Android: Using the accelerometer to detect a flick -

i'm trying develop app user can hit invisible drum using motion of phone. when phone flicked downwards drum sounded @ end of flick.

i have managed 90% of working, detecting when large, quick movement stops. although drum being sounded after flick (good) it's being sounded @ end of pull (not desirable).

by flick mean phone being flicked forwards , downwards, if striking drum it, , pull mean returning arm starting position.

does know efficient way of determining when flick occurs not push?

any ideas gratefully received.

thanks

existing code:

package com.example.testaccelerometer;  import android.hardware.sensor; import android.hardware.sensorevent; import android.hardware.sensoreventlistener; import android.hardware.sensorlistener; import android.hardware.sensormanager; import android.os.bundle; import android.app.activity; import android.content.context; import android.view.menu; import android.widget.textview;  public class mainactivity extends activity implements sensoreventlistener{      public static textview results;      public static textview clickresults;      stringbuilder builder = new stringbuilder();        private float maccelnograv;       private float maccelwithgrav;       private float mlastaccelwithgrav;      public static boolean shakeishappening;     public static int beatnumber = 0;       @override     protected void oncreate(bundle savedinstancestate) {         super.oncreate(savedinstancestate);         setcontentview(r.layout.activity_main);          results = (textview) findviewbyid(r.id.results);         clickresults = (textview) findviewbyid(r.id.clickresults);          sensormanager manager = (sensormanager) getsystemservice(context.sensor_service);         sensor accelerometer = manager.getdefaultsensor(sensor.type_accelerometer);          if(!manager.registerlistener(this, accelerometer, sensormanager.sensor_delay_fastest)){             builder.append("problem accelerometer - shaking not work");         };           maccelnograv = 0.00f;         maccelwithgrav = sensormanager.gravity_earth;         mlastaccelwithgrav = sensormanager.gravity_earth;        }      @override     public boolean oncreateoptionsmenu(menu menu) {         // inflate menu; adds items action bar if present.         getmenuinflater().inflate(r.menu.main, menu);         return true;     }      @override     public void onaccuracychanged(sensor sensor, int accuracy) {         // todo auto-generated method stub      }      @override     public void onsensorchanged(sensorevent event) {         builder.setlength(0);         builder.append("x " + event.values[0] + "\ny " + event.values[1] + "\nz " + event.values[2]);     results.settext(builder.tostring());           float x = event.values[0];           float y = event.values[1];           float z = event.values[2];           mlastaccelwithgrav = maccelwithgrav;           maccelwithgrav = android.util.floatmath.sqrt(x*x + y*y + z*z);           float delta = maccelwithgrav - mlastaccelwithgrav;           maccelnograv = maccelnograv * 0.9f + delta;      if (maccelnograv >8.5) {         shakeishappening = true;         //clickresults.append(" click " + maccel);     }      if (shakeishappening == true && maccelnograv <2) {         beatnumber++; clickresults.append(" click number: " + beatnumber + "\n" + "pa: " + mlastaccelwithgrav + " ca:" + maccelnograv + "\n "); shakeishappening = false;     }      }       @override     protected void onresume() {       super.onresume();     // need try , reregister     }      @override     protected void onpause() {         // need try , unregister       super.onpause();     }   } 

you can use geo-magnet sensor in conjunction accelerometer sensor determine edge of device facing toward ground, , exclude acceleration events in opposite direction

http://developer.android.com/reference/android/hardware/sensormanager.html#getorientation(float[], float[])