Planetary gear train of automatic transmission for vehicle

A planetary gear train of an automatic transmission for a vehicle, comprising:

• an input shaft for receiving torque from an engine;
• an output shaft for outputting a shifted torque;
• a first planetary gear set having first, second, and third rotational elements;
• a second planetary gear set having fourth, fifth, and sixth rotational elements;
• a third planetary gear set having seventh, eighth, and ninth rotational elements;
• a fourth planetary gear set having tenth, eleventh, and twelfth rotational elements;
• a first shaft fixedly connected with the first rotational element and the sixth rotational element, and selectively connected with the input shaft;
• a second shaft fixedly connected with the ninth rotational element and selectively connected with the input shaft;
• a third shaft fixedly connected with the eleventh rotational element and fixedly connected with the output shaft;
• a fourth shaft fixedly connected with the second rotational element, the fifth rotational element, and the twelfth rotational element;
• a fifth shaft fixedly connected with the fourth rotational element and the seventh rotational element;
• and
• a plurality of additional shafts each selectively connecting a corresponding element to a transmission housing, the corresponding element being a rotational element of the first, third, and fourth planetary gear sets that is not fixedly interconnected.