Split power infinitely variable transmission architecture incorporating a planetary type ball variator with multiple fixed ranges and low variator load at vehicle launch

A transmission comprising:

• an input shaft configured to receive torque from a drive unit,
• an output shaft configured to transmit torque to a load,
• a variable-ratio unit arranged between the input shaft and the output shaft, and
• a plurality of torque transmitting mechanisms arranged between the input shaft and the output shaft, the plurality of torque transmitting mechanisms including a first clutch, a second clutch, a third clutch, and a fourth clutch, the transmission being operable to (i) engage the first clutch and the second clutch in a first operating mode of the transmission and (ii) engage the first clutch and the third clutch in a second operating mode of the transmission,
• wherein the transmission is further operable to (i) engage the fourth clutch and disengage the second clutch during a first period of time and (ii) engage the third clutch and disengage the fourth clutch during a second period of time following the first period of time to transition from the first operating mode to the second operating mode.