EMDR Psychotherapy Light Bar

Building a therapy device for my psychotherapist wife was a nice mix of programming, electronics and woodworking.

BeginnerFull instructions provided519

Things used in this project

Hardware components

Arduino UNO

10mm Warm White LED

10mm LED Clip Holder

Rotary potentiometer (generic)

Resistor 330 ohm

Breadboard (generic)

Story

The idea: moving light bar to support psychotherapy method

My wife is a psychotherapist and she is using a technique called Eye Movement Desensitization and Reprocessing (EMDR). In EMDR, the person being treated recalls distressing experiences whilst doing bilateral stimulation, such as side-to-side eye movement or physical stimulation, such as tapping either side of the body.

My wife used to move her finger from side to side and had patient's eyes follow it. But as this can be quite distracting, she asked my to build something that stimulates the patient's eye movement without her having to do it.

I came up with the idea of an "light bar" or series of lamps or diodes that are programmed to light up in sequence to create a moving light point.

This is what I had in mind:

A number of LEDs in a row - and the light is "moving" from LED to LED and back to induce side-to-side eye movement.

Brightness of LEDs and speed of movement to be adjusted with potentiometers

Must look nice enough to fit in a cozy therapy room

Proof of concept

While I was already looking forward to the woodworking part, I first built a proof of concept on my desk - just the electronics and programming.

I was wondering if I needed to analogwrite to the LEDs in order to dim and smoothen the movement. But it turns out that just switching the LEDs on and off one after another is just fine. So I used digital write instead.

As I needed no other pins, I used all 14 just to trigger the LEDs.

The brightness potentiometer is sitting between the LEDs and their joint GND - series-wired with a 330 Ohm resistor. Changing the resistor to a different one will change the brightness.

The speed potentiometer is read through an analog pin. While building I was writing the value to Serial.println for debugging. You can still see it in the code.

Building a casing

I built a prelinary version just with a raw piece of wood to get an idea for the ideal measurements. But ultimately the device has to look nice in my wife's therapy room and not distract patients with wires and stuff poking out. So I create a housing out of beech wood.

Glueing the beechwood casing

I am not a good woodworker. But I enjoy building stuff from wood. And practice makes perfect.

After the casing was done, I moved the prepared electronics pieces into the casing...

...and we're done. For the power supply I added a long cable and a switch to the 9V adaptor, so that the device can be switched on and off while sitting down.

In the back you can see a raw board that I used for an intermediate version.

Code

sfr_EMDR_v03.ino

// EMDR Therapy Tool
// v01 - Light is "moving" from LED to LED, speed can be adjusted with poti
// v02 - Brightness can also be adjusted with poti
// v03 - Using Poti as a hardware adjustable resistor instead of analogWrite for Brightness adjustment



// Light variables

int activeLED = 0;
int duration = 500;
int updown = 0;     // 0 = Aufwrts laufen, 1 = abwrts
int minLED = 1;    
unsigned long counterStart = millis();
int brightness = 255;

// Poti variables

int potiSpeed= A5; 
int potiSpeedValue = 0; 


void setup() {
  pinMode(13, OUTPUT);
  pinMode(12, OUTPUT);
  pinMode(11, OUTPUT);
  pinMode(10, OUTPUT);
  pinMode(9, OUTPUT);
  pinMode(8, OUTPUT);
  pinMode(7, OUTPUT);
  pinMode(6, OUTPUT);
  pinMode(5, OUTPUT);
  pinMode(4, OUTPUT);
  pinMode(3, OUTPUT);
  pinMode(2, OUTPUT);
  pinMode(1, OUTPUT);
  pinMode(0, OUTPUT);

  // Serial.begin(9600);   // For debugging, can be deactivated, observation: Calling Serial will enable TX/RX on PIN 0 and 1
}


void loop() {

  // Read Speed Poti 
  potiSpeedValue = analogRead(potiSpeed);  
  duration = map(potiSpeedValue,0,1023,5,200); // So that the speed does not start at unreasonably low, and does not go up to 0 (=permanent)
  // Serial.println(potiSpeedValue);  // For debugging, can be deactivated
  
  digitalWrite(activeLED, HIGH ); // Turn active LED on
  
  counterStart = millis();
  
  while (millis()-counterStart < duration) {
  }

  digitalWrite (activeLED, LOW); // Turn active LED off

  if ((activeLED <=12) && (updown == 0)) {
    activeLED++;
  
  }
  
  else if ((activeLED >= minLED) && (updown == 1))  { 
    activeLED--;
  }
  
  else if ((activeLED < minLED) && (updown == 1)) {
    activeLED = minLED;
    updown = 0;
  }
  
  else {
    activeLED=12;
    updown = 1;
  } 

}

Credits

hobooeconomicus

1 project • 0 followers

EMDR Psychotherapy Light Bar