Android Detect Sleep Movement

Follow up from: http://jvyloh.blogspot.com/2009/07/record-sleep-cycle-using-android.html

There are enquiries / requests for the app / source code. I am posting some code snippets to help you get started implementing a better Sleep Cycle Detector. You are welcome to comment on it and suggest improvement. Kindly post me a link to your better app so I can try it out :-)

Well, I have no plan to publish the app as I am busy on other projects, it remains as a proof-of-concept. There are similar apps in the Android Market, one of them is by Alexander Kosenkov called Smart Alarm Clock for Android.

I also found some other code example here: http://www.clingmarks.com/?p=25

Code snippets:

1. Get the 'Sensor Service', e.g.:

SensorManager senMgr = (SensorManager)getSystemService(Context.SENSOR_SERVICE);

2. Register Sensor Listener, and set how often you like to receive events, e.g.:

senMgr.registerListener(sensorEvtLsnr, sensor, SensorManager.SENSOR_DELAY_NORMAL);

3. Create the Sensor Listener, e.g.:

private SensorEventListener sensorEvtLsnr = new SensorEventListener()

{

//your code here

};

4. Override the method that receive the sensor events:

private SensorEventListener sensorEvtLsnr = new SensorEventListener() {

@Override

public void onSensorChanged(SensorEvent evt)

{

//your code here

}

};

5. Listen to the type sensor event you interested, in this case:

• Sensor.TYPE_ACCELEROMETER

There are other sensor type which are applicable for different application:

• Sensor.TYPE_MAGNETIC_FIELD
• Sensor.TYPE_ORIENTATION

6. Implement your algorithm what you consider a movement, for my simple POC, I monitor the change in the ACCELEROMETER X value, a change of value to consider a movement count, and I have a timer that gathers the number of movement count per minute, which you can use to plot a graph, persist to a file or post to the cloud.

int cAccX, //movement count per minute

float accX; //accelerometer x value

TextView tvAccelerometer; //TextView to show display data on screen

private SensorEventListener sensorEvtLsnr = new SensorEventListener() {

@Override

public void onSensorChanged(SensorEvent evt)

{

if(evt.sensor.getType() == Sensor.TYPE_ACCELEROMETER ){

if(accX != evt.values[0]){

accX = evt.values[0];

cAccX++;

tvAccelerometer.setText("Accelerometer[x] = " + cAccX + " = " + accX );

}

}

}

};