Published September 4, 2024

eBook Page Turner

Introducing the eBook Page Turner: Turn pages effortlessly with simple gestures, perfect for those with limited hand or arm mobility.

IntermediateFull instructions provided127

Honorable Mention Mobility Impairments

Build2gether 2.0 — Inclusive Innovation Challenge

Things used in this project

Hardware components

Nordic Semiconductor nRF52 Development Kit

nRF52840-DK

PCBWay Custom PCB

nRF52840-DK Shield

SG90 Micro-servo motor

MG90S (Need to work at 3V)

Connector Header Through Hole, Right Angle 0.100" (2.54mm)

2x 3 Position for Servos, 3x 2 Position for Battery Conn, 2x 5 Position for Gesture Sensor (Replaceable for JST 5 Position, 2.54mm R.A.)

Female/Female Jumper Wires

5x Gesture Sensor Connection 2x Battery Conn to nRF52840-DK

Screw M3

4x M3x5mm Screw for nRF52840-DK 3x M3x30mm Screw for PCB Cover 4x M3x10mm Screw (x2 Gesture Sensor, X2 for Stand)

Nut M3

Hex Nut M3 x2 For the Gesture Sensor, x2 For the Stand

Switch SS12D00

SP2T SS12D00

Gesture Sensor APDS-9960

M2 Screw

4x M2x8mm for Servo attachment to the Case (2 per Servo) 2x M2x10mm for Servo attachment to the Arm (1 per Servo)

Software apps and online services

Arduino IDE

Nordic Semiconductor nRF Connect SDK

Siemens SolidWorks

Only use if you need to modify the Kindle enclosure to fit other models

BambuStudio

Hand tools and fabrication machines

Soldering iron (generic)

Solder Wire, Lead Free

3D Printer (generic)

Story

Introduction

eReaders have revolutionized the way we consume books, offering a convenient alternative to traditional books. With their lightweight design and vast storage capacity, eReaders allow users to carry thousands of books on a single device, making reading more accessible and portable than ever before.

However, for individuals with mobility impairments, eReaders can present certain challenges. These devices typically require precise finger movements to physically tap or swipe specific areas of the screen to turn pages. This can be difficult for those with limited mobility in their arms or hands, making it harder for them to fully enjoy the benefits of digital reading.

eBook Taping Position

Solution:

To address the obstacles that people with mobility impairments face when using eReaders, one potential solution is to equip eReaders with motion detection technology. This would allow users to navigate through the device without needing to tap or swipe the screen precisely. For example, simple hand or arm movements to the right or left could be detected by the device to turn pages forward or backward in the eReader.

While some devices already offer the ability to turn pages using a remote control, these typically work only with eBooks that have capacitive screens (like those found on smartphones or tablets) and are not compatible with older models or those without a touchscreen.

Example of eBook page Turner only compatible with Kindle PaperWhite 2,4,5

How it Works:

Video of the device

The eReader is attached to the electronics using a stand, which allows it to be easily detached for tasks such as charging, adding books, or adjusting settings like font size.

eBook easy to detach stand

Once the eReader is placed on the 3D-printed stand and the back switch is turned on (to use the Li-Po battery) or a cable is connected to the USB port, the gesture sensor will detect movements to the right or left, activating the servos to turn the page forward or backward.

Back Switch for Li-Po battery use

This device is designed for the Kindle 8th generation, which features an infrared touchscreen. which makes current market devices incompatible with thisebook. If the user has a different model of eReader, the CAD file for the stand can be easily modified to fit the new size.

Additionally, the length of the servo arms must be adjusted to reach the correct position on the screen of the new device.

Types of Touchscreens

Note: If the user has a device with a capacitive screen, it is necessary to add a wire connected to GND to both servo arms.

Hardware:

The project is based on two main components:

Infrared Gesture Sensor APDS-9960.
Two MG90S Servomotors.

APDS-9960: The gesture detection sensor utilizes four directional photodiodes to sense reflected IR energy (sourced by the integrated LED) to convert physical motion information (i.e. velocity, direction and distance) to a digital information,

Then the gesture engine accommodates a wide range of mobile device gesturing requirements: simple UP-DOWN-RIGHT-LEFT gestures or more complex gestures can be accurately sensed.

Leftward motion

Example: LEFT Motion: When a hand is swiped from right to left across the four photodiodes and the IR LED, the hand will first pass over the R (right) photodiode, then U (up) and D (down), and finally L (left).

The sensing algorithm recognizes the increase in signal at the R photodiode and records a timestamp for this rise. It then detects similar signal increases at the U and D photodiodes, followed by L, with each signal rise recorded at progressively later timestamps.

The algorithm also detects when each photodiode returns to its normal, no-detection state, recording timestamps for these events as well. First, L returns to normal, followed by U and D, and finally R.

At the end of the process, the result is four 8-bit gesture values corresponding to the accumulated signal strength at each photodiode.

8-bit gesture Leftward Motion

MG90S Servomotor: Once the gesture (LEFT or RIGHT) is detected, the corresponding servo motor is activated (R Servo for a RIGHT gesture and L Servo for a LEFT gesture). A servo motor is a DC motor that controls rotation by adjusting the length of a square wave pulse sent to its control circuit. The length of each pulse is defined by Pulse Width Modulation (PWM).

The pulse train is characterized by its duty cycle, which is the ratio of the pulse duration (time the signal is in the "on" state) to the total period of the signal. For example, a classic square wave has a 50% duty cycle, meaning the "on" time (pulse) occupies half of the wave's period, with the other half being "off."

By varying the duty cycle of the PWM signal, the angle of the servo motor's rotation can be controlled. Starting with a duty cycle of 1%, which corresponds to a 0° angle, increasing the duty cycle increases the rotation angle. At a 50% duty cycle, the motor's pin positions itself at 90°. A duty cycle of 99% results in a rotation of 180°.

Duty Cycle vs Angle of Rotation

Build Instructions

1. 3DPrinting and Soldering:

Print the 3D parts with a layer height of 0.3 mm and 15% infill. This combination should provide a sturdy build and ensure a good fit between the pieces.
Solder a 5x 2.54mm pin header to the Gesture Sensor APDS-9960 (the "VL" port is unused).
Solder the components to the custom PCB, including the switch and pin headers.
Solder a 2x 2.54mm pin header to the nRF52840-DK for connecting the battery cables.

1 / 3 • Gesture Sensor APDS-9960 Solder Pins

2. Attach the Components to the Case:

Glue the Case Pieces: Glue together the two parts of the case (Back.stl and Front.stl). The case is divided into these two pieces to eliminate the need for supports during printing.
Attach the Servos and Gesture Sensor: Secure the servos to the case using M2x8 mm screws (2 per servo, 4 in total) and attach the gesture sensor with two M3x10 mm screws and two M3 nuts.
Mount the nRF52840-DK: Position the nRF52840-DK with the nRF Power Source in the VDD position and secure it to the case with four M3x5 mm screws. Install the nRF52840-DK before attaching the PCB shield on top.
Attach the PCB Shield: Mount the PCB shield onto the nRF52840-DK board and connect the servos and the gesture sensor to the PCB shield, making sure not to connect the "VL" pin from the gesture sensor.

1 / 4 • Attach Servos + Gesture Sensor to the Case

3. Connect the battery:

Attach the Battery: Connect the Li-Po battery (maximum 5V) to the bottom port, ensuring that the positive terminal is connected to the "+" input.
Install the Switch Cover: Place the 3D-printed switch cover onto the power switch.
Secure the Casing: Cover the battery and PCB with the protective casing using three M3x30 mm screws.

1 / 3 • Battery Attachment

4. Stand Build: The stand is assembled using two parts: a base and an angled piece (Stand 1/2 and Stand 2/2). These parts are combined to position the eBook at a comfortable angle for use. Secure the two pieces together with two M3x10 mm screws and two M3 nuts.

1 / 3 • Stand: Assembled

5.Arm Attachment: Connect the 3D Printed TPU arms to the servos, use a M2x10mm screw, make sure to place them at 90 degrees with a slight inward tilt.

1 / 2 • Arm Servo 2

6. Finish Build: Place the eBook in the stand. By turning on the back switch, the device will respond to RIGHT/LEFT gestures and turn the pages forward or backward.

FINISH

Programming the Board

Usually, you would need to use the nRF Studio Extension for VSCode, which can be complicated for beginners or too complex if you have to use external libraries. However, there is a way to program it using the Arduino IDE:

1. Install the latest version of nRF Connect and Arduino IDE.

2. Install the Adafruit nRF52 Board Package Using the Boards Manager.

3. Go to Arduino15\packages\adafruit\hardware\nrf52\variants\feather_nrf52832.

4. Change the variant.cpp/.h for custom the ones (see the attachments).

Uploading the Code

Follow these steps to upload your code to the board:

1. Erase the memory of the board using the nRF Connect -> Programmer.

2. Burn the bootloader to the board (close the Serial Port during this step and don't disconnect your board) using the Adafruit Feather nRF52832Board.

3. Upload your code to the board and when finish the program will start running.

Note:If the process fails, try repeating the steps, ensuring the memory is fully erased, and switching between available ports (e.g., COM3 and COM4) if necessary.

1 / 2 • Step 1

Future Development:

This project has introduced the first prototype of a device designed to assist users with arm or hand impairments in turning eBook pages effortlessly. Future upgrades to the eBook Page Turner may include:

1.Charging Port for Li-Po Battery: Currently, the battery must be charged externally. Future iterations could incorporate a USB-C port for recharging.

2.More Complex Functions: The current device only supports basic functions such as turning pages forward or backward. Future versions could explore adding more complex functions, like adjusting font size or switching books. However, this would require accommodating the various swipe or touch combinations needed for different eBook systems.

3.Alternative Detection Methods: Expanding input options through face gesture recognition or voice commands could provide additional ways for users to interact with the device, enhancing its functionality for turning pages.

Schematics

Code

#include <Wire.h>
#include <SparkFun_APDS9960.h>
#include <Servo.h>

// Pins
#define APDS9960_INT    3 // Needs to be an interrupt pin


// Global Variables
SparkFun_APDS9960 apds = SparkFun_APDS9960();
int isr_flag = 0;
Servo rightServo;  
Servo leftServo;   

void setup() {
  // Set interrupt pin as input
  pinMode(APDS9960_INT, INPUT);

  // Initialize Serial port
  Serial.begin(9600);
  Serial.println();
  Serial.println(F("--------------------------------"));
  Serial.println(F("SparkFun APDS-9960 - GestureTest"));
  Serial.println(F("--------------------------------"));

  // Initialize interrupt service routine
  attachInterrupt(digitalPinToInterrupt(APDS9960_INT), interruptRoutine, FALLING);

  // Initialize APDS-9960 (configure I2C and initial values)
  if ( apds.init() ) {
    Serial.println(F("APDS-9960 initialization complete"));
  } else {
    Serial.println(F("Something went wrong during APDS-9960 init!"));
  }

  // Start running the APDS-9960 gesture sensor engine
  if ( apds.enableGestureSensor(true) ) {
    Serial.println(F("Gesture sensor is now running"));
  } else {
    Serial.println(F("Something went wrong during gesture sensor init!"));
  }

  // Attach servos to their respective pins
  rightServo.attach(33); 
  leftServo.attach(34);  
}

void loop() {
  if( isr_flag == 1 ) {
    detachInterrupt(digitalPinToInterrupt(APDS9960_INT));
    handleGesture();
    isr_flag = 0;
    attachInterrupt(digitalPinToInterrupt(APDS9960_INT), interruptRoutine, FALLING);
  }
}

void interruptRoutine() {
  isr_flag = 1;
}

void handleGesture() {
  if ( apds.isGestureAvailable() ) {
    switch ( apds.readGesture() ) {
      case DIR_UP:
        Serial.println("UP");
        break;
      case DIR_DOWN:
        Serial.println("DOWN");
        break;
      case DIR_LEFT:
        Serial.println("LEFT");
        leftServo.write(0);
        delay(500);     
        leftServo.write(90);
        break;
      case DIR_RIGHT:
        Serial.println("RIGHT");
        rightServo.write(180);
        delay(500);
        rightServo.write(90);
        break;
      case DIR_NEAR:
        Serial.println("NEAR");
        break;
      case DIR_FAR:
        Serial.println("FAR");
        break;
      default:
        Serial.println("NONE");
    }
  }
}

/*
  Copyright (c) 2014-2015 Arduino LLC.  All right reserved.
  Copyright (c) 2016 Sandeep Mistry All right reserved.
  Copyright (c) 2018, Adafruit Industries (adafruit.com)

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.

  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU Lesser General Public License for more details.

  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

#include "variant.h"

#include "wiring_constants.h"
#include "wiring_digital.h"
#include "nrf.h"

const uint32_t g_ADigitalPinMap[] =
{
  // P0
  0 , 1 , 2 , 3 , 4 , 5 , 6 , 7 ,
  8 , 9 , 10, 11, 12, 13, 14, 15,
  16, 17, 18, 19, 20, 21, 22, 23,
  24, 25, 26, 27, 28, 29, 30, 31,

  // P1
  32, 33, 34, 35, 36, 37, 38, 39,
  40, 41, 42, 43, 44, 45, 46, 47
};


void initVariant()
{
  // init all 4 onboard LEDs
  pinMode(PIN_LED1, OUTPUT);
  ledOff(PIN_LED1);

  pinMode(PIN_LED2, OUTPUT);
  ledOff(PIN_LED2);

  pinMode(PIN_LED3, OUTPUT);
  ledOff(PIN_LED3);

  pinMode(PIN_LED4, OUTPUT);
  ledOff(PIN_LED4);
}

 /*
  Copyright (c) 2014-2015 Arduino LLC.  All right reserved.
  Copyright (c) 2016 Sandeep Mistry All right reserved.
  Copyright (c) 2018, Adafruit Industries (adafruit.com)

  This library is free software; you can redistribute it and/or
  modify it under the terms of the GNU Lesser General Public
  License as published by the Free Software Foundation; either
  version 2.1 of the License, or (at your option) any later version.
  This library is distributed in the hope that it will be useful,
  but WITHOUT ANY WARRANTY; without even the implied warranty of
  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
  See the GNU Lesser General Public License for more details.
  You should have received a copy of the GNU Lesser General Public
  License along with this library; if not, write to the Free Software
  Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/

#ifndef _VARIANT_FEATHER52832_
#define _VARIANT_FEATHER52832_

/** Master clock frequency */
#define VARIANT_MCK       (64000000ul)

#define USE_LFXO      // Board uses 32khz crystal for LF
// define USE_LFRC    // Board uses RC for LF

/*----------------------------------------------------------------------------
 *        Headers
 *----------------------------------------------------------------------------*/

#include "WVariant.h"

#ifdef __cplusplus
extern "C"
{
#endif // __cplusplus

// Number of pins defined in PinDescription array
#define PINS_COUNT           (48u)
#define NUM_DIGITAL_PINS     (48u)
#define NUM_ANALOG_INPUTS    (6u)
#define NUM_ANALOG_OUTPUTS   (0u)

// LEDs
#define PIN_LED1             (13)
#define PIN_LED2             (14)
#define PIN_LED3             (15)
#define PIN_LED4             (16)

#define LED_BUILTIN          PIN_LED1
#define LED_CONN             PIN_LED2

#define LED_RED              PIN_LED1
#define LED_BLUE             PIN_LED2

#define LED_STATE_ON         0         // State when LED is litted


/*
 * Buttons
 */
#define PIN_BUTTON1          11
#define PIN_BUTTON2          12
#define PIN_BUTTON3          24
#define PIN_BUTTON4          25


/*
 * Analog pins
 */
#define PIN_A0               (3)
#define PIN_A1               (4)
#define PIN_A2               (28)
#define PIN_A3               (29)
#define PIN_A4               (30)
#define PIN_A5               (31)
#define PIN_A6               (0xff)
#define PIN_A7               (0xff)

static const uint8_t A0  = PIN_A0 ;
static const uint8_t A1  = PIN_A1 ;
static const uint8_t A2  = PIN_A2 ;
static const uint8_t A3  = PIN_A3 ;
static const uint8_t A4  = PIN_A4 ;
static const uint8_t A5  = PIN_A5 ;
static const uint8_t A6  = PIN_A6 ;
static const uint8_t A7  = PIN_A7 ;
#define ADC_RESOLUTION    14

// Other pins
#define PIN_AREF           (2)
#define PIN_NFC1           (9)
#define PIN_NFC2           (10)

static const uint8_t AREF = PIN_AREF;

/*
 * Serial interfaces
 */
#define PIN_SERIAL_RX       (8)
#define PIN_SERIAL_TX       (6)

/*
 * SPI Interfaces
 */
#define SPI_INTERFACES_COUNT 1

#define PIN_SPI_MISO         (46)
#define PIN_SPI_MOSI         (45)
#define PIN_SPI_SCK          (47)

static const uint8_t SS   = 44 ;
static const uint8_t MOSI = PIN_SPI_MOSI ;
static const uint8_t MISO = PIN_SPI_MISO ;
static const uint8_t SCK  = PIN_SPI_SCK ;

/*
 * Wire Interfaces
 */
#define WIRE_INTERFACES_COUNT 1

#define PIN_WIRE_SDA         (26u)
#define PIN_WIRE_SCL         (27u)

// On-board QSPI Flash
#define EXTERNAL_FLASH_DEVICES   MX25R6435F
#define EXTERNAL_FLASH_USE_QSPI

#ifdef __cplusplus
}
#endif

/*----------------------------------------------------------------------------
 *        Arduino objects - C++ only
 *----------------------------------------------------------------------------*/

#endif

Credits

JuanVi

3 projects • 5 followers

Comments

Awards

Honorable Mention Mobility Impairments

Build2gether 2.0 — Inclusive Innovation Challenge

eBook Page Turner

Things used in this project

Hardware components

Software apps and online services

Hand tools and fabrication machines

Story

Introduction

Solution:

How it Works:

Hardware:

Build Instructions

Programming the Board

Uploading the Code

Future Development:

Custom parts and enclosures

Back

Front

PCB Cover

Servo Arm (x2)

Stand 1/2

Stand 2/2

Power Switch

SolidWorks/Edge CAD Files

Schematics

Schematic Image

PCB Image

Schematic Kicad

PCB Kicad

Gerbers PCB

Code