private void movement(){
		if(Greenfoot.isKeyDown("up")){
			this.move(MOVE_SPEED);
		}
		if(Greenfoot.isKeyDown("left")){
			this.setLocation(this.getX()-MOVE_SPEED, this.getY());
		}
		if(Greenfoot.isKeyDown("right")){
			this.setLocation(this.getX()+MOVE_SPEED, this.getY());

		}
		if(Greenfoot.isKeyDown("down")){
			this.move(-MOVE_SPEED);
		}
	}