Method for operating an Anti-lock braking system of a vehicle, in particular a utility vehicle, computer program and / or computer-readable medium, control device and vehicle, in particular a utility vehicle

Abstract

The invention relates to a method (100) for operating, in relation to an axle (205), an anti-lock braking system (220) of a service brake (210) for braking a wheel (215) of the axle (205) of a vehicle (200a), in particular a utility vehicle (200b), wherein the method (100) comprises: detecting (110) a non-axle input variable (260); determining (120) a controlled variable (270) relating to the axle and / or to the wheel (215) of the axle (205) based on the non-axle input variable (260); and outputting (130) a control signal (280) for changing a braking variable (211) of the service brake (210), taking into account the controlled variable (270) relating to the axle and / or to the wheel (215) of the axle (205).

Description

[0001] Method for operating an anti-lock braking system of a vehicle, in particular a commercial vehicle, computer program and / or computer-readable medium, control unit and vehicle, in particular a commercial vehicle

[0002] The invention relates to a method for operating an anti-lock braking system of a service brake for braking a wheel of the axle of a vehicle, in particular a commercial vehicle, a computer program and / or computer-readable medium, a control device for a vehicle, in particular a commercial vehicle, and a vehicle, in particular a commercial vehicle.

[0003] Braking systems for vehicles with an anti-lock braking system (ABS) are known from the prior art. The braking system is designed to apply a braking torque to one or more wheels of the vehicle in order to decelerate the vehicle. ABS reduces or prevents the locking of a wheel braked by the braking system by reducing brake pressure, thus improving braking and driving safety.

[0004] ABS systems are known for detecting the speed of the wheel to be braked and, if the speed changes too abruptly, reducing the brake pressure in order to prevent or stop the wheel from locking.

[0005] Furthermore, centrally controlled braking systems are known which enable brake force distribution and / or vehicle dynamics control, for example using input signals from a yaw rate sensor.

[0006] DE 102018 123996 A1 discloses an at least two-channel electro-pneumatic central pressure control module designed as a structural unit for an electro-pneumatic service brake device of a vehicle, with at least two pressure control channels that can be electrically controlled with respect to a brake pressure.It is provided that a central electronic brake control unit has a circuit board carrying electrical and electronic components, wherein routines for at least brake pressure control and driving dynamics control are implemented in the electrical and electronic components, wherein at least one inertial sensor is arranged on or at the at least one circuit board and is electrically connected to at least some of the electrical and electronic components on the circuit board in such a way that the output signals of the at least one inertial sensor can be fed into the at least some electrical and electronic components for implementing driving dynamics control. Optionally, ABS pressure control valves can also be connected between the central pressure control module as the "central module" and brake cylinders on wheels of a first axle and a second axle, which allow wheel-individual control / regulation of the brake pressure in these brake cylinders.The central electronic brake control unit of the electropneumatic service brake system, which in addition to brake pressure control can also affect higher functions such as brake force distribution to the front and rear axle, vehicle dynamics control and / or brake slip control (ABS), is integrated into the central pressure control module.

[0007] The ABS pressure control valves are controlled by the central electronic brake control unit. A state-of-the-art anti-lock braking system for a wheel on an axle controls, regulates, and / or controls the braking of the wheel based on information relating to the wheel and / or axle itself, possibly influenced by an input signal from the central control unit.

[0008] However, such ABS control may lead to a shift in the axle load and a movement of the vehicle's driver's cab, particularly in the case of certain frictional characteristics of the road or the ground and special vehicle configurations.

[0009] Furthermore, it is noticeable that ABS pressure control valves, for example, are subject to increasingly stringent requirements regarding their cost-effectiveness. Improving ABS control can therefore offset the effects of such requirements and / or still improve the effectiveness of the ABS.

[0010] The invention is therefore based on the object of enriching the prior art. One embodiment achieves the object of providing improved performance of an ABS braking system and / or improving vehicle stability and / or reducing axle load shift and / or reducing movements of a driver's cab, thus improving safety and comfort.

[0011] This object is achieved by a method according to claim 1 and the subject matter according to the further independent claims. The subclaims specify further developments of the invention.

[0012] According to one aspect of the invention, a method is provided for the axle-related operation of an anti-lock braking system of a service brake for braking a wheel of the axle of a vehicle, in particular a commercial vehicle. The method comprises: detecting an input variable that is not related to the axle;

[0013] Determining an axle-related and / or axle-wheel-related control variable based on the non-axle input variable; and outputting a control signal for changing a braking variable of the service brake taking into account the axle-related and / or axle-wheel-related control variable.

[0014] The vehicle, in particular a commercial vehicle, is referred to below as the vehicle. The method is therefore a method for monitoring or controlling and / or regulating the vehicle's anti-lock braking system (ABS). For this purpose, the non-axle input variable is recorded. The non-axle input variable can be a variable relating to the vehicle but not, or not only, the axle with the wheel to be braked and / or a variable relating to another axle of the vehicle. The non-axle input variable can be recorded by sensors and / or by communication technology, for example via a vehicle bus and / or via an interface for vehicle-external communication. The input variable can comprise a plurality of different pieces of information. This enables comprehensive characterization of variables potentially relevant for braking.

[0015] The control variable can be determined based on the input variable. The control variable is a variable that relates to the axle with the wheel to be braked and / or to the wheel of the axle that is to be braked. The control variable can relate to the control of the braking of the wheel and / or the wheels of the axle. In other words, the control variable can be a wheel-specific control variable, particularly in the case of wheel-specific braking control.

[0016] Taking the control variable into account, the control signal can be output to change the braking force of the service brake. The braking force can be adjusted, for example, based on the control variable. The control signal can bring about a predictable change in the control variable. The braking force can be a variable that determines the braking torque of the wheel and / or wheels of the axle, which can be applied to the service brake via the control signal.

[0017] The invention provides an approach that enables the wheel and / or axle to be controlled with the ABS depending on information, data, or variables that are independent of or only indirectly dependent on the control of the wheel and / or axle. It was recognized that such a variable can typically describe vehicle dynamics, an environment, and / or other circumstances and / or characteristics that can influence the control of the ABS. Such an approach can also be applied with reference to automated driving functions and / or applications for autonomous driving, since in these cases, meaningful input variables are typically already detected and / or processed by the vehicle.

[0018] The method can be applied to each individual wheel, i.e., to only one wheel on the axle. Alternatively or additionally, the method can be applied to multiple wheels on the axle and / or to multiple wheels in an axle package comprising multiple axles.

[0019] Optionally, the control signal includes a trigger signal for activating ABS control by the anti-lock braking system. This makes it possible to activate an ABS that has not been previously activated. Alternatively or additionally, the control signal includes a selection signal for selecting a control strategy for the anti-lock braking system. This makes it possible to selectively transition control by the ABS from an already ongoing control according to one control strategy to control according to a different strategy. Alternatively or additionally, the control signal includes an input signal for determining the change in the braking variable. This makes it possible to change the intensity of the braking control by the ABS, for example as a braking variable of a braking force, a braking torque and / or a braking pressure.

[0020] Optionally, the control signal is output in such a way that the braking magnitude is changed alternatively, in addition to, and / or alternately with ABS control by the anti-lock braking system. This makes it possible for the braking magnitude adjustment by the ABS to be replaced or changed by the control signal. The replacement and / or change can occur alternately, i.e., alternately, for example, periodically. In other words, intervention in the ABS can occur independently of the ABS or in combination with the ABS by changing or influencing the ABS control.

[0021] Optionally, the control signal can be output in such a way that the change in braking force and ABS control by the anti-lock braking system are overlaid. This enables a transition between the change in braking force and ABS control. For example, priority can be given to the change in braking force by the control signal or to ABS control depending on a pressure reduction in order to reliably prevent the wheel from locking. This overlaid control can achieve a balance between the shortest possible braking distance and stable driving dynamics. ABS control can optionally be given priority in order to comply with legal and / or standardized requirements.

[0022] Optionally, the non-axle input variable comprises a driving dynamics variable and / or sensor data from a driving dynamics control system. The driving dynamics variable and / or sensor data relate to information, data or variables of another wheel on another axle, whereby the other axle is different from the axle with the wheel to be braked. The non-axle input variable can in particular comprise a yaw rate, a pitch rate, a wheel speed of a wheel not on the axle, an axle load of a wheel not on the axle, a normal force acting between another wheel on another axle and a surface and / or a friction coefficient between the other wheel of the other axle and the surface. The yaw rate of the vehicle, the pitch rate of the vehicle, the wheel speed, the axle load and the normal force can be measured by sensors and are variables that influence and / or reflect the driving dynamics, i.e. driving dynamics variables.Wheel slip can be calculated based on wheel speeds. The friction coefficient, as a driving dynamics parameter, provides information about the achievable slip.

[0023] Optionally, the non-axle input variable comprises operating data of the vehicle, in particular of a commercial vehicle. The vehicle operating data can, for example, include data that can be retrieved via a vehicle bus. The operating data can be based on operation by the driver and / or by an automated driving function. Alternatively or additionally, the non-axle input variable comprises an environmental variable relating to the surroundings of the vehicle, in particular of a commercial vehicle. In particular, the environmental variable can characterize properties of the subsurface or road surface. The environmental variable can be determined by sensors and / or retrieved externally from the vehicle. The environmental variable can, for example, include a road gradient and / or a coefficient of friction of the road surface. Alternatively or additionally, the non-axle input variable relates to a driving situation. This can make braking dependent, for example, on whether a dangerous situation exists.The aforementioned data or variables can be evaluated in combination. For example, a windshield wiper signal as operating data, combined with a low temperature as an ambient variable, can indicate a slippery road surface, i.e., a road surface with a low coefficient of friction.

[0024] Optionally, the axle-related and / or wheel-related control variable comprises a predicted wheel speed, a predicted slip limit, a predicted friction coefficient and / or a predicted normal force between the wheel and a surface. The control variable can therefore comprise information relating to the wheel and / or the axle which can be decisive for safety and / or driving comfort. According to one aspect of the invention, a computer program and / or a computer-readable medium is provided. The computer program and / or the computer-readable medium comprise instructions which, when the program or instructions are executed by a computer, cause the computer to carry out the method according to the invention and / or steps thereof. Optionally, the computer program and / or the computer-readable medium comprises instructions which, when the program or instructions are executed, cause the computer to carry out the method according to the invention and / or steps thereof.the instructions given by a computer cause it to carry out the process steps described as advantageous or optional in order to achieve an associated technical effect.

[0025] According to one aspect of the invention, a control unit for a vehicle, in particular a commercial vehicle, is provided. The control unit is configured to carry out the method described above. Optionally, the control unit is configured to carry out the method in such a way that one or more of the features described above as optional are implemented in order to achieve an associated technical effect.

[0026] According to one aspect of the invention, a vehicle, in particular a commercial vehicle, comprising a service brake with an anti-lock braking system and the control unit described above is provided. The control unit may have one or more features described as optional in order to achieve an associated technical effect.

[0027] Further advantages and features of the invention as well as its technical effects emerge from the figures and the description of the preferred embodiments shown in the figures.

[0028] Fig. 1 is a schematic representation of a vehicle, in particular a commercial vehicle, according to an embodiment of the invention;

[0029] Fig. 2 is a schematic representation of a flow chart of a method according to an embodiment of the invention; and

[0030] Fig. 3 is a schematic representation of a temporal development of various variables relating to a vehicle, in particular a commercial vehicle, when operating an anti-lock braking system according to the prior art compared with corresponding variables when operating an anti-lock braking system according to a method according to an embodiment of the invention.

[0031] Figure 1 shows a schematic representation of a vehicle 200a, in particular commercial vehicle 200b, of an embodiment of the invention.

[0032] The vehicle 200a, in particular the commercial vehicle 200b, is referred to below as the vehicle 200a, 200b. The vehicle 200a, 200b is a land vehicle, for example, a tractor of a multi-unit commercial vehicle.

[0033] The vehicle 200a, 200b is arranged in an environment 310 on a surface 300 and is in a driving situation 266. The surface 300 is, for example, a roadway with possibly locally varying conditions. The condition of the surface 300 influences a coefficient of friction and thus the driving dynamics of the vehicle 200a, 200b and, in particular, the braking of the vehicle 200a, 200b.

[0034] The vehicle 200a, 200b comprises a plurality of axles 205, 205', for example, two axles 205, 205'. The vehicle 200a, 200b comprises a plurality of wheels 215, 215' assigned to the axles 205, 205', for example, two wheels 215, 215' per axle 205, 205'. In an embodiment not shown, the vehicle 200a, 200b has more than two axles 205, 205' and / or the vehicle 200a, 200b has more than two, for example, four, wheels 215, 215' on at least one of the axles 205, 205'.

[0035] The vehicle 200a, 200b is arranged with the wheels 215, 215' on the ground 300. This means that the wheels 215, 215' contact the ground 300. The wheels 215, 215' and the ground 300 are operatively connected to one another at a contact surface. A friction coefficient can be defined at the contact surface between the wheels 215, 215' and the ground 300, which characterizes the contact between the respective wheel 215, 215' and the ground 300. The friction coefficient can be different for each of the wheels 215, 215'. The vehicle 200a, 200b includes a service brake 210. The service brake 210 is a pneumatic, hydraulic, and / or electromechanical brake. The service brake 210 is configured to achieve a braking effect for braking the vehicle 200a, 200b. For this purpose, the service brake 210 is configured to decelerate a movement of the wheels 215, 215' or to control and / or regulate a deceleration of the movement of the wheels 215, 215'.The service brake 220 can apply a braking variable 211, for example, a braking torque, a braking force, and / or a braking pressure, to decelerate the wheel(s) 215, 215'. Driving and / or braking the vehicle 200a, 200b causes slippage at the wheels 215, 215'.

[0036] The service brake 210 includes an anti-lock braking system 220. The anti-lock braking system 220 is configured to detect a tendency of the wheels 215, 215' to lock and to prevent the wheels 215, 215' from locking and / or to reduce the tendency of the wheels 215, 215' to lock. For this purpose, the anti-lock braking system 220 is configured to intervene in the braking process and reduce the braking force 211 if, for example, a tendency to lock is detected.

[0037] The vehicle 200a, 200b comprises a control unit 250. The control unit 250 is configured to carry out the method 100 described with reference to Figure 2.

[0038] The control unit 250 according to Figure 1 is configured to detect an external input variable 260. The external input variable 260 relates, for example, to the vehicle 200a, 200b, the driving and / or braking of the vehicle 200a, 200b, the additional axle 205', and / or the additional wheels 215' of the additional axle 205'. The external input variable 260 includes a vehicle dynamics variable 262 and / or sensor data from a vehicle dynamics control system. For this purpose, the control unit 250 is connected to corresponding sensors, a vehicle bus, and / or a communication device for vehicle-external communication (not shown).Thus, the control unit 250 can include as input variable 260 in particular a yaw rate 263a of the vehicle 200a, 200b, a pitch rate 263b of the vehicle 200a, 200b, a wheel speed of the non-axle wheel 215', an axle load of the non-axle wheel 215', a normal force acting between the further wheel 215' of the further axle 205' and a ground 300 and / or a friction coefficient between the further wheel 215' of the further axle 205' and the ground 300. In particular, via the vehicle bus, the control unit 250 can retrieve operating data of the vehicle 200a, 200b, an environmental variable 264 relating to the environment 310 of the vehicle 200a, 200b and / or information relating to the driving situation 266 as non-axle input variable 260.

[0039] The control unit 250 is configured to determine an axle-related control variable 270 and / or related to the wheel 215 of the axle 205 based on the non-axle input variable 260. The axle-related control variable 270 includes a predicted wheel speed, a predicted slip limit, a predicted friction coefficient, and / or a predicted normal force between the wheel 215 and the ground 300.

[0040] The control unit 250 is configured to output a control signal 280 to the service brake 210 for changing the braking variable 211 of the service brake 210, taking into account the axle-related control variable 270. The control signal 280 includes a trigger signal 282 for activating ABS control by the anti-lock braking system 220, a selection signal 284 for selecting a control strategy for the anti-lock braking system 220, and an input signal 286 for determining the change in the braking variable 211. The control signal 280 is output such that the change in the braking variable 211 occurs alternatively, in addition to, and / or alternately with ABS control by the anti-lock braking system 220. The control signal 280 is output such that the change in the braking variable 211 and ABS control by the anti-lock braking system 220 are overlapped.

[0041] The vehicle 200a, 200b is thus configured to control an anti-lock braking system 220 of a steerable front axle, here axle 205, based on sensor data from a vehicle dynamics control system (electronic stability program - ESC). For example, in a multi-directional split scenario, i.e., with different friction coefficients of the wheels 215 of axle 205, the yaw rate 263a can be used to adjust the braking variable 211. According to the prior art, typically only data relating to axle 205, such as pressure and / or wheel speed of wheel 215, was used.

[0042] The vehicle 200a, 200b is further configured to reduce and / or prevent potential negative effects of an axle load shift. A significant axle load shift can cause a wheel 215, 215' to abruptly drop, i.e., an excessive and undesirable increase in slip, for example, due to a decreasing normal force acting on the wheel 215, 215'. If the axle load shift is too significant, a prior art braking system may not be able to provide the required pressure reduction quickly enough, thus further amplifying the axle load shift. The vehicle 200a, 200b according to Figure 1 is configured to keep the braking force 211 for the front axle 205 constant or to reduce it when the other wheel 215' of the other axle 205', i.e., the rear axle, drops. This can counteract a subsequent rearward axle load shift from the wheel 215 of the front axle 205.Alternatively or additionally, the control unit 250 is configured to calculate a model for the axle load shift, to predict the axle load shift, and to change the braking variable 211 according to a prediction of the axle load shift.

[0043] The vehicle 200a, 200b is configured to perform automated driving functions. This allows the vehicle 200a, 200b to acquire information about the ground 300 along a trajectory to be traveled from other vehicles that have already traveled the trajectory. Based on the data external to the vehicle and relating to the ground 300, a change in the road surface properties, and in particular the friction coefficients, along the trajectory can be predicted, and based on a prediction of the friction coefficients along the trajectory, the braking variable 211 can be adjusted.

[0044] Figure 2 shows a schematic representation of a flowchart of a method 100 according to an embodiment of the invention. The method 100 is a method 100 for operating an anti-lock braking system 220 of a service brake 210 relative to an axle 205 for braking a wheel 215 of the axle 205 of a vehicle 200a, in particular a commercial vehicle 200b. Such a vehicle 200a, 200b is described with reference to Figure 1. Figure 2 is described with reference to Figure 1.

[0045] According to Figure 2, the method 100 comprises: detecting 110 an input variable 260 that is not related to the axle. The input variable 260 that is not related to the axle comprises a driving dynamics variable 262 and / or sensor data of a driving dynamics control system, in particular a yaw rate 263a, a pitch rate 263b, a wheel speed of a wheel 215' that is not related to the axle, an axle load of a wheel 215' that is not related to the axle, a normal force acting between a wheel 215' of a further axle 205' and a ground 300 and / or a friction coefficient between the wheel 215' of the further axle 205' and the ground 300. The input variable 260 that is not related to the axle comprises operating data of the vehicle 200a, in particular commercial vehicle 200b, an environment 310 of the vehicle 200a, in particular commercial vehicle 200b, Environmental variable 264 and / or relates to a driving situation 266.

[0046] A control variable 270 related to the axle and / or to the wheel 215 of the axle 205 is determined 120 based on the non-axle input variable 260. The control variable 270 related to the axle and / or to the wheel 215 of the axle 205 comprises a predicted wheel speed, a predicted slip limit, a predicted friction coefficient and / or a predicted normal force between the wheel 215 and the ground 300.

[0047] A control signal 280 is output 130 for changing a braking variable 211 of the service brake 210, taking into account the control variable 270 related to the axle and / or to the wheel 215 of the axle 205. The control signal 280 comprises a trigger signal 282 for activating ABS control by the anti-lock braking system 220, a selection signal 284 for selecting a control strategy for the anti-lock braking system 220, and / or an input signal 286 for determining the change in the braking variable 211. The control signal 280 is output such that the change in the braking variable 211 occurs alternatively, additionally, and / or alternately to ABS control by the anti-lock braking system 220. The control signal 280 is output such that the change in the braking variable 211 and ABS control by the anti-lock braking system 220 are superimposed.

[0048] Figure 3 shows a schematic representation of a temporal development of various variables relating to a vehicle 200a, in particular commercial vehicle 200b, during operation of an anti-lock braking system 220' according to the prior art, compared with corresponding variables during operation of an anti-lock braking system 220 according to a method 100 according to an embodiment of the invention. Such a vehicle 200a or commercial vehicle 200b is described with reference to Figure 1, and such a method 100 is described with reference to Figure 2. Figure 3 is described with reference to Figures 1 and 2.

[0049] Figure 3 is divided into five sections (A), (B), (C), (D), and (E). In each of the sections (A), (B), (C), (D), and (E), a variable is plotted as a function of time t. The time axis is scaled such that Figure 3 illustrates a braking process of the vehicle 200a, 200b.

[0050] The variables when operating an anti-lock braking system 220 according to a method 100 according to an embodiment of the invention are each illustrated by a solid line. The variables when operating an anti-lock braking system 220' according to the prior art differ in sections, in particular by dashed lines, from variables when operating an anti-lock braking system 220 according to a method 100 according to an embodiment of the invention. The variables when operating an anti-lock braking system 220' according to the prior art are each illustrated by a dashed line.

[0051] Section (A) shows a dependence of a speed V on time t. The upper solid line shows a vehicle speed VV, i.e., the speed V of the vehicle 200a or commercial vehicle 200b. Partially deviating from the vehicle speed VV, the wheel speed VW, VW of the wheel 215 of the vehicle 200a or commercial vehicle 200b is shown, i.e., the wheel 215 on whose axle 205 the anti-lock braking system 220, 220' acts. The wheel speed VW is related to an anti-lock braking system 220 according to a method 100 according to one embodiment of the invention. The wheel speed VW is related to an anti-lock braking system 220' according to the prior art.

[0052] Section (B) shows a wheel acceleration AW, AW corresponding to the wheel speed VW of wheel 215, i.e., a time derivative of the wheel speed VW, VW. The wheel acceleration AW is related to an anti-lock braking system 220 according to a method 100 according to one embodiment of the invention. The wheel acceleration AW is related to an anti-lock braking system 220' according to the prior art.

[0053] Section (C) shows a dependence of a brake pressure p, p' on time t as an example of a braking variable 211 that is changed by an intervention by the anti-lock braking system 220, 220'. The brake pressure p is related to an anti-lock braking system 220 according to a method 100 according to one embodiment of the invention. The brake pressure p' is related to an anti-lock braking system 220' according to the prior art.

[0054] Section (D) shows a dependence on time t of a mode M of the anti-lock braking system 220 according to the invention or of an anti-lock braking system 220' according to the prior art as an exemplary control variable 270. The mode M indicates whether the anti-lock braking system 220' according to the prior art is being used or the anti-lock braking system 220 according to the method 100 according to the invention. In section (D), it is therefore shown as a binary variable. However, by blending the change in the braking variable 211 according to the method 100 according to the invention and an ABS control by the anti-lock braking system 220' according to the prior art, the mode M can also assume other values ​​(not shown). Furthermore, in addition or alternatively, a different control variable 270 can be defined instead of the mode M (see description of Figures 1 and 2).

[0055] Section (E) shows a dependence of a pressure request R, R' on time t as an exemplary control signal 280. The pressure request R, R' can assume three values ​​and control a reduction d of the braking variable 211, a maintenance h of the braking variable 211, or an increase i of the braking variable 211. However, the pressure request R, R' can also assume other values ​​(not shown). Furthermore, additionally or alternatively, another control signal 280 can be defined instead of the pressure request R (see description of Figures 1 and 2). The pressure request R relates to an anti-lock braking system 220 according to a method 100 according to an embodiment of the invention. The pressure request R' relates to an anti-lock braking system 220' according to the prior art.

[0056] As can be seen from the mode M and from the control signal 280 by the dashed lines VL1, VL2 extending vertically through sections (A), (B), (C), (D), and (E), the control signal 280 is output such that the change in the braking variable 211 occurs alternatively and in addition to ABS control by the anti-lock braking system 220. The ABS control by the anti-lock braking system 220 occurs outside the time period marked by the vertical lines, i.e., before the first vertical line VL1 and after the second vertical line VL2.In this case, the change in the braking variable 211 and the ABS control by the anti-lock braking system 220 also take place alternately: first, the ABS control by the anti-lock braking system 220 takes effect, thus the mode M corresponds to the anti-lock braking system 220' according to the prior art; then, according to the method 100 according to the invention, the change in the braking variable 211 takes effect, which is defined by the control signal 280 and can be seen from the mode M for the anti-lock braking system 220; and finally, the ABS control by the anti-lock braking system 220 takes effect as initially.

[0057] In the time period marked by the vertically extending dashed lines VL1, VL2, the ABS control by the anti-lock braking system 220 is replaced by changing the braking variable 211 according to the method 100 according to the invention; the changing of the braking variable 211 therefore occurs as an alternative to ABS control by the anti-lock braking system 220. With respect to the entire braking process, the changing of the braking variable 211 occurs in addition to ABS control by the anti-lock braking system 220, since before and after the changing of the braking variable 211, the ABS control by the anti-lock braking system 220 takes effect.

[0058] Sections (A) and (B) illustrate the effect of method 100 on wheel 215: while wheel 215 exhibits a continuous and repetitive drop in the anti-lock braking system 220' according to the prior art, i.e., a repetitive reduction in wheel speed VW relative to vehicle speed VV, wheel speed VW approaches vehicle speed VV in the case of changing braking variable 211 according to method 100. This is also reflected in wheel acceleration AW, AW, which continues to oscillate according to the prior art but remains constant according to the invention.

[0059] This is due to the brake pressure p, p' according to section (C). While the prior art involves an oscillating or alternating increase i and decrease d of the brake pressure p', the brake pressure p according to the invention is reduced and kept constant in the example. This is evident in the control signals 280 in section (E), according to which, in the example according to the invention, first a reduction d and then a holding h are controlled. In the prior art, the brake pressure p' would be reduced and increased alternately.

[0060] Reference symbol (part of the description)

[0061] 100 procedures

[0062] 110 Capture

[0063] 120 Investigate

[0064] 130 Issues

[0065] 200a vehicle

[0066] 200b commercial vehicle 205, 205' axle

[0067] 210 Service brake

[0068] 211 brake size

[0069] 215, 215' wheel

[0070] 220 Anti-lock braking system (after the invention)

[0071] 220' anti-lock braking system (according to the state of the art)

[0072] 250 control unit

[0073] 260 non-axis input variable

[0074] 262 Driving dynamics size

[0075] 263 Yaw rate

[0076] 264 Environment size

[0077] 266 Driving situation

[0078] 270 Control variable

[0079] 280 control signal

[0080] 282 trigger signal

[0081] 284 selection signal

[0082] 286 input signals

[0083] 300 underground

[0084] 310 surroundings

[0085] AW wheel acceleration (after invention)

[0086] AW Wheel acceleration (according to the state of the art) d Lower h Hold i Increase

[0087] M Mode p Brake pressure (according to the invention) p' Brake pressure (according to the prior art)

[0088] R pressure requirement (according to the invention)

[0089] R' pressure requirement (according to the state of the art) t time

[0090] V speed

[0091] VL1 first vertical line

[0092] VL2 second vertical line

[0093] W Vehicle speed

[0094] VW wheel speed (after invention)

[0095] VW wheel speed (according to the state of the art)

Claims

Patent claims 1 . Method (100) for operating an anti-lock braking system (220) of a service brake (210) for braking a wheel (215) of the axle (205) of a vehicle (200a), in particular a commercial vehicle (200b), with respect to an axle (205), the method (100) comprising: - detecting (110) an input variable (260) that is not related to the axis; - determining (120) a control variable (270) related to the axle and / or to the wheel (215) of the axle (205) based on the non-axle input variable (260); and - outputting (130) a control signal (280) for changing a braking variable (211) of the service brake (210) taking into account the control variable (270) related to the axle and / or to the wheel (215) of the axle (205).

2. The method (100) according to claim 1, wherein the control signal (280) comprises a trigger signal (282) for activating ABS control by the anti-lock braking system (220), a selection signal (284) for selecting a control strategy for the anti-lock braking system (220) and / or an input signal (286) for determining the change in the braking quantity (211).

3. Method (100) according to claim 1 or 2, wherein the control signal (280) is output such that the change in the braking variable (211) occurs alternatively, additionally and / or alternately to an ABS control by the anti-lock braking system (220).

4. Method (100) according to one of the preceding claims, wherein the control signal (280) is output such that the change in the braking variable (211) and an ABS control by the anti-lock braking system (220) are superimposed.

5. Method (100) according to one of the preceding claims, wherein the non-axle input variable (260) comprises a driving dynamics variable (262) and / or sensor data of a driving dynamics control system, in particular a yaw rate (263a), a pitch rate (263b), a wheel speed of a non-axle wheel (215'), an axle load of a non-axle wheel (215'), a normal force acting between a further wheel (215') of a further axle (205') and a ground (300) and / or a friction coefficient between the further wheel (215') of the further axle (205') and the ground (300).

6. Method (100) according to one of the preceding claims, wherein the non-axle input variable (260) comprises operating data of the vehicle (200a), in particular commercial vehicle (200b), comprises an environmental variable (264) relating to an environment (310) of the vehicle (200a), in particular commercial vehicle (200b), and / or relates to a driving situation (266).

7. The method (100) according to any one of the preceding claims, wherein the axle-related and / or wheel (215) of the axle (205)-related control variable (270) comprises a predicted wheel speed, a predicted slip limit, a predicted friction coefficient and / or a predicted normal force between the wheel (215) and a ground (300).

8. Computer program and / or computer-readable medium comprising instructions which, when the program or instructions are executed by a computer, cause the computer to carry out the method (100) and / or the steps of the method (100) according to one of the preceding claims.

9. Control unit (250) for a vehicle (200a), in particular a commercial vehicle (200b), wherein the control unit (250) is configured to carry out the method (100) according to one of claims 1 to 7.

10. Vehicle (200a), in particular a commercial vehicle (200b), comprising a service brake (210) with an anti-lock braking system (220) and the control unit (250) according to claim 9.

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