Disclosed herein are systems, gearing assemblies and methods for controlling a differential rotation rate between shafts of a vehicle using a variable speed reversible motor. An embodiment includes a gearing assembly including a differential configured to engage a first axle shaft, a second axle shaft, and a drive shaft of a vehicle. The gearing assembly further includes a first plurality of alignment gears and a second plurality of adjustment gears configured to engage the differential, configured to be driven by a variable speed reversible motor of the vehicle, and configured to controllably alter a rotation rate of a first axle shaft relative to a rotation rate of the second axle shaft based on rotation produced by the variable speed reversible motor.

Disclosed herein are systems, gearing assemblies and methods for controlling a differential rotation rate between shafts of a vehicle using a variable speed reversible motor. An embodiment includes a gearing assembly including a differential configured to engage a first axle shaft, a second axle shaft, and a drive shaft of a vehicle. The gearing assembly further includes a first plurality of alignment gears and a second plurality of adjustment gears configured to engage the differential, configured to be driven by a variable speed reversible motor of the vehicle, and configured to controllably alter a rotation rate of a first axle shaft relative to a rotation rate of the second axle shaft based on rotation produced by the variable speed reversible motor.

A gearbox parking brake has a gearing assembly in which two or more interconnected gears can rotate at different directions or speeds. A first and second planetary gear assembly and a central gear are concentrically positioned about a central rotation axis, and the central gear is rotatably engaged with the two planetary gear assemblies. An input is engaged with the central gear in order to operate the planetary gear assemblies, which may function as outputs. A gear engagement block is provided with sets of gear teeth corresponding to the planetary gear assemblies and the central gear. An actuator mechanism is operatively connected to the gear engagement block in order to displace the gear engagement block between a disengaged position and an engaged position. The gear teeth of the gear engagement block are meshed with the gearing assembly in the engaged position, restricting any movement of the gearing assembly.

A gearbox parking brake has a gearing assembly in which two or more interconnected gears can rotate at different directions or speeds. A first and second planetary gear assembly and a central gear are concentrically positioned about a central rotation axis, and the central gear is rotatably engaged with the two planetary gear assemblies. An input is engaged with the central gear in order to operate the planetary gear assemblies, which may function as outputs. A gear engagement block is provided with sets of gear teeth corresponding to the planetary gear assemblies and the central gear. An actuator mechanism is operatively connected to the gear engagement block in order to displace the gear engagement block between a disengaged position and an engaged position. The gear teeth of the gear engagement block are meshed with the gearing assembly in the engaged position, restricting any movement of the gearing assembly.

A vehicle drive and control system includes an input shaft driven by a prime mover and extending into a housing to drive a generator. An electric motor powered by the generator drives an output axle, which may be a single axle extending out one side of the housing, or a through shaft extending through the electric motor and out both sides of the housing. The input shaft may be parallel to the axle. A power controller is configured to back-drive the generator when certain predetermined conditions are met. A motor controller may control an output of the motor based on input received via an operator control device, and the motor controller is configured to operate the motor as a generator under certain operating conditions. The transaxle includes a common housing in which the power generator, the motor, and controllers for the generator and electric motor are disposed.

A vehicle drive and control system includes an input shaft driven by a prime mover and extending into a housing to drive a generator. An electric motor powered by the generator drives an output axle, which may be a single axle extending out one side of the housing, or a through shaft extending through the electric motor and out both sides of the housing. The input shaft may be parallel to the axle. A power controller is configured to back-drive the generator when certain predetermined conditions are met. A motor controller may control an output of the motor based on input received via an operator control device, and the motor controller is configured to operate the motor as a generator under certain operating conditions. The transaxle includes a common housing in which the power generator, the motor, and controllers for the generator and electric motor are disposed.

A system and method for differential traction drive and steering axis coordination for an autonomous mower or other turf device includes initiating a steering motion based on determining a target forward speed and a steering rotational speed, calculating a left wheel speed and a right wheel speed, and applying the left and right wheel speeds, wherein the steering rotational speed is driven by a steering motor and the traction wheels associated with the autonomous mower, and the left and right wheel speeds are based on the target forward speed, a distance from a steering axle to the center of the respective wheel, and the steering rotational speed.

A system and method for differential traction drive and steering axis coordination for an autonomous mower or other turf device includes initiating a steering motion based on determining a target forward speed and a steering rotational speed, calculating a left wheel speed and a right wheel speed, and applying the left and right wheel speeds, wherein the steering rotational speed is driven by a steering motor and the traction wheels associated with the autonomous mower, and the left and right wheel speeds are based on the target forward speed, a distance from a steering axle to the center of the respective wheel, and the steering rotational speed.

A method of controlling a vehicle during a braking operation includes providing a first and a second brake actuator, a brake input device, a steer input device, and a cross-drive transmission having two outputs and a controller. The method includes detecting a first output speed at the first output and a second output speed at the second output, and receiving a brake input request and a steer input request. The method also includes determining a differential output speed based on the first output speed and the second output speed, and comparing the differential output speed to a first threshold, the brake input request to a second threshold, and the steer input request to a third threshold. The method includes determining the first or the second output is locked during the braking operation, and controlling the first or the second brake actuator based on which output is determined to be locked.

A method of controlling a vehicle during a braking operation includes providing a first and a second brake actuator, a brake input device, a steer input device, and a cross-drive transmission having two outputs and a controller. The method includes detecting a first output speed at the first output and a second output speed at the second output, and receiving a brake input request and a steer input request. The method also includes determining a differential output speed based on the first output speed and the second output speed, and comparing the differential output speed to a first threshold, the brake input request to a second threshold, and the steer input request to a third threshold. The method includes determining the first or the second output is locked during the braking operation, and controlling the first or the second brake actuator based on which output is determined to be locked.