Methods and systems for a vehicle transmission are provided. In one example, a vehicle transmission system includes a first planetary gear set rotationally coupled to a second planetary gear set and a first electrical machine rotationally coupled to a gear in the first planetary gear set. The vehicle transmission system further includes a second electrical machine rotationally coupled to a gear in the second planetary gear set and a first clutch configured to selectively disconnect the first and second planetary gear sets from a drive axle.

Methods and systems for a vehicle transmission are provided. In one example, a vehicle transmission system includes a first planetary gear set rotationally coupled to a second planetary gear set and a first electrical machine rotationally coupled to a gear in the first planetary gear set. The vehicle transmission system further includes a second electrical machine rotationally coupled to a gear in the second planetary gear set and a first clutch configured to selectively disconnect the first and second planetary gear sets from a drive axle.

Methods and systems for a vehicle transmission are provided. In one example, a vehicle transmission system includes a first planetary gear set rotationally coupled to a second planetary gear set and a first electrical machine rotationally coupled to a gear in the first planetary gear set. The vehicle transmission system further includes a second electrical machine rotationally coupled to a gear in the second planetary gear set and a first clutch configured to selectively disconnect the first and second planetary gear sets from a drive axle.

An electric powertrain includes a first electric motor that has an uninterrupted connection with a drive shaft of a vehicle. The electric powertrain further includes a first gear train that has an interruptible connection with the drive shaft. In one form, this interruptible connection includes a second carrier and a clutch engagement member. The electric powertrain further includes a sun gear in the form of a ring gear and planet gears in the form of a first output shaft. To provide a compact configuration, the first electric motor and the first gear train are sandwiched between the sun gear and the planet gears.

A speed-change mechanism includes an output shaft on which a transmission module and a speed step-up module are mounted. The transmission module includes a driving roller that drives the output shaft in a single direction. The speed step-up module includes a connecting gear and a speed step-up gear that are rotatably and fixedly mounted to the output shaft, respectively, and a planet speed-change wheel assembly arranged therebetween. The speed step-up module includes an arrestor assembly. At a low speed, the planet speed-change wheel assembly is idling as being set in an orbiting motion and input power is suppled through the driving roller driving the output shaft in the single direction; and at a high speed, the arrestor assembly stops the orbiting motion of the planet speed-change wheel assembly to allow the speed-change gear of the planet speed-change wheel assembly to switch to a spinning motion to step up the speed.

A speed-change mechanism includes an output shaft on which a transmission module and a speed step-up module are mounted. The transmission module includes a driving roller that drives the output shaft in a single direction. The speed step-up module includes a connecting gear and a speed step-up gear that are rotatably and fixedly mounted to the output shaft, respectively, and a planet speed-change wheel assembly arranged therebetween. The speed step-up module includes an arrestor assembly. At a low speed, the planet speed-change wheel assembly is idling as being set in an orbiting motion and input power is suppled through the driving roller driving the output shaft in the single direction; and at a high speed, the arrestor assembly stops the orbiting motion of the planet speed-change wheel assembly to allow the speed-change gear of the planet speed-change wheel assembly to switch to a spinning motion to step up the speed.

The present disclosure provides a power unit for a bionic robot, a robot joint and a robot. The power unit comprises: a shell, wherein a stator is embedded in the shell, a rotor is embedded in the stator, a rotor shaft is embedded in the rotor, bearings are disposed between the rotor shaft and the shell, a driving shaft is embedded in a central portion of the rotor shaft, a first driving wheel is disposed on the driving shaft, two transmission shafts are disposed in the rotor shaft, a first driven wheel and second driving wheels are disposed on each of the transmission shafts, the first driven wheel is engaged with the first driving wheel, a sun gear shaft is disposed in the rotor shaft, the sun gear shaft and the driving shaft are coaxially disposed, and a synchronizer and second driven wheels are disposed on the sun gear shaft.

An epicyclic gear train includes a housing, an input shaft, a first sun gear fixedly connected to the input shaft, an output shaft, a second sun gear fixedly connected to the output shaft, a planetary gear carrier arranged to be movable with respect to the first and second sun gears, and first and second planetary gears arranged to move on the planetary gear carrier. The planetary gears are fixedly connected to one another and disposed in engagement with the first and second sun gears, The epicyclic gear train further includes a first clutch device is disposed between the planetary gear carrier and the first sun gear, and a second clutch device is disposed between the housing and the planetary gear carrier. The first and second clutch devices block a relative movement between the planetary gear carrier and the first sun gear or between the planetary gear carrier and the housing.

An epicyclic gear train includes a housing, an input shaft, a first sun gear fixedly connected to the input shaft, an output shaft, a second sun gear fixedly connected to the output shaft, a planetary gear carrier arranged to be movable with respect to the first and second sun gears, and first and second planetary gears arranged to move on the planetary gear carrier. The planetary gears are fixedly connected to one another and disposed in engagement with the first and second sun gears, The epicyclic gear train further includes a first clutch device is disposed between the planetary gear carrier and the first sun gear, and a second clutch device is disposed between the housing and the planetary gear carrier. The first and second clutch devices block a relative movement between the planetary gear carrier and the first sun gear or between the planetary gear carrier and the housing.

An electric powertrain includes a first electric motor that has an uninterrupted connection with a drive shaft of a vehicle. The electric powertrain further includes a first gear train that has an interruptible connection with the drive shaft. In one form, this interruptible connection includes a second carrier and a clutch engagement member. The electric powertrain further includes a sun gear in the form of a ring gear and planet gears in the form of a first output shaft. To provide a compact configuration, the first electric motor and the first gear train are sandwiched between the sun gear and the planet gears.