Acoustic beamforming and beamsteering. Accenture Industry X LabDays 2023 Project.
Inspired by:
We are going to play sound at 8 speakers simultaneously. Due to wave effects the sound will be amplified at normal direction and diminished to the sides.
There are 2 variants of hardware and we don't know yet which one turns out better:
- MCU [SPI] -- External DAC -- Amplifier -- Speaker
- MCU [I2S] -- AudioDecoder [3.5mm jack] -- Amplifier -- Speaker
That leads us to a list of purchases:
| ECU | Why needed | Amount |
|---|---|---|
| STM32F4Discovery | Main MCU, STM32F407VG: 2 12-bit DAC, 2 I2S, SDIO | 1 |
| Adafruit MicroSD card reader | MicroSD card reader, that can be used by an MCU | 1 |
| INTENSO MSDHC4G | MicroSD card 4Gb | 1 |
| LM386 breakout board | Audio amplifier, from 4 Ohm, 0.325 | 8 |
| VIS K23-8 | Speaker, 8 Ohm, 0.3W, up to 20kHz | 8 |
| Adafruit I2S Stereo Decoder - UDA1334A | I2S to 3.5mm jack | 4 |
| BOOST-DAC8568 | External 8 channel DAC | 1 |
| DELOCK 65419 | 3.5mm plug with clamps | 4 |
Tools:
- Oscilloscope
- Multimeter
- Soldering iron
- Wires
- Breadboards
- Power module
- Formulas for sound processing
- Distance between speakers
- Criteria of efficiency for the multiple frequency case
Snippet-like project to use the hardware before the actual project
Links to learn embedded programming in general and STM32 in particular
- Step by step
- Play WAV-file
- And there's plenty information in Google both on embedded and STM32