Bi-directional rotary speed conversion via mirrored rotational power transfer tunnel

An apparatus, comprising:

• a first rotatable shaft coupled to a second rotatable shaft and to a third rotatable shaft;
• a fourth rotatable shaft coupled to a fifth rotatable shaft and to a sixth rotatable shaft;
• a first differential coupled to the second rotatable shaft and to a thirteenth rotatable shaft;
• a second differential coupled to the third rotatable shaft and to the sixth rotatable shaft;
• a seventh rotatable shaft coupled to the first differential;
• an eighth rotatable shaft coupled to the second differential;
• a first torque and/or speed converter coupled to the seventh rotatable shaft;
• a second torque and/or speed converter coupled to the eighth rotatable shaft;
• a ninth rotatable shaft coupled to the first torque and/or speed converter;
• a tenth rotatable shaft coupled to the second torque and/or speed converter;
• an eleventh rotatable shaft coupled to the ninth rotatable shaft and to the tenth rotatable shaft;
• a third differential coupled to a twelfth rotatable shaft and to a fourteenth rotatable shaft;
• a fourth differential coupled to a fifteenth rotatable shaft and to the fifth rotatable shaft;
• a sixteenth rotatable shaft coupled to the third differential;
• a seventeenth rotatable shaft coupled to the fourth differential;
• a third torque and/or speed converter coupled to the sixteenth rotatable shaft;
• a fourth torque and/or speed converter coupled to the seventeenth rotatable shaft;
• an eighteenth rotatable shaft coupled to the third torque and/or speed converter and to both the ninth rotatable shaft and the eleventh rotatable shaft;
• a nineteenth rotatable shaft coupled to the fourth torque and/or speed converter and to both the ninth rotatable shaft and the eleventh rotatable shaft;
• at least one one-way bearing/coupling-uncoupling device coupled to at least one of the first rotatable shaft, the second rotatable shaft, the third rotatable shaft, the fourteenth rotatable shaft, the fifteenth rotatable shaft, a twentieth rotatable shaft, and a twenty first rotatable shaft;
• and
• at least one an other one-way bearing/coupling-uncoupling device coupled to at least one of the fourth rotatable shaft, the fifth rotatable shaft, the sixth rotatable shaft, the twelfth rotatable shaft, the thirteenth rotatable shaft, a twenty second rotatable shaft, and a twenty third rotatable shaft.