Tianrui Zhang - Sun 19 April 2020, 11:28 pm

We currently think of three ways to implement our design

1. Each part is independent

We have four parts: test tube, dropper, flask and trash can. Each part is powered separately, making a separate circuit board.

Among them, the test tube functions as a voice recorder. If the parts are separated, the songs need to be transmitted wirelessly. The way we thought of is to use Bluetooth or WiFi to transmit songs, but there is no idea how to achieve it.

2. All the parts share one development board

Create a large development board with a recording function, playback function, and audio processing function. We will install speakers, microphones, and memory cards on this development board. Then connect the test tube, flask, and dropper to this development board with wires.

3. Using a computer

The computer has a speaker, microphone, storage space and audio processing software. Test tubes, flasks, and droppers are only installed with interactive functions, and the functions related to music are all performed by the computer.

this week our group made a further understanding of the technical aspects of the idea and found that the Arduino circuit board is only 32k, and our project involves sound storage, recording, mixing, etc. Arduino cannot store and run so many functions, If we don't use the recording, playback and storage functions on your computer, then we need to make special hardware (e.g own mini-board, PCB, breadboard, etc.) and purchase suitable speakers, SD card, analog audio amplifier and other tools to complete the follow-up Prototype. Due to the particularity of the period, we may not be able to purchase and produce it within the specified time. At present, the alternative method that we have in mind is to use the sensors in Arduino to complete the interactive function, and use the recording playback and mixing functions on the computer to complete the audio processing.

working principle:

  1. Recording: the analog signal of the microphone is converted into digital to an analog signal, and the digital signal is stored in code
  2. Play: The stored audio file is decoded, after digital-to-analog conversion, it becomes an analog signal and is released from the speaker
  3. The mixing program can be found in the embedded mixing library, FFmpeg is a clue
  4. Write the whole program to control the MCU

This forum is talking about the recording function, we are facing a similar problem https://www.avrfreaks.net/forum/sound-recorder-using-microcontroller



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