BrickPi Bookreader 2

Background

The original BrickPi Bookreader could already read Kindle pages aloud, but the community wanted something that could handle a real paper book. The challenge: there was no good, readily available page-turning mechanism to copy. Even Google failed to turn up something simple enough.

After exploring approaches including LEGO Pneumatics and professional book scanners, the team settled on a custom mechanism built almost entirely from LEGO bricks — parts they had in abundance.

The result, BrickPi Bookreader 2, can read any real paper book aloud and automatically turn each page. The voice is a little robotic, but it gets the job done.

How It Works

The page-turning mechanism uses two EV3 motors and a heavy LEGO wheel:

1. A weighted wheel rotates briefly, pushing the top page upward using friction.
2. A rotating arm swings 360° to flip the raised page over completely.
3. The Raspberry Pi Camera, mounted above the book, takes a photo of the new page.
4. Tesseract OCR converts the photo to text.
5. eSpeak speaks the text aloud through speakers connected to the Pi's audio jack.
6. The cycle repeats for the next page.

Parts Required

• BrickPi (any version)
• Raspberry Pi
• Raspberry Pi Camera Module
• 2 × LEGO EV3 Large Motors
• LEGO wheel (heavy, for page friction grip)
• LEGO beams and pins for the platform structure
• Small speaker (connected to the Pi's 3.5 mm audio jack)
• microSD card with Raspberry Pi OS Trixie for BrickPi3
• 12 V battery pack for BrickPi

Building the Bookreader

1. Set Up the Camera

Connect the Pi Camera module via the ribbon cable. The camera ships with its focus fixed at infinity, so you'll need to manually adjust the focus for close-up use (the camera will be about 25 cm above the book). Several community guides cover how to do this safely without damaging the lens.

Test the camera with:

raspistill -o image.jpg

Mount the camera at the desired height above the book. Take a test image and check that the full page is captured and the text is legible. Readjust height and focus until the text is sharp.

2. Set Up Text-to-Speech (eSpeak)

Check that audio output works first:

aplay /usr/share/sounds/alsa/*

Then install eSpeak:

sudo apt-get install espeak

Test it:

espeak "hello"

3. Install Tesseract OCR

sudo apt-get install tesseract-ocr

Take a photo of a printed page and test recognition:

tesseract image.jpg output

Open output.txt to review the result. If recognition is poor, try rotating the image 90° and re-running Tesseract.

4. Build the LEGO Platform

The structure that ended up being used looks somewhat like an AT-AT Walker from Star Wars — tall legs supporting a raised platform that holds both the BrickPi and the camera high enough above the book.

Key tips for the motor placement:

• The arm motor must only reach about 2.5 cm inside the book on each revolution so it gets a soft grip on the page without picking up multiple pages at once.
• The wheel motor must not be rigidly fixed — it should be able to pivot slightly at its mount point so it remains pressed down against the pages as they accumulate on one side.
• Motor port assignment: arm motor → Port A of BrickPi.

Use the test script in the GitHub repository to calibrate timing variables (speed_roller, speed_arm, t1, t2) until the page-turn reliably picks up exactly one page.

Putting It All Together

Once the camera, OCR, TTS engine, and LEGO platform are all working individually, download the main script from the BrickPi GitHub repository and run it:

git clone https://github.com/DexterInd/BrickPi_Python.git
cd BrickPi_Python
sudo python bookreader.py

Place an open book on the platform under the camera. The robot will photograph the page, read it aloud, then turn to the next page and repeat.