Method and control unit for operating a vehicle and vehicle

Abstract

The invention relates to a method for operating a vehicle (100), wherein the method comprises a step of determining a speed profile for at least one driving segment of a journey of the vehicle (100) using at least one vehicle information, at least one environmental information and / or at least one driver information of a driver of the vehicle (100), a step of comparing the speed profile with reference data representing a target speed profile for the driving segment and / or at least one limit value to obtain a comparison result representing a deviation between the speed profile and the reference data, and a step of controlling a device (102) for braking the vehicle (100) using the comparison result.

Description

State of the art

[0001] The invention relates to a method and a control unit for operating a vehicle, as well as to a vehicle according to the preamble of the independent claims. The present invention also relates to a computer program.

[0002] In motorsport, high speeds are typically reached, which is why safety features are crucial for the driver. These safety features include Race Speed ​​Assist and Predictive Curve Control (PCC), which calculates a target speed based on a desired lateral acceleration and the curvature of the road, and then regulates the vehicle to maintain that speed. Other features include Race Track Assist (RTA), which uses augmented reality (AR) to display the ideal trajectory on a race track to the driver. Disclosure of the invention

[0003] Against this background, the approach presented here introduces an improved method for operating a vehicle, an improved control unit that uses this method, and finally a corresponding computer program and an improved vehicle according to the main claims. The measures listed in the dependent claims enable advantageous further developments and improvements of the device specified in the independent claim.

[0004] The presented approach offers a way to improve driving skills and enhance driving safety on a racetrack by providing driver feedback and limiting system interventions in longitudinal dynamics. Advantageously, driving recommendations can be generated based on track and vehicle conditions. Furthermore, a performance limit can be determined before any adverse effects occur. Additionally, a potential speed can be identified without ever having been reached, and / or the driver can be safely guided to the maximum possible vehicle performance.

[0005] A method for operating a vehicle is presented, comprising a step of determining a speed profile for at least one segment of the vehicle's journey using at least one piece of vehicle information, at least one piece of environmental information, and additionally or alternatively at least one piece of driver information from the vehicle's driver. The method further comprises a step of comparing the speed profile with reference data representing a target speed profile for the journey segment and additionally or alternatively at least one limit value, in order to obtain a comparison result that represents a deviation between the speed profile and the reference data. The method further comprises a step of controlling a device for braking the vehicle using the comparison result.

[0006] The method can be implemented in a vehicle, such as a racing car. However, it can also be applied to passenger cars or trucks. The speed profile, for example, can include a variety of different values. Accordingly, the at least one piece of vehicle information can include, for example, specific road friction coefficient data (obtained via the vehicle's ESP functionality), vehicle speed data, vehicle mass, vehicle type or exact model including its characteristics, and additionally or alternatively, the vehicle's pose (position and orientation) on the road section. The at least one piece of environmental information can advantageously include environmental conditions, such as weather, road surface quality, or more detailed information regarding the route traveled.Such data can include, for example, the position of curves, their curve radii, road gradients, lane widths, etc., along the driving segment. At least one piece of driver information can advantageously relate to a specific driver and, for example, their driving performance. This means that driver-typical maneuvers and trajectories, times, and, additionally or alternatively, speed profiles can be considered in the process. In the comparison step, the specific speed profile can then be compared with the reference data. The reference data can, for example, represent optimal or maximum possible driving performance, but real-world comparative values, such as those from comparison drives and, additionally or alternatively, from a comparison vehicle, can also be used as reference data in the process.Advantageously, driver safety can be increased because the process can prevent the vehicle from leaving the roadway. This can advantageously reduce the risk of accidents, as braking can be initiated automatically if the driver fails to apply the appropriate braking force by the latest possible moment. For example, the reference data can represent a model-based calculated reference driving performance. Furthermore, a performance limit for the vehicle can be determined early on, a maximum possible vehicle performance can be calculated, and the driver can be guided accordingly. Preferably, this can increase driver safety.

[0007] According to one embodiment, in the determination step, an actual trajectory for the vehicle can be determined using vehicle information, environmental information, and additionally or alternatively, driver information. In the comparison step, the actual trajectory can be compared with further reference data representing a target trajectory to obtain a further comparison result that can represent a deviation between the actual and target trajectories. In the control step, the device can be controlled using the comparison result to approximate the actual trajectory to the target trajectory. The two trajectories can thus advantageously be compared for analysis. For example, this allows the driver to adjust and improve their driving performance.

[0008] Furthermore, the comparison step can yield at least one limit value representing a realistic maximum speed for the vehicle on the journey segment and, additionally or alternatively, the braking force required to decelerate the vehicle at the latest possible braking point, depending on the maximum speed for the journey segment. Advantageously, this allows the braking point to be maintained and thus reduces the risk of the vehicle leaving the roadway.

[0009] According to one embodiment, the speed profile can be determined in the determination step using a modified or further developed Kamm circle. Advantageously, for example, an ideal and, additionally or alternatively, a real braking point for the vehicle for the route can be calculated using the modified or further developed Kamm circle. The known standard Kamm circle represents an idealized relationship between longitudinal and lateral forces at the wheel of a vehicle. In contrast to the known standard Kamm circle, the modified or further developed Kamm circle according to one embodiment includes, for example, the third dimension of speed.

[0010] Furthermore, in a repeated determination step, a current speed profile for at least one further segment of the journey can be determined using at least one additional piece of vehicle information, at least one additional piece of environmental information, and additionally or alternatively at least one additional piece of driver information. In a repeated comparison step, the current speed profile can be compared with the reference data to obtain a current comparison result that can represent a deviation between the current speed profile and the reference data. In a repeated control step, the vehicle's device can be controlled using the current comparison result.

[0011] For example, by repeating the process steps, an up-to-date comparison result can always be obtained, allowing the vehicle to advantageously react to new conditions, such as tire wear. This can further enhance driver safety.

[0012] The method can further include a step of outputting a display signal to show the speed profile and, additionally or alternatively, the reference data via an interface to a display device in the vehicle. Advantageously, the driver can analyze their driving performance and preferably adjust their driving style within safe parameters. Advantageously, specific recommendations for improving vehicle control to achieve faster and safer lap times can be provided.

[0013] According to one embodiment, a warning signal can be issued to the driver during the output step when at least one limit value has been reached. Advantageously, the warning signal can be a visual, audible, and additionally or alternatively a haptic signal, such as an LED, a warning tone, or a vibration. Advantageously, the warning signal can be issued when a point in time and, additionally or alternatively, a speed is reached at which braking of the vehicle should preferably be initiated. Advantageously, the intensity of the warning signal can be increased as the latest possible braking point approaches.

[0014] Furthermore, the procedure can include a step of locating the vehicle on the route using GPS in order to generate vehicle information for determining the speed profile along the route. Advantageously, the speed profile can be determined more accurately.

[0015] According to one embodiment, the reference data can be read in via an interface to an external device. For example, the reference data can be received online from the external device or via a cloud. The reference data can be generated, for example, from comparable vehicles, drivers, and / or routes. Alternatively, the reference data can also be stored offline.

[0016] At least during the steering step, according to one embodiment, no automatic intervention in the vehicle's steering can occur. For example, the procedure can be carried out while the vehicle is being steered purely manually.

[0017] This process can be implemented, for example, in software or hardware, or in a hybrid form of software and hardware, for example in a control unit.

[0018] The approach presented here further creates a control unit that is configured to perform, control, or implement the steps of a variant of the method presented here in appropriate devices. This embodiment of the invention in the form of a control unit also allows the problem underlying the invention to be solved quickly and efficiently.

[0019] For this purpose, the control unit can have at least one processing unit for processing signals or data, at least one storage unit for storing signals or data, at least one interface to a sensor or actuator for reading sensor signals from the sensor or for outputting control signals to the actuator, and / or at least one communication interface for reading or outputting data embedded in a communication protocol. The processing unit can be, for example, a signal processor, a microcontroller, or the like, while the storage unit can be flash memory or a magnetic storage device.The communication interface can be configured to read or output data wirelessly and / or via wired connections, whereby a communication interface that can read or output wired data can, for example, read this data electrically or optically from or output it into a corresponding data transmission line.

[0020] In this context, a control unit can be understood as an electrical device that processes sensor signals and outputs control and / or data signals accordingly. The control unit can have an interface, which can be implemented in hardware and / or software. In the case of a hardware-based interface, the interfaces can, for example, be part of a so-called system ASIC, which incorporates various functions of the control unit. However, it is also possible that the interfaces are separate integrated circuits or at least partially comprised of discrete components. In the case of a software-based interface, the interfaces can be software modules, which, for example, are located on a microcontroller alongside other software modules.

[0021] Also advantageous is a computer program product or computer program with program code that can be stored on a machine-readable carrier or storage medium such as a semiconductor memory, a hard disk memory or an optical memory and is used to carry out, implement and / or control the steps of the method according to one of the embodiments described above, in particular if the program product or program is executed on a computer or device.

[0022] Furthermore, a vehicle is presented with a device for braking the vehicle and a control unit in a previously mentioned variant, which is coupled to the device.

[0023] The vehicle can be, for example, a racing car or a standard passenger car. Alternatively, the vehicle can also be a truck. The device can, for example, include the vehicle's transmission system and preferably a braking system, an accelerator pedal, and additionally or alternatively, a steering system.

[0024] Examples of the approach presented here are shown in the drawings and explained in more detail in the following description. It shows: Fig. 1 a schematic representation of a vehicle according to an exemplary embodiment; Fig. 2 a schematic representation of a route with a plurality of sections according to an exemplary embodiment for a vehicle. Fig. 3 a flowchart of an exemplary embodiment of a method for operating a vehicle; Fig. 4 a block diagram of a control unit according to an exemplary embodiment; Fig. 5 a velocity-distance diagram of a velocity profile according to an exemplary embodiment, and Fig. 6 a representation of a further developed Kamm circle.

[0025] In the following description of favorable embodiments of the present invention, the same or similar reference numerals are used for the elements shown in the various figures and acting similarly, without repeating these elements.

[0026] Fig. Figure 1 shows a schematic representation of a vehicle 100 according to an exemplary embodiment. According to this embodiment, the vehicle 100 is implemented as a racing car. According to this embodiment, the vehicle 100 has a device 102, which includes, for example, an acceleration unit, a braking unit, and / or a steering unit. The device 102 can also be used for other vehicles. Furthermore, the vehicle 100 has a control unit 104, which is configured to control and / or execute a method for operating the vehicle 100, as is described, for example, in Fig. 3 is described in more detail. The control unit 104 is coupled to the device 102.

[0027] According to this embodiment, the vehicle 100 also has a communication unit as an interface 106, which is configured to wirelessly receive signals from, for example, an external device 108 and provide them to the control unit 104. Furthermore, according to this embodiment, the vehicle 100 has a sensor device 110, which, for example, has at least one and, in particular, a plurality of sensors. The sensor device 110 is configured, for example, to acquire at least one piece of vehicle information, at least one piece of driver information, and / or at least one piece of environmental information and provide it to the control unit 104, where it is processed, for example.

[0028] Racetrack enthusiasts appreciate online visualizations of continuous lap times compared to a reference lap, as well as offline visualizations of driving data such as speed, drift angle, time difference, and driving line / trajectory when comparing multiple laps, for example, from different drivers. Displaying braking points or the ideal line / trajectory in the instrument cluster or head-up display is less popular.

[0029] Against this background, a method is described for comparing a driver's actual driving performance—meaning trajectory, speed profile, and / or lap time—with a model-based calculation of the maximum possible driving performance. This is done both for training purposes and as a safety feature for the vehicle. This means that with the function described here, it is no longer possible to "overbrake" or leave the track at any point due to excessive speed. In other words, driving errors are corrected by using the accelerator and brake pedals; the only remaining risk on a racetrack is incorrect steering input.

[0030] Therefore, the approach described here can also be advantageously carried out when the vehicle is steered purely manually, i.e., when an optionally available steering assistance device for carrying out automatic steering interventions is deactivated.

[0031] Fig. Figure 2 shows a schematic representation of a journey 200 with a plurality of journey sections 202, 204, 206, 208 according to an exemplary embodiment for a vehicle such as is found, for example, in Fig. 1 was described. According to this embodiment, journey 200 corresponds to an optimal trajectory for the vehicle for a journey distance 201, which is chosen only as an example for illustration purposes.

[0032] Route 201 has two opposing straight sections 210 and 212, and two opposing curved sections 214 and 216, each connecting the straight sections 210 and 212 on one side. Section 202 lies on section 210, section 204 on section 212, section 206 on section 214, and section 208 on section 216.

[0033] Sections 206 and 208 each feature a curve with a different diameter. Within these curves, sections 206 and 208 lie on the inside of sections 214 and 216, while sections 202 and 204 run on the outside of the straight sections 210 and 212.

[0034] Fig. Figure 3 shows a flowchart of an embodiment of a method 300 for operating a vehicle, as is found, for example, in Fig. As described in section 1, procedure 300 includes step 302 of determining a speed profile for at least one segment of a vehicle's journey using at least one piece of vehicle information, at least one piece of environmental information, and / or at least one piece of driver information. The vehicle information represents, for example, friction coefficient data, speed data, the vehicle's mass, its pose (position and orientation) on the track, and / or its vehicle type and model. The environmental information represents, for example, the vehicle's position or location, or information regarding a specific race track. Optionally, the environmental information also represents, for example, environmental conditions, road surface characteristics, weather, and whether the road surface is wet.The driver information refers, for example, to a specific driver of the vehicle as well as to his driving performance and / or his speed profile and / or associated trajectory driven, his lap time required to complete the route or trajectory, as is the case, for example, in . Fig. The procedure 300 further comprises a step 304 of comparing the speed profile with reference data, which represent a target speed profile for the journey segment and / or at least one limit value, in order to obtain a comparison result that represents a deviation between the speed profile and the reference data. The reference data represent, for example, a maximum possible and thus, for example, an optimal driving performance for the journey or a maximum possible driving performance with real-world comparison values. The reference data are only optionally read in via an interface to an external device. The procedure 300 also comprises a step 306 of controlling a device for braking or decelerating the vehicle, such as a brake and / or an accelerator pedal, using the comparison result.This means that a performance limit for the vehicle is detected early and that the driver is optionally guided if they have not initiated braking with the appropriate braking force up to a calculated braking point. For example, a reference driving performance is calculated using a model.

[0035] According to this embodiment, method 300 further comprises a step 308 of locating the vehicle on the route using GPS in order to generate the vehicle information for determining the speed profile over the route. Optionally, method 300 also includes a step 310 of outputting a display signal to show the speed profile and / or reference data via an interface to a display device in the vehicle. This allows the driver, for example, to view and / or analyze their own data. For example, in step 310, a warning signal is issued to the driver when at least one limit value has been reached. The warning signal is issued, for example, as a visual and / or haptic warning signal, such as a vibration that can increase in intensity as the latest possible braking point approaches.The limit value refers, for example, to a specific time and / or speed at which the vehicle is braked. For instance, in step 304 of the comparison process, at least one limit value is obtained that represents a realistic maximum speed for the vehicle on the journey segment and / or the braking force required to decelerate the vehicle at the latest possible braking point, depending on the maximum speed for the journey segment. This ensures that the braking point is maintained and thus reduces the risk of the vehicle leaving the roadway.

[0036] According to this embodiment, in step 302 of the determination process, an actual trajectory for the vehicle is additionally determined using vehicle information, environmental information, and / or driver information. Consequently, in step 304 of the comparison process, the actual trajectory is compared with further reference data representing a target trajectory to obtain a further comparison result that represents a deviation between the actual trajectory and the target trajectory. In step 306 of the control process, for example, the device is controlled using the comparison result to approximate the actual trajectory to the target trajectory.

[0037] Only optionally, in step 302 of the determination process, the speed profile is determined using the further developed Kamm circle. Also optionally, in a repeated step 302 of the determination process, a current speed profile for at least one further segment of the journey is determined using at least one additional piece of vehicle information, at least one additional piece of environmental information, and / or at least one additional piece of driver information. Consequently, in a repeated step 304 of the comparison process, the current speed profile is compared with the reference data to obtain a current comparison result that represents a deviation between the current speed profile and the reference data. In a repeated step 306 of the control process, the vehicle's device is controlled using the current comparison result.

[0038] According to one embodiment, at least during step 306 of the activation process, no automatic intervention in the vehicle's steering is performed. For example, no automatic intervention in the steering is performed while the procedure is actively running. Thus, the driver can steer the vehicle manually while the procedure is active and, if necessary, automatically applies the brakes.

[0039] In other words, the presented approach triggers automatic braking at the very last possible braking point. Depending on driving skill and perceived safety, this braking point can also be continuously advanced using a model, for example, by setting the friction coefficient utilization during braking to values ​​less than 1 or by deviating inwards from the modified Kamm circle in the case of superimposed deceleration and lateral acceleration conditions. This means that the driver retains complete control, provided they do everything correctly, while simultaneously having the assurance that they will not leave the track due to braking too late or for too short a time. This can eliminate a large portion of the accident risk on racetracks.

[0040] The vehicle in which the procedure 300 is carried out has, for example, today's standard ESP or airbag sensors for recording steering angle, accelerations and yaw rates around all three axes and / or driver input, as well as GNSS sensors.

[0041] The driver, or rather the accelerator and / or brake pedals operated by the driver, are actively intervened to limit or increase the speed according to a model-based calculated speed profile. The three essential elements of the function are a setpoint generator, which determines how fast the vehicle can travel on a given trajectory; a localization, which determines which setpoint is currently valid for the current trajectory; and a control system, which limits the speed in a way that is comfortable for the driver.

[0042] Localization is based, for example, on data fusion between GPS positioning and vehicle condition monitoring using a 6D sensor. Alternatively or optionally, semantic localization using optical sensors such as cameras or lidar in semantic maps is conceivable. The model-based calculated speed profile is based on mathematical descriptions of vehicle behavior, such as an advanced Kamm circle for the vehicle model, the driving line or trajectory, and the road surface condition. The models for calculating the speed profile can be extended to include additional effects such as variable lane width, variable coefficient of friction, air resistance, road topology, and cross slope.

[0043] By scaling the vehicle's dynamic characteristics, such as engine power, coefficient of friction, and / or aerodynamic downforce, the speed profile can be adjusted incrementally, allowing for control interventions such as multi-stage traction control. For example, a vehicle from a particular manufacturer might be limited in the first stage to the level of a compact car from that manufacturer, in the second stage to the level of a sports sedan from that manufacturer, in the third stage to the level of a high-performance sports sedan from that manufacturer, in the fourth stage to the level of a grand touring vehicle from that manufacturer, and so on. Only in the highest stage does the limitation correspond to the vehicle's actual dynamic potential.

[0044] If the driver remains within the speed limit, the function according to the invention does not intervene. Only if the driver risks exceeding the driving dynamics level of the scaled-down vehicle is their speed limited. The data calculated by the racetrack assistant, such as the ideal line and optimal speed profile, or a lap-time-optimized speed progression, can be visualized for the driver to analyze their driving technique, even during a drive or between drives.

[0045] In principle, a wide variety of comparisons can be made between the laps driven by the driver and those driven by other drivers, other vehicles, other environmental conditions, or model-based idealized drives.

[0046] For example, a comparison is possible using ideal environmental conditions, a top-performing vehicle, and a top-performing driver. This involves determining the theoretically fastest speed profile or lap time along an ideal trajectory calculated using computer-aided optimization. This is achieved, for instance, by modeling or simulating the best coefficient of friction ever determined on the specific racetrack, a theoretically fastest available vehicle, and an ideal trajectory over the track—that is, under ideal conditions. In this case, a current driver with their vehicle and their actual trajectory is presented with a comparison of what is theoretically possible under all idealized assumptions over this racetrack.

[0047] Alternatively, a comparison can be made using current or real-world environmental conditions, the best vehicle, and the best driver. This involves determining the theoretically fastest speed profile or lap time along an ideal trajectory calculated using computer-aided optimization. The current coefficient of friction on the racetrack can be determined directly from previous runs of the current or a comparable vehicle, either directly or under comparable environmental conditions. Using the current environmental conditions and the theoretically fastest available vehicle, a model or simulation is then created along an ideal trajectory on the racetrack, driven by the best driver.

[0048] Furthermore, a comparison is made for a current driver with their vehicle and driven trajectory. In other words, a comparison is made of what is theoretically possible under real-world conditions with the best vehicle and driver on an ideal trajectory. For this purpose, the theoretically fastest speed profile or the theoretically fastest lap time is determined along an ideal trajectory calculated using computer-aided optimization.

[0049] Furthermore, the best coefficient of friction ever determined on the specific racetrack, a vehicle comparable to the current one driven by the best driver on an ideal trajectory over the racetrack, is modeled or simulated. This means that the current driver, his vehicle, and a trajectory are compared to determine what is theoretically possible under optimal environmental conditions with his (intact) vehicle and best driver on an ideal trajectory.

[0050] By comparing current or real-world environmental conditions, a current vehicle, and a best driver, the theoretically fastest speed profile or lap time is determined along an ideal trajectory calculated using computer-aided optimization. The current coefficient of friction on the racetrack can be determined directly from previous runs of the current or a comparable vehicle, either under comparable environmental conditions. Using the current environmental conditions and a vehicle comparable to the current or real-world vehicle (driven by a best driver), an ideal trajectory on the racetrack is modeled or simulated.A current driver, with their vehicle and driven trajectory, can compare what is theoretically possible under real-world conditions with their fully functional vehicle and the best driver on an ideal trajectory. This means that the differences arise solely from the driver's abilities.

[0051] By comparing current or real-world environmental conditions, a current or real-world vehicle, and a best driver on a real-world trajectory, the theoretically fastest speed profile or fastest lap time along the trajectory driven by the driver is determined. The current coefficient of friction on the racetrack can be determined directly from previous runs of the current or a comparable vehicle under comparable environmental conditions. Using the current environmental conditions and the best driver and the current or real-world vehicle, a model or simulation is created on a trajectory actually driven by the driver on the racetrack.It follows that a current driver with his vehicle and his driven trajectory has a comparison here of what would be possible at the same time and in the same vehicle with a perfect driver on his driven trajectory.

[0052] The driver can perform the comparison online and / or offline. The online version offers several options for displaying the differences. For example, an augmented view of the comparison vehicle and driver is displayed along the ideal and / or actual trajectory. Furthermore, differences in parameters such as speed, acceleration, and / or position over the route can be shown. Alternatively, the data can be visualized offline and, optionally, analyzed with additional sensor information, such as recorded driver inputs, to identify optimization and / or improvement potential.

[0053] In the event of the use or activation of brake assist and the exceeding of the last possible braking point in the current section of the road, it is particularly advantageous to initiate automated braking with optimal brake pressure and its subsequent progression. The driver can regain control at any time within the permissible limits by operating the pedals. Even if the driver begins braking before the last possible braking point, but the required braking force is insufficient at the braking point, the brake assist takes over.

[0054] Even if the driver exceeds the speed limit at the exit of a curve by accelerating too early and / or too hard, the assistant limits the speed. Instead of, or in addition to, braking interventions, active interventions in the drive torque occur, for example by limiting the accelerator pedal input or ultimately by limiting the speed.

[0055] To avoid unexpectedly surprising and ultimately disempowering the driver with automatic braking intervention, it is possible to visually, haptically, and / or audibly display the distance and / or time until automatic braking intervention, based on the current speed and the permissible speed profile. If the driver brakes in time but insufficiently, the predicted brake pressure or braking force / braking distance from the last possible braking point can optionally be displayed visually, haptically, and / or audibly. Haptic feedback is provided, for example, via the brake pedal.

[0056] The intensity of the acoustic and / or haptic feedback correlates, for example, with the proximity to the last possible braking point. Similarly, the visual feedback correlates with its color and / or intensity. If steering assist systems are used or activated, it is optional to influence the steering so that it follows the currently predicted safe trajectory and, optionally, guides the vehicle onto the ideal trajectory.

[0057] After a braking phase, engine braking phase, etc., the driver typically re-engages the accelerator pedal, restarting the drive system. For example, in addition to displaying an ideal speed, the system automatically accelerates for a specific time and / or distance, and, to guide the driver, optionally depresses the accelerator pedal accordingly.

[0058] Optionally or alternatively, the time and / or distance to the resumption point after the braking or deceleration phase, and optionally the required accelerator pedal position, are displayed visually, haptically, and / or audibly. Haptic feedback could, for example, be provided via the accelerator pedal.

[0059] Furthermore, it is possible to actively limit the accelerator pedal position to prevent the vehicle from skidding, experiencing dynamic instabilities, or deviating from the ideal or safe trajectory. System interventions can be displayed to analyze the driver's driving on the circuit, providing the driver with information on where time or safety reserves were not utilized and where the assistance systems ensured their safety.

[0060] Ultimately, it is advisable that the described assistance functions can be configured, activated, or deactivated by the driver. Furthermore, activation for specific route sections in advance is also possible, in order to optionally limit manual training sessions to specific driving and route situations. In principle, the safety-relevant aspects of the described approach can also be applied to dangerous sections of road within the EU or worldwide, for example, at motorway exits or hairpin bends, based, for instance, on accident statistics. These can be analyzed accordingly and integrated as a service into, for example, a navigation system, so that the vehicle can brake accordingly when necessary.

[0061] Fig. Figure 4 shows a block diagram of a control unit 104 according to an embodiment used for a vehicle such as that found in Fig. 1 described. The control unit 104 is designed to control and / or execute a procedure for operating the vehicle, such as that described in Fig. 3. For this purpose, the control unit 104 has a determination unit 400, a comparison unit 402, and a control unit 404. The determination unit 400 is configured to determine a speed profile 406 for at least one segment of a vehicle journey using at least one vehicle information 408, at least one environmental information 410, and / or at least one driver information 412 from the driver of the vehicle. The comparison unit 402 is configured to compare the speed profile 406 with reference data 414, which represent a target speed profile for the journey segment and / or at least one limit value, in order to obtain a comparison result 416 that represents a deviation between the speed profile 406 and the reference data 414.The control unit 404 is designed to control a device 102 for braking the vehicle using the comparison result 416.

[0062] In addition, the determination unit 400 is configured according to one embodiment to determine an actual trajectory 417 for the vehicle using the vehicle information 408, the environmental information 410, and / or the driver information 412. The comparison unit 402 is therefore configured to compare the actual trajectory 417 with further reference data 419, which represent a target trajectory, in order to obtain a further comparison result 421, which represents a deviation between the actual trajectory 417 and the target trajectory. For example, the reference data 414 and the further reference data 419 are read in via an interface 106. The control unit 404 is configured to control the device 102 using the comparison result 421 in order to approximate the actual trajectory 417 to the target trajectory.

[0063] Optionally, the determination unit 400 is configured according to one embodiment to determine a current speed profile 406' for at least one further driving segment of the journey using at least one further vehicle information 408', at least one further environmental information 410', and / or at least one further driver information 412'. The comparison unit 402 is therefore configured to compare the current speed profile 406' with the reference data 414 in order to obtain a current comparison result 416' that represents a deviation between the current speed profile 406' and the reference data 414. The control unit 404 is configured to control the vehicle's device 102 using the current comparison result 416'.

[0064] According to this embodiment, the control unit 104 additionally has an output unit 418 configured to output a display signal 420 for showing the speed profile 406 and / or the reference data 414 via an interface to a display device 422 of the vehicle. Optionally, the output unit 418 is also configured to output a warning signal 424 to the driver when at least one limit value has been reached.

[0065] Fig. Figure 5 shows a velocity-distance diagram 500 of a velocity profile according to an exemplary embodiment, as is found, for example, in Fig. The method described in section 3 is used to determine the speed. The x-axis 502 of diagram 500 represents the path or the respective position over the racetrack, and the y-axis 504 represents the vehicle's speed over the racetrack. One curve 505 of the curves 506 shown in diagram 500 represents the reference data representing an ideal speed profile. According to this embodiment, the other curves 506 each represent a separate speed profile for each lap.

[0066] In other words, this embodiment provides an exemplary representation of the speed profile of a real driver over four laps (R1, R2, R3, R4) compared to a maximum possible target speed (v_target).

[0067] In the areas surrounded by a box, a difference in speed between the individual laps can be seen.

[0068] Fig. Figure 6 shows a representation of a further developed Kamm circle 608 for the vehicle, or rather the vehicle model. In the further developed Kamm circle 608, the longitudinal and lateral accelerations are used instead of the longitudinal and lateral forces. max , aquer max as well as the speed v for the respective vehicle as a third dimension.

[0069] From this, it can be derived, for example, what longitudinal acceleration, such as deceleration during braking, is possible at a given lateral acceleration and speed. It is generated based on vehicle parameters such as mass, drag coefficient, coefficient of friction, etc. Some of these parameters, such as the coefficient of friction or friction coefficients, are determined in driving tests using measurement data or sensor data and vehicle parameters. It is possible to determine these parameters using previously driven laps, for example, online. Thus, with racing drivers, wheel slip will very likely occur even in the first lap or during practice under comparable environmental conditions, since the total force resulting from longitudinal and lateral forces exceeds the available maximum frictional force.

[0070] In cases of differing road surfaces and environmental conditions, such as varying coefficients of friction across the track, the respective further developed Kamm circle 608 is assigned to the track sections where slippage occurred, with respect to the vehicle model. This then applies to the further section of the track until the next further developed Kamm circle 608 is encountered.

[0071] For example, friction coefficient maps can be used if the multiple race cars are networked with the provider of such a map. According to this embodiment, the method is also feasible if the ego car, for example, is alone or not networked with a friction coefficient map during a high-speed test and / or private race, provided that friction coefficients can be derived from the current wheel slip. In addition to information regarding the trajectory and speed profile, braking points and braking distances play an important role with regard to fast lap times and, in particular, driver safety. According to this embodiment, the ideal braking action over the racetrack is therefore determined using the above-mentioned modeling or simulation variants, in addition to the trajectory and speed profile.This means that the braking point is determined with the corresponding ideal braking force and / or brake pedal travel and / or brake pressure and their further course.

Claims

[1] Method (300) for operating a vehicle (100), wherein the method (300) comprises the following steps: Determine (302) a speed profile (406) for at least one segment (206) of a journey (200) of the vehicle (100) using at least one vehicle information (408), at least one environment information (410) and / or at least one driver information (412) of a driver of the vehicle (100); Comparing (304) the speed profile (406) with reference data (414) representing a target speed profile for the driving segment (206) and / or at least one limit value, in order to obtain a comparison result (416) representing a deviation between the speed profile (406) and the reference data (414); Controlling (306) a device (102) for braking the vehicle (100) using the comparison result (416). [2] Method (300) according to claim 1, wherein in step (302) of determining, an actual trajectory (417) for the vehicle (100) is additionally determined using the vehicle information (408), the environment information (410) and / or the driver information (412), wherein in step (304) of comparing, the actual trajectory (417) is compared with further reference data (419) representing a target trajectory in order to obtain a further comparison result (421) representing a deviation between the actual trajectory (417) and the target trajectory, wherein in step (306) of controlling, the device (102) is controlled using the further comparison result (421) to approximate the actual trajectory (417) to the target trajectory. [3] Method (300) according to one of the preceding claims, wherein in step (304) of comparing the at least one limit value is obtained which represents a real achievable maximum speed of the vehicle (100) for the driving section (206) and / or a braking force required to decelerate the vehicle (100) at the latest possible braking time as a function of the maximum speed for the driving section (206). [4] Method (300) according to one of the preceding claims, wherein in step (306) of determining the velocity profile (406) is determined using a modified or further developed Kamm circle (608). [5] Method (300) according to one of the preceding claims, wherein in a repeated step (302) of determining, a current speed profile (406') for at least one further driving segment (208) of the journey (200) is determined using at least one further vehicle information (408'), at least one further environmental information (410') and / or at least one further driver information (412') of the driver, wherein in a repeated step (304) of comparing, the current speed profile (406') is compared with the reference data (414) to obtain a current comparison result (416') that represents a deviation between the current speed profile (406') and the reference data (414), and wherein in a repeated step (306) of controlling, the device (102) of the vehicle (100) is controlled using the current comparison result (416'). [6] Method (300) according to one of the preceding claims, comprising a step (310) of outputting a display signal (420) to display the speed profile (406) and / or the reference data (414) via an interface to a display device (422) of the vehicle (100). [7] Method (300) according to claim 6, wherein in step (310) of output a warning signal (424) is output to the driver when at least one limit value has been reached. [8] Method (300) according to one of the preceding claims, comprising a step (308) of locating the vehicle (100) on the route (201) using GPS to generate the vehicle information (408) for determining the speed profile (406). [9] Method (300) according to one of the preceding claims, wherein the reference data (414) are read in via an interface (106) to a vehicle-external device (108). [10] Method (300) according to one of the preceding claims, wherein at least during the steering step (306) no automatic intervention is made in the steering of the vehicle (100). [11] Control unit (104) configured to perform and / or control the steps (302, 304, 306, 308, 310) of the method (300) according to any of the preceding claims in corresponding units (400, 402, 404, 418). [12] Computer program configured to execute and / or control the steps (302, 304, 306, 308, 310) of the method (300) according to any one of claims 1 to 10. [13] Machine-readable storage medium on which the computer program according to claim 12 is stored. [14] Vehicle (100) with the following features: a device (102) for braking the vehicle; and a control unit (104) according to claim 11, which is coupled to the device (102).

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