A drivetrain for an aircraft includes an engine, a driveshaft to receive rotational energy from the engine and a gearbox including a multistage planetary gear system to receive rotational energy from the driveshaft. The multistage planetary gear system includes an integral multistage ring gear system having flanged and cantilevered ends. The integral multistage ring gear system forms a first stage ring gear at the cantilevered end and a second stage ring gear interposed between the flanged end and the first stage ring gear. The multistage planetary gear system includes a first stage sun gear, first stage planet gears and a first stage carrier. The first stage planet gears mate with the first stage ring gear. The multistage planetary gear system includes a second stage sun gear, second stage planet gears and a second stage carrier. The second stage planet gears mate with the second stage ring gear.

A footwear system can employ a brake and/or a clutch, such as a one-way clutch, to convert human motion into usable electricity. The brake and one-way clutch can be used together, such as on opposite ends of a spring. During a storage phase, the brake can be engaged and the one-way clutch disengaged so the spring stores an energy. After the storage phase, the brake can be removed to initiate the release phase since the brake is not stopping the spring, but the one-way clutch allows the stored energy to be released.

A system and method for operating the same includes a drive sprocket assembly, a clutch lever, a user interface generating a reverse signal at a user interface, a wheel speed sensor generating a wheel speed signal, a transmission position sensor generating a transmission position signal and a vehicle control module receiving the reverse signal, the wheel speed signal and the transmission position signal. The vehicle control module engages a reverse gear at a drive sprocket in response to the reverse signal, the wheel speed and transmission gear position and controls the drive sprocket assembly in response to the clutch lever.

A power transmission apparatus of a hybrid electric vehicle may include a first shaft fixedly connected to an engine, a second shaft selectively connectable to the first shaft and fixedly connected to a motor-generator, a third shaft disposed on a same axis with the first shaft and selectively connectable to the second shaft, a fourth shaft disposed coaxially with the third shaft without rotational interference therebetween, a fifth shaft disposed in parallel with the third and fourth shafts and externally gear-meshed with the third and fourth shafts, a planetary gear set having three elements, one element being fixedly connected to the second shaft, another element being selectively connectable to a transmission housing, and a remaining element being fixedly connected to the fourth shaft, and four gear sets forming gear engagements between the first shaft, the second shaft, the third shaft, the fourth shaft and the fifth shaft.

An electric drive axle of a vehicle includes an electric motor having an output shaft. At least one of a gear and a planetary gear set is operably connected to the output shaft of the electric motor. The at least one of the gear and the planetary gear set is operably connected to a differential configured to transfer torque to two axle half shafts of the vehicle. At least one clutch configured to facilitate a plurality of gear ratios between the electric motor and the differential.

A wearable system, such as a footwear system, can employ a generator. The generator can be an electro-mechanical generator with a portion that spins to create an electricity. The portion that spins can be spun in such a manner that it does not stop, but instead a next spin beings before a previous spin completes. This can repeat until the generator reaches a terminal velocity.

A transmission system for a machine is coupled to an engine of the machine that is adapted to generate power. The transmission system includes a hydraulic power path including a variator coupled to the engine. The transmission system also includes a mechanical power path. The mechanical power path includes a first gear arrangement including a plurality of gears. The mechanical power path also includes a second gear arrangement including a plurality of gears. The second gear arrangement is coupled with the first gear arrangement to receive the variable rotational power from the first gear arrangement. The mechanical power path further includes a first clutch assembly and a second clutch assembly. Further, the second gear arrangement directs the variable rotational power received from the first gear arrangement towards a final output member of the machine in a selected direction.

A turbomachine dual spool transmission system can include a transmission assembly configured to connect to a combination output of a dual spool differential at a transmission input to be driven by the combination output to turn a transmission output. The transmission assembly can be configured to provide a first output gear ratio in a first state and a second output gear ratio in a second state. The system can include the dual spool differential. The dual spool differential can include a gear assembly configured to combine a low pressure spool input and a high pressure spool input into a combination output to provide an output speed range smaller than a low pressure speed range alone.

A drive system includes a first gear set and a second gear set, each including a sun gear, a ring gear, a plurality of planetary gears coupling the sun gear to the ring gear, and a carrier rotationally supporting the plurality of planetary gears, a first electrical machine directly coupled to the first gear set, a second electrical machine directly coupled to the second gear set, a connecting shaft directly coupled to the ring gear of the first gear set, a driveshaft that transports power from the electrical machines to a tractive element, a first clutch selectively rotationally coupling the first gear set and the second gear set to the driveshaft, and at least one of a second clutch selectively rotationally coupling the second electrical machine to the connecting shaft and a third clutch selectively rotationally coupling the second gear set to the driveshaft.

A vehicle includes a connecting shaft, a drive axle, a multi-mode transmission, and a controller. The multi-mode transmission includes a first gear set having a first planetary gear carrier and a second gear set having a second planetary gear carrier, a first motor/generator coupled to the first gear set, a second motor/generator electrically coupled to the first motor/generator and coupled to the second gear set, a brake selectively limiting movement of a portion of the second gear set, and a clutch selectively rotationally coupling the second motor/generator to the connecting shaft. The first gear set is coupled to the connecting shaft, and the planetary gear carriers are rotatably coupled. The controller is configured to selectively configure the multi-mode transmission into an active neutral startup mode of operation by engaging the clutch and the brake such that at least one of the first motor/generator and the second motor/generator produces a voltage.