Method for operating a motor vehicle or vehicle combination, control device, motor vehicle or vehicle combination

Abstract

The invention relates to a method for operating a motor vehicle (1) or vehicle combination (2), wherein actual state variables characterizing an actual vehicle state are determined, which for at least one, in particular each, of the wheels (4) of the motor vehicle (1) or vehicle combination (2) each comprise at least one component of an actual force vector for forces acting on the respective wheel (4), wherein desired state variables characterizing a desired vehicle state are specified, which for at least one, in particular each, of the wheels (4) of the motor vehicle (1) or vehicle combination (2) each comprise at least one component of a desired force vector for forces to be generated on the respective wheel (4), wherein a deviation of the actual state variables from the desired state variables is determined in each case,wherein, depending on a respective deviation, a quality functional describing a control quality of a control of actuators (6-9) assigned to the wheel (4) is determined, wherein the actuators (6-9) have at least a first actuator (6) of a spring-damper system and a second actuator (7-9) of a steering system, braking system and / or drive system of the motor vehicle (1) or vehicle combination (2), wherein by minimizing the quality functional, target values ​​for at least one manipulated variable of each of the actuators (6-9) are determined, and wherein the respective actuators (6-9) are controlled depending on the determined target values.

Description

[0001] The invention relates to a method for operating a motor vehicle or vehicle combination, a control device specially designed to carry out such a method, and a motor vehicle or vehicle combination with such a control device. State of the art

[0002] The transfer of forces and torques via the tires to the road surface plays a crucial role in the dynamics of a motor vehicle or vehicle combination. The maximum transferable force at each wheel depends, among other things, on the condition of the road surface and the respective normal force. The normal forces contain static and dynamic components and are determined, for example, by the weight and load distribution in the vehicle, trailer operation, or the current driving situation, such as cornering, road gradient, and / or road surface.

[0003] The forces acting on the wheel in the vertical, circumferential, and lateral directions are interrelated. Actuators such as the steering, braking, and drive systems, as well as wheel damper systems, directly influence individual tire forces and thus change the overall force ratios at the wheel through the coupling of the forces at the wheel and the reaction of the chassis and vehicle body. Based on these interrelationships, chassis control systems such as ESP, superimposed or active steering systems, and by-wire steering systems on the front and / or rear axle can influence the agility and stability of the vehicle right up to the physical limits.

[0004] Vibration damping is required between the wheel or vehicle axle and the vehicle body because typical road excitation is broadband, meaning that the natural frequencies for the body ("sprung mass") and the wheel mass ("unsprung mass") must be damped. A compromise must be found between sufficient damping of each wheel and the respective axle, which ensures roadholding of the wheel and thus driving safety, and the introduction of energy into the body in a way that is perceived as comfortable by the vehicle occupants. Shocks acting on the vehicle from the ground are absorbed by the suspension in such a way that the sprung and unsprung masses do not come into contact. Vibration dampers arranged in parallel usually ensure that the vibration between the wheel or axle and the body caused by a relaxation of the suspension is specifically reduced.

[0005] The dampers are often hydraulically and mechanically designed. The relationship between force and travel, which is then determined by the design, can be influenced within limits using special measures, such as stroke-dependent damping or frequency-selective damping. Semi-active or active suspensions are used to flexibly adjust ride comfort and safety to key influencing factors such as load distribution, driving conditions, or road profiles. Semi-active automatic damping force controls (e.g., Pneumatic Damping Control PDC, Continuous Damping Control CDC) can limit or delay body movements and wheel load fluctuations, but can only be eliminated promptly to a certain extent. This is only possible with fully active systems (Active Roll Stabilization ARS and Active Body Control ABC).

[0006] When designing these systems, a compromise must be found between dynamics, bandwidth, weight, cost, and energy consumption. In addition to pneumatic, hydraulic, and combined designs, electric dampers are also available. In recent years, systems with rheological fluids have also been used.

[0007] The active chassis systems known to date are typically effective within a limited dynamic range, require a lot of installation space, and are expensive, which limits their use primarily to large and expensive vehicles. It is foreseeable that demands on ride comfort will increase in the future, particularly due to the increased market penetration of mass-produced electric vehicles, and that active chassis systems will therefore also be implemented in additional vehicle classes. The less people in the vehicle have to concentrate on performing driving tasks (such as following a lane, maintaining a safe distance, etc.), the more sensitively they perceive the vehicle's movement, and their sense of comfort will be impaired by disturbances to what they perceive as a natural course.

[0008] It is generally known to coordinate the control of such active chassis systems with other control systems, for example, for a braking system and / or a steering system, in order to achieve harmonious vehicle movement in all driving conditions (networked control systems). In particular, all chassis actuators are controlled from a central controller (central control system with multi-actuator control). With the help of new technologies, in particular the systems described above with rheological fluids in the form of magnetorheological fluid actuators, as described, for example, in the publications US 2012 0 085 613 A1, US 10 752 139 B2, US 10 746 235 B2, or WO 2021 092 683 A1, active chassis actuators are conceivable that have significantly improved properties in terms of dynamics, bandwidth, weight, cost, and energy consumption. Disclosure of the invention

[0009] The method according to the invention with the features of claim 1 is characterized in that actual state variables characterizing an actual vehicle state are determined, which for at least one, in particular each, of the wheels of the motor vehicle or vehicle combination each comprise at least one component of an actual force vector for forces acting on the respective wheel; that desired state variables characterizing a desired vehicle state are specified, which for at least one, in particular each, of the wheels of the motor vehicle or vehicle combination each comprise at least one component of a desired force vector for forces to be generated on the respective wheel; that a deviation of the actual state variables from the desired state variables is determined; that, depending on a respective deviation, a quality functional describing a control quality of a control of actuators assigned to the wheel is determined;that the actuators comprise at least a first actuator of a spring-damper system and a second actuator of a steering system, braking system, and / or drive system of the motor vehicle or vehicle combination; that by minimizing the quality function, target values ​​are determined for at least one manipulated variable of each of the actuators, and that the respective actuators are controlled depending on the determined target values. A vehicle combination is understood here to be a motor vehicle as a towing vehicle with at least one, at least single-axle, trailer coupled thereto. The spring-damper system, steering system, braking system, and / or drive system can be provided on the towing vehicle and / or on the trailer; in particular, both the towing vehicle and the trailer each comprise at least one system with at least one corresponding actuator. The core idea of ​​the invention is, in this respect,to actively influence the forces acting on the wheels of the motor vehicle or vehicle combination by controlling appropriate actuators of the systems in a skillfully coordinated manner. This is generally known for spring-damper systems alone, for example, by semi-actively changing damper characteristics and / or actively raising or lowering the motor vehicle. The present invention therefore also makes particular use of the properties of the novel systems mentioned above, in particular magnetorheological fluid actuators, for optimizing the driving dynamics, safety, and comfort of a vehicle. The method according to the invention provides that at least one further actuator of at least one further system is also controlled by changing corresponding control variables. This advantageously ensuresthat the wheel forces required to achieve the target vehicle state are set with particular precision by means of the corresponding actuators, and thus driving dynamics and driving safety are advantageously further improved. The object of the invention is, depending on the driving situation, to influence the forces on at least one, in particular all, tires of the vehicle within the scope of the current possibilities by means of a coordinated control of several, in particular all, available chassis actuators in the form of the corresponding actuators in such a way that a desired vehicle behavior, namely the target vehicle state, is optimally achieved. This is achieved according to the invention by minimizing a quality function, wherein preferably various variables such as dynamic behavior of the vehicle, driving comfort for the occupants and / or current energy consumption are taken into account in the quality function. This ensures that, both in everyday driving situations,For example, when driving on roads with potholes, rough surfaces, or bumps, as well as at the physical limits, such as when cornering too quickly or performing evasive maneuvers, the vehicle's driving dynamics, safety, comfort, and / or energy consumption are further improved compared to conventional chassis and vehicle dynamics control systems within the physical limits. In conjunction with higher levels of automation in driver assistance systems, the coordinated control of the corresponding chassis actuators increases the achievable level of safety, for example, during an automatic emergency lane change due to the detection of an obstacle such as a "person in the lane," "lost cargo," and / or an "oncoming vehicle." Wheel forces are particularly preferably influenced three-dimensionally, i.e., in the x, y, and z directions, or transversely.longitudinally and vertically with respect to the wheel. Preferably, target values ​​for manipulated variables of a plurality of actuators assigned to the wheel are determined, and the actuators are controlled accordingly. For example, in addition to the actuators of the spring-damper system, actuators of the steering system, braking system, and drive system are controlled as needed. In particular, all actuators suitable for influencing the wheel forces are controlled in this way. Preferably, the target values ​​of the manipulated variables are determined depending on a current actual driving situation and / or a target driving situation to be achieved. In particular, the established quality function is then minimized for the actual driving situation. For example, the quality function is used to validate at least one of the force vectors. In this case, a quality function is a quantity that is fundamentally known from control engineering and is used according to the invention toto generate a concerted control strategy for at least two, in particular a plurality of, actuators assigned to the respective wheel. By taking into account the components of the force vectors, the quality functional combines various actual state variables describing the current vehicle condition, which, as described above, were measured directly or estimated using appropriate models.

[0010] According to a preferred development of the invention, the component of the force vector(s) comprises at least a vertical wheel contact force of the wheel, a longitudinal force acting on the wheel, and / or a transverse force acting on the wheel. By taking corresponding forces into account, it is advantageously ensured that the respective force vector has corresponding force components in one or more dimensions; when all three of these forces are taken into account, the respective force vector represents the forces accordingly in three dimensions. For example, wheel-specific wheel contact forces are determined, in particular estimated or measured using suitable sensors. In particular, longitudinal forces are determined using sensors assigned to the drive system or measured directly.

[0011] Particularly preferably, the actual vehicle condition and the deviation are continuously determined, resulting in a temporal progression of the deviation, which is integrated into the quality functional. This results in the advantage that the quality functional exhibits a temporal dependency and, to this extent, also a temporal progression of the variables included in the actual vehicle condition.

[0012] According to a preferred development of the invention, the target vehicle state and / or the quality functional are specified or determined depending on at least one predetermined vehicle characteristic. Taking the vehicle characteristic into account advantageously ensures that the subsequent control of the actuators is optimized accordingly.

[0013] Particularly preferably, it is provided that driving safety, driving agility, driving comfort, and / or energy consumption are specified as vehicle characteristics. Taking such vehicle characteristics into account results in the advantage that the subsequent control of the actuators is optimized with particular precision.

[0014] According to a preferred development of the invention, a value and a weighting factor are assigned to a plurality of vehicle characteristics and taken into account in the quality function. This advantageously ensures that the quality function comprises a dynamically weighted sum of various desired vehicle characteristics.

[0015] Particularly preferably, the actual vehicle state and / or the desired vehicle state are determined, in particular calculated or model-based estimated, as a function of at least one input variable characterizing a vehicle movement. This results in the advantage that the vehicle states can be determined particularly easily and precisely.

[0016] According to a preferred development of the invention, the input variables recorded are steering angle, wheel speed, yaw rate, pitch rate, roll rate, acceleration, normal force, suspension travel, and / or vehicle position. Taking such input variables into account advantageously ensures that the current behavior of the motor vehicle or vehicle combination is mapped particularly accurately.

[0017] The control device, particularly designed as a computer device, with the features of claim 9 is characterized in that it is specifically designed to carry out the method according to the invention. This results in the aforementioned advantages.

[0018] The motor vehicle or vehicle combination with the features of claim 10 has a plurality of wheels and a plurality of actuators assigned to at least one of the wheels, wherein the actuators comprise at least a first actuator of a spring-damper system and a second actuator of a steering system, braking system, and / or drive system of the motor vehicle or vehicle combination. It is characterized by the control device according to the invention. This also results in the aforementioned advantages.

[0019] Further preferred features and combinations of features emerge from the above description and from the claims. The invention is explained in more detail below with reference to the drawings. Fig. 1 an advantageous motor vehicle or vehicle combination, and Fig. 2 a method for operating the motor vehicle or vehicle combination.

[0020] Fig. 1 shows, merely schematically and structurally, components of an advantageous motor vehicle 1 or a vehicle combination 2, consisting of a tractor, in this case in the form of the motor vehicle 1, and at least one, at least single-axle, trailer coupled thereto. The motor vehicle 1 or the vehicle combination 2 each have a chassis 3 with a plurality of wheels 4. In this case, one or more actuator arrangements 5 are assigned to the chassis 3 or to each of the wheels 4.

[0021] The actuator arrangement 5 comprises a plurality of actuators, in this case at least one first actuator 6 of a spring-damper system, and at least one second actuator, in this case selected from a second actuator 7 of a steering system, a second actuator 8 of a braking system (for example a wheel braking device) and a second actuator 9 of a drive system (for example an electric drive motor) of the motor vehicle 1 or the vehicle combination 2.

[0022] In other words, as a minimum requirement, at least one of the wheels 4 is assigned a corresponding first actuator 6 and at least one of the second actuators 7 to 9. In particular, all of the aforementioned actuators 6 to 9 are provided at least once for at least one of the wheels 4, in particular, all of the actuators 6 to 9 are provided for at least two of the wheels 4 of the same axle, or even for each of the wheels 4. Any combinations are conceivable here.

[0023] In a motor vehicle 1 with front-wheel drive, for example, all four actuators 6 to 9 are provided at least once for each of the two wheels 4 of the front axle, assuming that the spring-damper system, steering system, braking system, and drive system are assigned to the wheels 4 of the front axle, as is usual. Accordingly, in this example, only a first actuator 6 of the spring-damper system and a second actuator 8 of the braking system are provided for the wheels 4 of the rear axle of the motor vehicle 1, because these are assigned neither drive nor steering. Analogously, in a trailer of the vehicle combination 2, for example, a first actuator 6 and a second actuator 8 are provided for each of the wheels 4 of an axle, provided that the corresponding wheels have neither drive nor steering.

[0024] In any case, the corresponding actuators 6 to 9 of the actuator arrangement 5 are designed as chassis actuators or chassis adjusters to directly influence the chassis 3 and / or the vehicle body by appropriate control with regard to the forces acting on the respective wheel 4.

[0025] For the corresponding control, a control device 10 is provided in the present case, which is communicatively connected to the actuator assembly 5, as indicated by an arrow extending from the control device 10 to the actuator assembly 5. The control device 10 is designed in particular as a central control device or part of at least one of the described systems, i.e., spring-damper system, steering system, braking system, and / or drive system.

[0026] Each of the actuators 6 to 9 has special actuator properties, for example, with regard to manipulated variable limitation, dynamics, energy consumption, and / or operating principle, which are known to the control device 10 as input variable E4, as indicated by a corresponding arrow extending from the actuator arrangement 5 to the control device 10. The control device 10 is also communicatively connected to another control device 11, as indicated by a corresponding arrow.

[0027] The control device 11 is designed to specify a desired behavior for the motor vehicle 1 or the vehicle combination 2 as input variable E3 and / or to transmit it to the control device 10. For example, the control device 11 is part of a vehicle assistance system and / or is designed to detect and / or evaluate a driver request regarding the desired behavior.

[0028] The chassis 3 and wheels 4 are further assigned a sensor arrangement 12 which is designed to measure input variables characterising a vehicle movement on the chassis 3 and / or wheels 4, for example selected from a group of steering angle, wheel speed, yaw rate, pitch rate, roll rate, acceleration, normal force, suspension travel and / or vehicle position.

[0029] The corresponding input variables E1 and E2 are, in particular, as indicated by a corresponding arrow, forwarded directly to the control device 10 as first input variables E1 in the form of measured variables E1, and / or are first evaluated by a computing unit 13 assigned to the sensor arrangement 12 and / or converted into corresponding second input variables E2 in the form of estimated variables E2 by means of a driving state estimation and only then forwarded to the control device 10. The computing unit 13 can be arranged remotely from the control device 10 or, alternatively, be part of the control device 10. In particular, the computing unit 13 is part of a vehicle dynamics control system.

[0030] With the aforementioned variables or values ​​that are made available to the control device 10, i.e. the actuator properties, the desired behavior, the measured variables and / or the estimated variables, the control device 10 is then able to control the actuator arrangement 5 with the individual actuators 6 to 9 in such a way that the desired behavior for the motor vehicle 1 or the vehicle combination 2 is achieved in the best possible way, preferably by carrying out a situation-dependent desired value calculation for the tire forces to be generated at the respective wheels 4.

[0031] In the following, with reference to Fig. 2 describes an advantageous method for operating the motor vehicle 1 or vehicle combination 2. For this purpose, the Fig. 2 illustrates the method using a flowchart. In particular, the method ensures that the various chassis actuators are controlled in a manner tailored to the current driving situation, such that the wheel forces contribute to optimal vehicle behavior in terms of driving dynamics, safety, and / or comfort. The method is preferably implemented by means of the control device 10 as part of the aforementioned situation-dependent setpoint calculation.

[0032] Compared to existing implementations, the method leads to an improved distribution of the drive, braking, and wheel steering torques, as well as the control components of the vertical actuating forces, depending on the configuration of the actuators acting on the wheels, such as the number, arrangement, and characteristics of the drive, braking, steering, and chassis actuators. For example, the determination of the vehicle reference speed—particularly in all-wheel drive vehicles—is supported by reducing the risk of "roping up" or "roping down" (the quality of the determined vehicle speed) due to insufficient friction potential. This has a positive effect, particularly on the braking distance and / or traction.

[0033] In a step S1, the method begins by evaluating the current driving situation. For this purpose, actual state variables characterizing an actual vehicle state are first determined, which, for at least one, in particular each, of the wheels 4 of the motor vehicle 1 or vehicle combination 2, each comprise at least one component of an actual force vector for forces acting on the respective wheel 4.

[0034] Furthermore, target state variables characterizing a target vehicle state are specified, which for at least one, in particular each, of the wheels 4 of the motor vehicle 1 or vehicle combination 2 each comprise at least one component of a target force vector for forces to be generated at the respective wheel 4, and a deviation of the actual state variables from the target state variables is determined. The component(s) of the force vector(s) comprise, in particular, at least one vertical wheel contact force of the wheel 4, a longitudinal force acting on the wheel 4, and / or a transverse force acting on the wheel 4.

[0035] In the present case, the actual vehicle state and / or the desired vehicle state, in particular the respective component of the actual force vectors and / or the desired force vectors, are determined, in particular calculated or estimated based on a model for vehicle behavior, depending on at least one input variable characterizing a vehicle movement. As input variables, in particular, the steering angle, wheel speed, yaw rate, pitch rate, roll rate, acceleration, normal force, spring deflection and / or vehicle position are recorded. The input variables in the present case are at least one, in particular all of the Fig. 1 described measured quantities E1 and / or estimated quantities E2.

[0036] The vehicle behavior is preferably abstracted in such a way that all aspects relevant to the control objective (optimal adjustment of the wheel forces) are adequately described in a model. This means, in particular, that for the determination of the situation-dependent target values, essential variables such as the aforementioned individual measured variables E1 with reference to the vehicle movement as well as corresponding estimated variables E2, which are determined, for example, on the basis of measured variables E1 in a model-based manner, as is particularly implemented in the context of the driving state estimation of a vehicle dynamics control system, are sufficiently accurately represented in their mutual dynamic linkage in a quarter-vehicle, half-vehicle, or full-vehicle model, as in the Fig. 1 are described.

[0037] This model is preferably presented in the form of a state space representation x˙_=f(x_(t),u(t),t);x_(t0)=x_0 where x(t) is a vector of state variables, in particular with the state variables sideslip angle x1 = β, yaw rate x2 = ̇φ̇ and roll velocity x3 = ω̇, and u(t) is a vector of input variables, such as the actuator control variables with steering wheel angle u1 = δ and / or damper forces u i = F i , i = 1, 2, 3, 4, at the individual wheels. The initial state (or actual state) of the vehicle is denoted by x(t0) = x0.

[0038] In particular, the state space representation is supplemented by a term with known road irregularities w under the wheels, as is known, for example, from Göhrle, C.: “Methods and implementation of a predictive chassis control for active and semi-active suspension systems.” Shaker Verlag, Aachen 2014.

[0039] Preferably, the target vehicle state is specified depending on at least one predefined vehicle characteristic. In particular, driving safety, driving agility, driving comfort, and / or energy consumption are specified as vehicle characteristics.

[0040] Further input variables, at least for determining the target vehicle state, in particular the target force vector, are in particular the ones also mentioned above with reference to the Fig. 1 already described input variables E3 and / or E4, concerning the target behavior or the actuator properties.

[0041] In particular, target values ​​for the forces at each wheel 4 of the vehicle, preferably in the longitudinal, transverse, and vertical directions, are generated using numerical methods, taking into account the properties of the actuators as control characteristics in the form of manipulated variable limitation, dynamics, energy consumption, and / or operating principle. This advantageously exploits the different dynamics of the existing actuators and thus the time delays in their effect on the wheel forces.

[0042] In an optional step S2, a quality of the detection of the vehicle position carried out using the measured variables E1 is determined in the form of a measurement quality, in particular taking into account the measurement accuracy in determining the respective measured variables, which depends, for example, on the sensors used and their installation location.

[0043] For measured contact forces, for example, using known measurement methods such as strain gauges or piezo elements, the contact force is determined dynamically, particularly for each wheel. If the contact forces cannot be measured directly due to design constraints, but information on vertical accelerations and / or compression travel of individual wheel suspensions is available (as measured variables E1), the respective wheel contact force is estimated, particularly using a model (as estimated variable E2), with uncertainties regarding the mass and load distribution of the vehicle / vehicle combination. Such differences in the accuracy of the driving condition detection are reflected in the measurement quality.

[0044] In a subsequent step S3, into which the results of steps S1 (deviation) and S2 (measurement quality) are incorporated, a quality functional describing a control quality of a control of the actuators 6 to 9 assigned to wheel 4 is determined as a function of a respective deviation, and a coordinated control of the various actuators is derived therefrom.

[0045] The above-described actual vehicle state x0 is to be transformed into a target state x(t e ) = x eThis is formulated as a dynamic optimization problem with a quality functional to be minimized: J=h(x_(te),te)+∫t0tef(x_(t),u_(t),t)dt→min

[0046] The quality function is thus generated by means of a model-based determination of the driving state and evaluation of the driving situation, as described above, based on available sensor information and, for example, estimated variables available in vehicle dynamics control systems, as well as the desired vehicle behavior. This quality function explicitly considers the measurement quality of the input variables. This allows measurement inaccuracies (e.g., sensor installation position, selected measurement principle) to be taken into account to ensure sufficient accuracy in determining the force at wheel 4.

[0047] Preferably, the actual vehicle condition and the deviation are continuously determined, resulting in a temporal progression of the deviation, which is incorporated into the quality function. Preferably, the quality function is determined as a function of at least one predetermined vehicle characteristic, as described above. Particularly preferably, a value and a weighting factor are assigned to a plurality of vehicle characteristics and taken into account in the quality function.

[0048] The performance function is then calculated based on the current driving situation in such a way that the currently relevant characteristics, such as driving safety (for example, with regard to lane keeping, but also at the physical limits), driving agility, driving comfort, and / or energy consumption, are appropriately weighted, thus achieving the best possible behavior at the current time. This is referred to as the evaluation of the driving situation.

[0049] The quality function described above is therefore composed of summands for the individual properties, which are determined primarily by the deviation between the target value and the actual value of the respective property and are multiplied by a respective weighting factor. The respective weighting factors are determined by the driving situation, with driving safety generally having the highest priority. The driver can preferably influence the weighting (for example, via the driving mode). The individual properties are then weighted adaptively.

[0050] For example, there are driving situations in which driving safety is not compromised, and thus the emphasis can be placed on driving comfort and energy efficiency, taking the selected driving mode into account. On the other hand, in situations where driving dynamics are critical, priority is generally given to driving safety (except in special driving modes designed for highly trained drivers), since driving comfort and energy consumption play a very subordinate role in these situations.

[0051] In a step S4 as a sub-step within step S3, target values ​​for at least one manipulated variable of at least the first actuator 6 and one of the second actuators 7 to 9, in particular each of the actuators 6 to 9, are determined by minimizing the quality functional. The quality functional is minimized under the constraints of the model described above for the motor vehicle 1 or the vehicle combination 2 with the corresponding input variables.

[0052] The quality function is then minimized, particularly in real time, under the constraints of the state-space model described above, using numerical methods. While the relationships between the individual wheel forces are represented in the state-space model, the properties of the available actuators are preferably taken into account in the quality function, so that the resulting manipulated variables for the individual actuators 6 to 9 can actually be implemented.

[0053] In a final step S5, which is a substep within step S3, the respective actuators 6 to 9 are controlled depending on the determined target values. The corresponding target values ​​are distributed among the actuators so that the individual target values ​​are optimally adjusted, thus resulting in the desired vehicle behavior. This concludes the process.

[0054] The method according to the invention makes it possible to implement various functions during stable, free-rolling driving. For example, specific load distributions are detected taking into account the gradient information in the vehicle, and the horizontal alignment of the vehicle body is adjusted using the active chassis actuators to optimize ride comfort.

[0055] Likewise, lane keeping on a sideways inclined road or in crosswinds (e.g. gusts of wind on bridges, after overtaking a truck) is supported in the interests of safety by a suitable combination of, for example, steering, chassis and drive torque intervention (if wheel-individual drive torque distribution is available) and in conjunction with lane-setting driver assistance functions.

[0056] It is also possible, for example, to control individual affected wheels when road irregularities are detected (e.g., through image processing or map-based information systems) in such a way that ride comfort and safety are optimized. Furthermore, it is possible, for example, to use active chassis actuators with energy recovery capability in such a way that ride comfort and energy balance are optimized.

[0057] Finally, the method according to the invention makes it possible, when high decelerations are required (emergency braking) in combination with a steering input during an emergency evasive maneuver (for example due to a person suddenly appearing on the road), to optimize the interaction of the chassis, wheel torque and steering control in such a way that lateral guidance potential is maximized and collision avoidance (avoiding the obstacle) is achieved in the best possible way, and to increase driving safety when braking into a hairpin bend compared to a conventional ABS or ESP system without controlling active chassis actuators, in which the wheel contact forces on the front axle and rear axle are adapted to the wheel control in such a way that the braking forces can be optimally applied. QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] US 2012 0 085 613 A1

[0008] US 10 752 139 B2

[0008] US 10 746 235 B2

[0008] WO 2021 092 683 A1

[0008]

Claims

[1] Method for operating a motor vehicle (1) or vehicle combination (2), - wherein actual state variables characterising an actual vehicle state are determined, which for at least one, in particular each, of the wheels (4) of the motor vehicle (1) or vehicle combination (2) each comprise at least one component of an actual force vector for forces acting on the respective wheel (4), - wherein target state variables characterising a target vehicle state are specified, which for at least one, in particular each, of the wheels (4) of the motor vehicle (1) or vehicle combination (2) each comprise at least one component of a target force vector for forces to be generated at the respective wheel (4), - whereby a deviation of the actual state variables from the target state variables is determined, - wherein, depending on a respective deviation, a quality functional describing a control quality of a control of the actuators (6-9) assigned to the wheel (4) is determined, - wherein the actuators (6-9) comprise at least a first actuator (6) of a spring-damper system and a second actuator (7-9) of a steering system, braking system and / or drive system of the motor vehicle (1) or vehicle combination (2), - wherein by minimizing the quality function, target values ​​are determined for at least one control variable of each of the actuators (6-9), and - whereby the respective actuators (6-9) are controlled depending on the determined target values. [2] Method according to claim 1, characterized by that the component of the force vector(s) comprises at least one vertical wheel contact force of the wheel (4), a longitudinal force acting on the wheel (4), and / or a transverse force acting on the wheel (4). [3] Method according to one of the preceding claims, characterized by that the actual vehicle condition and the deviation are continuously determined, resulting in a temporal progression of the deviation, which is integrated into the quality functional. [4] Method according to one of the preceding claims, characterized by that the target vehicle state and / or the quality functional are specified or determined depending on at least one specified vehicle property. [5] Method according to claim 4, characterized by that driving safety, driving agility, driving comfort and / or energy consumption are specified as vehicle characteristics. [6] Method according to one of claims 4 and 5, characterized by that a number of vehicle characteristics are assigned a value and a weighting factor and taken into account in the quality functional. [7] Method according to one of the preceding claims, characterized bythat the actual vehicle state and / or the target vehicle state are determined, in particular calculated or estimated on a model-based basis, as a function of at least one input variable characterizing a vehicle movement. [8] Method according to claim 7, characterized by that the input variables recorded are steering angle, wheel speed, yaw rate, pitch rate, roll rate, acceleration, normal force, suspension travel and / or vehicle position. [9] Control device (10), in particular computer device, characterized by that the control device (10) is specially designed to carry out the method according to one of the preceding claims. [10] Motor vehicle (1) or vehicle combination (2), with a plurality of wheels (4) and a plurality of actuators (6-9) each assigned to at least one of the wheels (4), comprising at least a first actuator (6) of a spring-damper system and a second actuator (7-9) of a steering system, braking system and / or drive system of the motor vehicle (1) or vehicle combination (2), characterized by a control device (10) according to claim 9.

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