A method for determining unstable behavior of a trailer of a vehicle combination, the vehicle combination having N members, one of the members being a tractor vehicle and at least one further member being the trailer, the unstable behavior of the trailer being determined depending on a driving-dynamics actual characteristic variable of the tractor vehicle, includes: determining at least one driving-dynamics actual characteristic variable of the trailer, the at least one driving-dynamics actual characteristic variable characterizing a current driving-dynamics state of the trailer and following from a measurement by at least one sensor in the trailer; and determining at least one driving-dynamics target characteristic variable of the trailer, the at least one driving-dynamics target characteristic variable following from the at least one driving-dynamics actual characteristic variable of the tractor vehicle by using a kinematic model depending on geometric characteristic variables of the vehicle combination.

A system for controlling a vehicle by jointly estimating a state of a vehicle and a function of a tire friction of a vehicle traveling on a road uses a particle filter maintaining a set of particles. Each particle includes an estimation of a state of the vehicle, an estimation of probability density function (pdf) of the tire friction function, and a weight indicative of a probability of the particle. The system executes the particle filter to update the particles based on a motion model and a measurement model of the vehicle, control commands moving the vehicle and measurements of the state where the vehicle moved according to the control commands. A control command is generated based on the motion of the vehicle, the weighted combinations of the state of the vehicle and the pdf of the tire friction function weighted according corresponding weights of the particles.

A vehicle sideslip estimation system includes sensors mounted on a vehicle and a kinematic model receiving signals from the sensors to estimate a lateral velocity of the vehicle. A compensated acceleration calculator calculates a compensated lateral acceleration as a measure of conditions that result in a deviation of a measured lateral acceleration. A lateral acceleration calculator determines, based on the compensated lateral acceleration and the measured lateral acceleration, if a lateral acceleration error is larger than a predefined threshold. A filter corrects the estimated lateral velocity of the vehicle when the lateral acceleration error is larger than the predefined threshold. A velocity output register registers the estimated lateral velocity of the vehicle when the lateral acceleration error is smaller than the predefined threshold, and a sideslip calculator calculates a sideslip angle of the vehicle in real time from the registered lateral velocity of the vehicle and a vehicle longitudinal velocity.

Methods and systems for autonomously steering a moving vehicle are disclosed. A processor determines a longitudinal velocity, a longitudinal acceleration, a lateral acceleration, and a yaw rate of the vehicle. The processor estimates, based on the longitudinal velocity, lateral acceleration, and yaw rate of the vehicle, a change in lateral velocity over time. The processor estimates, based on the change in the lateral velocity over time, the yaw rate, a distance between the front axle of the vehicle and a center of gravity of the vehicle, and a distance between the rear axle of the vehicle and the center of gravity of the vehicle, a lateral front velocity of the vehicle and a lateral rear velocity of the vehicle. Using calculations, a state estimation model for the vehicle is updated by the processor using a lateral acceleration bias. The updated state estimation model is used to autonomously steer the vehicle.

The present invention relates to a wheel controller (108) for a vehicle (100), comprising a wheel slip calculation module (212) arranged to calculate a longitudinal wheel slip value for a wheel slip between a surface of the wheel (102) and a road surface thereof; a wheel force estimation module (214) arranged to estimate a longitudinal wheel force value for a wheel force between the surface of the wheel (102) and the road surface; a tire model generator (216) arranged to receive longitudinal wheel slip values from the wheel slip calculation module (212) and longitudinal wheel force values from the wheel force estimation module (214); said tire model generator (216) being configured to generate a model (300, 400) representing a relationship between the calculated longitudinal wheel slip and the estimated longitudinal wheel force by using at least three longitudinal wheel force values and three corresponding longitudinal wheel slip values; and a vehicle wheel capability module (218) arranged in communication with the tire model generator (216), said vehicle wheel capability module (218) being configured to determine an absolute maximum wheel friction level between the surface of the wheel (102) and the road surface thereof by means of acquiring, for a calculated wheel slip value, a longitudinal wheel force value from the model (300, 400) of the tire model generator.

A system and method for speed/traction/slip control influences a driving engine torque of the vehicle. The method includes: calculating an idealized nominal engine torque from a linear control law applied to the speed/slip error; calculating an idealized setpoint for the speed/slip by applying a reference model to the idealized nominal engine torque; calculating a linearizing feedback with properties of compensating the nonlinearities in the road surface contact, compensating the inertia in the powertrain, and damping the powertrain; using for feedback the engine rotational speed, numerically determined derivation of engine speed, average speed of the driven axis, numerically determined derivative of the rotational speed of the driven axis, actual engine torque, and applying the driving engine torque to the engine vehicle to influence the traction and stability of the vehicle.

A method for determining changes in the longitudinal-dynamic behavior is disclosed, in particular of an undercarriage, of a railway vehicle for identifying a current driving condition of the railway vehicle, wherein variables, which cannot be measured and which characterize the longitudinal-dynamic behavior, are reconstructed and evaluated via a system model of the railway vehicle by means of a cybernetic observer from a known or metrologically determined input signal and at least one measuring signal of the observed railway vehicle as an observed real reference system. The at least one measuring signal of the observed railway vehicle and a corresponding reconstructed measuring signal of the system model are compared and the deviation determined by comparison is recursively tracked with a regulator so that the determined deviation is minimized.

A control system for a vehicle includes a plurality of vehicle actuators that are operable to affect actual chassis-level accelerations, a vehicle intelligence unit that determines a motion plan, a vehicle motion control unit that determines a chassis-level motion request based on the motion plan, and a chassis control unit that determines actuator commands for the plurality of vehicle actuators based on the chassis-level motion request and actuator identity information that describes presently available actuators from the plurality of vehicle actuators.

A braking force control device includes a target acceleration calculation unit that calculates a first target acceleration based on an acquired operation amount of an accelerator pedal, a powertrain capability acquisition unit that acquires a braking force that is generable by a powertrain, and an instruction unit that instructs generation of braking forces in the powertrain and a brake. The instruction unit is configured to, when a first braking force for achieving the first target acceleration is equal to or less than the braking force that is generable by the powertrain, instruct a controller of the powertrain to generate the first braking force, and when the first braking force is larger than the braking force that is generable by the powertrain, instruct the controller of the powertrain to generate the braking force that is generable by the powertrain.

A method for determining changes in the longitudinal-dynamic behavior is disclosed, in particular of an undercarriage, of a railway vehicle for identifying a current driving condition of the railway vehicle, wherein variables, which cannot be measured and which characterize the longitudinal-dynamic behavior, are reconstructed and evaluated via a system model of the railway vehicle by means of a cybernetic observer from a known or metrologically determined input signal and at least one measuring signal of the observed railway vehicle as an observed real reference system. The at least one measuring signal of the observed railway vehicle and a corresponding reconstructed measuring signal of the system model are compared and the deviation determined by comparison is recursively tracked with a regulator so that the determined deviation is minimized.