A self-propelled harvesting machine includes a front harvesting attachment, a ground drive with first and second drive shafts offset relative to the front harvesting attachment, first and second track roller units to which first and second drive shafts are drivably connected and which extend on both sides of the harvesting machine and a rear axle having rear wheels that are steered via a steering mechanism provided in a rear region of the harvesting machine. The first and second drive shafts are driven by separate first and second hydraulic motors of a hydrostatic transmission. A displacement volume of each of the first and second hydraulic motors is changed depending on a steering movement transferred from the steering mechanism to the rear wheels, realizing an additional moment about a vertical axis of the harvesting machine simultaneously with the steering of the rear wheels.

A self-propelled harvesting machine includes a front harvesting attachment, a ground drive with first and second drive shafts offset relative to the front harvesting attachment, first and second track roller units to which first and second drive shafts are drivably connected and which extend on both sides of the harvesting machine and a rear axle having rear wheels that are steered via a steering mechanism provided in a rear region of the harvesting machine. The first and second drive shafts are driven by separate first and second hydraulic motors of a hydrostatic transmission. A displacement volume of each of the first and second hydraulic motors is changed depending on a steering movement transferred from the steering mechanism to the rear wheels, realizing an additional moment about a vertical axis of the harvesting machine simultaneously with the steering of the rear wheels.

A zero turn radius vehicle with a single steered wheel is described. The vehicle may include a pair of power transfer mechanisms driving a pair of wheels, an operator control mechanism for controlling the steering, speed and direction of the vehicle and a controller in communication with the operator control mechanism. A steerable wheel is located adjacent the front of the vehicle frame, on a first side of the vehicle frame and an electric actuator is connected to the controller for steering the front steerable wheel. A second, non-steerable front caster wheel is located on a second side of the vehicle frame. The controller controls the pair of power transfer mechanisms and the electric actuator based on operator input to the operator control mechanism.

Vehicle drive control systems, such as those, for example, configured to permit a vehicle to direct power to at least one drivable element (such as, for example, via a drive shaft, a supplemental drive, or a battery) to assist the vehicle in making a low-radius turn.

Vehicle drive control systems, such as those, for example, configured to permit a vehicle to direct power to at least one drivable element (such as, for example, via a drive shaft, a supplemental drive, or a battery) to assist the vehicle in making a low-radius turn.

A vehicle includes a rear axle having wheels, friction brakes associated with the wheels, and a driver-actuatable input. A vehicle controller is programmed to, in response to the vehicle being in drift mode and the driver-actuatable input being actuated: command zero torque to the wheels, regardless of a driver-demanded torque, for a duration of time; command engagement of the friction brakes responsive to the duration of time ending; and command torque to the wheels responsive to a speed of the wheels being less than a threshold.

An identical steer control mechanism of a radial bar-link trapezoidal swing arm, a method and a multi-wheel vehicle thereof are disclosed. The radial bar-link trapezoidal swing arm is in a right triangle shape, and in combination with a two-dimensional composite control transmission arm of a cross-shaped groove formed by a transverse groove and a vertical groove, an elliptical gauge is shaped; the longitudinal cosine displacement is controlled by the sliders in the transverse groove, and the transverse sine displacement can be controlled by connecting the sliders in the vertical groove after the right-angle end bearing is hinged to connecting rods, the end bearing on the two-dimensional composite control transmission arm, namely the key control point bearing, draws a deflection elliptical trajectory, and the hinged slider to the key control point bearing is connected with a vector control swing arm sliding slot to generate a steering angle βi.

In some embodiments, a vehicle may include a frame having longitudinal axis. The vehicle may include a steering assembly having a steering input and at least one wheel. The steering assembly may be coupled to the frame and configured to steer the vehicle based on input from a steering input. The vehicle may include a first drive wheel and a second drive wheel. The vehicle may include a steering position sensor configured to detect steering input including a position of the steering input and at least one of i) a rate of change of position of steering input and ii) steering position time. The vehicle may include at least one controller configured to process a signal from the steering position sensor and, in response to the processed signal, drive the first drive wheel and the second drive wheel, the first drive wheel being driven independent of the second drive wheel.

A dual path agricultural machine including a control system having a number of input sensors, status sensors, and output sensors, and a controller configured to operate the dual path machine in a stability control mode and a selective rear-steer engagement and actuation mode. In the stability control mode, the controller adjusts an actual drive output of the dual path machine according to data received from the input sensors and feedback received from the output sensors so as to reduce a difference between the actual drive output and a desired drive output. In selective rear-steer engagement and actuation mode, the controller engages rear-steer mechanisms with caster wheels of the dual path machine and actuates the caster wheels via the rear-steer mechanisms if a criterion is satisfied. The controller disengages the rear-steer mechanisms from the caster wheels or does not actuate the caster wheels if the criterion is not satisfied.

A steering system for controlling an agricultural machine having a pair of front and rear wheels includes a controller and a steer input sensor for detecting a change in an operator steer input corresponding to a steer command. The system includes a displacement input for communicating a motor displacement associated with an operating mode. A primary differential steering system includes a drive motor for operably controlling the pair of front wheels and a secondary steering system controls the pair of rear wheels. The controller determines if the motor displacement is being controlled according to a first motor displacement or a second motor displacement, and outputs a control signal to actuate first and second actuators as a function of the steer command. The control signal includes a rear steering gain that is a function of machine speed and either the first motor displacement or the second motor displacement.