch falls between the ideal range or not, it sprays the positive or negative smell. This way, whenever the user stops singing and breathes in, he/she gets to review his performance by the intensity of the combination of the two smells).


To do this, we are using PURE DATA or MaxMSP. I tried a basic pitch detection patcher on PureData using the inbuilt microphone on my computer. The current version of Pd-Extended doesn’t work too well with the latest Mac models. So I will have to re-do this on Max.

PureData- Test 01

Next Steps:
1. Design a pitch detection system for the vocal scale A#
2. Determine ideal frequency ranges for each of the 7 notes
3. Learn how to map it on MaxMSP & Connect it to Arduino

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