Method for determining a comfort value for a motor vehicle in operation

Abstract

The invention relates to a method for determining a comfort value (KPI) for a motor vehicle (10) in operation. A cost function (CF) is calculated for the comfort value (KPI) as a function of the time (t) that has elapsed while the motor vehicle (10) is in operation. In this process, measured longitudinal acceleration (ax), transverse acceleration (ay) and predefined weighting factors (w ax ,w ay The first time value (Z1) and / or the second time value (Z2) are retrieved from a navigation unit (15). The calculated cost function (CF) is normalized with the aid of the first and / or second time value (Z1, Z2) of the navigation unit (15) in order to determine a comfort value (KPI) for the motor vehicle (10) in operation.

Description

Technical Field

[0001] The invention relates to a method for determining a comfort value for a motor vehicle in operation. The invention also relates to a motor vehicle having an acceleration sensor, a primary sensor and a clock for determining a comfort value. Background Art

[0002] In modern motor vehicles, autonomous or partially autonomous control of the motor vehicle is becoming more and more prominent. In addition to the complex technical requirements for realizing autonomous vehicles, there is also a demand for additional customer-specific specifications. In many cases, in addition to safe driving of autonomous vehicles, a corresponding degree of driving comfort is also desired. Corresponding expectations for autonomous motor vehicles can also be drawn in terms of driving style.

[0003] Motion sickness can occur in particular in semi-autonomous or autonomous motor vehicles. This motion sickness can in principle be compared to seasickness. Therefore, when developing autonomous motor vehicles or such systems, there is a need to be able to objectively compare different driving styles with one another. In particular, it should be possible to objectively compare different autonomous controllers with one another. The publication "Optimizing Passenger Comfort in the Cost Function of Trajectory Planning" by Jan Elsner from the Technical University of Munich deals with cost functions related to comfort aspects. However, no objective comfort values ​​(with which different driving controls or driving styles can be compared with one another) are mentioned.

[0004] Publication DE 10 201 5 209 575 A1 describes a navigation device and a navigation method. The navigation device comprises an interface for obtaining point evaluations of a plurality of comfort factors for at least one driving route from at least one user in a vehicle. Based on the received point evaluations, a net comfort value for at least one driving route is calculated. Based on the net comfort value, a controller suggests one or more driving routes to a driving destination.

[0005] The present invention is based on the following recognition: In addition to the expectation of high driving comfort, there are also different requirements or ideas in terms of driving style. For example, a young and energetic person in his early twenties has a different driving behavior from an elderly person who is already at retirement age. For example, several driving styles can be divided into categories such as comfort, efficiency, agility or sportiness. Depending on the driver, different preferences may arise in terms of driving style. When developing autonomous motor vehicles or partially autonomous motor vehicles, the corresponding control of the motor vehicle should be increasingly undertaken by the corresponding electronic control device. In addition to the reliable operation of the motor vehicle, it is also important to achieve the corresponding driving style. However, for this purpose, it must be possible to objectively compare different driving modes or control systems for autonomous motor vehicles. Such a solution is still unknown. Summary of the invention

[0006] The technical problem to be solved by the present invention is to create or provide an objective comparison variable, by means of which different driving modes in a running motor vehicle can be better compared with each other. The different driving modes can involve different control units and / or different persons who guide or operate the motor vehicle. Thus, for example, a first manufacturer or developer of an autonomous motor vehicle control unit can provide a corresponding control unit. The same applies to a second manufacturer. Although the two control units can achieve reliable partially autonomous or autonomous driving, differences may arise in terms of driving comfort or driving style.

[0007] The present invention proposes a method to be able to compare these different driving styles better and more objectively. The approach is preferably for different autonomous or partially autonomous control systems, but can also be extended to different human driving styles.

[0008] The technical problem is solved by a method for determining a comfort value for a motor vehicle in operation, comprising the following method steps:

[0009] a) calculating a cost function for the comfort value based on the time elapsed during the operation of the motor vehicle, the measured longitudinal acceleration, the measured transverse acceleration and a predefined weighting factor for the longitudinal acceleration and the transverse acceleration,

[0010] b) taking into account the current traffic volume provided by the navigation unit, calling up a first time value relating to an estimated travel time of the motor vehicle and a second time value relating to an expected actual travel time of the motor vehicle,

[0011] c) Normalizing the calculated cost function using the first and / or second time value of the navigation unit in order to determine a comfort value for the operating motor vehicle.

[0012] A first aspect of the invention relates to a method for determining a comfort value for a motor vehicle in operation. In particular, the comfort value can be used to evaluate the driving style. The method may comprise the following steps. First, a cost function for the comfort value is calculated based on the time elapsed during the operation of the motor vehicle, the measured longitudinal acceleration, the measured lateral acceleration and based on a weighting factor based on the longitudinal acceleration and the lateral acceleration. The weighting factor can influence the cost function and is related to the longitudinal acceleration and / or the lateral acceleration. Preferably, the weighting factor is pre-given. In this context, the term "calculation" may mean determining, analyzing, evaluating and / or estimating. In particular, the elapsed time is measured during the operation of the motor vehicle. This is preferably applicable to the operation or driving of the motor vehicle in road traffic. The elapsed time may in particular include the moment corresponding to the start of the operation of the motor vehicle as the starting time point.

[0013] The term "operation of a motor vehicle" includes in particular all actions and maneuvers of a motor vehicle during travel or during a route in road traffic. Thus, for example, a possible short-term deactivation of the engine of a motor vehicle due to an automatic start-stop system is also included in the time that has elapsed while the motor vehicle is in operation. Thus, the time that has elapsed by the motor vehicle may include a start time and an end time. The start time relates in particular to the start of the motor vehicle for a route or travel, while the end time represents in particular the end of the route or travel of the motor vehicle.

[0014] In another step, under the condition of considering the current traffic volume, the navigation unit calls up the first time value of the estimated driving time of the motor vehicle and the second time value of the estimated actual driving time of the motor vehicle. The first and / or second time values ​​are preferably provided and / or determined by the navigation unit. The navigation unit can be constructed as an external navigation unit. The external navigation unit can be designed as real-time navigation. The estimated driving time can be referred to as the first time value or the first driving time, and the estimated actual driving time can be referred to as the second driving time or the second time value. Usually, due to considering the current traffic volume, the first driving time and the second driving time are different. The second driving time is preferably provided by the external navigation unit. For this purpose, the control unit can establish a data connection with the external navigation unit by means of an interface and call the first and / or second time value. The first time value especially represents the estimated driving time of the motor vehicle along a predetermined route. The estimated travel time (first time value) especially takes into account the route direction, the predetermined speed limit and / or the route parameters predetermined independently of traffic, such as a crossroads or a zebra crossing. Based on these parameters, the estimated travel time for the driving or route of the motor vehicle can be given.

[0015] The second time value is particularly related to the estimated realistic driving time of the motor vehicle. The current traffic conditions or the current traffic volume are particularly taken into account in the second time value. Current traffic reports, such as congestion or road blockages, can also be included in the second time value. These two time values ​​are preferably called by the navigation unit. The navigation unit can be a device located inside the motor vehicle and can establish a data connection to the navigation server. For this purpose, a corresponding data connection with the navigation server can be established through the interface of the motor vehicle. From there, the two time values ​​can be obtained or called. The (external) navigation unit can, for example, realize real-time navigation with the help of an online map service provider. Here, it is not important to specify the specific design of the navigation unit or even the corresponding provider, but the first time value and / or the second time value are provided by the navigation unit and can be called. For this reason, it is preferably provided that the motor vehicle has a corresponding interface, so that a data connection with the navigation server can be established.

[0016] In a further step, the calculated cost function is normalized (or referred to as standardized) with the aid of the first and / or second time value of the navigation unit in order to determine a comfort value for the motor vehicle in operation. Normalization can in particular mean that the cost function is associated with the first and / or second time value. Specifically, this can mean that the value of the cost function is divided by the first or second time value. The calculated cost function can in particular be a numerical value. The numerical value can be a quotient, in which the numerator contains the value of the cost function and the denominator contains one of the two time values. The same applies to the first and / or second time value. The cost function as well as the time value can have the unit second. Therefore, normalizing the calculated cost function with the aid of the time value preferably results in dimensionless units.

[0017] Based on this normalization, objective comfort values ​​can be provided for the motor vehicles being operated. Therefore, multiple trips of the same motor vehicle can be compared more objectively. Therefore, in order to compare the driving styles of different driving modes, for example, non-faulty delays can be better calculated, such as speed limits suddenly implemented on highways, unexpectedly longer red light phases at traffic lights, etc. For example, if the second motor vehicle only drives the same section of road at half the speed of the first motor vehicle, this will first lead to a correspondingly worse or higher comfort value. This is especially because a higher value is obtained in the cost function due to the slower speed. In this case, the cost function and therefore the comfort value will be significantly different for the two motor vehicles only due to the more comfortable driving mode. However, such different traffic scenarios do not necessarily have objective comparability. For this reason, the method proposes to normalize the calculated cost function by means of the first and / or second time values. In this case, the longitudinal acceleration and the lateral acceleration will be retained in the cost function as influencing variables. For example, a busy driving mode (which can be characterized by frequent braking and re-acceleration) will lead to a corresponding increase in the cost function. If normalization is neglected, this driving style may be obscured by a longer time, which may be caused by correspondingly slower driving. Therefore, by means of normalization of the cost function, in particular factors that are not due to a driving style can be calculated. The comfort value proposed here therefore contains in particular influencing factors that are mainly attributable to the driving style and / or driving behavior. In this way, better comparability of different driving styles or driving styles can be achieved.

[0018] An additional or alternative refinement provides that a cost function is associated with the first and / or second time value in order to determine the comfort value. In particular, the calculated cost function is divided by the first and / or second time value. This is in particular a normalization step. In this case, a quotient can be formed, wherein the calculated cost function is used in the numerator and the first or second time value is used in the denominator. The advantages already mentioned apply appropriately to this refinement.

[0019] Additionally or alternatively, the cost function may be based on the longitudinal jerk The weighting factors are preferably predetermined and / or can be predetermined by the manufacturer. The longitudinal acceleration, the lateral acceleration, the longitudinal jerk and the lateral jerk can each have its own weighting factor. In this improved scheme, in addition to the longitudinal acceleration and the lateral acceleration, uneven acceleration can also be considered, that is, in the form of jerk (or bump, impact). Jerk is especially the time derivative of acceleration or the third derivative with respect to time. In this case, a busy (or hurried) driving mode will be more reflected in the cost function. Therefore, a more accurate and precise analysis of the driving style can be achieved, and therefore better comparability can be achieved.

[0020] Additionally or alternatively, it can be provided that the cost function relates to a section with a predetermined minimum length. Preferably, the section has a length of at least 10 km. Thus, interfering effects over short distances can be better eliminated. Thus, the reliability of the comfort value in terms of its meaning can be increased.

[0021] Additionally or alternatively, it can be provided that the calculation of the cost function, the calling and / or the normalization of the two time values ​​are performed during the operation of the motor vehicle. Therefore, the method for determining the comfort value is preferably performed during driving or during the operation of the motor vehicle along the route. In particular, the determined comfort value can be stored in a storage unit of the motor vehicle and / or in an external storage unit. Here, additionally, the associated timestamp with the comfort value can be stored. The timestamp can include a time start time point and an end time point representing the time of the motor vehicle passing. Therefore, the driving style can be evaluated during driving or the route. The comfort value can be displayed on a display in the motor vehicle. Therefore, feedback on the driving style and / or the comfort value can be performed during the operation of the motor vehicle.

[0022] An advantageous improvement scheme additionally or alternatively provides that a plurality of comfort values ​​are determined by multiple calculations, calling the first and / or second time values ​​and / or normalization. It is also possible to call the time values ​​multiple times and / or perform the corresponding normalization multiple times. The plurality of comfort values ​​are preferably compared with each other in order to evaluate the driving style, and based on the comparison, an autonomous or partially autonomous control for the motor vehicle is provided. The improvement scheme is particularly meaningful for evaluating different control units for autonomous or partially autonomous motor vehicles. Therefore, for example, the motor vehicle can move autonomously or partially autonomously along a predetermined route multiple times. Here, different control units that control the motor vehicle can be used respectively. Therefore, a corresponding comfort value can be assigned to each control unit. The plurality of comfort values ​​can therefore be compared with each other. Therefore, for example, different control units from different manufacturers can be objectively compared with each other. The corresponding comfort value can represent the corresponding driving style in particular. According to the preset, a corresponding control unit or a corresponding comfort value for the autonomous or partially autonomous control of the motor vehicle can be provided. The "providing" can include or mean the selection of comfort values ​​and their application for the autonomous or partially autonomous control of the motor vehicle. In this improvement scheme, the corresponding comfort value is preferably associated with the associated controller or the associated control unit. Therefore, a corresponding control unit or a corresponding controller may be provided and / or selected based on the plurality of comfort values.

[0023] Furthermore, it can be provided additionally or alternatively that the comfort values ​​are classified according to a plurality of pre-given driving modes and only the comfort values ​​of the same driving mode are compared with each other. Different driving modes can be divided into comfortable, efficient, agile and / or sporty categories, for example. Grading between the mentioned possibilities is also conceivable. A sporty driving style can have different comfort values ​​than a comfortable driving style. This can be shown in particular in terms of the individual components of the comfort value. A sporty driving style includes in particular a higher share in longitudinal and lateral acceleration. The same applies to longitudinal jerkiness and / or lateral jerkiness. Therefore, a more targeted comparison can be made.

[0024] Additionally or alternatively, it can be provided that the weighting factors are defined as a function of the respective driving mode. If, for example, a sporty driving style is preferred, the respective weighting factors can be reduced. In this case, the calculation cost function does not necessarily lead to an automatically worsened comfort value. In this way, the desired driving style of the operator can be taken into account in the autonomous or partially autonomous control of the motor vehicle. The weighting factors can in principle be individually set, but are preferably predefined by the manufacturer.

[0025] Additionally or alternatively, a minimum comfort value is selected from a plurality of comfort values ​​and / or provided for autonomous or partially autonomous control of the motor vehicle. This refinement corresponds to the most common application cases. A comfortable and efficient driving of a motor vehicle is generally desired. Such driving values ​​are most likely to be represented by the smallest possible comfort value. Thus, a good driving style can be found for most customer requirements.

[0026] Additionally or alternatively, the cost function can be calculated based on the driving speed of the motor vehicle, the GPS coordinates and / or the length of the route traveled. The driving time as the elapsed time is particularly taken into account in the cost function or the cost function. In the elapsed time, the speed can be taken into account. In particular, the cost function can be normalized in terms of the length of the route traveled. In this case, the calculated cost function can be divided by the length of the route traveled. With the help of corresponding terms and weighting factors for the driving speed, the speed of the motor vehicle can be taken into account when calculating the cost function. This can also be applied to the GPS coordinates. The GPS coordinates can be taken into account in the cost function in addition. Therefore, a more detailed cost function can be realized and therefore a more sophisticated comparison of the corresponding driving style can be realized.

[0027] A second aspect of the invention relates to a motor vehicle that can implement a corresponding method for determining a comfort value. The motor vehicle preferably has an acceleration sensor for measuring longitudinal acceleration and lateral acceleration. Preferably, it also includes a jerk sensor for measuring longitudinal jerk and lateral jerk. The jerk sensor can be configured in particular as a modified acceleration sensor and / or inertial sensor. The modified acceleration sensor and / or inertial sensor can be designed to detect acceleration and convert acceleration into jerk. This can be achieved, for example, by forming a derivative of the acceleration with respect to time.

[0028] The motor vehicle preferably has a clock, a stopwatch or a similar sensor device in order to measure the time that has passed while the motor vehicle is in motion. The motor vehicle also preferably has a control unit that is designed to calculate a cost function for the comfort value based on the time that has passed while the motor vehicle is in motion, based on the longitudinal acceleration, the transverse acceleration and a predefined weighting factor for the longitudinal acceleration and the transverse acceleration.

[0029] The acceleration sensor can be considered as a first sensor and the jerk sensor can be considered as a second sensor. The first sensor can measure longitudinal and lateral acceleration. The second sensor can measure longitudinal and lateral pressure. To this end, the second sensor can transform the measured acceleration into jerk, for example, by means of a time derivative of the measured acceleration. In particular, the first sensor and the second sensor can be configured as a common sensor or sensor unit. In this case, the sensor unit can detect or measure acceleration and jerk.

[0030] The motor vehicle preferably has a control unit. The control unit may have a processor device, which is configured to execute an embodiment of the method. For this purpose, the processor device may have at least one microprocessor, at least one microcontroller, at least one FPGA (field programmable gate array), at least one DSP (digital signal processor) and / or a neural network. In addition, the processor device may have a program code, which is configured to execute an embodiment of the method when implemented by the processor device. The program code may be stored in a data memory of the processor device. The control unit may include an internal or external storage unit. The external storage unit may be designed as a cloud unit.

[0031] The calculation of the cost function can be represented in particular by means of the following formula.

[0032]

[0033] In Formula 1, “time” represents the elapsed time, w ax 、w ay They represent the weighting factors of longitudinal acceleration and lateral acceleration, w jx and w jy The variables x and y denote in particular position coordinates in a Cartesian coordinate system. ax preferably denotes the acceleration in the x direction, the direction of travel, and ay preferably denotes the lateral acceleration perpendicular to the direction of travel in the plane of the roadway. The same applies to the jerk in the x direction, which is denoted by jx, and the jerk jy, which is denoted by jy. Instead of Cartesian coordinates, other coordinate systems can also be used.

[0034] The comfort value can be determined by the following formula.

[0035] or

[0036] Formula 2

[0037] KPI represents the comfort value in Formula 2, and J is known from Formula 1. Z1 and Z2 represent the first time value and the second time value, respectively. Formula 2 specifically represents the normalization of the cost function.

[0038] The control unit is also designed or arranged to call up a first time value related to an estimated travel time of the motor vehicle and a second time value related to an estimated actual travel time of the motor vehicle, wherein the estimated actual travel time takes into account the current traffic volume or the current traffic situation. The current traffic situation or the current traffic situation is provided in particular by the navigation unit. Therefore, the two time values ​​are preferably called up by the navigation unit. In addition, the control unit can normalize the calculated cost function with the aid of the first and / or second time value of the navigation unit in order to determine a comfort value for the motor vehicle to be operated.

[0039] Features, advantages and examples presented in conjunction with the method according to the first aspect of the invention apply correspondingly to the motor vehicle according to the second aspect of the invention and vice versa. Device features may be understood as method features and method features may likewise be interpreted as device features.

[0040] The advantages mentioned in the above-mentioned improvements and embodiments can be transferred to the motor vehicle in a meaningful manner. The motor vehicle can also have an interface. A connection to a data server or a server of a navigation unit can be established using the interface. The navigation unit can be arranged externally, that is, outside the motor vehicle. Thus, the first and / or second time value can be called up by an external navigation server. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The invention will now be explained in more detail with the aid of exemplary drawings. It should be noted that the drawings only show preferred embodiments or improvements and do not limit the invention. In the drawings, functionally identical elements are each provided with the same reference numerals. In the drawings:

[0042] Figure 1 An exemplary diagram showing a motor vehicle in a coordinate system;

[0043] Figure 2 An exemplary diagram is shown for determining or calculating a comfort value;

[0044] Figure 3 showing an exemplary travel route of a motor vehicle;

[0045] Figure 4 shows a comparison of the calculated comfort values ​​with and without normalization;

[0046] Figure 5 Another example of a determined comfort value is shown. DETAILED DESCRIPTION

[0047] The embodiments explained below are preferred embodiments of the present invention. In the embodiments, the components described are respectively individual, mutually independently considered features of the present invention, which also improve the present invention independently of each other, and are therefore also considered as components of the present invention individually or in combinations different from the combinations shown. In addition, the described embodiments can also be supplemented by other already described features of the present invention.

[0048] exist Figure 1 , a motor vehicle 10 with a coordinate system x, y and z is shown. The x-axis in particular indicates the direction of travel of the motor vehicle 10, the y-direction indicates the transverse direction of the motor vehicle 10 and the z-direction indicates the vertical direction of the motor vehicle 10. In most cases, the z-direction of the motor vehicle 10 has no influence. As long as the motor vehicle 10 is not designed as a flying taxi, the z-component can be ignored. The invention preferably relates to a land-based motor vehicle 10 moving in the xy plane. In principle, however, the invention can also be extended to flyable vehicles, such as flying taxis.

[0049] The motor vehicle 10 may have a clock 11, an acceleration sensor 12, a jerk sensor 13, a control unit A, and an interface 14. The control unit A may be designed for a specific driving mode. The motor vehicle 10 may also have an internal navigation device 16. The internal navigation device 16 may be integrated into the onboard electronics or temporarily fixed on the windshield as a mobile navigation device 16. The clock 11 is used to measure the time t that has passed when the motor vehicle 10 is running. This is especially the difference between the starting time point and the ending time point. These two time points especially represent the beginning and end of the driving or route. The acceleration sensor 12 is mainly used to measure the longitudinal acceleration ax or the lateral acceleration ay. In particular, in order to measure the longitudinal acceleration ax, there may be an acceleration sensor of its own. Accordingly, the lateral acceleration ay can be measured by means of another additional separate acceleration sensor. The longitudinal acceleration ax and the lateral acceleration ay can preferably be measured simultaneously by means of a multi-dimensional acceleration sensor. The multi-dimensional sensor can be configured to measure acceleration and jerk simultaneously. In particular, the multi-dimensional sensor can detect or measure jerk and acceleration in different spatial directions respectively.

[0050] The longitudinal jerk jx and / or the lateral jerk jy can be detected by means of the jerk sensor 13. The longitudinal jerk Jx or the lateral jerk Jy can be measured by one or more jerk sensors 13. The one or more jerk sensors 13 can be inertial sensors 13 or modified acceleration sensors. In contrast, a "normal" acceleration sensor 12 can detect and / or measure the longitudinal acceleration ax and the lateral acceleration ay. It is also possible that the acceleration sensor 12 and the jerk sensor 13 are implemented by a common sensor unit.

[0051] For the longitudinal jerk jx and the transverse jerk jy, a separate jerk sensor 13 can be provided. By means of the interface 14, the motor vehicle 10 can establish a connection with an external navigation unit 15. The external navigation unit 15 is preferably capable of real-time navigation. The external navigation unit 15 can have an external server. Via the interface 14, the control unit A can establish a data connection with the server of the external navigation unit 15 and call up the first time value Z1 and / or the second time value Z2.

[0052] exist Figure 2 The schematic process of the present invention is exemplarily shown in FIG. Figure 2 Different diagrams are shown in the left area of ​​. These diagrams can, for example, represent the longitudinal acceleration ax and the lateral acceleration ay. The same applies to the longitudinal jerk jx and the lateral jerk jy. Likewise, the time t can be introduced into the calculation of the cost function CF. In this respect, the reference symbol t and the term "time" in formula 1 can mean the same. The cost function CF can contain different terms, which are characterized by corresponding weighting factors Wax, Way, Wjx and Wjy.

[0053] exist Figure 2 The middle of shows an exemplary distribution of weighting factors. Usually, the weighting factors are predetermined. However, if it is desired to make a customer-specific adjustment to the cost function CF, the weighting factors can be adjusted individually. Through the cost function CF, the input data ax, ay, jx and jy and the time t that has passed can determine or calculate the comfort value KPI. The present invention preferably provides here that a new normalized comfort value KPI is calculated. For this purpose, the first time value Z1 and / or the second time value Z2 are called from the internal navigation unit 16 or the external navigation unit 15. The internal navigation unit 16 can be a smart phone, a PDA and / or a tablet computer. The first time value Z1 especially represents the expected duration of the driving route or the expected driving time or travel time of the motor vehicle 10. However, in the case of the first time value Z1, the current traffic conditions are usually not taken into account. Usually, road obstructions or congestion are not taken into account in the case of the first time value Z1. On the contrary, the second time value Z2 preferably takes into account the current traffic flow or the current traffic report. Therefore, the second time value Z2 corresponds to the expected actual driving time, driving duration or duration of the route of the motor vehicle 10. The second time value Z2 can be regarded as the actual actual time value. In most cases, it is preferred to perform the normalization using the second time value Z2.

[0054] The cost function CF can be called a cost function. The weighting factor w is determined by means of the cost function and the empirical formula ax 、w ay 、w jx and w jy, comfort-related measured variables (such as longitudinal acceleration ax, lateral acceleration ay, longitudinal jerk jx and lateral jerk jy) can calculate a comfort value KPI. The comfort value KPI is preferably normalized and can be output accordingly on a display. The comfort value KPI can be normalized to a driving section or a section distance. In order to calculate traffic influences and route-specific characteristics, such as roundabouts, intersections, traffic lights, etc., real-time navigation data of the navigation unit 15 are preferably taken into account when determining or calculating the comfort value KPI. This is achieved in particular by normalization. With the help of this normalized comfort value KPI, the driving comfort or driving style on different routes in road traffic can be better evaluated, preferably better compared. Generally, the smaller the calculated normalized driving comfort value, the better the driving comfort.

[0055] With the aid of the normalized comfort value KPI proposed in this way, the existing comfort-related measured variables can be converted into a new objectively comparable measure for driving comfort. This new driving comfort measure represents a normalized cost function. With the aid of such a comfort value, different driving styles can be objectively compared with one another and / or evaluated across manufacturers even during the development process. This allows for better coordination.

[0056] exist Figure 3 , a possible driving route for a motor vehicle 10 is shown by way of example. The driving route is defined by a starting point S and a destination D. Figure 3 The length of the section shown in is 11 km. Figure 3 A number of stations 1 to 5 along the route are shown. The first time value Z1 is estimated to be 22 minutes. Figure 3 In the example of , the cost function can also be normalized with respect to the length of the section. The normalization with respect to the length of the section can be expressed with the aid of a corresponding correction factor. The correction factor CFR is in particular the quotient of the time value and the length of the section. Figure 2 In the case of , the correction factor CFR=22×60:11=120 seconds per kilometer. The correction factor therefore has in particular the unit seconds per meter (s / m). Depending on the application, a conversion with respect to the units must also be performed. The correction factor CFR corresponds to the kilometer time, which is also referred to as the pace. The kilometer time is in particular the reciprocal of the speed.

[0057] exist Figure 4 , the results of several comfort value KPIs are shown next to each other. Figure 4 and Figure 5 The two diagrams shown are titled "Comfort KPI". The left diagram shows five different drives, all of which were carried out with the same control unit A or with the same driving style. Figure 4The journeys shown in FIG. 1 involve different routes with different traffic densities. The different journeys and sections are indicated by numbers. A1 indicates the first section, A2 indicates the second section, and so on. All sections are in Figure 4 The control unit A is implemented in the process. The control unit A can be a person or an onboard computer to realize autonomous control of the motor vehicle 10. In autonomous driving, different driving modes or driving styles are caused by the corresponding control unit or person. Six bars are drawn in each driving, in which the comfort value KPI and the elapsed time t represent the largest share. The rest is distributed on the longitudinal acceleration ax, the lateral acceleration ay, the longitudinal jerk jx and the lateral jerk jy. Figure 4 The left area of ​​shows the comfort value KPI without normalization. Figure 4 Compared to the right graph, the associated KPI values ​​experience stronger fluctuations.

[0058] Figure 4 The figure on the right shows the Figure 4 The same situation in the left figure of , where a corresponding normalization has been performed. Here it can be clearly seen that the dispersion at the comfort value KPI is significantly reduced. Figure 4 In the right diagram in , normalization reduces the dispersion of the comfort values ​​KPI, where the ideal result is a dispersion of 0%. In the left diagram, the maximum deviation is 42%, while in the right diagram the comfort values ​​KPI deviate much less from one another. Disturbing influences that extend the duration of a route or a trip but have no direct effect on driving style or driving comfort can thus be calculated better. Driving comfort or driving styles can thus be better compared with one another. In many cases, maximum driving comfort is desired. This generally corresponds to the lowest comfort value. In this setting, the weighting factors are predetermined and are not changed. Figure 4 In the example shown, the fifth road section A5 can achieve the greatest driving comfort.

[0059] The third road segment A3 represented by the third group of bars (third group from the left) is Figure 4 In the example of , the third run A3 has the worst comfort value KPI. However, with the help of a customer-specific individual adjustment to the desired driving style, the third run A3 can appear as the best run. This would be the case if a sporty driving style is desired. This can be represented by a corresponding adjustment of the weighting factors. In this case, however, the third run A3 is compared with the fifth run A5 (on the right side of the diagram). Preferably, only those control units that are assigned to the same driving style or driving mode can be compared with one another. Figure 4 In the examples, the same control unit A is used in each case. The designations A1 to A5 are intended to illustrate that Figure 4In the example of FIG. 1 , the same control unit A is always used. Different distances can be compared here. Thus, for example, a comfortable and / or more efficient route for operating the motor vehicle can be selected or preset.

[0060] Figure 5 Likewise, two diagrams are shown, which show the comfort value KP1 and the associated influencing variables t, ax, ay, jx and jy. Figure 4 As in the example above, the comfort value KP1 is decisively influenced by the elapsed time t. For a more detailed analysis, Figure 5 The right figure shows an enlarged view in the range of 0 to 0.2 on the Y axis. Figure 5 In the example shown in FIG. 1 , different control units F to I are compared with one another. Figure 5 The right-hand figure of shows clearly that control unit I has a greater longitudinal acceleration ax than control unit H. This may be due to the fact that control unit I is not correctly classified, i.e. it represents a sporty driving style rather than an efficient driving style, or control unit I is actually less suitable for efficient and comfortable driving than control unit H. By normalizing the cost function CF, an adjusted comfort value KPI can be generated, which can calculate the extended driving time. The normalization of the cost function CF has the effect that influencing variables or parameters typical of the driving style are expressed more strongly.

[0061] The method may include measuring driving parameters of the motor vehicle 10 on a determined route, wherein the driving parameters may include longitudinal acceleration ax, lateral acceleration ay, longitudinal jerk jx, lateral jerk jy, driving speed or driving time. Optionally, GPS coordinates may be incorporated into the determination of the cost function CF. Using the above parameters, the value of the cost function CF may be calculated at a determined average speed and / or travel time. Thus, a comfort value KPI may be derived with the aid of the cost function. The driving parameters preferably include real-time navigation data in order to take into account the influence of traffic and route-specific features, such as roundabouts, intersections, traffic lights, etc.

[0062] With the aid of the proposed new comfort value (including normalization of the cost function), different driving styles can be better identified based on the new comfort value KPI. The cost function CF can achieve a balance between the comfort value KPI and the horizontal acceleration. The normalization of the cost function CF or the comfort value KPI with respect to the route length can achieve comparability of different routes. With the aid of the correction factor CFR, parameters of the different routes that are not directly related to the driving style can be better calculated.

[0063] The correction factor CFR can be determined by the following formula.

[0064] CFR = (z1 or z2) / length

[0065] Formula 3

[0066] In Formula 3, the length of the route is referred to as “length.” Z1 and Z2 represent the first time value Z1 or the second time value Z2.

[0067] Additionally or alternatively, the normalization may be extended to the value of the cost function j. This may be expressed as follows.

[0068] j=J / length

[0069] Formula 4

[0070] The normalized cost function CF is denoted here by j. Preferably, equations 1 and 2 are used for the method and the normalization.

[0071] The normalized cost function J according to formula 4 can be used as a result for comparison, in particular as a comparison value for the comfort value per kilometer. The normalized cost function J in particular represents a route-specific cost function value per kilometer. Therefore, the normalization can additionally include the normalization of the cost function CF or J.

[0072] The first time value Z1 or the second time value Z2 normalized to the length of the section according to formula 3 can illustrate the time-specific length characteristics for the section. According to formula 3, how much time is required for each kilometer of operation or how much time consumption is required for each kilometer. Therefore, the correction factor CFR defined according to formula 3 can allow the time consumption per kilometer to be evaluated. Therefore, normalization can also additionally include the normalization of the time value with respect to the length of the section. This normalization is particularly represented by formula 3. The values ​​calculated according to formulas 3 and 4 especially not only contain the section characteristics (in the form of the correction factor CFR) but also contain the measurement with the aid of the time sensor 11, the acceleration sensor 12 and / or the jerk sensor 13. Preferably, in addition to the comfort value KPI, the normalized cost function J and the correction factor CFR are also additionally determined during normalization and output or displayed when necessary. All determined variables, such as the comfort value KPI, the time value Z1, Z2, the normalized cost function J, the correction factor CFR can be displayed on a display or output from the audio output. All these values ​​can be displayed as an overall result.

[0073] With the aid of the second time value Z2, the comfort value KPI can take into account real-time information. In order to be able to robustly evaluate different driving styles and / or control units for autonomous or partially autonomous driving, the predetermined route section should be traveled several times with different driving styles or control units. Figure 5In the example, control unit H appears as a possible candidate for a control unit that enables comfortable and efficient driving. However, the data basis for determining or calculating the comfort value KPI should include multiple routes. Ideally, multiple comfort values ​​are averaged in order to better filter out fluctuations.

[0074] Reference numerals list

[0075] 10 Motor Vehicles

[0076] 11 Clock, time sensor

[0077] 12 (First) Acceleration sensor

[0078] 13 Jerk sensor, inertial sensor, second acceleration sensor

[0079] 14 Interface

[0080] 15 External navigation unit

[0081] 16 Internal navigation unit

[0082] x, y, z longitudinal axis, transverse axis, vertical axis

[0083] KPI Comfort Value

[0084] time, t time, elapsed time

[0085] ax longitudinal acceleration

[0086] ay lateral acceleration

[0087] jx longitudinal jerk

[0088] jy lateral jerk

[0089] Z1 first time value

[0090] Z2 Second time value

[0091] CF Cost Function

[0092] CFR Correction Factor

[0093] j is the value of the normalized cost function

[0094] J The value of the cost function

[0095] w ax ,w ay ,w jx ,w jy Weighting Factor

[0096] S Starting point

[0097] D. Destination

[0098] A, F, G, H, I respective control units, controllers

[0099] A1 to A5 Sections 1 to 5

Claims

1. A method for determining a comfort value (KPI) for a motor vehicle (10) in operation, comprising the following method steps: a) based on the time (t) that has elapsed during the operation of the motor vehicle (10), the measured longitudinal acceleration (ax), the measured transverse acceleration (ay) and a predefined weighting factor (w) for the longitudinal acceleration and the transverse acceleration ax 、w ay ) calculates a cost function (CF) for said comfort value (KPI), b) taking into account the current traffic volume provided by the navigation unit (15, 16), calling up a first time value (Z1) relating to an estimated travel time of the motor vehicle (10) and a second time value (Z2) relating to an expected actual travel time of the motor vehicle (10), c) normalizing the calculated cost function (CF) with the aid of the first and / or second time value (Z1, Z2) of the navigation unit (15, 16) in order to determine a comfort value (KPI) for the motor vehicle (10) in operation.

2. The method according to claim 1, wherein: In order to determine the comfort value (KPI), the cost function (CF) is associated with the first and / or second time value (Z1, Z2).

3. The method according to claim 2, wherein: To determine the comfort value (KPI), a cost function (CF) is divided by the first and / or second time value (Z1, Z2).

4. The method according to claim 1, wherein: In addition, the longitudinal jerk (jx), the transverse jerk (jy) and the weighting factor (w jx , w jy ) to calculate the cost function (CF).

5. The method according to claim 1, wherein: The calculation of the cost function (CF), the calling up of the first and / or second time value (Z1, Z2) and / or the normalization take place during operation of the motor vehicle (10).

6. The method according to claim 1, wherein: A plurality of comfort values ​​(KPI) are determined by multiple calculations, multiple calls of the first and / or second time values ​​(Z1, Z2) and / or multiple normalizations, the plurality of comfort values ​​(KPI) are compared with one another to evaluate the driving style, and autonomous or partially autonomous control of the motor vehicle (10) is provided based on the comparison.

7. The method according to claim 6, wherein: The comfort values ​​(KPI) are classified according to a plurality of predefined driving modes, and only the comfort values ​​(KPI) of the same driving mode are compared with one another.

8. The method according to claim 7, wherein: The weighting factor (w ax ,w ay ,w jx ,w jy ) is defined according to the corresponding driving mode.

9. The method according to any one of claims 6 to 8, wherein: A minimum comfort value (KPI) is selected from the plurality of comfort values ​​(KPI) for autonomously or partially autonomously controlling the motor vehicle (10) and / or a control unit (A, F, G, H, I) is provided for autonomously or partially autonomously controlling the motor vehicle (10).

10. The method according to claim 1, wherein: The cost function (CF) is additionally calculated as a function of the driving speed of the motor vehicle (10), GPS coordinates and / or the length of the route travelled.

11. A motor vehicle (10) comprising: - an acceleration sensor (12) for measuring the longitudinal acceleration (ax) and the lateral acceleration (ay), - a jerk sensor (13) for measuring the longitudinal jerk (jx) and the lateral jerk (jy), a clock (11) and a control unit (A, F, G, H, I), the clock (11) being used to measure the time (t) that has passed while the motor vehicle (10) is in motion, Based on the longitudinal acceleration (ax), the transverse acceleration (ay) and a predefined weighting factor (w ax 、w ay ) to calculate a cost function (CF) for a comfort value (KPI) based on the time (t) elapsed during the operation of the motor vehicle (10), - calling up from the navigation unit (15, 16) a first time value (Z1) relating to an estimated travel time of the motor vehicle (10) and a second time value (Z2) relating to an expected actual travel time of the motor vehicle (10), taking into account the current traffic volume, and - normalizing a calculated cost function (CF) with the aid of the first and / or second time value (Z1, Z2) of the navigation unit (15, 16) in order to determine a comfort value (KPI) for the motor vehicle (10) in operation.

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