Method and assistance device for easily realisable smooth cooperation between manual and automated vehicle control, and correspondingly designed motor vehicle

Abstract

The invention relates to a method (13) for controlling a drive system (2) of a motor vehicle (1), to a corresponding assistance device (9), and to a motor vehicle (1) equipped therewith. In the method (13), when there is an abrupt change in a control influence for a total torque to be set by means of the drive system (2), a corresponding torque distribution for allocating the total torque between drive actuators (3) and brake actuators (5) is likewise changed abruptly. At the same time, a correction torque is calculated and applied, which compensates for any difference in the torque contributions of the drive actuators (3) and / or the brake actuators (5) according to the different torque distributions. The drive system (2) is then initially operated using a corresponding new torque distribution modified by applying the correction torque. During further operation, the correction torque is then gradually reduced.

Description

[0001] Method and assistance device for easily implemented smooth cooperation between manual and automated vehicle control and a correspondingly equipped vehicle

[0002] The present invention lies in the field of automotive engineering and relates to a method for controlling a drive system of a motor vehicle. The invention also relates to an assistance device configured for carrying out the method and to a motor vehicle equipped therewith.

[0003] Modern motor vehicles are increasingly equipped with functions and systems to improve user comfort and / or automate driving. However, these vehicles, at least until now, have still been manually controlled by a driver. While this can generally increase user comfort, it can also lead to uncomfortable results or vehicle behavior in certain situations. This can occur, for example, if a driver's action is not compatible with or conflicts with the functionality of a vehicle system, or when switching between automated and manual driving modes, or similar situations.

[0004] One solution involves providing the driver with timely notification of an action, such as switching from electric to combustion engine mode or deactivating cylinder deactivation. German patent DE 102012 108 589 A1 describes a method for operating a motor vehicle with a drive unit designed as a combustion engine, controlled via an accelerator pedal and a corresponding control unit. According to this method, the driver receives haptic feedback from the vehicle indicating that, in response to reaching a specific accelerator pedal travel associated with a particular power demand transmitted to the control unit, a defined action is initiated and executed, resulting in a change of drive mode. This haptic feedback is implemented as a defined free stroke in a stored characteristic curve of the accelerator pedal, starting from the specified accelerator pedal travel.

[0005] Nevertheless, such actions can potentially lead to uncomfortable or irritating reactions or influences for the driver, for example, from the vehicle's drive system. This can also be the case with other approaches. For example, DE 102012 205 522 A1 describes a method for operating a vehicle with an electric motor, in which a fixed transmission ratio between the output torque and the input torque of the electric motor is provided. Furthermore, a driver can request a change in the electric motor's torque using an input device. Upon such a request, the target torque delivered by the electric motor is then changed in steps.

[0006] In particular, cooperation between manual and automated driving, i.e., a driver and a driver assistance system for vehicle control, can present special challenges or requirements. For example, DE 102015 012 377 A1 describes a method for adjusting the brake pressure of a pneumatically actuated friction brake of a motor vehicle. In normal operating mode, a brake pressure is set depending on a driver-specified braking request. When an external braking request, independent of this driver-specified request, is received, a control unit in a pressure control mode applies a resulting brake pressure to the friction brakes, taking into account both the external braking request and the driver-specified braking request.In such an interaction between driver input or requests and automatic measures, particularly in stressed states of a drive system, uncomfortable or irritating jolts may occur, not only during braking but also during acceleration. To avoid this, the contributions of the drive and brake actuators, which together generate a total torque, can in principle be evaluated and adjusted. However, this can also lead to problems, for example, due to mathematical singularities or the generation of undesirably large opposing torques from different actuators.

[0007] The object of the present invention is to avoid the aforementioned problems and to enable, in a particularly simple and robust manner, the comfortable use of a motor vehicle that can be driven manually and at least assisted or at least partially automatically.

[0008] This problem is solved by the subject matter of the main claim and the dependent claims or independent claims. Further possible embodiments of the invention are disclosed in the subclaims, the description, and the figures. Features, advantages, and possible embodiments set forth in the description for one of the subject matter of the independent claims are to be regarded, at least analogously, as features, advantages, and possible embodiments of the respective subject matter of the other independent claims, as well as of any possible combination of the subject matter of the independent claims, optionally in conjunction with one or more of the dependent claims.

[0009] The method according to the invention can be used for or in the control of a drive system of a motor vehicle that can be manually controlled by a driver via pedal operation or guided by a driver assistance system (DAS) that is designed for at least assisted or at least partially automated longitudinal control of the motor vehicle. The drive system comprises at least one drive actuator for generating an accelerating, i.e., positive, drive torque and at least one brake actuator for generating a decelerating, i.e., negative, brake torque. Such a drive actuator can, in particular, be or comprise an electric drive motor. A corresponding brake actuator can, in particular, be or comprise a hydraulic friction brake.

[0010] In the method according to the invention, a sudden, i.e., abrupt or seamless, change in a guiding influence or control variable for a total torque to be provided, i.e., generated, by the drive system via the actuators is automatically detected. Such guiding influences can be a driver of the vehicle or operating actions performed by the driver, in particular pedal actuations, or the driver assistance system. In other words, a driver-desired torque or a target torque requested by the driver assistance system, referred to here as the driver assistance system target torque, can be used as the guiding or determining control variable, or directly as the total torque. The driver-desired torque can be derived from the current position of the operating pedals, i.e., an accelerator pedal or a brake pedal of the vehicle. For the purposes of this method, it is assumed that the brake pedal is not actuated.If the driver does not depress the accelerator pedal, leaving it in a rest position (i.e., at their foot point), the driver's desired torque can, depending on the implementation or configuration, correspond to a predetermined recuperation torque (potentially negative, i.e., decelerating or braking) or a predetermined positive creep torque. This recuperation or creep torque can therefore be a torque that results as the foot point torque, i.e., the driver's desired torque without any manual pedal input. If the driver depresses the accelerator pedal, they can additionally specify or set a pure accelerator pedal torque, which is zero without any manual pedal input and can increase continuously with increasing accelerator pedal depressurization, for example, linearly or according to a predefined characteristic curve.This pure accelerator pedal or actuation torque allows the foot point torque to be reduced first, before the driver's desired torque becomes positive. The driver's desired torque is not determined or influenced by the driver assistance system. The driver assistance system's target torque can be calculated, or may have been calculated, for example, to implement a specific automatically calculated driving maneuver or similar, i.e., to regulate a driver assistance setting.

[0011] As long as the driver assistance system's (DAS) target torque is greater (i.e., more positive) than the driver's desired torque, the DAS can take the lead, at least with regard to longitudinal control (i.e., the vehicle's acceleration behavior), and thus the DAS target torque can be used as the total torque to be provided by the drive system. However, if the driver's desired torque, starting from a lower value, reaches or exceeds the DAS target torque, the driver, or rather the driver's desired torque, can instantly take the lead for longitudinal control (i.e., the vehicle's acceleration behavior). In this case, the driver's desired torque can then be used as the total torque to be provided by the drive system.

[0012] Monitoring of the driver's desired torque and the FAS target torque, or the respective current guidance influence derived therefrom, can be carried out continuously during the operation of the motor vehicle, i.e. continuously or at a predetermined measurement or calculation frequency.

[0013] According to the inventive method, the abrupt change in the steering influence also results in a corresponding abrupt switch between a driver torque distribution setting and a driver assistance system (FAS) torque distribution setting. The driver torque distribution specifies the torque contributions to be provided by the at least one drive actuator and the at least one brake actuator to achieve the driver's desired torque. The foot point torque can also be taken into account. The FAS torque distribution specifies the torque contributions to be provided, i.e., generated, by the at least one drive actuator and the at least one brake actuator to achieve the FAS target torque. The positive torque contributions of the at least one drive actuator and the negative torque contributions of the at least one brake actuator thus sum to the driver's desired torque and the FAS target torque, respectively.

[0014] Although only either the driver's requested torque or the FAS target torque is actually realized, i.e., used as the total torque and provided by the drive system, the different torque distributions can be calculated continuously, for example.

[0015] Even when the driver's desired torque exactly matches the FAS target torque, the driver's torque distribution and the FAS torque distribution can differ. This can be due, for example, to the fact that a different control mechanism, logic, or calculation logic is used to determine the torque distribution in a driver-guided (i.e., manual) ferry operation or operating mode compared to a ferry operation or operating mode guided by the driver assistance system (i.e., at least assisted or at least partially automated). The abrupt change in the torque distribution parameters can therefore, for example, result in a sudden change or...Switching between different calculation logics to determine the currently used torque distribution, i.e., the corresponding torque contributions to be provided by the drive and brake actuators, and / or between different control logics to control the drive system or the actuators of the drive system, which are specified on the one hand for manual, i.e., driver-guided operation and on the other hand for FAS-guided operation of the drive system or the motor vehicle, means or includes.

[0016] For example, if the driver assistance system specifies a target torque of -500 Nm, this can be achieved, for instance, by a combination of a positive torque of 200 Nm generated by the drive actuator and a simultaneous negative torque of -700 Nm generated by the brake actuator. However, depending on the driving or operating situation, there can also be a multitude of other possible combinations of drive and brake torques to generate the respective total torque.

[0017] The torque distributions can be determined or defined, for example, depending on the operating state of the at least one drive actuator and the at least one brake actuator. In doing so, the maximum values ​​adjustable by the actuators, as well as their respective inertia and controllability, can be taken into account. For instance, an actively braking hydraulic friction brake cannot be released instantly to completely eliminate the braking torque it generates. Instead, while the friction brake is being released—a process that takes a certain amount of time, during which the braking torque generated by the friction brake can gradually decrease—the drive actuator can be activated to generate a compensating accelerating torque.

[0018] When the control influence switches from the driver assistance system to the driver or their pedal actions, a change can occur from the driver assistance system's torque distribution to the driver's torque distribution, and vice versa. According to the invention, in the same time step or calculation run in which the torque distribution setting or the calculation or control logic to be used is changed, at least one correction torque is automatically determined or calculated. This correction torque at least partially compensates for the difference between the previously used (i.e., previously active or controlling) torque distribution and the new (i.e., nominally active or used) torque distribution at the time of the change, i.e., the torques or torque contributions to be set by the actuators.The correction moment allows the new moment distribution, to which the system switches during the abrupt change, to be fully or partially aligned with the previously used moment distribution. This correction moment can then be applied to or factored into the new moment distribution. In other words, the new moment distribution can be modified by applying or incorporating the correction moment, resulting in a new moment distribution modified by or around the correction moment.

[0019] In a further step of the inventive process, the drive system or its actuators are then controlled according to the new torque distribution modified by means of the at least one correction torque. In subsequent or further operation, the correction torque is then gradually reduced, i.e., eliminated. In other words, corresponding control signals can be generated for the direct or indirect control of the drive system or the actuators, based on the new torque distribution modified by means of the at least one correction torque. These control signals can then be output, for example, to the drive system or the actuators, a drive control unit, or the like.

[0020] By incorporating the correction torque, the operating states of the actuators immediately prior to the change in the torque distribution setting can be maintained, at least to the extent of the correction or adjustment by the correction torque, in whole or in part, or at least substantially, despite the abrupt nominal change in the active or guiding torque distribution. Thus, despite or as a result of the change, the torques to be provided by the actuators—that is, the accelerating and braking torque contributions to the total torque—do not change, or at least not excessively, or with a jerk or jump perceptible to the driver. Because the driver's desired torque corresponds at least substantially to, and is in particular identical to, the FAS target torque when the guiding influence changes, the total torque also remains unchanged.This allows for a particularly convenient switch between automated and manual driving or operating modes.

[0021] In subsequent operation, i.e., over several or numerous subsequent time or calculation steps and the corresponding further control of the drive system or actuators, the correction torque is then gradually and completely reduced to zero. Once the correction torque is completely reduced, the new torque distribution, associated with the then-active guidance influence, is used to control the drive system or actuators. In other words, the torque distribution can nominally be changed abruptly, but effectively, due to the correction torque and its gradual reduction, the values ​​of the previously used torque distribution and the values ​​of the new torque distribution are blended. This not only achieves a high level of user comfort but also allows for a smooth transition between the different driving or operating modes, both computationally and practically.The control system can be implemented in a particularly simple and robust manner, without placing excessively high loads on the actuators.

[0022] If, for example, the transition from the previous torque distribution to the new torque distribution were to be performed directly, a situation could arise in which the total torque becomes zero. At this moment, it would not be possible to readily calculate the respective share or contribution of the drive and brake actuators to the total torque, as this would potentially result in division by zero. If this were circumvented by always leaving at least a predetermined minimum torque, very high torque contributions from individual actuators could occur during the transition, i.e., when blending from the previous torque distribution to the new one. This is particularly disadvantageous in a stressed state, for example, with regard to actuator load, wear, energy consumption, or the like. These problems can be circumvented simply, effectively, and robustly by the present invention.In one possible embodiment of the present invention, the driver's desired torque and the FAS target torque are continuously and automatically monitored. The abrupt change in the steering influence is detected when the curves of the driver's desired torque and the FAS target torque meet or intersect.

[0023] In particular, the abrupt change in the steering influence can be recognized when the driver's desired torque, starting from a lower value, just reaches the FAS target torque, or when the driver's desired torque falls below the FAS target torque. In other words, the driver's desired torque can be used as the total torque, and thus the driver's desired torque, or the driver's behavior, can be used as the steering influence, when the driver's desired torque corresponds to the FAS target torque.

[0024] In an example scenario, the driver's desired torque might initially match the pedal-point torque, and the driver assistance system's (DAS) target torque might be greater than the pedal-point torque. In this case, the DAS takes the lead, and the target torque is used as the total torque. When the driver then depresses the accelerator pedal, the driver's desired torque can increase accordingly. However, there may be a certain amount of free play, meaning a range of position or angle through which the accelerator pedal must be moved or actuated by the driver without any change in the total torque, i.e., the behavior, movement, or acceleration of the vehicle.Over this initial period of free play, the negative pedal-point torque intended for recuperation without pedal input can first be reduced or overcome. Then, by further, i.e., even stronger, application of the accelerator pedal, the driver can apply or specify the torque required by the driver assistance system (FAS) as the target torque. Accordingly, when the driver's requested torque reaches the FAS target torque, the driver can abruptly take over, and the change in steering influence is detected.

[0025] The embodiment of the present invention proposed here offers a simple, effective, and robust method for detecting changes in the steering influence, since means for detecting the driver's desired torque and the driver assistance system's (FAS) target torque are already present in the vehicle. In a further possible embodiment of the present invention, the abrupt change in the steering influence is detected by a jump in a blending factor. This blending factor determines a gradual blend between the driver's desired torque and the FAS target torque and changes its value abruptly when the driver overrides the driver assistance system, i.e., the FAS target torque, by applying a sufficiently strong amount of pressure to the accelerator pedal of the respective vehicle. The progression of this blending factor can therefore be continuously monitored.Such a blending factor can enable a particularly high level of driving comfort in other driving or operating situations. Thus, this blending factor alone can achieve a particularly high level of driving comfort. Furthermore, this blending factor allows for the easy and quick detection of abrupt changes in steering influence, as only a single value needs to be evaluated.

[0026] In a further possible embodiment of the present invention, the respective correction torque, i.e., its current value, is added to the torque contribution to be provided by the at least one or the respective actuator according to the new torque distribution. This actuator is then controlled to provide a resulting corrected torque or torque contribution. Depending on the implementation and driving or operating situation, or depending on whether the torque contribution of a drive actuator or a brake actuator is modified by means of the respective correction torque, the correction torque can be positive or negative. In the embodiment of the present invention proposed here, the torque contribution to be provided by the respective actuator according to the new torque distribution and the corresponding correction torque can be added to calculate the corrected torque contribution to be provided by the respective actuator.Such an additive calculation can be performed simply and with minimal effort, and therefore particularly quickly. Thus, within a single time or calculation step, or within a single cycle of a drive control system, the change in torque distribution, the determination of the correction torque, and the calculation of the modified torque contribution or the modified new torque distribution can be carried out. This allows the aforementioned jerks or jolts that could otherwise occur during the change to be avoided particularly effectively and reliably. In a further possible embodiment of the present invention, the difference in the torque contributions to be set, i.e., used, according to the previously used torque distribution and the new torque distribution, is calculated or calculated within the same cycle of the change, i.e., for the initial control of the actuators during or after the change.The operating states of the actuators are completely compensated by the correction torque. In other words, the correction torque can be calculated so that the resulting new torque distribution exactly matches the previous torque distribution. The magnitude of the correction torque can be the change or jump in torque or torque contribution resulting from a comparison of the previous torque distribution with the new torque distribution. The proposed embodiment of the present invention limits or significantly reduces the computational effort required during the switching cycle. Furthermore, it reliably prevents the aforementioned jerks or jolts.

[0027] Provided sufficient time or computing power is available, the correction torque could alternatively be calculated slightly less than the aforementioned difference during the journal or cycle of the changeover. This could potentially accelerate the transition to the new torque distribution by one journal or cycle. The initial difference between the previously used torque distribution and the new torque distribution modified by the correction torque can be set so small that it does not result in a noticeable jerk or jolt.

[0028] In a further possible embodiment of the present invention, a respective correction torque is determined individually, i.e., independently, for the torques to be provided by the drive and brake actuators, i.e., the corresponding torque contributions. In other words, the positive or accelerating torque contributions can be corrected by a separate correction torque. Likewise, the negative or braking torque contributions can be corrected by a separate correction torque. In particular, an individual correction torque can be determined for each individual actuator of the drive system. The embodiment of the present invention proposed here takes into account that, during the switching process, the various torque distributions can differ almost arbitrarily with respect to the torque contributions to be provided by the drive actuators on the one hand and the brake actuators on the other.Furthermore, if the drive system comprises multiple drive actuators and / or multiple brake actuators, the various torque distributions can also provide or define different operating states for the multiple individual drive actuators, which together provide the total positive torque contribution, and / or for the multiple brake actuators, which together provide the total negative torque contribution. By determining or using multiple or individual correction torques as provided here, the method according to the invention can thus be applied or used in a particularly large number of different situations and with particular flexibility.

[0029] In a possible further development of the present invention, the various correction torques for the drive and brake actuators are reduced by gradients of identical magnitude after the abrupt change. Such a gradient can, for example, be a specific value in Nm / s or the like. The correspondingly identical reduction or decay rate of the various correction torques ensures that the correct total torque is always applied, even if the total torque to be applied changes during the decay of the correction torques.

[0030] In a further possible embodiment of the present invention, at least one correction torque is calculated only when the drive system or its actuators are in a pre-stressed state. In other words, the method according to the invention, as described, can only be applied, for example, in pre-stressed states of the drive system or the actuators. In such a pre-stressed state, at least one drive actuator and at least one brake actuator are active simultaneously, so that the drive actuator works against the brake actuator. The total torque then results from the sum or balance of the torques generated by the at least one drive actuator and the at least one brake actuator, i.e., the corresponding torque contributions of the actuators.If the drive system is not in a preloaded state, i.e., in an unpreloaded state, then, for example, only drive actuators or only brake actuators can be active, i.e., apply a torque. In such a case, the system can switch to the new torque distribution without a corrective torque and without any sudden jump or jolt, since the total torque remains unchanged at the moment of the switch. Therefore, the computational effort otherwise required for the method according to the invention can be saved in such cases. For example, continuous monitoring of the currently active or used torque distribution can be performed to determine whether it is in a preloaded state or not.As soon as and as long as this is the case, for example a corresponding trigger or flag or the like can be set to ensure that, when a change in the guiding influence is detected as described, the inventive method is applied, i.e., the correction torque is determined and applied.

[0031] The present invention also relates to an assistance device for a motor vehicle. The assistance device according to the invention comprises a data processing unit and is configured for the execution, i.e., application, of the method according to the invention, particularly automatically. For this purpose, the data processing unit can, for example, include a process unit, such as a microchip, microprocessor, microcontroller, or the like, and a computer-readable data storage device coupled thereto. This data storage device can then, for example, contain a corresponding operating or computer program that encodes or implements the process steps, measures, or sequences described in connection with the method according to the invention, or corresponding control instructions. This operating or computer program can then be executed by means of the process unit in order to execute the corresponding method or to effect its execution.Similarly, the assistance device, for example as part of the data processing unit, can have an input interface for acquiring moment data indicating the driver's desired torque and the FAS target torque, and an output interface for outputting a determined or generated output depending on this, such as data or control signals for the drive system. The assistance device according to the invention can be a separate or independent unit or integrated into a more comprehensive vehicle system and / or have further functions. For example, the assistance device can be integrated into the drive system.

[0032] The present invention also relates to a motor vehicle comprising an accelerator pedal operable by a driver for manual vehicle control and the aforementioned driver assistance system for at least assisted or at least partially automated longitudinal control of the motor vehicle. The motor vehicle according to the invention is also equipped with the assistance device according to the invention, and thus configured accordingly for, in particular automatically, execution of the method according to the invention. The motor vehicle according to the invention may, in particular, be the motor vehicle mentioned in connection with the method according to the invention and / or in connection with the assistance device according to the invention, or correspond to it.

[0033] Further features of the invention may become apparent from the claims, the figures, and the description of the figures. The features and combinations of features mentioned above in the description, as well as the features and combinations of features shown below in the description of the figures and / or in the figures themselves, can be used not only in the combinations specified, but also in other combinations or on their own, without departing from the scope of the invention.

[0034] The drawing shows in:

[0035] Fig. 1 shows a schematic representation of a motor vehicle equipped for a smooth transition between at least partially automated driving and manual driving; and

[0036] Fig. 2 shows an exemplary schematic flow chart to illustrate a corresponding procedure for controlling a motor vehicle drive system.

[0037] Fig. 1 shows a schematic representation of a motor vehicle 1 with a drive system 2. This drive system 2 includes, by way of example, an electric machine 3 as the drive actuator. The motor vehicle 1 also has a traction battery 4 for supplying the electric machine 3 and a braking system 5. The braking system 5 can include at least one hydraulic friction brake as the brake actuator. The traction battery 4 and / or the braking system 5 can also be part of the drive system 2. The motor vehicle 1 can be controlled by a driver 6 in manual operation or operating mode. For this purpose, the driver 6 can, for example, operate an accelerator pedal 7, which is shown schematically here.Similarly, the motor vehicle 1 may, for example, have a brake pedal that the driver 6 can manually operate to decelerate the motor vehicle 1 using the braking system 5, although this brake pedal is not explicitly shown here for the sake of clarity. Likewise, the motor vehicle 1 has a driver assistance system 8 for controlling or guiding the motor vehicle 1 in at least an assisted or at least partially automated driving or operating mode. For this purpose, the driver assistance system 8 can control the drive system 2 or its actuators as needed.

[0038] If a target torque requested by the driver assistance system 2 (i.e., a target torque for regulating a setting of the driver assistance system 8) is higher than a driver's foot point (i.e., a foot point torque or recuperation torque derived from the rest position of the accelerator pedal 7), then a free-running behavior may initially occur when the driver 6 depresses the accelerator pedal 7. As soon as a driver-requested torque, specified by the driver 6 through sufficiently strong depression of the accelerator pedal 7, reaches or exceeds the target torque of the driver assistance system 8, the driver 6 takes over control of the drive system 2, i.e., the control of the vehicle 1. This allows for an instantaneous, i.e., abrupt, switch from the control logic used by the driver assistance system 8 to the control logic specified for manual driving operation to control the drive system 2 or its actuators.Such a control logic can determine a torque distribution within the drive system 2, i.e., a division of a total torque to be realized - here depending on the situation of the FAS target torque or the driver's desired torque - onto the different actuators of the drive system 2, here for example the electric machine 3 and the brake system 5 or its at least one hydraulic friction brake.

[0039] This can be potentially problematic whenever the drive system 2 is in a state of tension or the vehicle 1 is traveling in a state of tension, because the torque distribution between the drive actuators and brake actuators of the drive system 2 can differ between pure driver operation (i.e., manual vehicle control by the driver 6) and pure driver assistance operation (i.e., driver torque distribution). In pure driver assistance operation, i.e., at least partially or conditionally automated vehicle control by the driver assistance system 8 (ADAS torque distribution), the torque distribution can differ. In such a case, the abrupt change between different tension states, i.e., the different torque distributions, can lead to jerks or jolts when the driver 6 takes control of the drive system 2, thus overriding the driver assistance system 8.

[0040] To avoid this, the motor vehicle 1 is also equipped with a suitably configured assistance system 9. This assistance system 9 is schematically represented separately here by an interface 10, a processor 11, and a computer-readable data storage device 12 coupled to it. The assistance system 9 can also be combined with the driver assistance system 8, integrated into the drive system 2, or the like. The aforementioned devices and systems can, for example, be connected or coupled to each other via the vehicle 1's electrical system.

[0041] To avoid the aforementioned shocks in drive system 2, the assistance device 9 is configured to allow the abrupt change in torque distribution, i.e., the corresponding change in the control of drive system 2 or the actuators, but simultaneously, i.e., not in the same step, to calculate a correction torque and subtract it from the abrupt control, thus modifying the new torque distribution with the correction torque. The correction torque can be selected so that no abrupt change occurs. The correction torque, or its magnitude, can therefore correspond in the first step to the otherwise occurring jump height, i.e., the difference in torque contributions according to the different torque distributions, but with the opposite sign or influence on the respective torque contribution or the total torque. The correction torque is then reduced over time.

[0042] This ensures that the total torque generated by the drive system 2, i.e., the sum of the torque contributions from the drive and brake actuators, is always correct. Likewise, the torque distribution always follows the active steering influence without delay, i.e., whichever takes priority with regard to vehicle guidance. Simultaneously, a smooth transition occurs, meaning a seamless and jerk-free adjustment of the actual operating states or torque contributions of the actuators. For further illustration, Fig. 2 shows an exemplary schematic flowchart 13 for a corresponding procedure.

[0043] Accordingly, in process step S1, the motor vehicle 1 or the assistance device 9 can be put into operation. Subsequently, in process step S2, continuous monitoring for a change in the steering influence for the vehicle guidance can be started and carried out.

[0044] If a sudden change in the control influence is detected, the process jumps to a process step S3. Several different actions can be performed in this process step S3. First, in process step S3a, the torque distribution to be used or relevant for the drive control can be changed in a similarly abrupt manner, corresponding to the detected sudden change in the control influence. Second, in process step S3b, correction torques can be calculated to compensate for the respective jump in the torque contributions of the drive and brake actuators, based on a nominal jump in the torque contributions resulting from the change in the torque distribution. Finally, in process step S3c, the correction torques can be subtracted from or added to the corresponding torque contributions.In process step S3c, a new torque distribution modified by the correction torques can be determined. This is carried out in particular before the drive and brake actuators are controlled or operated for the first time according to the new torque distribution.

[0045] In a process step S4, the drive system 2 or its actuators can be controlled for the first time according to the modified new torque distribution.

[0046] In process step S5, it can be checked whether the magnitude of at least one correction torque is greater than zero. If this is the case, the correction torque for a subsequent magazine or control cycle can be reduced in process step S6, in particular with a predefined or dynamically determined gradient, for example, depending on the magnitude of the initial correction torque determined in process step S3. The resulting reduced correction torque leads to a correspondingly further adapted or modified torque distribution. The drive system 2 or its actuators can then be controlled or operated using or according to this torque distribution.

[0047] This process can be repeated until, in a pass of process step S5, it is determined that the correction torque or all correction torques have been completely eliminated.

[0048] Accordingly, from this point onwards, the drive system 2 can be controlled or operated according to the new torque distribution, which will then no longer be modified.

[0049] Overall, the examples described show how improved cooperation between automated and manual driving can be realized and applied, especially for tense conditions.

[0050] Reference symbol list

[0051] 1 motor vehicle

[0052] 2 Drive system

[0053] 3 electric machine

[0054] 4 batteries

[0055] 5. Braking system

[0056] 6 drivers

[0057] 7 Accelerator pedal

[0058] 8 Driver assistance systems

[0059] 9 Assistance facility

[0060] 10 Interface

[0061] 11 processor

[0062] 12 Data storage devices

[0063] 13. Schedule

[0064] S1-S6 process steps

Claims

Patent claims 1. Method (13) for controlling a drive system (2) of a motor vehicle (1), wherein the drive system (2) comprises a drive actuator (3) for generating an accelerating drive torque and a brake actuator (5) for generating a decelerating brake torque and automatically - a sudden change in a guidance influence for a total torque to be provided by the drive system (2) is detected, wherein the guidance influence may be a driver (6) of the motor vehicle (1) or a driver assistance system (8) of the motor vehicle (1) equipped for at least assisted longitudinal guidance, - with the change in the steering influence, there is also a corresponding abrupt switch between a specification for a driver torque distribution and a specification for an FAS torque distribution, whereby the driver torque distribution specifies torque contributions to be provided by the drive actuator (3) and the brake actuator (5) to realize a driver desired torque derived from a pedal position of the vehicle (1), and the FAS torque distribution specifies torque contributions to be provided by the drive actuator (3) and the brake actuator (5) to realize a target FAS torque requested by the driver assistance system (8), and a correction torque is also determined which at least partially compensates for a difference in the operating states of the actuators (3, 5) to be used according to the previously used torque distribution and the new torque distribution, - the drive system (2) is controlled according to the new torque distribution modified by means of the correction torque and the correction torque is gradually reduced during subsequent operation.

2. Method (13) according to claim 1 , characterized in that the driver request torque and FAS target torque are continuously monitored and the abrupt change in the guidance influence is detected when the curves of the driver request torque and the FAS target torque meet.

3. Method (13) according to one of the preceding claims, characterized in that the abrupt change of the guidance influence is detected by means of a jump in a blending factor which determines a gradual blending between the driver's desired torque and the FAS target torque and which abruptly changes its value when the driver (6) overrides the FAS target torque.

4. Method (13) according to one of the preceding claims, characterized in that the respective correction torque is added to the torque contribution to be provided by the respective actuator (3, 5) according to the new torque distribution and this actuator (3, 5) is controlled to provide a resulting corrected torque.

5. Method (13) according to one of the preceding claims, characterized in that in the journal of the change the difference in the operating states of the actuators (3, 5) to be used according to the previously used moment distribution and the new moment distribution is completely compensated by the correction torque.

6. Method (13) according to one of the preceding claims, characterized in that a respective correction torque is determined individually for the torques to be provided by the drive and brake actuators (3; 5), in particular by each individual actuator (3, 5) of the drive system (2).

7. Method (13) according to claim 6, characterized in that the various correction torques for the drive and brake actuators (3; 5) are reduced with gradients of identical magnitude.

8. Method (13) according to one of the preceding claims, characterized in that The correction torque is calculated only if the drive system (2) is in a stressed state.

9. Assistance device (9) for a motor vehicle (1), wherein the assistance device (9) comprises a data processing device (10, 11, 12) and is configured to perform the method (13) according to one of the preceding claims.

10. Motor vehicle (1) comprising an accelerator pedal (7) operable by a driver (6) of the motor vehicle (1) for manual vehicle control and a driver assistance system (8) for at least assisted longitudinal control of the motor vehicle (1) and the assistance device (9) according to claim 9.

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