Methods and systems are provided for controlling and diagnosing a mechanical vehicle component. In one example, a method may include determining a vehicle speed and a plurality of clutch position settings at a diagnostic controller, and identifying unauthorized conditions based on these determinations. Further, the diagnostic controller may trigger an active fault state of the mechanical vehicle component in order to avoid unauthorized conditions that may lead to unwanted or unanticipated changes in vehicle motion.

A traction control method and a traction control apparatus for a vehicle are provided. The traction control method includes: estimating driving torque for each wheel and a difference between left and right wheel rotation speeds; determining a situation, in which the difference between the left and right wheel rotation speeds exceeds a first set value, to be a split wheel spin situation; estimating a maximum coefficient of friction between a spinning wheel and a road surface in the split wheel spin situation and estimating a maximum driving torque, at which the road surface is acceptable, by the maximum coefficient of friction; and obtaining a difference between driving torque of the spinning wheel and the maximum driving torque to calculate a road surface limitation excess driving torque and determining entry into traction control when the road surface limitation excess driving torque exceeds a second set value.

A method for controlling a braking system of a motor vehicle that includes a plurality of wheels, at least one electric motor as a drive, a service brake and a vehicle dynamic control system. The wheels can be braked by a deceleration torque applied by the service brake and at least partially by a deceleration torque (M.sub.E) applied by the electric motor where slippage which arises as a result of braking and/or of intervention by the vehicle dynamic control system is regulated at least primarily through adjustment of the deceleration torque applied by the electric motor. When necessary, a drive torque is applied to regulate slippage or to cause a locked wheel to rotate by the electric motor.

A computer system including a processor device configured to adjust a torque applies to a first wheel to a vehicle is provided. The processor device is configured to estimate, a variation in rotational speed of a first drive shaft. The first drive shaft is driven by a second drive shaft by rotating a mechanical joint. The mechanical joint is drivingly connected to both the first drive shaft and the second drive shaft. The processor device is configured to, based on the variation in rotational speed of the first drive shaft and a current speed of the vehicle, estimate a target slip for the first wheel. The processor device is further configured to, based on the estimated target slip for the first wheel, adjust the torque applied to the first wheel.

A method for controlling motion of a heavy-duty vehicle, the method including: obtaining input data related to one or more parameters of a tire on the heavy-duty vehicle, determining at least part of the one or more tire parameters based on the input data, configuring a tire model, wherein the tire model defines a relationship between wheel slip and generated wheel force, wherein the tire model is parameterized by the one or more tire parameters, and controlling the motion of the heavy-duty vehicle based on the relationship between wheel slip and generated wheel force.

A desired change of a time derivative of dynamic torque (Tq.sub.fw), provided to an output shaft from an engine in a vehicle, from a current value to a new desired value is determined. A current rotational speed difference (??.sub.pres) is determined between a first end of the powertrain in a vehicle, which rotates with a first rotational speed (?.sub.1), and a second end of the powertrain, which rotates with a second rotational speed. The first rotational speed (?.sub.1) is then controlled on the basis of the desired value of the time derivative for the dynamic torque (Tq.sub.fw), a spring constant (k) related to a torsional compliance in the powertrain, and the determined current rotational speed difference {??.sub.pres). Through control of the first rotational speed, the current value for the time derivative for the dynamic torque is also indirectly controlled towards the desired value.

A control system for a driveline of a vehicle and method of operating the control system are provided. The system includes a base torque calculation module in communication with a plurality of vehicle controllers. The base torque calculation module determines and outputs a wheel torque command signal. A torque modulation module generates a periodic torque modulation signal based on the wheel torque command signal and a plurality of tire parameters. An adder module adds the periodic torque modulation signal to the wheel torque command signal and outputs a modulated wheel torque command signal to a wheel torque generator to linearize a tire characteristic of the plurality of tires of the vehicle. A slip and force determining module determines and outputs a plurality of slip estimates and estimated forces and a plurality of tire parameters to the torque modulation module, the plurality of vehicle controllers, and base torque calculation module.

A motor vehicle sets a front wheel average rotation speed that is an average rotation speed of left and right front wheels, based on a rotation speed of a first motor, and sets a rear wheel average rotation speed that is an average rotation speed of left and right rear wheels, based on a rotation speed of a second motor. When a difference between the front wheel average rotation speed and the rear wheel average rotation speed is larger than a first reference value, the motor vehicle sets a vehicle body speed, based on the lower between the front wheel average rotation speed and the rear wheel average rotation speed. The motor vehicle compares a difference between the vehicle body speed and the wheel speed of each wheel, with a second reference value and thereby determines whether the wheel idles.

A method for determining a state of a roadway of a vehicle. A first distance value of a measurement coordinate to a first tire characteristic curve associated with a first state of the roadway is ascertained. A second distance value of the measurement coordinate to a second tire characteristic curve associated with a second state of the roadway is ascertained. The measurement coordinate represents a measurement carried out using at least one vehicle sensor of a presently utilized traction between wheels of the vehicle and the roadway and a wheel slip of the wheels, while the first tire characteristic curve and the second tire characteristic curve are based on a model function for the modeled representation of the traction as a function of the wheel slip. An output signal representing the state of the roadway is output using the first distance value and the second distance value.

A method of controlling driving force of a vehicle includes estimating a first maximum road surface frictional coefficient based on a driving stiffness defined by a micro slip ratio and driving force of drive wheels, in a first driving state where the vehicle travels straight at a constant acceleration, estimating a second maximum road surface frictional coefficient based on a steering reaction force detected by an electric power steering device, in a second driving state different from the first state and where the vehicle is steered, estimating a third maximum road surface frictional coefficient to be a given value in a third driving state different from the first and second states and where an outdoor air temperature is above a determination temperature, and controlling the driving force to settle within a friction circle defined by each of the highest frictional coefficients and a ground contact load of the drive wheels.