DE102020106757A1 - Method for determining a motor vehicle mass of a motor vehicle towing a trailer, computer program product and motor vehicle - Google Patents

Abstract

A method is described for determining a motor vehicle mass of a motor vehicle pulling a trailer, a total mass of a combination consisting of motor vehicle and trailer being determined, a force that the trailer introduces on the motor vehicle being measured by means of a force sensor arranged on a trailer coupling, an acceleration of the trailer combination being measured, a trailer mass being determined from the acceleration and force, the motor vehicle mass being determined by subtracting the trailer mass from the total mass of the trailer combination.

Description

A method for determining a motor vehicle mass of a motor vehicle pulling a trailer, a computer program product and a motor vehicle are described here.

Methods for determining a motor vehicle mass of a motor vehicle pulling a trailer, computer program products and motor vehicles of the type mentioned at the beginning are known in the prior art.

In some countries there are regulations or regulations are being discussed which require the mass of a motor vehicle to be recorded at any time. This serves in particular to avoid overloading motor vehicles and is therefore particularly relevant in commercial vehicles with a loading compartment. Furthermore, there are already similar regulations in some countries with regard to trailers, the mass of which should also be able to be recorded.

In principle, it is possible to measure the motor vehicle mass statically and / or dynamically, for example by means of voltage measurements, distance-based measurement systems on the chassis or the body, or by pressure measurement, for example in air spring components. Furthermore, dynamic systems are known that can use motor vehicle sensors and can calculate a motor vehicle mass therefrom.

In the case of combinations consisting of a motor vehicle and a trailer, in which the trailer is not equipped with a mass measurement system, it is not possible to measure the mass of the motor vehicle in isolation with dynamic systems. Only the total weight consisting of the vehicle mass and the trailer mass can be determined there.

From the US 2003/154798 A1 a weight monitoring system for a motor vehicle connected to a trailer is known. A pulling force can be determined by means of a force sensor placed in a trailer coupling, while another sensor determines the acceleration of the motor vehicle, a combination of these two parameters making it possible to calculate the mass of the trailer. A total mass of the vehicle is determined by pressure and / or distance sensors that are located in the suspension system.

The known systems provided in the motor vehicle, which are based on dynamic measurement methods, are not compatible with the new regulations, since they cannot determine the motor vehicle mass separately in a combination. Therefore, trailers without a mass measurement system can no longer be used in countries with corresponding regulations.

The object is thus to develop methods for determining a motor vehicle mass of a motor vehicle towing a trailer, computer program products and motor vehicles of the type mentioned at the outset in such a way that the motor vehicle mass can also be determined for trailers without a mass measurement system.

The object is achieved by a method for determining a motor vehicle mass of a motor vehicle pulling a trailer according to claim 1, a computer program product according to the independent claim 10 and a motor vehicle according to the independent claim 11. Further configurations and developments are the subject of the dependent claims.

A method for determining a motor vehicle mass of a motor vehicle pulling a trailer is described below, a total mass of a combination consisting of motor vehicle and trailer being determined, a force that the trailer introduces onto the motor vehicle being measured by means of a force sensor arranged on a trailer coupling. an acceleration of the trailer combination being measured, a trailer mass being determined from the acceleration and force, the motor vehicle mass being determined by subtracting the trailer mass from the total mass of the trailer combination.

The force sensor can be installed at various points on the trailer coupling. One possibility is to position the force sensor on a ball head of the trailer coupling. Another possibility is to place the force sensor on a connection between the trailer coupling and the motor vehicle. Furthermore, it is also possible to install between two components of the trailer coupling that are in the power flow.

The force sensor can have various designs. It can have a path-based measuring system, a piezo force sensor, an electrodynamic force sensor, a resistive force sensor. Other concepts are also conceivable, for example with spring bodies or oscillating elements.

In a first further refinement, it can be provided that the vehicle mass is determined when the trailer combination is in motion.

The method takes advantage of the fact that the mass of the trailer at a given acceleration causes a reaction force in the trailer coupling which is proportional to the mass of the trailer. In this way, the mass of the trailer can be determined by the acceleration force that the trailer creates on the trailer coupling. It has been shown that other frictional forces on the trailer are too small compared to the necessary acceleration force to render the result of the measurement unusable.

This enables dynamic measurement of the vehicle mass. Static mass measurement methods, which usually require at least one force transducer per axle or even per wheel and are therefore more expensive to implement and, in particular, cannot be retrofitted or can only be retrofitted with great difficulty, are not required.

In a further refinement, it can be provided that the acceleration is a positive acceleration.

In this way, influences from the braking systems of a braked trailer can be avoided.

In a further refinement, it can be provided that the acceleration is a negative acceleration.

Since negative accelerations are usually greater than positive accelerations in commercial vehicles, greater forces can be generated and thus more accurate measurement results.

In a further refinement, it can be provided that a braking device of the trailer is not activated.

In this way, the vehicle mass can also be determined when the trailers are braked.

In a further refinement, it can be provided that the force is a tensile or compressive force.

In this way, the influence of the bearing force of a drawbar of the trailer on the trailer coupling which falsifies the measurement result can be eliminated.

In a further refinement, it can be provided that the total mass of the combination is determined by means of a brake control module and / or an active chassis control module.

Most motor vehicles have brake control modules that are already equipped with accelerometer sensors in many motor vehicles. The use of corresponding brake control modules therefore enables the use of already provided components of the motor vehicle without additional components or sensors being required for the acceleration measurement.

Chassis control modules also often already have acceleration measurement sensors.

In a further refinement, it can be provided that the acceleration is determined by means of a brake control module and / or an active chassis control module.

In most cases, acceleration measuring sensors are already provided here, and the data can be accessed.

Chassis control modules also often already have acceleration measurement sensors.

In a further refinement, it can be provided that the trailer does not have a mass detection system.

With the aid of the method presented here, it is possible to use trailers without a mass detection system even in countries in which a motor vehicle mass and / or a trailer mass must be known.

A first independent subject relates to a device for determining a motor vehicle mass of a motor vehicle pulling a trailer, with a device for determining a total mass of a combination consisting of motor vehicle and trailer, and a force sensor arranged on a trailer coupling for measuring a force that the trailer exerts on the Motor vehicle initiates, wherein means are provided for measuring an acceleration of the trailer combination, wherein means are provided to determine a trailer mass from acceleration and force, wherein means are provided to determine the motor vehicle mass by subtracting the trailer mass from the total mass of the trailer combination.

In a first further refinement, it can be provided that the device is set up to determine the vehicle mass when the trailer combination is in motion.

In a further refinement, it can be provided that the acceleration is a positive acceleration.

In a further refinement, it can be provided that the acceleration is a negative acceleration.

In a further refinement, it can be provided that the trailer has a braking device which can be deactivated to determine the trailer mass.

In a further refinement, it can be provided that the force is a tensile or compressive force.

In a further refinement, provision can be made for a brake control module and / or an active chassis control module to be provided for determining the total mass of the combination.

In a further refinement, it can be provided that a brake control module and / or an active chassis control module is provided for determining an acceleration of the combination.

In a further refinement, it can be provided that the trailer does not have a mass detection system.

Another independent subject matter relates to a computer program product with a computer-readable storage medium on which instructions are embedded which, when executed by at least one processing unit, have the effect that the at least processing unit is set up to carry out the method of the aforementioned type.

The method can be carried out distributed on one or more processing units, so that certain method steps are carried out on one processing unit and other method steps are carried out on at least one further processing unit, with calculated data being able to be transmitted between the processing units if necessary.

Another independent subject matter relates to a motor vehicle with a computer program product of the type described above.

In a first further refinement, it can be provided that a controller with a computing unit and a computer-readable storage medium.

In a further refinement, a force sensor which is arranged on the trailer coupling and measures tensile forces and / or compressive forces and is connected to the controller can be provided.

In a further refinement, a brake control module connected to the controller and / or a chassis control module connected to the controller can be provided.

• 1 eine Seitenansicht eines Gespanns mit einem Kraftfahrzeug und einem Anhänger;
• 2 ein System zur Bestimmung einer Kraftfahrzeugmasse, sowie
• 3 ein Ablaufdiagramm eines Verfahrens zur Bestimmung einer Kraftfahrzeugmasse.

Further features and details emerge from the following description, in which at least one exemplary embodiment is described in detail - possibly with reference to the drawing. Described and / or graphically represented features form the subject matter individually or in any meaningful combination, possibly also independently of the claims, and can in particular also be the subject matter of one or more separate applications. Identical, similar and / or functionally identical parts are provided with the same reference symbols. They show schematically:

• 1 a side view of a combination with a motor vehicle and a trailer;
• 2 a system for determining a vehicle mass, as well as
• 3 a flowchart of a method for determining a motor vehicle mass.

1 shows a team 2 with a motor vehicle 4th and a trailer 6th .

The trailer 6th is via a trailer coupling 8th on the motor vehicle 4th attached. The trailer 6th does not have its own device for determining its trailer mass mA on. The trailer hitch 8th assigns an in 1 force measuring sensor, not shown.

The team 2 has a total mass mG on, consisting of a motor vehicle mass mF and a trailer mass mA made up of: mG = mF + mA. In some countries it is necessary to measure the vehicle mass mF and / or the trailer mass mA to be determined separately.

The total mass mG can be done with the help of dynamic sensors in the motor vehicle 4th , for example by means of a brake control module (in 1 not shown).

The trailer mass mA can be derived from the general force equation when an acceleration a of the team 2 as well as a force fa on the trailer coupling 8th it is known: mA = fA * a.

The trailer mass can therefore be obtained from both measurements mA and on the other hand a vehicle mass mF to be determined separately.

2 shows a system 10 (framed by dashed lines) to determine the vehicle mass mF .

The system 10 has a brake control module 12th on that one arithmetic unit 14th as well as one to the arithmetic unit 14th connected, computer-readable storage medium 16 has, on which a computer program product is stored that carries out the method described here when it is from the computing unit 14th is loaded and running.

The brake control module 12th furthermore has an acceleration sensor 18th on, the one with the arithmetic unit 14th connected is. Using the accelerometer 18th can accelerate the motor vehicle 4th and thus the team 2 be measured. Using the accelerometer 18th In addition to the use described here, braking interventions can also be regulated, among other things by adapting a brake pressure in order to achieve a target deceleration.

The brake control module 12th is also with one on the trailer hitch 8th arranged force measuring sensor 20th tied together. The force measuring sensor 20th can measure tensile and compressive forces. The force measuring sensor 20th is in the present case designed as a piezo sensor, which is attached to a connection of the trailer coupling 8th on a body of the motor vehicle 4th is arranged. This allows tensile and compressive forces between the body and the trailer coupling 8th transmitted, measured.

The brake control module 12th can be the total mass mG of the team 2 determine by delaying the team 2 is set in relation to a necessary braking force to achieve the deceleration.

3 shows a flow chart of the method.

After starting the procedure, the accelerometer is used 18th of the brake control module 12th checked whether the team 2 accelerated.

Only when this is the case will the acceleration a by means of the acceleration sensor 18th from the arithmetic unit 14th read out. Furthermore, the total mass of the trailer combination is determined using the brake control module 12th certainly.

In a further step, the force sensor of the trailer coupling is read out and the reaction force fa of the trailer 6th determined on the same size, but directed in the opposite direction tensile force.

From the reaction force fa of the trailer 6th and acceleration a lets the trailer mass mA determine: $$\text{mA = fA * a}.$$

The vehicle mass can be calculated by subtracting the trailer mass mA of the total mass mG determine: $$\text{mF = mG-mA}.$$

Although the subject matter was illustrated and explained in more detail by means of exemplary embodiments, the invention is not restricted by the disclosed examples and other variations can be derived therefrom by the person skilled in the art. It is therefore clear that there is a multitude of possible variations. It is also clear that embodiments cited by way of example only represent examples which are not to be interpreted in any way as a limitation, for example, of the scope of protection, the possible applications or the configuration of the invention. Rather, the preceding description and the description of the figures enable the person skilled in the art to specifically implement the exemplary embodiments, whereby the person skilled in the art, with knowledge of the disclosed inventive concept, can make various changes, for example with regard to the function or the arrangement of individual elements mentioned in an exemplary embodiment, without the To leave the scope of protection that is defined by the claims and their legal equivalents, such as a more detailed explanation in the description.

List of reference symbols

2

Team

4th

Motor vehicle

6th

pendant

8th

trailer hitch

10

system

12th

Brake control module

14th

Arithmetic unit

16

Storage medium

18th

Accelerometer

20th

Force measuring sensor

a

acceleration

fa

force

mA

Trailer mass

mF

Vehicle mass

mG

Total mass

QUOTES INCLUDED IN THE DESCRIPTION

This list of the documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent literature cited

• US 2003154798 A1 [0006]

Claims (14)

A method for determining a motor vehicle mass (mF) of a motor vehicle (4) pulling a trailer (6), a total mass (mG) of a combination (2) consisting of motor vehicle (4) and trailer (6) being determined, using one on a Trailer coupling (8) arranged force sensor (20) a force (fA) which the trailer (6) introduces onto the motor vehicle (4) is measured, an acceleration (a) of the combination (2) being measured, with acceleration ( a) and force (fA) a trailer mass (mA) is determined, the motor vehicle mass (mF) being determined by subtracting the trailer mass (mA) from the total mass (mG) of the combination (2). Procedure according to Claim 1 , whereby the determination of the vehicle mass (mF) is carried out when the trailer combination (2) is in motion. Procedure according to Claim 1 or 2 , where the acceleration is a positive acceleration (a). Procedure according to Claim 1 or 2 , where the acceleration is a negative acceleration. Procedure according to Claim 4 , wherein a braking device of the trailer (6) is not activated. Method according to one of the preceding claims, wherein the force is a tensile or compressive force. Method according to one of the preceding claims, wherein the total mass of the combination is determined by means of a brake control module (18) and / or an active chassis control module. Method according to one of the preceding claims, wherein the acceleration (a) is determined by means of a brake control module (18) and / or an active chassis control module. Method according to one of the preceding claims, wherein the trailer (6) does not have a mass detection system. Computer program product with a computer-readable storage medium (16) on which instructions are embedded which, when executed by at least one computing unit (14), have the effect that the at least one computing unit (14) is set up to implement the method according to one of the preceding To carry out claims. Motor vehicle with a computer program product Claim 10 . Motor vehicle after Claim 11 , with a controller (12) with a computing unit (14) and a computer-readable storage medium (16). Motor vehicle after Claim 11 or 12th with a force sensor (20) which is arranged on the trailer coupling (8) and measures tensile forces and / or compressive forces and is connected to the controller (12). Motor vehicle according to one of the Claims 11 until 13th , with a brake control module (18) connected to the controller (12) and / or a chassis control module connected to the controller (12).

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