private void onBeatStarted(Signal signal)
 {
     if (!gameIsOver)
     {
         BeatStartedSignal beatStartedSignal = (BeatStartedSignal)signal;
         if (beatStartedSignal.BeatType == BeatType.ROBOT_MOVE)
         {
             ItemIcon newItemIcon = ItemIconPool.Inst.GetRandomItemIcon();
             newItemIcon.Activate(this);
         }
     }
 }