With increasing awareness of mental health problems, speech impediments, and disabilities like Autism Spectrum Disorder (ASD), many may get tested. Still, they may not have the financial means to afford assistive technology.

Augmentative and Alternative Communication (AAC) devices, such as speech-generating devices, can be out of reach for many. Although they want to give such devices a try, the initial investment can be a significant obstacle.

A cost-effective solution is required to fill this gap, and I have designed a device that aims to address this challenge.

The prototype uses:

• RP2040 (Waveshare RP2040 Zero used) - 300 INR
• HW-125 SD card adapter - 40 INR
• 4GB Micro-SD card - 120 INR
• 4x AA battery holder and batteries - 70 INR
• 5V Buck converter - 83 INR
• PAM8403 amplifier board + speaker - 20 INR (speaker from junk)
• 4x 36 mm tactile switches - 600 INR
• Simple 3D printed enclosure - Free

Total cost = 1233 INR (or 14.44 USD, where 1 INR = 0.012 USD).

The device's features:

• The code is written in CircuitPython.
• .WAV files are supported.
• Modules/breakout boards are used when possible to simplify wiring and improve maintainability.
• 4 buttons allow for 4 phrases. The code is scalable to add more buttons.

Program working:

• Each button pin is paired with an ID. A button plays the corresponding .wav file from the SD card. The button with ID X will play 'audiox.wav' from the SD card. For example, the button with ID 1 will play 'audio1.wav'.
• Users must record .wav audio files from any microphone app and store them on the SD card with the appropriate name.
• The speaker will play the audio file when the corresponding button is pressed. Another button press won't interrupt the currently playing audio.

Required features to make the device better:

• Better components to improve efficiency and repairability. A PCB to plug everything into will help reduce wiring failures.
• Improved button design to support adding/removing images on the button. Graphics will help the user know what a button is for
• Test for battery life. 4xAA is insufficient for prolonged usage. Either additional batteries must be added, or rechargeable options should be explored.
• A recording device, to allow users to record new phrases without a laptop/computer.
• An enclosure with more structural integrity to withstand falls.