A transmission assembly comprising: a transmission housing; a first ring-carrier/ring-carrier gearset including a first sun gear, a first carrier, and a first ring gear disposed within said transmission housing; a second ring-carrier/ring-carrier gearset including a second sun gear, a second carrier and a second ring gear disposed within said transmission housing adjacent said first ring-carrier/ring-carrier gearset; an output shaft connected to said first ring gear of said first ring-carrier/ring-carrier gearset and said second carrier of said second ring-carrier/ring-carrier gearset; a first input shaft connected to said second sun gear of said second ring-carrier/ring-carrier gearset; a first controllable clutch connected to said first sun gear of said first ring-carrier/ring-carrier gearset; a second input shaft connected to said first controllable clutch such that said first controllable clutch selectively couples said second input shaft to said first sun gear of said first ring-carrier/ring-carrier gearset; a second controllable clutch selectively coupling said second input shaft with said output shaft through said first ring gear of said first ring-carrier/ring-carrier gearset and said second carrier of said second ring-carrier/ring-carrier gearset; a first controllable brake selectively coupling said first sun gear to said transmission housing; and a second controllable brake selectively coupling said first carrier of said first ring-carrier/ring-carrier gearset and said second ring gear of said second ring-carrier/ring-carrier gearset to said transmission housing, such that said first and second controllable clutches (140, 142) and said first and second controllable brakes (76, 92) control the torque of said output shaft as a function of forces driving said first and second input shafts (44, 126). a transmission housing; a first ring-carrier/ring-carrier gearset including a first sun gear, a first carrier, and a first ring gear disposed within said transmission housing; a second ring-carrier/ring-carrier gearset including a second sun gear, a second carrier and a second ring gear disposed within said transmission housing adjacent said first ring-carrier/ring-carrier gearset; an output shaft connected to said first ring gear of said first ring-carrier/ring-carrier gearset and said second carrier of said second ring-carrier/ring-carrier gearset; a first input shaft connected to said second sun gear of said second ring-carrier/ring-carrier gearset; a first controllable clutch connected to said first sun gear of said first ring-carrier/ring-carrier gearset; a second input shaft connected to said first controllable clutch such that said first controllable clutch selectively couples said second input shaft to said first sun gear of said first ring-carrier/ring-carrier gearset; a second controllable clutch selectively coupling said second input shaft with said output shaft through said first ring gear of said first ring-carrier/ring-carrier gearset and said second carrier of said second ring-carrier/ring-carrier gearset; a first controllable brake selectively coupling said first sun gear to said transmission housing; and a second controllable brake selectively coupling said first carrier of said first ring-carrier/ring-carrier gearset and said second ring gear of said second ring-carrier/ring-carrier gearset to said transmission housing, such that said first and second controllable clutches (140, 142) and said first and second controllable brakes (76, 92) control the torque of said output shaft as a function of forces driving said first and second input shafts (44, 126).