Method for driving an autonomous vehicle

Abstract

The present invention relates to a method for driving an autonomous vehicle within a defined speed range. The autonomous vehicle has at least one power device, and a characteristic curve family specific to the power device is provided for the at least one power device. The characteristic curve family specific to the power device is a characteristic curve family of the maximum torque related to speed. According to the own power level of the autonomous vehicle, a characteristic curve family specific to the power level is set for at least one power device of the autonomous vehicle. The characteristic curve family specific to the power level is a characteristic curve family of the own torque specific to the power level related to speed, and the own torque is less than the maximum torque. When driving the autonomous vehicle within the defined speed range, an additional torque is set for the autonomous vehicle as a supplement to the own torque specific to the power level.

Description

Field of the Invention

[0001] The present invention relates to a method for driving an autonomous vehicle / own vehicle (Eigen-Fahrzeug) within a defined speed range and a system for driving an autonomous vehicle within a defined speed range. Background Art

[0002] If a vehicle with a small internal combustion engine (VKM) is subjected to strong loads during driving, a higher transmission ratio or a hydrodynamic coupling with overshoot is used for the vehicle. However, the starting process obtained in this case is considered to be insufficiently sporty and not powerful enough, even with objectively good acceleration values due to the very significant continuity. Usually, the transmission ratio is matched when the vehicle starts with the internal combustion engine, where starting elements such as a torque converter are used, which are usually combined with a torque converter bypass clutch element. Here, when starting on a slope and / or with a trailer, the torque requirement increases, which makes it more necessary to adapt the transmission ratio of the transmission and use a torque converter that mechanically overshoots the torque.

[0003] US 2020 / 0171959 A1 describes an electric vehicle and a method for controlling the electric vehicle.

[0004] A torque assist device for a power device is known from WO 2013 / 054349 A2.

[0005] A strategy for downshifting the transmission ratio of a hybrid vehicle is known from US 2011 / 0172862 A1. Summary of the Invention

[0006] In this context, the object of the present invention is to appropriately perform the driving of a vehicle with high loads.

[0007] This object is achieved by a method and a system having the features of the independent claims. Embodiments of the method and the system result from the dependent claims and the description.

[0008] A method according to the invention is provided for driving an autonomous vehicle within a defined speed range. The autonomous vehicle, such as a motor vehicle, has at least one power device. Here, a characteristic curve family specific to the power device is provided for the power device, and this characteristic curve family specific to the power device is a characteristic curve family of the maximum torque related to speed. In addition, a power level is defined and / or set for the autonomous vehicle. Here, a characteristic curve family specific to the set power level is set for at least one power device of the autonomous vehicle according to the own power level of the autonomous vehicle, and this characteristic curve family specific to the power level is a characteristic curve family of the own torque specific to the power level related to speed, wherein the own torque set for at least one power device is less than the maximum torque set for it. In addition, when the autonomous vehicle is driving within the defined speed range of the autonomous vehicle or during driving, an additional torque is automatically set and / or automatically provided supplementarily to the own torque.

[0009] It is also feasible that the maximum torque, the own torque specific to the power level, and the additional torque are set and / or set in relation to the rotational speed in a manner equivalent to the speed related to the rotational speed of at least one power device.

[0010] In one design, it is proposed to execute this method when the autonomous vehicle starts, that is, when driving or operating starting from a speed of 0 km / h. An additional torque is provided and / or set when driving at a low speed. When the autonomous vehicle cannot accelerate further, an overshoot related to speed and / or rotational speed can also be provided, because in the design, for example, based on the overall mass to be moved and / or transported, the autonomous vehicle is under a strong load. In this method, the autonomous vehicle is additionally accelerated by the additional torque.

[0011] Possible defined speed ranges include smaller, two-digit speed values in kilometers per hour, such as ranges having values from 0 km / h to 10 km / h, from 0 km / h to 20 km / h, or optionally from 0 km / h to 30 km / h. In particular, it is possible that this range includes speed values from 10 km / h to 20 km / h. The speed value relates to the starting speed, where the autonomous vehicle starts from this starting speed and is additionally accelerated to a higher speed by the additional torque. If the minimum value of the defined speed range should be 0 km / h and the vehicle stops first, then the additional torque is correspondingly set when the autonomous vehicle starts. The additional torque can be particularly effective in the range from 10 km / h to 20 km / h and, for example, has a maximum value. It is also possible that when the additional torque has already been provided in the range from 0 km / h to 10 km / h, the establishment of the additional torque is delayed in time by a driving behavior filter or a driving behavior filtering device, but only has the maximum accelerating effect on the autonomous vehicle in the range from 10 km / h to 20 km / h.

[0012] When an autonomous vehicle is in motion or during its travel, for example, when starting, such as when starting on a slope and / or when starting with a trailer - due to an additional load that occurs based on the additional mass to be moved during travel, for example, when starting, when starting on a slope, and / or when towing a trailer - and an additional load is present or applied, an additional torque is automatically set and / or provided. Here, the additional load is automatically identified by at least one sensor. The speed range for setting the additional torque can start at a value of 0 km / h, where the autonomous vehicle can be rapidly accelerated or continuously accelerated, for example, when on a slope and / or when towing a trailer. Generally, the magnitude and availability of the additional torque enabled and / or provided as an overshoot torque can be adjusted taking into account other operating parameters related to the load of the autonomous vehicle. Such operating parameters are the loading of the autonomous vehicle and thus the mass that the autonomous vehicle has to drive or propel, for example, to accelerate, during travel. The loading and / or mass is determined, for example, using a spring travel sensor and / or a measurement sensor for mass, which are arranged in the chassis of the autonomous vehicle, and / or by estimating the mass, for example, based on the driving resistance during travel.

[0013] Furthermore, for at least one power device, the sum of the self - torque and the additional torque related to the power level is formed and set to be less than the maximum torque. It is feasible to set the additional torque in a power - level - specific manner as well. At least one power device is configured as an electric motor and is used and / or operated as an electric motor when traveling in a defined speed range, for example, when starting. This electric motor converts electrical energy from the energy source of the autonomous vehicle into mechanical energy for driving at least one drive wheel. Alternatively, an electric machine of this type can also be used and / or operated as a generator. Optionally, it can be considered that the autonomous vehicle also has at least one internal combustion engine as a power device for driving, where the autonomous vehicle is designed or referred to as a hybrid vehicle. The additional torque or the value of the additional torque is generally adjusted quantitatively in a defined speed range in relation to the speed value and / or in relation to the rotational speed value of at least one power device, that is, at least one electric motor and / or at least one internal combustion engine.

[0014] Typically, the additional torque is set by software-supported adaptation, supplementation, and / or data supply / data relationship of a power level-specific characteristic curve family that has at least one speed-dependent characteristic curve for the self-torque of the autonomous vehicle, such as a self-characteristic curve. It is possible here that within a preset or limited speed range of the autonomous vehicle and / or within a preset or limited rotational speed range of at least one power unit or the corresponding drive device, the corresponding value of the self-torque is generally increased quantitatively by the corresponding value of the additional torque. When the transmission ratio of the transmission of the autonomous vehicle remains unchanged, the rotational speed and the speed are largely proportional to each other and / or can be directly converted into each other.

[0015] The method is provided in a design for an autonomous vehicle having multiple, for example n, power units, where for the k-th power unit among the n power units, a power unit-specific k-th characteristic curve family with a k-th maximum torque related to speed is provided, here namely at least one k-th characteristic curve, and where for the autonomous vehicle, a power level-specific total self-torque characteristic curve family related to speed for all n power units is set according to its own power level, such as at least one power level-specific characteristic curve, and the power level-specific total self-torque of all n power units related to speed is less than the sum of all n maximum torques of the n power units, and where for the autonomous vehicle during driving, for example for starting and / or at the start, a common additional torque is automatically set and / or provided for all n power units within a limited speed range of the autonomous vehicle, and the common additional torque is distributed to all the power units. Here, one power unit can be assigned to each drive wheel of the autonomous vehicle respectively.

[0016] Furthermore, the method can be implemented for autonomous vehicles from the same vehicle product line. Here, each vehicle in the product line has at least one power device respectively, for example, having n power devices, where at least one power device or a corresponding one power device is configured to be structurally identical and / or unified for all vehicles in the product line. Here, for at least one structurally identical and / or unified power device arranged in each vehicle of the product line, the setting of the general and / or product line - covering maximum torque related to speed is for a characteristic curve family that is general for each vehicle and / or covers the product line, and this characteristic curve family includes at least one characteristic curve, and this characteristic curve family generally corresponds to the characteristic curve family specific to the power device described previously. In addition, different power levels of different magnitudes are set for the vehicles in the product line, where accordingly, each vehicle and thus each autonomous vehicle in the vehicle is set with its own power level. Here, for each vehicle, a power - level - specific characteristic curve family of its own torque related to speed is set according to its power level. If all vehicles in the product line have multiple or n power devices, then for each k - th power device in all vehicles, a maximum torque related to speed that covers the product line is set for the k - th power device. In addition, for the k - th power device in the autonomous vehicle at a specific power level, a power - level - specific characteristic curve family of its own torque related to speed is set. In the corresponding power - level - specific characteristic curve family of the autonomous vehicle, the torque related to speed and specific to the power level is less than the maximum torque and thus decreases relative to the maximum torque, and this also applies to the maximum possible value of the torque specific to the power level.

[0017] In another possible design of the method, a characteristic curve family specific to a power device with a maximum power related to speed is set for at least one power device of the autonomous vehicle. Additionally, for the autonomous vehicle, according to its own power level, a characteristic curve family specific to the own power related to speed and specific to the power level is set, where the own power set for at least one power device is less than the maximum power of the at least one power device. Moreover, for the autonomous vehicle, during driving, such as at startup and / or during startup, additional power is automatically set and / or provided within a defined speed range of the autonomous vehicle, where the sum of the own power and the additional power is less than the maximum power. When additional torque is set while driving within the defined speed range of the autonomous vehicle, additional power can be automatically generated. Alternatively or additionally, the additional power can also be directly set and / or provided. If the autonomous vehicle has n power devices, a characteristic curve family specific to the k-th power device with the k-th maximum power related to speed is set or will be set for the k-th power device. If the autonomous vehicle also belongs to the product series, at least one power device or the k-th power device for all vehicles in the product series is constructed to be structurally identical and / or unified. Here, for at least one structurally identical and / or unified power device of each vehicle in the product series, a characteristic curve family that is common and / or covers the product series and related to the maximum power related to speed is set to be common for each vehicle. When the power device is installed in the autonomous vehicle, according to the power level of the autonomous vehicle, a characteristic curve family specific to the own power related to speed and specific to the power level is set for each vehicle according to its power level, and the own power related to speed and specific to the power level is less than the maximum power related to speed that covers the product series, where the maximum own power is reduced relative to the maximum power, for example, restricted / suppressed.

[0018] Furthermore, driving behavior filtering is performed on the additional torque. The overshoot of the own torque in the form of the additional torque, which is set and / or adjusted in relation to the respective power levels of the autonomous vehicle, is selected in combination with the driving behavior filtering, such that when driving within a defined speed range, for example during startup, a harmonious buildup of the total torque of the autonomous vehicle is formed and only a small amount of power overshoot is formed. This creates the impression of a more dynamic and powerful driving behavior, where, for example, the complete data for accelerating the autonomous vehicle from 0 km / h to 100 km / h is only slightly changed. Generally, the acceleration from 0 km / h to 100 km / h only lasts for a few seconds, and the higher the power level of the autonomous vehicle, the shorter the duration of the acceleration. When increasing or overshooting the own torque by the additional torque, the duration of the acceleration is only shortened by a fraction of a second, for example, shortened by 0.1 s to 0.2 s. Additionally, a data supply to the driving behavior filtering device or the driving behavior filter that is coordinated with the total or all torques to be achieved is realized. With the driving behavior filtering, the filtered additional torque is determined from the unfiltered own torque preset in relation to the speed according to the characteristic curve family specific to the power level, and by means of this additional torque, a too rapid buildup of the total torque, which is the sum of the own torque and the additional torque, is avoided.

[0019] Driving behavior filtering is generally a temporal filtering of the torque desired by the driver of the autonomous vehicle and / or preset, for example, by operating an input module (usually the accelerator pedal). It is also feasible that during the cruise driving, autonomous driving, or self-driving of the vehicle, such desired and / or preset torques, such as the driver-expected torque, are automatically preset by a driving assistance device. Here, in order to provide the desired torque (a target value is usually preset for the desired torque), an additional torque is set within a defined speed range. The driving behavior filtering can be designed as a temporal filtering function or a temporal filter, a PT1-element / link, or a more complex filter. Generally, the driving behavior filtering can be implemented by a transfer element of automatic control / regulation technology, such as an LZI-transfer element, and then, if necessary, using a PT1 element. Additionally, a gradient limit for the additional torque to be set can be realized. This gradient limit is generally also related to the current value or magnitude of the torque (usually the total torque) of the autonomous vehicle and is set quantitatively and differently according to the torque and, in the design, also according to the speed and / or rotational speed. Here, the gradient for limiting the additional torque is, for example, very gentle or correspondingly small for small values of approximately 0 Nm or smaller values, such as a maximum of 5 Nm or 10 Nm.

[0020] This filtering of the additional torque, for example driving behavior filtering and / or gradient limitation, results in a delayed build-up of the total torque, where comfort is increased when, for example, the torque desired or preset by the driver and / or the driving assistance system changes rapidly. Here, the maximum additional torque or the corresponding maximum value is enabled delayed accordingly. The driving behavior filtering depends on different operating parameters of the autonomous vehicle, such as its mass and / or the mass of the overall propulsion, which is related to the loading of the autonomous vehicle and also related to a trailer that may be towed, and alternatively or additionally can also be adjusted or set by the driver by selecting the operating mode of the autonomous vehicle. Here, for example, the sport mode as an operating mode results in reduced driving behavior filtering, while conversely, for example, the comfort mode as an operating mode results in stronger driving behavior filtering. If the driving behavior filtering is configured as a time filter or a time filtering function and is adjusted, for example, by a PT1 element, it is feasible that the delay of the additional torque is not set and / or implemented in proportion to the speed of the autonomous vehicle. If the autonomous vehicle is additionally loaded, for example, due to a trailer and / or on a slope, it is feasible that the full additional torque or the maximum value for the additional torque is already provided at a very low speed, for example already from 0 km / h up to 5 km / h or 10 km / h, in order not to slow down the acceleration and to reach the desired speed quickly.

[0021] The system according to the invention is designed to drive an autonomous vehicle, for example start up, within a defined speed range of the autonomous vehicle, where the autonomous vehicle has at least one power unit. The system has a computing unit and a memory, where the memory is configured to store at least one family of characteristic curves, which usually includes at least one characteristic curve. Here, usually a family of characteristic curves of the speed-dependent maximum torque of at least one power unit is provided, which is stored or can be saved in the memory. The memory is designed to store, for at least one power unit of the autonomous vehicle, a power-rating-specific family of characteristic curves according to the own power rating of the autonomous vehicle, and to set, using the power-rating-specific family of characteristic curves, the speed-dependent, power-rating-specific own torque of the autonomous vehicle, which own torque is less than the maximum torque. The computing unit is designed to automatically set an additional torque for the autonomous vehicle and to cause, when starting up and / or during start up within the defined speed range of the autonomous vehicle, an additional torque to be provided by at least one power unit in addition to the own torque.

[0022] It is feasible that the additional torque is automatically set by the computing unit depending on the additional load of the autonomous vehicle when driving, for example when driving on a slope and / or due to a trailer to be towed, within the defined speed range, for example speed-dependently, i.e., according to the absolute value of the speed within the range provided for this purpose, where the additional load is generated based on the mass to be moved by the autonomous vehicle. It is feasible that an embodiment of the proposed method is carried out using an embodiment of the proposed system.

[0023] Using the method and system, for an electrically driven autonomous vehicle and / or in an electrically driven autonomous vehicle, an overshoot of its own driving torque as its own torque, such as a starting overshoot, can be implemented. The own driving torque is increased and / or overshot as an additional driving torque that is an additional torque within a speed range. Each of the described characteristic curve families, namely the characteristic curve family specific to the power level, the characteristic curve family specific to at least one power device, such as the characteristic curve family specific to the k-th power device, and / or the general and / or product line covering characteristic curve family, has at least one speed-dependent characteristic curve, such as a plurality of characteristic curves, for the corresponding torque and / or the corresponding power.

[0024] It is stipulated by using the method and system that, taking into account the additional torque, the speed-dependent, power-level-specific characteristic curve family is adjusted / fine-tuned, and thus at least one power device is adjusted for at least one callable and / or available torque in a low-speed range, such as from 0 km / h to 10 km / h and / or from 10 km / h to 20 km / h, and in an implementation from 0 km / h to 20 km / h. And the application or use of the driving behavior filter is adapted specifically based on the characteristic curve family. Here, the callable torque when driving within a defined speed range is obtained from the own torque together with the additional torque. Here, the callable and / or available torque is not increased by the additional torque as a whole over a wide range, but only within the selected speed range starting from the own torque. Here, a target value to be achieved is preset for the total torque, and the target value is obtained from the value of the own torque and the value of the additional torque. Here, for different vehicles of a product line with different power levels set for it, while maintaining the power differences set for marketing and pricing, the driving performance and traction of the autonomous vehicle can be improved in the low-speed range, where the autonomous vehicle belongs to this product line. Here, at the same time, aspects of drivability during the driving of the autonomous vehicle, such as starting, are considered, that is, the establishment of the torque controllable by the driver or the torque overshoot starting from the own torque specific to the power level.

[0025] To implement the driving of an autonomous vehicle, for example, to implement a starting process and thus to start an autonomous vehicle, the power-level-specific characteristic curve family of the own torque supplemented by the additional torque is used to preset the target value of the total torque that is to be achieved by at least one power device of the autonomous vehicle.

[0026] The total torque curve provided therefor has a relatively large value at low speeds - when the self-torque increases the additional torque - and this value drops to a constant value when the speed increases or the speed increases accordingly, because no additional torque is set for higher speeds. This constant value then exists in the power hyperbola when the preset power of the power or the corresponding target value of the power is reached, and the power hyperbola results from the self-power plus the additional power in the design.

[0027] The method is designed for autonomous vehicles from a product range including different vehicles. Here, all vehicles of the product range each have the same at least one power device. Since different power levels are set for the vehicles of the product range, for each power level of the autonomous vehicles in all vehicles, the maximum torque, i.e., the self-torque and / or the maximum power, i.e., the self-power, are set according to the characteristic curve specific to the power level and / or usually with software support, where the higher the power level assigned to the corresponding autonomous vehicle within the product range, the higher the maximum achievable torque and / or the maximum achievable power.

[0028] Here, using the additional torque in each power level of the autonomous vehicle, the overshoot data of the available self-torque are respectively incorporated into the characteristic curve family specific to the power level, and the characteristic curve family specific to the power level is supplemented with this through the overshoot set according to the additional torque. Since the maximum torque specific to the power level of at least one power device and / or the highest power specific to the power level are greater than the self-torque and / or the self-power plus the additional torque and / or the additional power, a drive overshoot based on a unified drive for all vehicles of the product range can be correspondingly achieved, or a drive overshoot of at least one power device of the autonomous vehicle can be correspondingly achieved, because a reserve for the additional torque and / or the additional power is provided therefor. It is possible here to adjust the drive or at least one power device provided for the autonomous vehicle through software-supported matching of the unified drive, for example, by limiting.

[0029] The method is implemented when the autonomous vehicle is traveling in a limited speed range, for example, during a starting process, such as when traveling with a trailer on a slope, or when distributing the total torque (torque distribution or μ distribution) obtained from the sum of the self-torque and the additional torque to multiple drive wheels of the autonomous vehicle. Here, in a possible design, the torque for the corresponding drive wheel is supported by the unilateral braking pressure acting on the drive wheel, whereby the torque actually generating a propulsive effect on the drive wheel is reduced. Even in this case, when the autonomous vehicle hardly accelerates or only very slowly accelerates, the overshoot of the corresponding self-torque provided by the additional torque can be used by the driver for a long time, and a reliable driving, such as a reliable starting process, is achieved.

[0030] Furthermore, it is possible to subjectively perform a significantly more dynamic driving in a limited speed range, such as a significantly more dynamic starting process. Objectively, the traction of the autonomous vehicle is significantly improved. This is also feasible in battery - powered autonomous vehicles (BEVs) with a low power rating or power class. In addition, the acceleration process of the autonomous vehicle from 0 km / h to 100 km / h is shortened and thus improved. In addition, for different vehicles of the same product series with drive devices of different power sizes or different power classes, a power - price - related distribution can be maintained. Here, no additional hardware or software costs are incurred because data is provided for the existing or original software only by adapting the power - class - specific characteristic curve family of the autonomous vehicle, and thus data related to the additional torque - based speed - related boost or overshoot is supplemented and / or adapted.

[0031] It can be achieved with the common electric drive device of the autonomous vehicle that, even when directly coupled to the drive wheels via a transmission and without a starting element, an additional torque set for overshoot can be output starting from a rotational speed of 0 revolutions per minute and / or a speed of 0 km / s of the autonomous vehicle at least within a preset speed range, wherein the maximum torque of the drive device is obtained from the self - torque and the additional torque.

[0032] Furthermore, a maximum self - torque initially set for the autonomous vehicle according to its power class is set through software and / or data supply. Here, data is initially supplied for the power - class - specific characteristic curve family of the self - torque of the autonomous vehicle according to its power class. Here, in the case of using the power - class - specific characteristic curve family, starting from a rotational speed of 0 revolutions per minute and / or a speed of 0 km / h of the autonomous vehicle, the self - torque set for the autonomous vehicle is output as the maximum driving torque, for example, constantly, which results in a stable driving, such as a stable starting process. Now, in this method, it is proposed to supplement the initially set maximum self - torque related to the corresponding power class with an additional torque set for overshoot. It is feasible here that the power class of the autonomous vehicle is increased at least during driving, such as during starting, in a low - speed range defined or set for this purpose, by the additional torque and, if necessary, also by additional power, wherein the limitation of the maximum torque and / or the maximum power of at least one power device to the initially set power class is lifted, and further, the limitation of the maximum torque and / or the maximum power of at least one power device to the self - torque specific to the power class and / or the self - power specific to the power class during driving, such as starting, is lifted.

[0033] This is set, for example, in special situations, such as when an autonomous vehicle with a trailer is driving on a slope, especially when starting. Although the autonomous vehicle initially has a small power rating and thus too little traction force. However, the traction force is increased by overshooting its own torque with an additional torque, because at least one power device is designed to also generate a higher traction force, which would otherwise be reduced and / or limited according to the power rating initially set for the autonomous vehicle.

[0034] In one design, at least one power device is used to directly drive the autonomous vehicle or its drive wheels, where the otherwise common gear ratio adaptation is eliminated. It is feasible here that the total torque and / or total power of the autonomous vehicle are overshot as a function of speed during driving, for example during starting. Here, the overshoot of a usually set hydrodynamic coupling is simulated and / or imitated. For this purpose, a characteristic curve family that is specific to the power rating and can include multiple characteristic curves is matched purely by software support, where all the characteristic curves are matched accordingly. Thus, the total torque is formed by the vehicle's own torque initially set in a power rating-dependent manner and an additional torque set for overshooting.

[0035] It is also proposed that the autonomous vehicle has multiple sensors for identifying the slope and / or the attached trailer, such as multiple inertial sensors, slope sensors, and mass sensors for multiple spatial directions. The computing unit or corresponding computing platform of the autonomous vehicle is, for example, configured as a high-performance computing platform (HCP). In addition, the autonomous vehicle has speed sensors for the drive wheels and at least one power device. In addition, the autonomous vehicle has an integrated speed regulator that has a damping device in at least one power device. To provide the additional torque, the speed of at least one power device and / or at least one drive wheel is considered. In this method, a cooperative regulation concept with an anti-lock function (ASR) and a differential lock (EDS) is also provided. In the method, sufficient drive reserves are provided for the total torque, for example designed as torque, and the power of at least one power device by means of a corresponding overshoot. The power rating-specific characteristic curve family of the vehicle's own torque and its own power is adapted in a power rating-specific manner using the drive software provided by the computing unit and / or the memory.

[0036] It goes without saying that the features described above and those to be described below can be used not only in the combinations separately described, but also in other combinations or individually, without departing from the scope of the invention. Description of the Drawings

[0037] The invention is schematically illustrated in the drawings by way of embodiments and is described schematically and in detail with reference to the drawings.

[0038] Figure 1A diagrammatic illustration shows a graph with operating parameters of an autonomous vehicle, which uses an embodiment of the system according to the invention in an embodiment of the method according to the invention. Detailed Embodiment

[0039] Figure 1 The graph 2 in it includes an abscissa 4 and an ordinate 6. In addition, a box 8 is shown here with a dashed border, in which a partial part of the graph 2 is enlarged and shown in detail on the right side of the graph 2.

[0040] The system according to the invention is provided for an autonomous vehicle, such as a motor vehicle, wherein the system also includes a computing unit and a memory of the autonomous vehicle for the implementation of an embodiment of the method according to the invention, i.e., for monitoring and thus for controlling and / or regulating.

[0041] It is proposed here that the autonomous vehicle originates from a product series having a plurality of different vehicles, such as motor vehicles. Here, each vehicle in these vehicles of the product series has a power plant, usually an electric motor, which is structurally the same for all vehicles of the product series and is thus constructed as a unified power plant.

[0042] In the graph 2, the speeds of the vehicle and the autonomous vehicle are plotted along the abscissa 4. Along the ordinate 6, the torques (such as driving torques) and their powers of the corresponding vehicle and the autonomous vehicle are plotted as operating parameters of the corresponding vehicle and the autonomous vehicle.

[0043] For a power plant that is uniformly or structurally the same for all vehicles of the product series, there is a characteristic curve 12 specific to the power plant and related to the maximum torque depending on speed, and / or covering the product series. When manufacturing the vehicles of the product series, such a power plant is installed in each of these vehicles. However, it is stipulated that different power levels are set and / or adjusted for different vehicles of the product series.

[0044] Here, for the first vehicle of the first power level (here the highest power level), the characteristic curve 14a specific to the first power level for setting the maximum first self-torque of the vehicle of this first power level is set through the characteristic curve 14a specific to the first power level. In addition, for the vehicle of the smaller second power level, the maximum self-torque is set and / or limited through the characteristic curve 14b specific to the second power level. In addition, for the vehicle of the third power level, the characteristic curve 14c specific to the third power level for setting and / or limiting the maximum self-torque of the vehicle of this third power level is set.

[0045] It is proposed here that for all speeds, the maximum torque is greater than the first additional torque of the vehicle for the first power level, which in turn is greater than the additional torque of the vehicle for the second power level, which in turn is greater than the additional torque of the vehicle for the third power level.

[0046] Figure 1 Chart 2 in [reference] also shows the additional torques 16a, 16b, 16c, i.e., the first additional torque 16a for the first self-torque, the second additional torque 16b for the second self-torque according to the second characteristic curve 14b, and the third additional torque 16c for the third self-torque according to the third characteristic curve 14c.

[0047] It is also proposed here that the vehicle of the second power level is also designed as or referred to as an autonomous vehicle, and an embodiment of the method according to the invention is described exemplarily here.

[0048] In a design, when the autonomous vehicle is driving on a slope or ramp, for example starting up and additionally having to tow a trailer as an additional load, an embodiment of the proposed method is implemented. It is considered here that the maximum torque according to the highest characteristic curve of the unrestricted power device is sufficient for the above situation. On the contrary, the self-torque of the vehicle of the second power level and thus of the autonomous vehicle according to the second self-characteristic curve 14b is too small. In this method, it is proposed that within a defined speed range, for example in the case of low speeds from 0 km / h to 10 km / h or 0 km / h to 20 km / h, during the driving of the autonomous vehicle, i.e., during driving, for example during starting, where the speed is at most 20 km / h, in addition to the self-torque, the second additional torque 16b is applied and / or provided.

[0049] In this context, reference is also made to a partial view of FIG. 2. This partial view shows that the self-torque set for the autonomous vehicle according to the second power level is increased by a second additional torque 16b, where a target value is provided for the total torque, which is obtained from the sum of the self-torque and the second additional torque 16b. The total torque, typically the real or actual torque, of the autonomous vehicle provided during driving, such as starting, is shown by the dashed line 18 in the partial view of FIG. 2. In addition, another curve 20 is also shown in this section, which represents the speed-dependent course of the power of the autonomous vehicle, where this total power of the autonomous vehicle is obtained from the self-power and the additional power related to the power level, however, the additional power is only provided when driving within a defined and / or set range of speeds, such as during starting. In this method, the following characteristic curve is used for the autonomous vehicle, which has a second self-characteristic curve 14b as the characteristic curve for the power level of the autonomous vehicle, and this characteristic curve is additionally supplemented and thus data-supplied by the second additional torque 16b, typically by the data for the second additional torque 16b, and the data includes the data of the self-characteristic curve.

[0050] Each of the characteristic curves 12, 14a, 14b, 14c shown in FIG. 2 for the maximum torque and the corresponding self-torque has a constant maximum value at low speed values, and this maximum value decreases at higher speed values taking into account the power hyperbola of the corresponding vehicle or autonomous vehicle taking into account the maximum value of the power hyperbola of the corresponding vehicle.

[0051] It is stipulated in this method that when driving within a defined range at low speed, such as during starting, the self-torque is overshot by the additional torque and thus adjusted.

[0052] The initially constant total self-torque for low speeds is overshot due to the additional torque in the low-speed range, where the total torque at higher speeds again corresponds to the self-torque, so that only the starting performance of the autonomous vehicle is affected, but not the acceleration ability.

[0053] Furthermore, in the design, the self-torque of the autonomous vehicle is increased very quickly, such as in a jump, by the additional torque through driving behavior filtering. Through this increase, a comfortable driving, such as starting, becomes possible. Although the actual total torque according to curve 18 decreases relative to the sum of the self-torque and the third additional torque 16c, the driving behavior of the autonomous vehicle can quickly and comfortably match the requirements for the target value of the total torque. Here, the total torque for the autonomous vehicle is constructed harmoniously. This can be achieved, for example, using a filtering function, such as using a PT1 filter or a PT1 element, a ramp limit, a gradient limit, and / or rounding (Verrundung), thereby matching the course of the total torque.

[0054] The acceleration of the autonomous vehicle is suppressed or limited by software. Although the overall acceleration process of the corresponding autonomous vehicle from 0 km / h to 100 km / h is maintained by the described power level distribution, the driving of the autonomous vehicle belonging to a relatively small power level, such as starting performance, is improved without increasing its acceleration, where the time for accelerating the autonomous vehicle is not affected or only slightly affected by the overshoot of the total torque.

[0055] List of reference numerals:

[0056] 2 Chart

[0057] 4 Abscissa

[0058] 6 Ordinate

[0059] 8 Box

[0060] 12 Maximum characteristic curve

[0061] 14a, 14b, 14c Additional characteristic curves

[0062] 16a, 16b, 16c Additional torques

[0063] 18, 20 Curves.

Claims

1. A method for driving an autonomous vehicle within a defined speed range, the autonomous vehicle having at least one power device, for which a power-device-specific characteristic curve family is provided, the power-device-specific characteristic curve family being a characteristic curve family of the maximum torque related to speed, setting a power-level-specific characteristic curve family for at least one power device of the autonomous vehicle according to the autonomous vehicle's own power level, the power-level-specific characteristic curve family being a characteristic curve family of the own torque specific to the power level and related to speed, the own torque being less than the maximum torque, when driving within the defined speed range of the autonomous vehicle, setting an additional torque for the autonomous vehicle as a supplement to the own torque specific to the power level, with the speed in the defined range being from 0 km / h to 30 km / h.

2. The method according to claim 1, wherein the method is executed when the autonomous vehicle starts.

3. The method according to claim 1 or 2, characterized in that, When the autonomous vehicle is additionally loaded, the additional torque is automatically provided.

4. The method according to claim 1 or 2, characterized in that The sum of the own torque and the additional torque is set to be less than the maximum torque.

5. The method according to claim 1 or 2, characterized in that, The additional torque is set by software-supported data processing of the power-level-specific characteristic curve family.

6. According to the method described in claim 1 or 2, for an autonomous vehicle having n power devices, a characteristic curve family specific to the k-th power device for the k-th maximum torque related to speed is set for the k-th power device among the n power devices. According to the own power level of the autonomous vehicle, a common characteristic curve family specific to the power level is set for the autonomous vehicle. The common characteristic curve family specific to the power level is the characteristic curve family of the total own torque specific to the power level and related to speed of all n power devices, and the total own torque is less than the sum of all n maximum torques of the n power devices, where When driving within the defined speed range of the autonomous vehicle, a common additional torque is set for all n power devices of the autonomous vehicle.

7. The method according to claim 1 or 2, for an autonomous vehicle from a vehicle product series, each vehicle of the product series respectively has at least one power device, the at least one power device is structurally the same for all vehicles of the product series, and the setting of the at least one structurally identical power device for each vehicle of the product series covers the characteristic curve family of the product series, and the characteristic curve family covering the product series is the characteristic curve family of the maximum torque related to speed covering the product series, wherein, For each vehicle of the product series, different power levels are set, and according to the power level of the autonomous vehicle, a power-level-specific characteristic curve family for setting the own torque specific to the power level and related to speed is set for the autonomous vehicle.

8. The method according to claim 1 or 2, characterized in that, A driving behavior filter is performed for the additional torque.

9. A system for driving an autonomous vehicle within a defined speed range, the autonomous vehicle having at least one power device, the system having a computing unit and a memory, a power-device-specific characteristic curve family is provided, the power-device-specific characteristic curve family being a characteristic curve family of the maximum torque related to speed of at least one power device, the memory being designed to store a power-level-specific characteristic curve family for at least one power device of the autonomous vehicle according to the autonomous vehicle's own power level, using the power-level-specific characteristic curve family to set the own torque specific to the power level and related to speed, the own torque being less than the maximum torque, the computing unit being designed to, when driving within the defined speed range of the autonomous vehicle, automatically set an additional torque for the autonomous vehicle as a supplement to the own torque specific to the power level, with the speed in the defined range being from 0 km / h to 30 km / h.

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