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 steer-by-wire steering system for a motor vehicle with a steerable front wheel axle that has two steerable wheels. The front wheel axle includes a single wheel drive which, by means of a drive controller, individually drives wheel drives which are associated with the steerable wheels. The drive controller has a controller which determines a target speed for the left-hand wheel and a target speed for the right-hand wheel in accordance with an accelerator pedal angle and a rotational angle of a steering shaft, and which limits the target speeds to a slip-limited speed. The drive controller individually drives the wheel drives in such a way that the difference between the target speed and the actual speed for each steerable wheel is minimal.

A steer-by-wire steering system for a motor vehicle with a steerable front wheel axle that has two steerable wheels. The front wheel axle includes a single wheel drive which, by means of a drive controller, individually drives wheel drives which are associated with the steerable wheels. The drive controller has a controller which determines a target speed for the left-hand wheel and a target speed for the right-hand wheel in accordance with an accelerator pedal angle and a rotational angle of a steering shaft, and which limits the target speeds to a slip-limited speed. The drive controller individually drives the wheel drives in such a way that the difference between the target speed and the actual speed for each steerable wheel is minimal.

A hydrostatic traction drive has a steering function, which is implemented via two laterally acting secondary units (traction motors), which are supplied by a common primary unit (pump) in the open circuit. The primary unit is pressure-controlled. The two secondary units are torque-controlled. The affected vehicle is steerable as a function of a steering command by different torque specifications for the two secondary units. Furthermore, a hydrostatic drive for a mobile work machine has working hydraulics in addition to the traction drive. The working hydraulics are also supplied by the primary unit in parallel to the two secondary units.

A hydrostatic traction drive has a steering function, which is implemented via two laterally acting secondary units (traction motors), which are supplied by a common primary unit (pump) in the open circuit. The primary unit is pressure-controlled. The two secondary units are torque-controlled. The affected vehicle is steerable as a function of a steering command by different torque specifications for the two secondary units. Furthermore, a hydrostatic drive for a mobile work machine has working hydraulics in addition to the traction drive. The working hydraulics are also supplied by the primary unit in parallel to the two secondary units.

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.

A transmission for a vehicle, particularly a skid-steered vehicle, that employs motive power from a prime mover delivered through an input shaft to drive left and right drive shafts at a nominal speed and input power from an electric motor to vary the speed of the left and right drive shafts according to steering commands from a steering control structure. The speed of the left and right drive shafts is directly related to a speed of the input shaft and the nominal speed of the left or right drive shaft is varied upwardly or downwardly by a ratio of the speed of the steering shaft via a speed varying structure. The speed of the left and right drive shafts is simultaneously varied in opposite directions (i.e. upwardly and downwardly) relative to the nominal speed by an equal number of rotations.

A transmission for a vehicle, particularly a skid-steered vehicle, that employs motive power from a prime mover delivered through an input shaft to drive left and right drive shafts at a nominal speed and input power from an electric motor to vary the speed of the left and right drive shafts according to steering commands from a steering control structure. The speed of the left and right drive shafts is directly related to a speed of the input shaft and the nominal speed of the left or right drive shaft is varied upwardly or downwardly by a ratio of the speed of the steering shaft via a speed varying structure. The speed of the left and right drive shafts is simultaneously varied in opposite directions (i.e. upwardly and downwardly) relative to the nominal speed by an equal number of rotations.