private void turnRight() {
        switch (direction) {
            case 'N':
                direction = 'E';
                break;
            case 'W':
                direction = 'N';
                break;
            case 'S':
                direction = 'W';
                break;
            case 'E':
                direction = 'S';
                break;
            default:
                break;
        }
    }