Methods and systems for operating axles of a vehicle are provided. In one example, a propulsion source of a first axle is operated in a torque control mode at a first torque and a propulsion source of a second axle is operated in a torque control mode at a second torque. Torque of the propulsion sources may be adjusted as a function of steering angle.

A steering apparatus includes: a steering mechanism including a turning shaft; a motor configured to give a drive force to the steering mechanism; and a controller configured to control the motor based on a command value. The controller includes a first computation circuit, a second computation circuit and a third computation circuit. The first computation circuit is configured to compute a shaft force that acts on the turning shaft. The second computation circuit is configured to compute a value indicating the degree of intervention in a steering control by a host controller, such that the value gradually changes with respect to time. The third computation circuit is configured to compute a final shaft force, by reflecting the value indicating the degree of the intervention, in the shaft force.

The vehicle control device of the present invention acquires characteristics of a road condition in front of a traveling vehicle based on external information; acquires vehicle behavior control variables for controlling the behavior of the vehicle based on estimated state variables of the vehicle that are obtained based on the characteristics, and control variables concerning speed of the vehicle based on the external information; acquires trajectory tracking control variables for causing the vehicle to track the target trajectory based on the target trajectory on which the vehicle travels that are obtained based on the characteristics and the estimated state variables; and outputs the control commands for controlling the suspension device, steering device, and braking and driving device based on the vehicle behavior control variables and the trajectory tracking control variables. This improves travel stability of the vehicle on a road surface on which an irregularity such as ruts exists.

Terrain characteristics of an off-road area are determined based on a map. The terrain characteristics include a terrain type, a terrain grade, and a presence or an absence of an obstacle. Vehicle characteristics are determined including a ground clearance and a breakover angle. Based on a user level, vehicle parameters for the off-road area are determined based on the terrain characteristics, the vehicle characteristics, and the user input. The vehicle parameters include a speed and a transmission gear. The vehicle parameters for the off-road area are output.

A technology of mechanically classifying a switching operation between a traveling mode and a special moving mode is provided to prevent a mode switching misoperation. A traveling mode switching mechanism of a four-wheel independent steering type vehicle includes a shift gate which is disposed by forming a moving path of a shift lever, and grouping a traveling mode and a special moving mode. Additionally, a mode switching differentiation devices differentiates a mode switching operation of a driver by configuring so that an operation of the shift lever switched between the traveling mode and the special moving mode is physically different from an operation of the shift lever switched between the traveling modes or between the special moving modes.

A vehicle control system includes a steering operation element configured to receive a steering operation of a vehicle by a driver, a grip detector configured to detect a gripping state of the steering operation element by the driver of the vehicle, a traveling controller configured to perform traveling control related to steering and acceleration or deceleration of the vehicle, and a determiner configured to determine on the presence or absence of execution of the traveling control or the degree of execution of the traveling control based on the gripping state.

A motor controlling ECU 202 includes an automatic steering controller 42 that sets an automatic steering control amount, an assist controller 41 that sets an assist control amount, an integrated control amount calculating portion 43 that calculates an integrated control amount by adding the automatic steering control amount and the assist control amount, and an actual automatic steering angle calculating portion 46 that calculates, based on at least one of either of a steering torque and the assist control amount, an actual automatic steering angle that is a steering angle due to automatic steering control and included in an actual steering angle. The automatic steering controller 42 uses a target automatic steering angle and the actual automatic steering angle to set the automatic steering control amount.

An apparatus (104) and a method (800) for controlling steering of rear wheels (103) of a vehicle (100) are disclosed. The apparatus (104) comprises a control means (105) configured to receive a first signal indicative of a front wheel steering angle and a second signal indicative of a selected mode selected from at least a first mode and a second mode. The control means is also configured to determine a proposed rear wheel steering angle in dependence on the first signal and the second signal and to provide an output signal configured to cause steering of rear wheels (103) at the proposed rear wheel steering angle.

A steering system for controlling a direction of travel of a work machine includes a steering device controllable by an operator of the work machine. The steering device is coupled to an axle of the work machine for controlling an angular orientation of the wheels. A brake is coupled to the steering device and is controllably applied to apply a first amount of resistance to the steering device. A motor is coupled to the steering device and is controllably activated to apply a second amount of resistance to the steering device. A controller controls the steering system of the work machine in at least a first operating mode and a second operating mode. In the first operating mode, the controller controls the brake between an applied position and an unapplied position, whereas in the second operating mode, the controller controls the motor between an active position and a de-activated position.

A work vehicle including an articulated vehicle chassis having a front frame portion and a rear frame portion pivotally coupled together at a generally vertical pivot axis. The front frame portion carries a front axle and the rear frame portion carries a rear axle. A steering system includes at least one steering cylinder connected between the front frame portion and the rear frame portion. A power plant provides motive power to the work vehicle, and a transmission receives power from the power plant and provides power to the front axle and rear axle. The work vehicle further includes a secondary clutch interconnected between the transmission and the rear axle. The steering system is configured to disengage the secondary clutch to provide reactive steering, whereby the front frame portion tows the rear frame portion. The rear frame portion freely articulates relative to the front frame portion.