A crawler vehicle having a first and second track driven by a first and second drive wheel respectively; an internal combustion engine; a mechanical power transmission assembly extending from the internal combustion engine to the first and second drive wheel; an electric power transmission assembly; a mechanical power connection configured to transfer energy between the mechanical power transmission assembly and the electric power transmission assembly; and at least one mechanical power transmission configured to transfer energy between the electric power transmission assembly and the mechanical power transmission assembly; the electric power transmission assembly extending from the mechanical power connection to the mechanical power transmission.

Gearboxes for a skid steered vehicle including layouts in which all electric propulsion drive motors and electric steering motors are located on one side of the gearbox, and layouts in which the drive inputs of the electric propulsion drive motors are located face to face. Gear change units and gear packaging configurations suitable for such gearboxes.

Gearboxes for a skid steered vehicle including layouts in which all electric propulsion drive motors and electric steering motors are located on one side of the gearbox, and layouts in which the drive inputs of the electric propulsion drive motors are located face to face. Gear change units and gear packaging configurations suitable for such gearboxes.

An electric crawler vehicle includes a pair of left and right traveling crawlers, a traveling electric motor that generates traveling power to be transmitted to the pair of left and right traveling crawlers, and a turning electric motor that generates turning power to be transmitted to the pair of left and right traveling crawlers. The traveling electric motor and the turning electric motor are disposed on one lateral side of the vehicle.

An electric crawler vehicle includes a pair of left and right traveling crawlers, a traveling electric motor that generates traveling power to be transmitted to the pair of left and right traveling crawlers, and a turning electric motor that generates turning power to be transmitted to the pair of left and right traveling crawlers. The traveling electric motor and the turning electric motor are disposed on one lateral side of the vehicle.

An electric crawler vehicle comprising a pair of left and right traveling crawlers, each having a drive wheel, a traveling electric motor that generates traveling power to be transmitted to the pair of left and right traveling crawlers, a turning electric motor that generates turning power to be transmitted to the pair of left and right traveling crawlers, and a differential mechanism disposed in a power transmission path between the turning electric motor and each drive wheel of the pair of left and right traveling crawlers.

A drive unit for a skid steered vehicle includes a controlled differential positioned between two shafts. The end of each shaft forms an output of the drive unit connected directly to the differential outputs via the shafts. A steer motor is in driveable communication with the differential, and an electric propulsion motor is in driveable communication with the shaft outputs. A gear reduction unit, and optional gear change unit, is positioned between the differential and the electric propulsion motor. The electric propulsion motor, the gear reduction unit and optional gear change unit are connected in a parallel connection with an output of the differential to the shaft outputs. The optional gear change unit includes an epicyclic gear reduction unit having an input and an output which provides drive input from the gear change unit to the shaft. A gear change set has a master gear that receives drive output from the electric propulsion motor, and slave gears which are driven by the master gear via one or more gear chains. A dog clutch slideably engages the input of the gear reduction unit and selectively engages with the master gear or slave gears so that the selected position of the dog clutch determines which gear is engaged.

A drive unit for a skid steered vehicle includes a controlled differential positioned between two shafts. The end of each shaft forms an output of the drive unit connected directly to the differential outputs via the shafts. A steer motor is in driveable communication with the differential, and an electric propulsion motor is in driveable communication with the shaft outputs. A gear reduction unit, and optional gear change unit, is positioned between the differential and the electric propulsion motor. The electric propulsion motor, the gear reduction unit and optional gear change unit are connected in a parallel connection with an output of the differential to the shaft outputs. The optional gear change unit includes an epicyclic gear reduction unit having an input and an output which provides drive input from the gear change unit to the shaft. A gear change set has a master gear that receives drive output from the electric propulsion motor, and slave gears which are driven by the master gear via one or more gear chains. A dog clutch slideably engages the input of the gear reduction unit and selectively engages with the master gear or slave gears so that the selected position of the dog clutch determines which gear is engaged.