Method for the adaptive determination of a maximum load of a particularly autonomously driving vehicle, computer program product, device and vehicle

Abstract

The invention relates to a method for the adaptive determination of a maximum load (17) of a vehicle (1), in particular an autonomously driving vehicle, comprising the following steps: determining the permissible maximum speed (13) in the current operating range (15) of the vehicle (1), in particular via map and route data of a control unit (14) of the vehicle (1); determining the maximum permissible load on components of the chassis of the vehicle (1); determining the maximum permissible load (17) of the vehicle (1) on the basis of the permissible maximum speed (13) and permissible wheel loads (8); transmitting the maximum permissible load (17) of the vehicle (1) to a vehicle control system (16).

Description

[0001] The present invention relates to a method for the adaptive determination of a maximum load of a vehicle, in particular an autonomously driving vehicle. The invention further relates to a computer program product, a device, and a vehicle.

[0002] Electric motors are increasingly being used to power motor vehicles, creating alternatives to combustion engines that require fossil fuels. Considerable efforts have already been made to improve the everyday suitability of electric drives and also to provide users with the same level of driving comfort they are accustomed to.

[0003] In addition to the increasing electrification of motor vehicle drivetrains, motor vehicles are also becoming increasingly autonomous. Particularly with the advent of automated electric vehicles and new complete vehicle concepts, so-called people movers, designed as autonomously driving vehicles, are increasingly being used in urban areas. An autonomous motor vehicle or self-driving motor vehicle is a motor vehicle that can drive, steer, and, for example, park without the influence of a human driver (highly automated driving or autonomous driving). A special form of autonomous motor vehicle is the autonomous passenger transport vehicle, which is also referred to as a people mover or autonomous people mover. In this context, autonomous means that none of the transported persons steer the vehicle; rather, the passenger transport vehicle is self-controlled or automatically controlled.

[0004] During design, the chassis of such people movers – and thus the components used (chassis, steering system, axle carrier, braking system, drive, etc.) – are configured according to the specifications or worst-case assumptions. The aim of this is to ensure that such a vehicle can still be operated in operation or in a worst-case scenario without having to oversize the necessary components (brakes, steering, drive).

[0005] Especially with people movers of this type, the vehicle's payload is usually subject to strong fluctuations, sometimes up to one ton, in order to utilize the maximum vehicle class. In practice, however, the maximum vehicle mass is usually not utilized; nevertheless, all components and systems must be designed for the maximum load. All mechanical components must be designed for the most critical load case in each case, such as chassis components such as springs and dampers for negotiating potholes or wishbones and the steering system for braking the vehicle in curves. However, the vehicle is usually not fully loaded and often moves in zones with reduced top speed, meaning that the chassis components, for example, are oversized in these situations.

[0006] It is therefore the object of the invention to avoid or at least reduce the problems known from the prior art and to provide a method by which oversizing, in particular of chassis components in a vehicle, can be reduced. Furthermore, the object of the invention is to realize an optimized computer program product, an optimized device for implementing the method, and an improved vehicle.

[0007] This object is achieved by a method for the adaptive determination of a maximum load of a vehicle, in particular an autonomous vehicle, comprising the following steps: - Determination of the maximum permissible speed in the current operating range of the vehicle, in particular using map and route data from a control unit of the vehicle; - Determination of the maximum permissible load on components of the vehicle's chassis; - Determination of the maximum permissible load of the vehicle on the basis of the maximum permissible speed and permissible wheel loads; - Transmission of the maximum permissible load of the vehicle to a vehicle control system;

[0008] The process thus makes it possible to determine a maximum payload and transmit it to the vehicle control system, ensuring the vehicle is always optimally utilized without compromising its structure or safety. This optimizes payload capacity and can help minimize the number of trips and increase logistics efficiency.

[0009] Determining the maximum permissible load on vehicle chassis components can be implemented, for example, through a combination of hardware and software elements that analyze and evaluate the structural stress limits of the chassis components, particularly in real time. The technical implementation could, for example, be realized through a sensor system for load measurement. Various sensors can be integrated into the vehicle's chassis to directly measure the loads to which the components are exposed. These include strain gauges, force sensors, pressure sensors in hydraulic systems or air suspensions, and acceleration sensors, which, in conjunction with the mass inertia properties of the components, can determine the forces acting on them.The data collected by the sensors can preferably be transmitted to a central control unit, where it is processed and evaluated using specific software. The control unit could be a specialized electronic control unit (ECU) designed for collecting and analyzing chassis data. The maximum permissible load values for the individual chassis-specific components can then be stored in a database within this control unit. This data includes, for example, information on material strength, manufacturer tolerances, safety factors, and the maximum permissible loads for each chassis component determined from test series or simulations.

[0010] The software in the control unit advantageously features specially developed algorithms to determine the current loads on the components from the sensor data. Influencing factors such as driving speed, vehicle mass, load status, road conditions, and driving dynamics (such as acceleration, braking, and cornering) are also taken into account.

[0011] After determining the current loads, a comparison is made with the stored permissible load values. If limits are exceeded, the system can send warning messages to the vehicle guidance system or make automatic adjustments, such as limiting the maximum speed or restricting the load weight.

[0012] The control unit is preferably networked with other vehicle systems via interfaces (CAN bus, LIN bus, or FlexRay). This allows the determined limit values and chassis status data to be used for further control decisions, such as vehicle dynamics control or for adapting driver assistance systems.

[0013] The feature "Determination of the maximum permissible speed in the current vehicle operating area" describes the process by which the maximum speed valid for a vehicle in a defined area is determined, taking into account local traffic regulations and the specific characteristics of the route the vehicle is traveling on. A vehicle's operating area refers to the geographical sector and driving environment in which the vehicle is currently traveling. This can include urban areas, rural roads, motorways, or special zones such as construction sites or school zones. The operating area is variable and is determined dynamically by the vehicle during its journey.

[0014] To determine the current location and operating area of the vehicle, a Global Positioning System (GPS) module is preferably installed in the vehicle. This module continuously provides precise location data and, together with vehicle sensors, can determine the vehicle's direction of movement and speed. The vehicle's control unit advantageously has an integrated map and route database, which contains, for example, information on speed limits, road types, traffic signs, and special regulations in certain zones. This data is continuously updated, either via an online connection or manual updates, to ensure accuracy. Alternatively or additionally, it is also conceivable that speed limits are recognized via optical detection of traffic signs. The control unit's software analyzes the information from the GPS module in real time and links it with the stored map and route data.This allows the software to determine the vehicle's position on the digital map and calculate the maximum speed permitted at that location.

[0015] Ideally, the software should be able to adjust the maximum speed limit based on the specific characteristics of the route. For example, reduced speed limits in construction zones or on sharp curves can be taken into account. Temporary changes in the traffic situation, perhaps communicated by traffic control systems, are also incorporated into the calculation.

[0016] Once the maximum permissible speed has been determined, this value is transmitted as a speed limit to other vehicle systems, such as the vehicle control system, the infotainment system, or driver assistance systems. This can be used to control vehicle speed or as a warning and notification for the driver.

[0017] This ensures that the vehicle is always operated in accordance with local traffic regulations, improving road safety and ensuring legal compliance. At the same time, this feature helps autonomous driving systems react appropriately to the situation and assist the driver in adhering to the speed limit.

[0018] According to an advantageous embodiment of the invention, an adjustment of the maximum permissible load can be made when the vehicle is in a zone with a reduced permissible maximum speed. This advantageous feature relates to the vehicle's ability to dynamically adjust its load capacity depending on the maximum permitted driving speed in the current zone in which it is traveling.

[0019] For example, an implementation can initially involve a geolocation system, usually a GPS module, which can determine the vehicle's exact location in real time. This system works hand in hand with a database or map service that contains the maximum permitted speeds in various zones. Furthermore, sensors integrated into the vehicle, such as pressure sensors or load cells on the suspension or in the cargo area floor, can continuously record the weight of the current load. This data is processed by a control unit to determine the current total load of the vehicle. Preferably, a central control unit, often an on-board computer or an ECU (Electronic Control Unit), is equipped with appropriate software to evaluate the incoming data.These software algorithms link information about the vehicle's current location with map data about the speed limits that apply there.

[0020] Advantageously, the software in the control unit includes logic that determines when the vehicle enters a zone with a reduced maximum permissible speed. This information can then be used to determine whether and how the maximum permissible load needs to be adjusted to account for the changed operating conditions. For example, it may be that a higher load is safe at lower speeds because lower dynamic forces (e.g., during cornering or braking) act on the chassis.

[0021] Based on the detected changes in the permissible load, the control unit can then automatically adjust operating parameters. This can be a payload limit that actively blocks the loading of additional passengers or cargo, or a warning to the driver or operator that the vehicle is overloaded and requires adjustment.

[0022] In order to inform passengers, the driver or the operating personnel about the adjustment of the maximum permissible load, the vehicle can preferably be equipped with a feedback system that can trigger optical or acoustic signals or display information on a screen.

[0023] The system should also preferably include the ability to update data on permissible loads and maximum speed in order to adapt to the latest standards and traffic regulations.

[0024] According to a further preferred development of the invention, the method may also additionally comprise the following steps: - Bringing the vehicle to a standstill; - Opening of at least one passenger door to allow persons to leave the vehicle and / or access the vehicle, - and / or - Opening of at least one luggage door to allow luggage to be removed from the vehicle and / or stored in the vehicle; - Closing the passenger door and / or the luggage door; - Determination of the wheel load acting on each vehicle wheel; - Comparison of the wheel loads with permissible wheel loads stored in a control unit, where ◯ In the event that the wheel loads are smaller than the permissible wheel loads, a first maximum speed is determined and transmitted to a vehicle control system as a speed limit, and ◯ In the event that the wheel loads are greater than the permissible wheel loads, a second maximum speed is determined which is lower than the first maximum speed and the second maximum speed is transmitted to a vehicle control system as a speed limit value; - Putting the vehicle into a driving state.

[0025] This can increase safety through an adaptive system by setting an appropriate maximum speed based on the vehicle's current payload. After stopping and exchanging passengers or luggage, an optimized speed is determined by comparing the actual wheel loads with the permissible values. This prevents overloading the vehicle, thus reducing material fatigue and extending the service life of the vehicle components. This conserves resources and also reduces operating costs.

[0026] Furthermore, according to a likewise advantageous embodiment of the invention, it can be provided that the inclination of the vehicle is determined; as well as a conversion of the inclination-dependent wheel loads of the vehicle to wheel loads standardized in a horizontal spatial plane; and a comparison of the standardized wheel loads with permissible wheel loads stored in a control unit, wherein in the event that the standardized wheel loads are smaller than the permissible wheel loads, a first maximum speed is determined and transmitted to the vehicle control system as a speed limit value, and in the event that the standardized wheel loads are greater than the permissible wheel loads, a second maximum speed is determined which is smaller than the first maximum speed and the second maximum speed is transmitted to the vehicle control system.Advantageously, the invention can also be further developed to take vehicle inclination into account. This ensures driving safety on different terrains, as dangerous situations that could arise due to changes in wheel load on inclines are anticipated. Standardization to a horizontal spatial plane enables precise and situation-specific adjustment of the maximum permissible speed, which improves driving safety and passenger comfort, especially in autonomous vehicles.

[0027] According to another particularly preferred embodiment of the invention, the wheel load acting on a vehicle wheel can be determined via the deflection of a suspension spring and / or the forces in the vehicle's air suspension and / or interior monitoring of the vehicle and / or an estimation of the weight based on camera recordings. The invention also offers the advantage that the diverse methods for determining wheel loads provide a high degree of flexibility and accuracy in determining the actual load. The use of sensors in the suspension spring and air suspension as well as interior monitoring and weight estimation using camera recordings enable a comprehensive database that supports conformity with applicable safety standards and simultaneously allows efficient utilization of the vehicle.

[0028] Furthermore, the invention can also be further developed such that the monitoring and control of the method is carried out at least partially by a control unit in the vehicle and / or at least partially by a connected cloud. Networked monitoring and control of the method, either directly in the vehicle or via a connected cloud, results in the advantage of large data processing capacity and remote monitoring options. System updates and optimizations can be carried out promptly and regardless of location, which increases operating efficiency and allows potential system errors to be corrected quickly. This increases the reliability and availability of the affected vehicles.

[0029] In a likewise preferred embodiment of the invention, it can also be provided that the first maximum speed is less than or equal to 100 km / h, preferably less than or equal to 80 km / h. Setting an upper limit for the first maximum speed advantageously ensures compliance with legal requirements and traffic safety guidelines. This facilitates both the homologation of the vehicle and its acceptance in road traffic, and promotes efficient operation, particularly in autonomous vehicles that must adapt to different traffic conditions.

[0030] The object of the invention can also be achieved by a computer program product stored on a machine-readable medium, or a computer data signal embodied by an electromagnetic wave, with a computer program code suitable for carrying out a method according to any one of claims 1-7. Using the computer program product and the computer data signal, existing vehicles can be cost-effectively equipped with the new function. This also enables subsequent implementation in older models and contributes to a longer service life and greater cost-effectiveness, since extensive hardware changes are not necessarily required.

[0031] The object of the invention can also be achieved by a device for implementing the method according to any one of the preceding claims 1-7. The device for implementing the method enables standardized integration into vehicles from different manufacturers. This facilitates the scalability of the technology and promotes its market penetration. The hardware solution can support future requirements and be updated through software updates.

[0032] Finally, the object of the invention can also be achieved by a vehicle comprising a device according to claim 9 and a device for determining the wheel load acting on a vehicle wheel. By integrating such a device directly in the vehicle, the vehicle is enabled to determine the load on the wheels independently and without human intervention and to adjust the maximum speed accordingly.

[0033] According to an advantageous embodiment of the invention, it can be provided that the vehicle wheels of the first vehicle axle and the second vehicle axle of the vehicle are designed to be steerable, thereby further improving the maneuverability of the vehicle. In a likewise preferred embodiment of the invention, it can also be provided that the vehicle wheels of a vehicle axle can each be driven by an electric motor, thereby further improving the driving dynamics and driving stability of the vehicle.

[0034] It may also be advantageous to further develop the invention such that an actively steerable and drivable vehicle wheel, an electric machine, a steering actuator, and a braking device each form a wheel drive module. In this context, it is advantageous if the electric machine is designed as a radial flux machine. In this context, it is also particularly preferred for the vehicle to have at least four, preferably identical, wheel drive modules, which, on the one hand, further improves the modularity of the vehicle and, on the other hand, further optimizes the vehicle's driving characteristics.

[0035] A wheel drive module comprises, in particular, an electric wheel hub drive. Such electric wheel hub drives are well suited for use in commercial vehicles due to the space available and the driving dynamics requirements (comparatively low compared to a passenger car). In addition to the wheel hub drive, a wheel drive module can also include, for example, power electronics for supplying current to the wheel hub drive, a wheel bearing, a sensor for measuring torque, a sensor for measuring speed, a sensor for measuring weight, a sensor for measuring temperature, and / or a sensor for measuring noise.

[0036] A control unit, as used in the present invention, serves, in particular, for the electronic control and / or regulation of one or more technical systems of the motor vehicle. In particular, a control unit can be provided for controlling and / or regulating the load of the motor vehicle.

[0037] A control unit has, in particular, a wired or wireless signal input for receiving, in particular, electrical signals, such as sensor signals. Furthermore, a control unit preferably also has a wired or wireless signal output for transmitting, in particular, electrical signals, for example, to electrical actuators or electrical consumers of the motor vehicle.

[0038] Control and / or regulation operations can be performed within the control unit. It is particularly preferred that the control unit comprises hardware configured to execute software. The control unit preferably comprises at least one electronic processor for executing program sequences defined in software.

[0039] The control unit may further comprise one or more electronic memories in which the data contained in the signals transmitted to the control unit can be stored and read out again. Furthermore, the control unit may comprise one or more electronic memories in which data can be stored in a modifiable and / or non-modifiable manner.

[0040] A control unit can comprise a plurality of control devices, which are arranged, in particular, spatially separated from one another in the motor vehicle. Control devices are also referred to as electronic control units (ECUs) or electronic control modules (ECMs) and preferably have electronic microcontrollers for performing computing operations for processing data, particularly preferably using software. The control devices can preferably be networked with one another, enabling wired and / or wireless data exchange between control devices. In particular, it is also possible to network the control devices with one another via bus systems present in the motor vehicle, such as CAN buses or LIN buses.

[0041] The invention will be explained in more detail below with reference to figures without limiting the general inventive concept.

[0042] It shows: Fig. 1 an autonomously driving vehicle in a schematic representation, Fig. 2 a first method for the adaptive determination of a maximum load of the autonomously driving vehicle in a flow chart, Fig. 3 a force diagram of a wheel load on an inclined plane.

[0043] Based on the Fig. 1-2, a method for the adaptive determination of a maximum load 17 of a particularly autonomously driving vehicle 1 is described, as is also exemplarily shown in the Fig. 1 is outlined, explained in more detail.

[0044] First, in step a, the permissible maximum speed 13 in the current operating range 15 of the vehicle 1 is determined, in particular using map and route data from a control unit 14 of the vehicle 1. Subsequently, in step b, the maximum permissible load on components of the chassis of the vehicle 1 is determined. Based on the permissible maximum speed 13 and permissible wheel loads 8, the maximum permissible load 17 of the vehicle 1 is then determined in step c. This maximum permissible load 17 of the vehicle 1 is then transmitted to a vehicle control system 16.

[0045] An adjustment of the maximum permissible load 17 also takes place in particular when the vehicle 1 is in a zone with a reduced permissible maximum speed 13.

[0046] The procedure may additionally include the following steps: - Bringing vehicle 1 to a standstill; - Opening of at least one passenger door 2 to allow persons to leave the vehicle 1 and / or to enter the vehicle 1, - and / or - Opening of at least one luggage door 3 to enable removal of luggage from the vehicle 1 and / or storage of luggage in the vehicle 1; - Closing the passenger door 2 and / or the baggage door 3; - Determination of the wheel load 6 acting on each vehicle wheel 4; - Comparison of the wheel loads 6 with permissible wheel loads 8 stored in a control unit 5, whereby ◯ In the event that the wheel loads 6 are smaller than the permissible wheel loads 8, a first maximum speed 9 is determined and transmitted as a speed limit value 20 to a vehicle control system 11, and ◯ In the event that the wheel loads 6 are greater than the permissible wheel loads 8, a second maximum speed 10 is determined which is lower than the first maximum speed 9 and the second maximum speed 10 is transmitted as a speed limit value 20 to a vehicle control system 11; - Putting vehicle 1 into a driving state.

[0047] The inclination of the vehicle 1 can also be determined and the inclination-dependent wheel loads 6 of the vehicle 1 can be converted to wheel loads 7 standardized in a horizontal spatial plane. The standardized wheel loads 7 can then be compared with permissible wheel loads 8 stored in a control unit 5, wherein in the event that the standardized wheel loads 7 are smaller than the permissible wheel loads 8, a first maximum speed 9 is determined and transmitted to the vehicle control unit 11 as a speed limit value, and in the event that the standardized wheel loads 7 are greater than the permissible wheel loads 8, a second maximum speed 10 is determined which is smaller than the first maximum speed 9 and the second maximum speed 10 is transmitted to the vehicle control unit 11.

[0048] In the embodiments shown, the wheel load 6 acting on a vehicle wheel 4 can be determined via the deflection of a chassis spring and / or the forces in an air suspension of the vehicle 1 and / or an interior monitoring of the vehicle 1 and / or an estimation of the weight based on camera recordings. Furthermore, the monitoring and control of the method can be carried out at least partially by a control unit 5 in the vehicle and / or at least partially by a connected cloud 12, which is indicated by the arrows in the Fig. 1. As can be seen from the Fig. 1, the control unit 5, the vehicle control 11 and the vehicle control 16 can be integrated in a common control unit 18.

[0049] Fig.Figure 3 shows a force diagram of a wheel load on an inclined plane. Based on the force ratios shown, the inclination-dependent wheel loads 6 of the vehicle 1 can be converted to wheel loads 7 normalized in a horizontal spatial plane. On the inclined plane shown with an inclination angle of 20°, the weight force F acting on a wheel can be G of the vehicle into a normal vector F N1 and a restoring force F G parallel to the inclined plane. The driving force F acting on the vehicle wheel is analogously divided into a force component Fv parallel to the inclined plane and a normal vector component F N2 disassembled.

[0050] The invention is not limited to the embodiments illustrated in the figures. The above description is therefore not to be regarded as limiting, but as explanatory. The following claims are to be understood in such a way that a named feature is present in at least one embodiment of the invention. This does not exclude the presence of further features. Where the claims and the above description define 'first' and 'second' features, this designation serves to distinguish between two similar features without establishing a priority. List of reference symbols 1 vehicle 2 passenger doors 3 Luggage door 4 vehicle wheel 5 Control unit 6 Wheel load 7 wheel loads 8 wheel loads 9 Top speed 10 Top speed 11 Vehicle control 12 Cloud 13 Top speed 14 Control unit 15 Operating area 16 Vehicle control 17 Loading 18 Control unit 20 Speed limit

Claims

[1] Method for the adaptive determination of a maximum load (17) of a particularly autonomously driving vehicle (1), comprising the following steps: - Determination of the permissible maximum speed (13) in the current operating range (15) of the vehicle (1), in particular via map and route data of a control unit (14) of the vehicle (1); - Determination of the maximum permissible load on components of the vehicle's chassis (1); - Determination of the maximum permissible load (17) of the vehicle (1) on the basis of the maximum permissible speed (13) and permissible wheel loads (8); - transmission of the maximum permissible load (17) of the vehicle (1) to a vehicle control system (16); [2] Method according to claim 1, characterized by that the maximum permissible load (17) is adjusted when the vehicle (1) is in a zone with a reduced permissible maximum speed (13). [3] Method according to claim 1 or 2, characterized by that the procedure additionally includes the following steps: - bringing the vehicle (1) to a standstill; - Opening at least one passenger door (2) to allow persons to leave the vehicle (1) and / or to enter the vehicle (1), and / or opening at least one luggage door (3) to allow luggage to be removed from the vehicle (1) and / or luggage to be stored in the vehicle (1); - Closing the passenger door (2) and / or the luggage door (3); - Determination of the wheel load (6) acting on each vehicle wheel (4); - Comparison of the wheel loads (6) with permissible wheel loads (8) stored in a control unit (5), whereby ◯ In the event that the wheel loads (6) are smaller than the permissible wheel loads (8), a first maximum speed (9) is determined and transmitted as a speed limit value (20) to a vehicle control system (11), and ◯ In the event that the wheel loads (6) are greater than the permissible wheel loads (8), a second maximum speed (10) is determined which is lower than the first maximum speed (9) and the second maximum speed (10) is transmitted to a vehicle control (11) as a speed limit value (20); - Putting the vehicle (1) into a driving state. [4] Method according to claim 3, characterized by , that - the inclination of the vehicle (1) is determined; and - a conversion of the inclination-dependent wheel loads (6) of the vehicle (1) to wheel loads (7) standardised in a horizontal spatial plane; and - a comparison of the standardized wheel loads (7) with permissible wheel loads (8) stored in a control unit (5), whereby ◯ in the event that the standardised wheel loads (7) are smaller than the permissible wheel loads (8), a first maximum speed (9) is determined and transmitted to the vehicle control system (11) as a speed limit value, and ◯ in the event that the standardized wheel loads (7) are greater than the permissible wheel loads (8), a second maximum speed (10) is determined which is lower than the first maximum speed (9) and the second maximum speed (10) is transmitted to the vehicle control (11). [5] Method according to claim 3 or 4, characterized bythat the wheel load (6) acting on a vehicle wheel (4) is determined via the deflection of a chassis spring and / or the forces in an air suspension of the vehicle (1) and / or an interior monitoring of the vehicle (1) and / or an estimation of the weight based on camera recordings. [6] Method according to one of the preceding claims, characterized by that the monitoring and control of the method is carried out at least partially by a control unit (18) in the vehicle and / or at least partially by a connected cloud (12). [7] Method according to one of claims 3-6, characterized by that the first maximum speed is less than or equal to 100 km / h, preferably less than or equal to 80 km / h. [8] Computer program product stored on a machine-readable carrier, or computer data signal embodied by an electromagnetic wave, comprising a computer program code suitable for carrying out a method according to any one of claims 1-7. [9] Device (5,18) for carrying out a method according to one of the preceding claims 1-7. [10] Vehicle (1), comprising a device according to claim 9 and a device for determining the wheel load (6) acting on a vehicle wheel (4).

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