ThinkUino Project

• Download source code

Introduction

ThinkUino (Thinking Arduino) is an open source project that allows to connect the Arduino board with Mindwave headset. The cognitive application opens new frontiers for control the electronic circuits through the reading of brainwaves. With this article I explain how to make a cognitive application for control a single LED light.

Background

Mindwave... what is it?

Mindwave is an innovative headset produced by Neurosky. Mindwave converts the brainwaves into digital electronic signals. There are two version of this device:

• Mindwave Headset: is the basic configuration of Mindwave. It can be connected only to pc for reading data only with Neurosky applications. Its color is white. You can buy it from this link: http://store-eu.neurosky.com/collections/hardware/products/mindwave-1

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• Mindwave Mobile Headset: this version allow to connect with mobile device through bluetooth SPP communication. This device retrieves the brainwaves with more precision. This device, than, can be connected to Android and iOS operating system. Its color is black. You can buy it form this link: http://store-eu.neurosky.com/collections/hardware/products/mindwave-mobile

Mindwave... two versions, but which i should choose?

For the scope of this project the Mindwave Mobile is indispensable. That device supports the bluetooth connection, through the bluetooth connection it send the data in RAW mode to the connected devices. With the retrieved data we can parse the various frequency reading by the headset.

What do i need to implement this project?

The fundamental elements to create this project are:

1. Mindwave Mobile Headset
2. Arduino 2009 or higher
3. Led

Using the code

Follow the below steps to create the architecture of this project.

Configure the Arduino board:

Connect the LED light on the board. Insert the anode in the thirteenth pin (called pin Led) and the cathode in the GND (ground) pin. See the picture below if you have doubts:

After that, connect the Arduino to USB port and upload this code:

int val;  
void setup() 
{ 
  Serial.begin(9600);
  pinMode(13,OUTPUT);
} 
 
void loop() 
{ 
  if(Serial.available()>0){
    val = Serial.read();
    if(val==1){
     digitalWrite(13,HIGH);
    }else{
      digitalWrite(13,LOW);
    }  
}

As you can see, the code is so simply. The board read a single byte set the LED, then:

• byte is set to 0: set the pin led to LOW
• byte is set to 1: set the pin led to HIGH

Configure the Mindwave headset:

For first we must pairing the bluetooth headset to the computer. Follow this step for pairing the device:

• Set the headset in discoverable mode. Hold the button for three seconds. See the below image:

• Open the Bluetooth option on control panel and search all discoverable device, when the headset, named MindWave Mobile, if is on the list, add it.

Now.. let's analyze the code!

You can to download the source code from this article, see the attachments..

This project uses the ThinkGear.net library. This library retrieved the RAW data from the headset and parse it, than we can to access with simplicity to all frequency and states. The headset uses the eSense protocol. The eSense elaborates all frequency and returns two type of state, Attention and Meditation. We use the Attention variable to change the led's state.

See the comment in the code for understand it:

using System;
using System.Collections.Generic;
using System.ComponentModel;
using System.Data;
using System.Drawing;
using System.Linq;
using System.Text;
using System.Windows.Forms;
using ThinkGearNET;
using System.Threading;
using System.IO;
 
namespace ThinkUino
{
    public partial class Form1 : Form
    {
        
        private ThinkGearWrapper thinkGearWrapper = new ThinkGearWrapper(); //declare the thinkgear object
        private bool comando = false;
 
        private const string ARDUPORT = "COM5"; //declare the arduino serial port
        private const string MINDPORT = "COM7"; //declare the Mindwave serial port

        public Form1()
        {
           InitializeComponent();
        }
 
        private void btnHeadsetConnect_Click(object sender, EventArgs e)
        {
            if (thinkGearWrapper.Connect(MINDPORT, 57600, true)) //check if the Mindwave is connected
            {
                btnHeadsetConnect.Enabled = false; //disable connect button
                btnHeadsetDisconnect.Enabled = true; //enable disconnect button
                txtHeadsetDebug.AppendText("Headset connected." + Environment.NewLine);
                thinkGearWrapper.EnableBlinkDetection(true); //enable the eye blink on the eSense protocol
                thinkGearWrapper.ThinkGearChanged += new EventHandler<ThinkGearChangedEventArgs>(
                  thinkGearWrapper_ThinkGearChanged); //capture the event when a new data is incoming
            }
            else
                txtHeadsetDebug.AppendText("Could not connect to headset" + Environment.NewLine);
        }
 
        void thinkGearWrapper_ThinkGearChanged(object sender, ThinkGearChangedEventArgs e)
        {
            
            BeginInvoke(new MethodInvoker(delegate //use the AsyncTask to update the UI
                {
                    if ((thinkGearWrapper.ThinkGearState.BlinkStrength > 60)  ) // check if the eye blink strength is above 60
                    {
                        comando = !comando; //switch the led's state
                        txtHeadsetDebug.AppendText("Command: " + Convert.ToByte(comando) + Environment.NewLine); 
                        thinkGearWrapper.ThinkGearState.BlinkStrength = 0;//set the eye blink strength to zero
                    }
                    if (thinkGearWrapper.ThinkGearState.Attention > 60)//check if the Attention state is above 60
                    {
                        serialArduino.Write(new byte[] { Convert.ToByte(comando) }, 0, 1); //send the commando to arduino serial port
                        txtHeadsetDebug.AppendText("Command sendend: " + Convert.ToByte(comando) + Environment.NewLine);
                        txtArduinoDebug.AppendText("Command received: " +Convert.ToByte(comando));
                        thinkGearWrapper.ThinkGearState.Attention = 0; //set the attention state to zero
                    }
                    lblAttention.Text = "Attention: " + thinkGearWrapper.ThinkGearState.Attention;
                    lblMeditation.Text = "Meditation: " + thinkGearWrapper.ThinkGearState.Meditation;
                }));
            Thread.Sleep(10); //wait ten milliseconds
        }
 
        private void btnHeadsetDisconnect_Click(object sender, EventArgs e)
        {
            
            thinkGearWrapper.Disconnect(); //close the headset connection
            txtHeadsetDebug.AppendText("Disconnected." + Environment.NewLine);
            btnHeadsetDisconnect.Enabled = false; //disable the headset disconnect button
            btnHeadsetConnect.Enabled = true; //enable the headset connect button
        }
 
        private void bntArduinoConnect_Click(object sender, EventArgs e)
        {
            try
            {
                serialArduino.PortName = ARDUPORT; //set the arduino serial port name
                serialArduino.Open(); //open the communication
                txtArduinoDebug.AppendText("Arduino connected" + Environment.NewLine);
                btnArduinoDisconnect.Enabled = true; //enable the arduino disconnect button
                btnArduinoConnect.Enabled = false; //disable the arduino connect button
            }
            catch (IOException)
            {
                txtArduinoDebug.AppendText("Could not connect to Arduino" + Environment.NewLine);
            }
               
        }
 
        private void btnArduinoDisconnect_Click(object sender, EventArgs e)
        {
            if (serialArduino.IsOpen) //check if the communication is open
            {
                serialArduino.Close(); //close the arduino communication
                txtArduinoDebug.AppendText("Disconnected." + Environment.NewLine);
                btnArduinoConnect.Enabled = true; //enable the arduino connect button
                btnArduinoDisconnect.Enabled = false; //disable the arduino disconnect button
            }
        }
 
    }
} 

The application has only one window:

To use correctly the application connect for first the devices, Mindwave and Arduino, than click on the both button on the window. Blink your eyes to change the led's state and erase from your mind all the think, except the LED!!

Bye!