DE102020001797B4 - Method and device for axle load sensing - Google Patents

Abstract

Method for axle load sensing of an air-sprung vehicle axle (1) with at least one air spring (1a), comprising the steps: a) detecting an absolute air pressure pabs of the at least one air spring (1a); b) determining an atmospheric pressure patm based on a location of the vehicle axle (1) ; andc) determining an axle load acting on the vehicle axle (1) on the basis of the recorded absolute air pressure pabs and the determined atmospheric pressure patm.

Description

The invention relates to a method and a device for axle load sensing of an air-sprung vehicle axle with at least one air spring. Furthermore, the invention relates to a vehicle with a corresponding device for axle load sensing.

The reliable measurement of loads on the axles and/or other load-bearing components plays an important role, particularly in the commercial vehicle sector. Due to the usually high in this area and also - z. B. due to loading and unloading processes - experience has shown that the vehicle parts are often subject to changing forces, which can lead to wear and tear and thus to dangerous situations (e.g. broken axle). In addition, the distribution of the axle loads on the individual vehicle axles is a crucial parameter for checking the permissible total vehicle weight, which in turn can affect the vehicle handling (e.g. braking behavior, passability of bridges, etc.). Furthermore, knowledge of the current axle or wheel load distribution can also be used in a number of driving dynamics control systems, including e.g. B. ABS and / or ESP, protection systems against rollover of the vehicle and / or systems to stabilize body roll use.

There are various approaches in the prior art for determining axle or wheel loads, some of which are based on different measurement principles. In addition to the use of strain gauges and/or piezo-restrictive quartz force transducers, the axle load can also be sensed via pressure sensors connected to or arranged on the bellows of the air springs, particularly in vehicles with air suspension. In principle, both absolute pressure sensors and relative pressure sensors can be used for this purpose. With absolute pressure sensors, a pressure to be measured is absolute, i. H. recorded as a pressure difference compared to a preferably ideal (p=0 bar) vacuum. A pressure to be measured in the form of a pressure difference compared to a reference pressure (usually the atmospheric pressure at the place of use) is recorded with a relative pressure sensor. While in the case of relative pressure sensors, due to the required coupling to the atmospheric pressure, special requirements are placed on the mounting location, in the case of absolute pressure sensors, an adaptation or calibration to the actual external pressure, which is dependent on the weather and altitude, usually has to take place.

The latter can z. This can be done, for example, via an atmospheric pressure sensor that is additionally attached to the vehicle, which increases the assembly work and the susceptibility to errors.

In the DE 10 2017 008 973 A1 a method for determining the load of a vehicle is shown, the vehicle comprising an air suspension system with air suspension means which is installed on at least one front axle and at least one rear axle, the height of the bodywork in relation to the axles being able to be changed by controlling the amount of air in the suspension means and thereby changing the extension of the spring means. The method includes the step of determining the load on the suspension means based on the pressure in the suspension means and the aging of the suspension means.

the DE 100 29 332 A1 proposes providing information about the loading condition of a vehicle with at least one air-sprung axle by arranging a sensor for detecting the bellows pressure and a further sensor for detecting the compression travel on each of the air springs used in the wheel suspension of the vehicle and both the pressure and the spring signal can be further processed in an electronic computing device.

the DE 198 13 672 C1 shows an air suspension system for vehicles with air spring elements, a compressor and a central pressure accumulator fed by it for supplying compressed air to the air spring elements and an accumulator pressure sensor that detects the air pressure in the central pressure accumulator and generates a signal value that correlates therewith. The signal values of the accumulator pressure sensor are processed and pressurization of the central pressure accumulator by the compressor is initiated when a predetermined lower threshold signal value is reached and terminated when a predetermined upper threshold signal value is reached. An improvement in performance is achieved in that an ambient pressure sensor is provided, which detects the air pressure in the area surrounding the vehicle and the upper threshold signal value is varied as a function of this.

Accordingly, it is therefore the object of the invention to provide a solution for the reliable detection of loads on load-bearing vehicle parts, with which the disadvantages of the previous solutions can be avoided. In particular, it is an object of the invention to provide a solution by means of which a simple and reliable axle load sensing is made possible with few sensors.

These objects can be solved with the features of the independent claims. advantage tive embodiments and applications of the invention are the subject of the dependent claims and are explained in more detail in the following description with partial reference to the figures.

• Erfassen eines absoluten Luftdrucks pabs der zumindest einen Luftfeder. Anders ausgedrückt soll ein Luftdruck der Luftfeder (z. B. der Druck in einem Luftfederbalg der Luftfeder) absolut, d. h. als Druckunterschied gegenüber einem, vorzugsweise idealen, Vakuum, erfasst werden.

According to a first independent basic idea of the invention, a method is provided. The method is preferably a method for axle load sensing of an air-sprung vehicle axle with at least one air spring. According to the definition in B. Heissing (ed.) et al., Chassis Manual (DOI 10.1007/978-3-8348-8168-7), Chapter 4, the term "vehicle axle" should mean the entire connection between two wheels and wheel suspension for Individual wheels together with their connection to the chassis or the chassis frame are to be understood, in which case, for example, axles of non-motorized vehicles, such as trailers, semi-trailers, etc., should also be included. According to the above definition, e.g. B. a conventional car, regardless of the specific design, two axles and four wheel suspensions. The procedure comprises the following steps:

• detecting an absolute air pressure pabs of the at least one air spring. In other words, an air pressure of the air spring (eg the pressure in an air spring bellows of the air spring) is to be recorded in absolute terms, ie as a pressure difference compared to a preferably ideal vacuum.

Determining an atmospheric pressure patm based on a preferably current location of the vehicle axle. In other words, instead of actually measuring or detecting atmospheric pressure patm (e.g. via an additional atmospheric pressure sensor), atmospheric pressure patm, i. H. the hydrostatic pressure of the surrounding air, can be determined based on the location. As will be described in more detail below, patm can do this, e.g. B. via a stored atmospheric pressure map, which includes predetermined atmospheric pressure values for certain positions, and / or calculated using a predetermined functional relationship, such as the international altitude formula, for the respective location. Advantageously, this means that no further sensor is required to detect the atmospheric pressure patm.

berechnet werden. Dabei ist der erste Faktor die, in der in der Regel bekannte, gesamte aktuell wirksame Fläche A der Luftfeder, während der zweite Faktor die Differenz zwischen einem absoluten Druck p_atm und dem Atmosphärendruck p_atm enthält. Das Ergebnis letzterer Differenz beschreibt hierbei den in der Luftfeder herrschenden relativen Luftdruck p_rel.The method also includes the step of determining an axle load acting on the vehicle axle on the basis of the recorded absolute air pressure pabs and the determined atmospheric pressure patm. In other words, the axle load should ultimately be determined on the basis of the two variables pabs and patm, for which calculation methods known in the prior art can be used. For example, the axle load acting on the vehicle axle, ie the (weight) force exerted on the vehicle axle, via the relationship $$f_{acHse}=A\cdot \left(p_{abs}-p_{atm}\right)$$

be calculated. The first factor is the generally known, total currently effective area A of the air spring, while the second factor contains the difference between an absolute pressure p _atm and the atmospheric pressure p _atm . The result of the latter difference describes the relative air pressure p _rel prevailing in the air spring.

In this context, the step of determining the axle load according to a first aspect of the invention can also include converting the detected absolute air pressure p _abs into a relative air pressure p _rel based on the calculated atmospheric pressure p _atm . In other words, the quantity "relative air pressure p _rel " z. B. be calculated by the above-mentioned difference formation p _rel = p _abs - P _atm . Advantageously, the relative air pressure p _rel prevailing in the air spring can also be used for other applications, e.g. B. Pressure or level control of the air suspension system are available. The axle load can then - just as an example - be calculated using the following relationship: $$f_{acHse}=A\cdot p_{\mathrm{right}el}.$$

According to a further aspect of the invention, the method can include receiving position data and determining the location using the received position data. The position data is preferably GPS position data, which z. B. sent by multiple GPS satellites, or other satellite-based position data. In addition, or alternatively, the position data from terrestrial transmitters such. B. GSM, UMTS, LTE transmitters are received. Based on the received position data - i. H. of data that relate to a location (coordinates) of a location in space - a location is then to be determined, with methods known in the prior art (e.g. trilateration and/or triangulation) being able to be used. As a result, a location that is as up-to-date and precise as possible is advantageously available for determining the atmospheric pressure patm.

In addition or as an alternative, the method can also include direct reception of the preferably current location. In other words, the location should be determined externally and only the result should be made available. Advantageously, this can be done on a fahrzeugsei Term location determination can be dispensed with, which can save computing capacity there.

According to a further aspect of the invention, the step of determining the atmospheric pressure p _atm can include determining a location altitude h _s (e.g. an altitude above sea level or an ellipsoidal altitude). This can e.g. B. based on the location and / or the received position data. Furthermore, the step of determining the atmospheric pressure p _atm can then include a calculation of the atmospheric pressure p _atm based on a predetermined, ie previously specified, functional relationship between the atmospheric pressure patm and the location altitude h _s . For example, the atmospheric pressure patm can be calculated in the approximation of an isothermal atmosphere: $$p_{atm}=p_0\cdot e^{-\frac{H_s}{\mathrm{8,430}m}}$$

wobei hier die Standorthöhenlage h_s in Höhe in Meter über Normalnull einzusetzen ist. Vorgenannte funktionale Zusammenhänge sind dabei lediglich beispielhaft zu verstehen, sodass je nach konkretem Anwendungsfall auch weitere funktionale Zusammenhänge zwischen Atmosphärendruck p_atm und Standorthöhenlage h_s Verwendung finden können. Der Vorteil oben genannter Zusammenhänge ist dabei allerdings, dass allein auf Basis der Standorthöhenlage h_s eine einfache Atmosphärendruckbestimmung mit zumeist ausreichender Genauigkeit erfolgen kann.In this context, p ₀ should denote the air pressure related to sea level (e.g. 1,013.25 hPa) and h _s the site altitude above sea level. Alternatively, the international height formula can also be used as a functional relationship $$p_{atm}=1013.25\cdot {\left(1-\frac{0.0065\cdot H_s}{288.15}\right)}^{5.258}HPa,$$

where the site altitude h _s is to be used here in meters above sea level. The aforementioned functional relationships are only to be understood as examples, so that depending on the specific application, other functional relationships between atmospheric pressure p _atm and site altitude h _s can also be used. The advantage of the above relationships is, however, that a simple determination of the atmospheric pressure can usually be carried out with sufficient accuracy solely on the basis of the site altitude h _s .

In order to increase the accuracy when determining the atmospheric pressure p _atm , according to a further aspect of the invention, the method can also include detecting and/or receiving a location temperature T _s . A temperature of the environment or atmosphere at the location of the vehicle axle can be understood as the location temperature T _s . For example, the location temperature T _s can be detected using an outside temperature sensor and/or received from external transmitters. The transmission can take place, for example, via a cellular network, via "Car2Car" communication, via "Car2Infrastructure" communication or other "Car2x" communication. The atmospheric pressure p _atm can then be determined on the basis of the location temperature T _s . In other words, in addition to the location, preferably the location altitude, of the vehicle axle, the location temperature T _s should also be included when determining the atmospheric pressure p _atm , which advantageously also allows the meteorological condition of the atmosphere to be taken into account.

If the atmospheric pressure patm is determined, as mentioned above, via a predetermined functional relationship, the predetermined functional relationship—according to a further aspect of the invention—is a functional relationship between atmospheric pressure _patm , location altitude hs and location temperature _Ts .

According to a further aspect of the invention, the atmospheric pressure p _atm can be determined by means of an atmospheric pressure characteristic diagram. For this purpose, the atmospheric pressure map - the z. B. can be in the form of an atmospheric pressure database - include predetermined, ie predetermined, atmospheric pressure values for specific positions. As positions, z. B. defined by longitude and latitude, places on earth are understood. According to this aspect, instead of a corresponding calculation of the atmospheric pressure patm, the corresponding atmospheric pressure value can primarily be read out or queried from the atmospheric pressure characteristics map, which is preferably updated regularly. This can z. B. be stored in the vehicle and / or in an external storage device, wherein the method in the latter case can include a corresponding reception of an atmospheric pressure value.

Depending on the rasterization of the atmospheric pressure map, the location of the air spring will usually not directly correspond to a position entry in the atmospheric pressure map, so that the atmospheric pressure value of a position closest to the location can be used to determine the atmospheric pressure. In order to further increase the accuracy of the atmospheric pressure determination in an advantageous manner, the determination of the atmospheric pressure p _atm according to a further aspect of the invention can also include an interpolation between a plurality of predefined atmospheric pressure values. For example, the mean value of two or three atmospheric pressure values can be formed for this purpose, with the atmospheric pressure values being assigned to the two or three position entries in the atmospheric pressure characteristic map that are closest to the location. In addition or as an alternative, other methods of estimating the course of the atmospheric pressure between the predefined atmospheric pressures can also be used values are used, for example a polynomial interpolation.

According to a further aspect of the invention, if the method as mentioned above comprises detecting and/or receiving a location temperature T _s , the atmospheric pressure map can also be an atmospheric pressure-temperature map. In other words, the atmospheric pressure characteristics map should include predetermined, ie previously specified, atmospheric pressure values for specific positions and for specific temperatures. In this way, a simple possibility of determining the atmospheric pressure can advantageously be provided, in which the meteorological condition of the atmosphere is also taken into account.

According to a further aspect of the invention, the at least one air spring can be part of an air spring system for leveling the vehicle axle. In other words, the air spring system can be set up to regulate the distance between a vehicle body and the vehicle axle or the wheel suspension or wheels usually connected to it. Additionally or alternatively, the vehicle axle can be a rear axle and/or the air spring system can be a rear axle air spring system. Such a rear-axle air spring system is already present, for example, in semitrailer tractors and trucks of the BL (leaf-air) type. The BL type has a steel leaf spring on the front axle and on the. Rear axle installed an air suspension system. In this way, the method can advantageously use components that are already present.

In order to enable reliable axle load sensing even in the event of any changes in the level, the method can, according to a further aspect of the invention, include determining a level of the at least one air spring. In addition to direct detection of the height—referred to as level height—of the at least one air spring, a variable can alternatively also be determined from which the level height of the at least one air spring can be derived. For example, a distance between two parts (eg, vehicle body and vehicle axle) that are moving relative to one another—in the case of level changes—can be determined. Furthermore, the method can include determining the axle load acting on the vehicle axle, taking into account the level determined. i.e. The determined level height can be included in the determination or calculation of the axle load, for example in the form of a level-dependent, effective area A. The background here is that the effective area A of the air spring usually changes with the level height (e.g. due to a change the fold of the bellows) so that, despite the load remaining the same, there could be different axle load values at different heights. In order to compensate, the level determined should also be taken into account when determining the axle load. This can z. B. in the form of, for the respective type of air spring (rolling bellows, bellows, etc.) specified and / or previously calibrated, take place characteristics.

According to a further aspect of the invention, the air-sprung vehicle axle can comprise at least two air springs, preferably arranged at opposite ends of the vehicle axle, which are referred to below as the first and second air springs for better differentiation. In this case, the step of detecting can include both detecting a first absolute air pressure p _abs of the first air spring and detecting a second absolute air pressure p abs of the second air spring. Furthermore, the axle load can be determined on the basis of the detected first and second absolute air pressure pabs and the determined atmospheric pressure p _atm . For this purpose, for example, the mean value can first be calculated from the first and second absolute air pressure pabs. As an alternative to this, a corresponding axle load determination can also be carried out separately for each of the air springs (which generally corresponds to a wheel load determination) and then, if necessary, a weighted averaging of the axle or wheel loads can be carried out. As a result, asymmetrical load distributions can also be taken into account in an advantageous manner. In addition or as an alternative, the wheel loads determined in this context can also be made available to a driver and/or a driving dynamics control system.

According to a further aspect of the invention, the first and second air springs can be arranged at different points on the vehicle axle. The various points are preferably located at opposite ends of the vehicle axle and/or opposite longitudinal sides of the vehicle. For example, the first air spring--relative to the longitudinal direction of the vehicle--on a left-hand side and the second air spring--relative to the longitudinal direction of the vehicle--can be arranged on a right-hand side of the vehicle axle. As mentioned above, this is particularly advantageous in order to detect asymmetrical load distributions on the vehicle axle.

Furthermore, the invention also relates to a device for axle load sensing. In this case, the device should be set up to carry out a method as described in this document. For this purpose, the device can have at least one sensor device which is designed to measure an absolute air pressure p _abs of the at least one air spring to capture. Furthermore, the device can include a determination device that is designed to determine an atmospheric pressure p _atm based on a location of the vehicle axle. This can only be an example z. B. via a stored atmospheric pressure map and / or via a predetermined functional relationship, such as the international altitude formula, for the respective location. Furthermore, the determination device can be designed to determine an axle load acting on the vehicle axle on the basis of the detected absolute air pressure p _abs and the determined atmospheric pressure p _atm . Depending on . Embodiment, the device may have appropriate components, including z. B. a receiving device that is designed to receive position data and/or a location temperature, and/or a further sensor device that is designed to detect a location temperature, and/or a height measuring device that is designed to measure the level of the at least one air spring capture.

To avoid repetition, features disclosed purely in terms of the method should also apply and be claimable as disclosed in terms of the device and vice versa. The aforementioned aspects and features according to the invention, in particular relating to determining the atmospheric pressure and determining the axle load acting on the vehicle axle, therefore also apply to the device and the determination device.

Furthermore, the invention relates to a vehicle having a device for sensing the axle load, as described in this document. The vehicle is preferably a commercial vehicle. In other words, the vehicle can be a vehicle which, due to its design and equipment, is designed for transporting people, for transporting goods or for towing trailer vehicles.

For example, the vehicle can be a truck, a bus and/or a trailer truck.

• 1: ein Flussdiagramm des Verfahrens zur Achslastsensierung gemäß einer ersten Ausführungsform der Erfindung; und
• 2: eine schematische Darstellung eines Fahrzeugs mit einer Vorrichtung zur Achslastsensierung gemäß einer Ausführungsform der Erfindung.

The aspects and features of the invention described above can be combined with one another as desired. Further details and advantages of the invention are described below with reference to the accompanying drawings. Show it:

• 1 1: a flow chart of the method for axle load sensing according to a first embodiment of the invention; and
• 2 1: a schematic representation of a vehicle with a device for axle load sensing according to an embodiment of the invention.

Identical or functionally equivalent elements are denoted by the same reference symbols in all figures and some of them are not described separately.

1 shows a flow chart of the method for axle load sensing according to a first embodiment of the invention. The method is preferably a method for axle load sensing of an air-sprung vehicle axle 1 with at least one air spring 1a (eg a rolling bellows). The expression “air-sprung” can be understood here to mean a suspension system in which the compressibility of gases, in particular air, is used for the suspension of the vehicle axle 1 . In a step S1, the method includes detecting an absolute air pressure p _abs of the at least one air spring 1a. That is to say, in other words, an air pressure of the air spring 1a is to be detected as a pressure difference compared to a preferably ideal vacuum.

In a step S2, an atmospheric pressure patm is then determined based on a preferably current location of the vehicle axle 1. That is, instead of actually measuring the atmospheric pressure p _atm (e.g. via an additional atmospheric pressure sensor), the atmospheric pressure patm is to be measured in the present case , ie the hydrostatic pressure of the surrounding air, can be determined on the basis of the location. The example z. B. via a stored atmospheric pressure map, which should include predetermined atmospheric pressure values for certain positions, and / or calculated using a predetermined functional relationship, such as the international altitude formula, for the respective location.

berechnet werden, wobei der erste Faktor die, in der in der Regel bekannte, gesamte wirksame Fläche A der Luftfeder 1a angibt und der zweite Faktor die Differenz zwischen einem absoluten Druck patm und dem Atmosphärendruck patm enthält. Insgesamt wird dadurch auf vorteilhafte Weise ein Verfahren zur Achslastsensierung bereitgestellt, das mit wenigen Sensoren eine einfache und betriebssichere Achslastsensierung ermöglicht.In a step S3, an axle load acting on the vehicle axle 1 is then determined on the basis of the detected absolute air pressure pabs and the determined atmospheric pressure p _atm . In other words, the axle load should ultimately be determined on the basis of the two variables pabs and patm, for which calculation methods known in the prior art can be used. For example, the axle load acting on the vehicle axle 1 can be determined via the relationship $$f_{acHse}=A\cdot \left(p_{abs}-p_{atm}\right)$$

are calculated, the first factor indicating the generally known total effective area A of the air spring 1a and the second factor containing the difference between an absolute pressure patm and the atmospheric pressure patm. All in all a method for axle load sensing is thereby provided in an advantageous manner, which enables simple and reliable axle load sensing with few sensors.

2 shows a schematic representation of a vehicle 20 with a device 10 for axle load sensing according to an embodiment of the invention. The vehicle 20 is present - just as an example - to a semitrailer vehicle, ie a combination of a tractor 20a and a semitrailer 20b, the vehicle 20 in principle also different, z. B. can be designed as a truck with structure or as a bus. The tractor 20a comprises an air-sprung vehicle axle 1, which is the rear axle of the tractor 20a in this case and z. B. can be designed as an electronically controlled rear axle air suspension system for leveling the rear axle. The air-sprung vehicle axle 1a also has at least one air spring 1a, for example in the form of an air spring bellows, with at least two air springs 1a being arranged for suspension on the wheel sides of the vehicle axle 1 in the present example.

Furthermore, the vehicle 20 includes a device 10 for axle load sensing, which is set up to carry out a method as described in this document. For this purpose, the device 10 z. B. have at least one sensor device 2, which is designed to detect an absolute air pressure p _abs of the at least one air spring 1a. Furthermore, the device can include a determination device 3 which is designed to determine an atmospheric pressure p _atm based on a location of the vehicle axle 1 . This can only be an example z. B. via a stored atmospheric pressure map and / or via a predetermined functional relationship, such as the international altitude formula, for the respective location. To determine the location, the device 10 can also have a receiving device 4 which is designed to receive position data, preferably GPS position data, and to provide this to the determination device 3 for determining the location and thus the atmospheric pressure patm at the location. On the basis of the recorded absolute air pressure pabs and the determined atmospheric pressure p _atm , the axle load acting on the vehicle axle 1 can then be determined by means of the determination device 3 .

Although the invention has been described with reference to specific embodiments, it will be apparent to those skilled in the art that various changes may be made and equivalents substituted without departing from the scope of the invention. Accordingly, the invention should not be limited to the disclosed embodiments, but should include all embodiments falling within the scope of the appended claims. In particular, the invention also claims protection for the subject matter and the features of the subclaims independently of the claims referred to.

Reference List

1

vehicle axle

1a

air spring

2

sensor device

3

investigation facility

4

receiving device

10

Device for axle load sensing

20

vehicle

20a

tractor unit

20a

semitrailer

Claims (15)

Method for axle load sensing of an air-sprung vehicle axle (1) with at least one air spring (1a), comprising the steps: a) detecting an absolute air pressure pabs of the at least one air spring (1a); b) determining an atmospheric pressure patm based on a location of the vehicle axle (1); and c) determining an axle load acting on the vehicle axle (1) on the basis of the recorded absolute air pressure pabs and the determined atmospheric pressure patm. procedure after claim 1 , characterized in that the determination of the axle load includes a conversion of the detected absolute air pressure pabs into a relative air pressure p _rel based on the calculated atmospheric pressure patm. Method according to one of the preceding claims, characterized by receiving position data and determining the location using the received position data. Method according to one of the preceding claims, characterized in that determining the atmospheric pressure _patm includes determining a site altitude hs and calculating the atmospheric pressure patm using a predetermined functional relationship between atmospheric pressure _patm and site altitude hs. Method according to one of the preceding claims, characterized by detecting or receiving a location temperature T _s and determining the atmospheric pressure patm based on the location temperature T _s . procedure after claim 5 , if referred back to claim 4 , characterized in that the predetermined functional relationship is a functional relationship between atmospheric pressure patm, site altitude h _s and site temperature T _s . Method according to one of the preceding claims, characterized in that the atmospheric pressure p _atm is determined by means of an atmospheric pressure characteristic map, the atmospheric pressure characteristic map comprising predetermined atmospheric pressure values for specific positions. procedure after claim 7 , characterized in that the determination of the atmospheric pressure patm includes an interpolation between a plurality of predetermined atmospheric pressure values. procedure after claim 7 or 8th , if referred back to claim 5 , characterized in that the atmospheric pressure map is an atmospheric pressure-temperature map. Method according to one of the preceding claims, characterized in that the at least one air spring (1a) is part of an air spring system for leveling the vehicle axle (1). procedure after claim 10 , characterized by determining a level of the at least one air spring (1a) and determining the axle load acting on the vehicle axle (1), taking into account the determined level. Method according to one of the preceding claims, characterized in that the air-sprung vehicle axle (1) comprises a first and a second air spring (1a, 1b), the step of detecting involves detecting a first absolute air pressure pabs of the first air spring (1a) and a Detecting a second absolute air pressure pabs of the second air spring (1b) and determining the axle load on the basis of the detected first and second absolute air pressure pabs and the determined atmospheric pressure patm. procedure after claim 12 , characterized in that the first and second air springs (1a, 1b) are arranged at different points on the vehicle axle (1). Device (10) for axle load sensing, which is set up to carry out a method according to one of the preceding claims, having: - A sensor device (2) which is designed to detect an absolute air pressure pabs of the at least one air spring (1a); and - A determination device (3) which is designed to determine an atmospheric pressure patm based on a location of the vehicle axle (1) and to determine an axle load acting on the vehicle axle (1) on the basis of the detected absolute air pressure pabs and the determined atmospheric pressure patm. Vehicle (20), preferably commercial vehicle, having a device (10) for axle load sensing Claim 14 .

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