public void avancer() {
		switch (position.getDirection()) {
			case N:
				if (position.getY() < gridMaximumValueY)
					position.setY(position.getY() + 1);
				break;
			case E:
				if (position.getX() < gridMaximumValueX)
					position.setX(position.getX() + 1);
				break;
			case W:
				if (position.getX() > 0)
					position.setX(position.getX() - 1);
				break;
			case S:
				if (position.getY() > 0)
					position.setY(position.getY() - 1);
				break;
		}
	}