Control unit for a vehicle, steering actuator for a vehicle, vehicle, method for a vehicle, and computer program

Abstract

A control unit for a vehicle is proposed. The control unit comprises an interface for communication with a first steering axle and a second steering axle. The control unit also comprises a data processing circuit designed to control the interface. The data processing circuit is also designed to obtain a target parameter indicative of a target steering angle of the vehicle and to determine a first control parameter for the first steering axle. The first control parameter is determined on the basis of the target parameter. The first control parameter is indicative of a parameter for controlling an electromechanical steering axle. The data processing circuit is also designed to determine a second control parameter for the second steering axle on the basis of the target parameter. The second control parameter is indicative of a parameter for controlling an electromechanical steering axle, a parameter for controlling a pneumatic steering axle and / or a parameter for controlling an electrohydraulic steering axle. The data processing circuit is also designed to transmit the first control parameter in order to adjust an orientation of the first steering axle and to transmit the second control parameter in order to adjust an orientation of the second steering axle.

Description

[0001] Control unit for a vehicle, steering actuator for a vehicle, vehicle, method for a vehicle and computer program

[0002] The present invention relates to a control unit for a vehicle, a steering actuator for a vehicle, a vehicle, a method for a vehicle and a computer program.

[0003] The simultaneous coordination of steered axles in a vehicle is a challenging task due to the complex interaction of multiple steering mechanisms. Different axles must be precisely coordinated to avoid undesirable effects such as oversteer or understeer and to maintain vehicle stability. Precise control of individual axles may be particularly necessary when different axle types interact.

[0004] Against this background, it is an object of the present invention to enable improved control of a plurality of steering axles, wherein at least one steering axle is an electromechanical steering axle.

[0005] The object of the invention is achieved by a control unit for a vehicle, a steering actuator for a vehicle, a vehicle, a method for a vehicle, and a computer program according to the independent claims. Further aspects and developments of the invention are set forth in the dependent claims, the following description, and the figures.

[0006] According to a first aspect of the invention, a control unit for a vehicle is proposed. The control unit comprises an interface for communication with a first steering axle and a second steering axle. The control unit further comprises a data processing circuit configured to control the interface. The data processing circuit is further configured to receive a target parameter indicative of a target steering angle of the vehicle and to determine a first control parameter for the first steering axle. The first control parameter is determined based on the target parameter. The first control parameter is indicative of a parameter for controlling an electromechanical steering axle. The data processing circuit is further configured to determine a second control parameter for the second steering axle based on the target parameter.The second control parameter is indicative of a parameter for controlling an electromechanical steering axle, a parameter for controlling a pneumatic steering axle, and / or a parameter for controlling an electrohydraulic steering axle. The data processing circuit is further configured to send the first control parameter for adjusting an orientation of the first steering axle and to send the second control parameter for adjusting an orientation of the second steering axle. By determining the first control parameter and the second control parameter, a plurality of steering axles comprising an electromechanical steering axle can be controlled. In particular, the plurality of steering axles can be controlled simultaneously. As a result, a vehicle comprising an electromechanical steering axle can be controlled by means of the control unit.The control of the vehicle by means of the control unit can be carried out based on the received target parameter.

[0007] In one embodiment, the first control parameter can be indicative of cascade control of the electromechanical steering axle and / or indicative of torque control of an electric motor of an electromechanical steering axle. The first control parameter can therefore be specifically suited for controlling an electromechanical steering axle. For example, controlling an electrohydraulic steering axle may not be possible with the first control parameter. The first control parameter can therefore be specific to an electromechanical steering axle. This can enable control of a vehicle comprising an electromechanical steering axle. In particular, the electromechanical steering axle can be a main steering axle of the vehicle.

[0008] In one embodiment, the data processing circuit can be configured to receive a mode parameter indicative of an operating mode of the vehicle. The data processing circuit can be configured to determine the first control parameter and the second control parameter based on the mode parameter. By receiving the mode parameter, the first control parameter and the second control parameter can be adapted to an operating mode of the vehicle. For example, the vehicle can have different operating modes, e.g., crab steering or central steering. Accordingly, the first control parameter and the second control parameter can be determined for a specific, e.g., a selected, operating mode. As a result, an alignment of the plurality of steering axes can be adapted to an operating mode of the vehicle.

[0009] In one embodiment, the data processing circuit can be configured to receive a braking parameter indicative of a status of a braking system of the vehicle. Furthermore, the data processing circuit can be configured to determine the first control parameter and the second control parameter based on the braking parameter. For example, a function of a braking system of the vehicle may be limited. Accordingly, additional braking by the plurality of steering axles may be required or desired. Based on the braking parameter, a need for braking by the plurality of steering axles can be determined. As a result, a braking process of the vehicle can be improved by aligning the plurality of steering axles.

[0010] In one embodiment, the data processing circuit can be configured to receive a driving assistance parameter indicative of a limitation of the maneuverability of the vehicle. Furthermore, the data processing circuit can be configured to determine the first control parameter and the second control parameter based on the driving assistance parameter. For example, the maneuverability of the vehicle can be limited by the vehicle's surroundings. Accordingly, the alignment of the plurality of steering axes cannot be arbitrarily performed. By receiving the driving assistance parameter, the maneuverability of the vehicle, for example, the vehicle's surroundings, can be taken into account when determining the first control parameter and / or the second control parameter. This can improve control of the vehicle.

[0011] In one embodiment, the first control parameter can be used to adapt the orientation of the first steering axis to a first steering angle. The second control parameter can be used to adapt the orientation of the second steering axis to a second steering angle. The first steering angle can be different from the second steering angle. This allows for mechanical decoupling of the first steering axis from the second steering axis, for example, during crab walking. This can improve vehicle control.

[0012] According to a second aspect of the invention, a steering actuator for a vehicle comprising a control unit as described above is proposed. The steering actuator can, in particular, be a steering actuator of a main steering axle. The control unit can thus be included in a steering actuator of a steering axle. This can simplify the design of the vehicle's electrical system.

[0013] According to a third aspect of the invention, a vehicle with a control unit as described above or a steering actuator as described above is proposed. In a vehicle, the control unit offers the advantage that a plurality of steering axles of the vehicle can be controlled by means of the control unit. For example, only one steering axle of the vehicle, for example the main steering axle, needs to include a control unit. This one control unit can then assume control of the plurality of steering axles of the vehicle. All steering axles of the vehicle (including an electromechanical steering axle) can thus be controlled by means of just one control unit. In particular, the orientation of a steering axle can be controlled via a corresponding actuator of the steering axle.For example, the alignment of an electromechanical steering axle can be carried out by an electromechanical steering actuator, the alignment of an electrohydraulic steering axle via an electrohydraulic steering actuator, the alignment of a pneumatic steering axle via a pneumatic steering actuator.

[0014] According to a fourth aspect of the invention, a method for a vehicle is proposed. The method comprises obtaining a target parameter indicative of a target steering angle of the vehicle. The method further comprises determining, based on the target parameter, a first control parameter for the first steering axle. The first control parameter is indicative of a parameter for controlling an electromechanical steering axle. The method further comprises determining, based on the target parameter, a second control parameter for the second steering axle. The second control parameter is indicative of a parameter for controlling an electromechanical steering axle, a parameter for controlling a pneumatic steering axle, and / or a parameter for controlling an electrohydraulic steering axle.The method further comprises sending the first control parameter to adjust an orientation of the first steering axis and sending the second control parameter to adjust an orientation of the second steering axis.

[0015] According to a fifth aspect of the invention, a computer program is proposed. The computer program is designed to perform one of the methods described above when the computer program runs on a computer, a processor, or a programmable hardware component.

[0016] The present invention will be described below by way of example only, with reference to the accompanying figures. They show:

[0017] Figs. 1a and 1b show schematic representations of a control unit and a steering actuator of a vehicle comprising a control unit;

[0018] Fig. 2 shows a schematic view of a vehicle; and

[0019] Fig. 3 shows a block diagram of an embodiment of a method.

[0020] Figs. 1a and 1b show schematic representations of a control unit 130 and a steering actuator of a vehicle comprising a control unit 130.

[0021] Fig. 1a shows a block diagram of an embodiment of a control unit 130 for a vehicle. The control unit 130 includes an interface 134 for communication with a first steering axle and a second steering axle. The control unit 130 further includes a data processing circuit 132. The data processing circuit 132 is configured to control the interface 134. The data processing circuit 132 is configured to receive a target parameter indicative of a target steering angle of the vehicle. The target steering angle in a vehicle can refer to the desired or predetermined angle by which the wheels of a steering axle of a vehicle should rotate when it is steered. The target steering angle is normally measured in degrees and determines how strongly the vehicle is steered in a certain direction when the driver turns the steering wheel.

[0022] The target parameter can be indicative of a total steering angle of the vehicle. For example, the target steering angle can be a total steering angle of the vehicle. This means that the target steering angle can specify a trajectory of the vehicle. For example, a resulting trajectory can be determined from the total steering angle, for example, by the control unit 130.

[0023] Optionally, the vehicle's trajectory can be defined by multiple axle-specific target steering angles. The vehicle's total steering angle can therefore be composed of a plurality of axle-specific target steering angles of the individual steering axles of the vehicle's plurality of steering axles. This means that the target parameter or the target steering angle can include or be indicative of a plurality of axle-specific target steering angles. Accordingly, the target parameter can be indicative of a plurality of axle-specific target steering angles. The trajectory can then result from the axle-specific target steering angles.

[0024] Optionally or alternatively, the target parameter for using a virtual driver can also be indicative of a vehicle trajectory. For example, the virtual driver can specify a trajectory for the vehicle. Based on the specified trajectory, a target steering angle can then be determined. For example, the control unit 130 can receive trajectory data about a vehicle trajectory from a driver assistance system. Based on the trajectory data, the control unit 130 can determine the target parameter.

[0025] The target parameter can be received by a steering device of the vehicle. For example, a driver of the vehicle can deflect the steering wheel. Based on the deflection of the steering wheel, the steering device can determine a target parameter. The determined target parameter can be sent from the steering device to the control unit 130. The control unit 130 can thus receive the target parameter.

[0026] Optionally or alternatively, the control unit 130 can determine the target parameter. For example, the control unit 130 can receive data about a deflection of the steering wheel of the vehicle. The data can be received, for example, from a steering device of the vehicle. Based on the data about the deflection of the steering wheel, the control unit 130 can determine the target steering angle. In particular, the control unit 130 can determine the plurality of axle-specific target steering angles. This means that the control unit 130 can receive data about a deflection of a steering wheel of the vehicle, for example, a deflection of a steering wheel. Based on the data about the set target steering angle of the vehicle, the control unit 130 can determine the target parameter.

[0027] Based on the obtained target parameter, the control unit 130 can control the vehicle. The vehicle can be controlled such that the vehicle is moved within a trajectory, which can be defined by the target parameter. To move the vehicle within this trajectory, the control unit 130 can determine a plurality of control parameters for the plurality of steering axles of the vehicle.

[0028] The data processing circuit 132 is configured to determine a first control parameter for the first steering axle. The first control parameter is determined based on the target parameter. For example, the first control parameter can be determined based on the overall steering angle of the vehicle and / or an axle-specific target steering angle of the first steering axle. The first steering axle can be a main steering axle of the vehicle. For example, the first steering axle can be a front axle of the vehicle.

[0029] The first control parameter is indicative of a parameter for controlling an electromechanical steering axle. For example, the first control parameter can be indicative of a deflection of the wheels of the first steering axle. The first control parameter can, for example, comprise a parameter for controlling an electric motor of an actuator of the first steering axle. The parameter for controlling the electric motor can generate a deflection of the wheels of the first steering axle by a desired steering angle.

[0030] The data processing circuit 132 is configured to determine a second control parameter for the second steering axle based on the target parameter. For example, the second control parameter can be determined based on the overall steering angle of the vehicle and / or an axle-specific target steering angle of the second steering axle. The second steering axle can be a secondary steering axle, i.e., not the main steering axle, of the vehicle. For example, the second steering axle can be a (second) front axle of the vehicle, a rear axle of the vehicle, or an axle of a trailer of the vehicle. The vehicle can include the trailer. In this case, the plurality of steering axles can be included by the vehicle and the trailer included by the vehicle.

[0031] The second control parameter is indicative of a parameter for controlling an electromechanical steering axle, a parameter for controlling a pneumatic steering axle, and / or a parameter for controlling an electrohydraulic steering axle. This means that the second steering axle can be either an electromechanical steering axle and / or an electrohydraulic steering axle. The second steering axle may not be an electromechanical steering axle.

[0032] For example, the second steering axle may comprise an electromechanical steering axle (first partial steering axle) and an electrohydraulic steering axle (second partial steering axle). In this case, the second control parameter may comprise two axle-specific control parameters. The first axle-specific control parameter may be for controlling the electromechanical steering axle (first partial steering axle), and the second axle-specific control parameter may be for controlling the electrohydraulic steering axle (second partial steering axle).

[0033] The data processing circuit 132 is configured to send the first control parameter for adjusting an orientation of the first steering axle. The first control parameter can be sent to an actuator, for example, a steering actuator, of the first steering axle. Optionally or alternatively, the first control parameter can be sent to a central control unit of the vehicle. The central control unit can then perform a control of the first steering axle or trigger a control of the first steering axle.

[0034] The data processing circuit 132 is configured to send the second control parameter for adjusting the orientation of the second steering axle. The second control parameter can be sent to an actuator, for example, a steering actuator, of the second steering axle. Optionally or alternatively, the second control parameter can be sent to a central control unit of the vehicle. The central control unit can then perform a control of the second steering axle or trigger a control of the second steering axle.

[0035] For example, an actuator of the respective steering axle can be controlled by the respective control parameter, or an action can be triggered. The alignment of the steering axle can therefore be adjusted by an actuator associated with the steering axle. The actuator can be controlled or triggered by the respective control parameter. Alternatively, the controlled or triggered actuator can also be external to the respective steering axle and communicatively connected to it.

[0036] The control unit 130 can control a multi-axle steering system for a vehicle comprising a plurality of steering axles with at least one electromechanical steering axle. For example, a multi-axle steering system that cooperates with an electromechanical steering system on the front axle can be controlled with the control unit 130. The inventors conceived that the processing of signals from different steering axles (for example, the first steering axle and the second steering axle), which presents a challenge, can be improved by the control unit 130. Furthermore, the control unit 130 can provide a steering architecture that takes into account an active steering axle of a trailer.The control unit 130 can therefore make it possible to combine an electro-hydraulic, an electromechanical and / or a pneumatic secondary steering axle, i.e. an additional steering system on an additional axle, with an electromechanical steering system on the main steering axle.

[0037] In particular, the control unit 130 can continuously determine possible trajectories of the vehicle. Based on the possible trajectories of the vehicle, the plurality of steering axles of the vehicle can be controlled.

[0038] For example, a steering architecture is proposed for a truck with multi-axle steering. This is a vehicle with two or more steering axles distributed across the entire vehicle combination. The additional steering axle(s) can therefore also be located in a trailer.

[0039] The target parameter or data for determining the target parameter can be received from a steering device as described above. For example, the steering device can include a steering wheel actuator, which can represent the connection to the driver. The steering wheel actuator can determine a driver's steering wheel deflection.

[0040] Optionally or alternatively, a desired steering wheel deflection can also be achieved via an input. For example, the vehicle can be controlled by a virtual driver. The virtual driver can include an option for inputting a steering angle specification and / or a trajectory of the vehicle, for example, by a user of the vehicle. The target parameter can then be determined based on the steering angle specification input and / or the trajectory of the vehicle. For example, a user can enter a steering angle specification and / or a trajectory using an input device, e.g., a touchscreen or a smartphone. Alternatively, the virtual driver can also determine a trajectory in the context of partially automated driving. The steering angle specification and / or the trajectory can then be sent from the input device to the control unit 130.The control unit 130 can thus receive the target parameter, for example, from an input device. The target parameter can thus include a target steering angle that is not determined by a steering wheel deflection, but rather by a user input and / or a determination of a trajectory by a virtual driver (e.g., an algorithm).

[0041] As described above, the control unit 130 determines the first control parameter and the second control parameter based on the target parameter. The first control parameter and the second control parameter can be determined using suitable means. For example, the first control parameter and the second control parameter can be determined using the Ackermann principle. This means that the steering axles, which are not mechanically connected to one another in reality, can be virtually connected according to the Ackermann principle in the basic function. Alternatively, other methods for determining the first control parameter and the second control parameter can be used, such as central steering, turning radius steering (the steering can be controlled according to a tire wear model. This means that during cornering, steering can be optimized for tire wear according to a defined model), or reverse steering.

[0042] The control unit 130 can receive axle data indicative of the first steering axle and the secondary (second) steering axle, i.e., the additional steering axle. This means that the control unit 130 can determine which steering axle, and at what distance, is steered on the vehicle or the optional trailer (included by the vehicle). Essentially, the control unit 130 can parameterize the geometry data of the vehicle (including the optional trailer) in the steering system. For example, the control unit 130 can read the axle data from a memory, for example, the optional memory 136. For example, the control unit 130 can read the axle data from the memory based on a look-up table. Optionally or alternatively, the control unit 130 can receive the axle data from a central control unit of the vehicle.

[0043] Based on the target parameter, the control unit 130 can periodically or permanently determine a possible trajectory (or a driving path) that is possible with the plurality of steering axles. Optionally, data about a possible trajectory can be received from a driver assistance system. This allows a limit to the maneuverability of the vehicle to be determined before a control intervention, i.e., before the first control parameter and / or the second control parameter are sent. This avoids sending control parameters that cannot be implemented to steer the vehicle in a possible trajectory (for example, limited by the vehicle's surroundings).

[0044] In addition to the geometry data, the axle data can also include the type of secondary steering. This means that the axle data can include information about whether the secondary steering axle is an electro-hydraulic, electromechanical, or pneumatic steering axle. Based on the type of secondary steering axle, the control unit 130 can switch one of several possible emergency functions in the event of a fault. For example, a secondary steering axle can be switched to power-free mode so that the secondary steering axle "runs along." For example, a secondary steering axle can be centered in the neutral position. This may require controlling an additional actuator of the secondary steering axle. For example, a request for steering brake interventions can be made from the braking system in order to steer the steering axles in the desired direction. For example, a request for braking interventions can be made to bring the vehicle to a standstill.

[0045] Furthermore, the control unit 130 can calculate the impact of a failure of various steering axles. This means that, depending on a speed, a load, and / or information about a steering axle, it can be determined which steering force is required at the remaining steering axles to ensure the steerability of the vehicle. The limit values ​​regarding steerability can be taken from the technical regulations and / or defined by the user. However, the limit values ​​can also result from the maximum possible actuating force that can be generated by the remaining actuators of the steering system, i.e., the usable steering axles of the plurality of steering axles.

[0046] The control unit 130 can optionally assume signal processing functions for the secondary steering axle. This means that the control unit 130 can not only specify the target steering angle, but also, for example, current / voltage curves, hydraulic flows, and / or pressures that implement the desired target steering angle. This means that the second control parameter can be a controlled variable such as a current / voltage curve, a hydraulic flow, and / or a pressure. Accordingly, a calculation of a controlled variable by a control unit of the secondary steering axles can be omitted. Accordingly, a control unit of the secondary steering axles can be simpler in design or even omitted, thereby saving costs and / or simplifying the design.

[0047] The second control parameter can be indicative of the orientation of the secondary steering axle. To align the secondary steering axle or the second steering axle, the control parameter can include control variables for controlling an actuator of the second steering axle. This allows control unit 130 to handle at least part of the signal processing of the second steering axle. Alternatively, control unit 130 can also handle all of the signal processing of the second steering axle. For example, this function can be implemented in a master and slave steering system. With dual programming, control unit 130 can control secondary steering axles among themselves.

[0048] For example, the vehicle could be a truck towing vehicle and a trailer. The towing vehicle can be coupled to the trailer via a wired connection, such as a towing vehicle-trailer link. Alternatively, the towing vehicle can be connected to the trailer via a wireless connection. Connecting the towing vehicle to the trailer can allow both to be steered during shunting operations.

[0049] In one embodiment, the control unit 130 can determine a turning circle parameter indicative of a turning circle of the vehicle. The turning circle parameter can be sent to inform a user. For example, the turning circle parameter can be sent to the input device from which a target steering angle can be received. Alternatively, the turning circle parameter can be sent to a central control unit of the vehicle. The turning circle parameter can serve to inform a user of the vehicle about a turning circle at a set target steering angle. For example, a user of the vehicle can enter a target steering angle using the input device. The target steering angle can be received by the control unit 130. Based on the target steering angle and the geometry and / or type of the plurality of steering axles, the control unit 130 can determine the turning circle parameter.The determined turning circle parameter can then be sent to the input device. The input device can then display the vehicle's turning circle for the entered target steering angle. This allows the user to correct or verify the target steering angle input.

[0050] In particular, the turning circle parameter can be determined for the failure of one of the multiple steering axles. The failure of one of the multiple steering axles can change, in particular increase, the turning circle of the vehicle. By determining the turning circle parameter, the user can be informed of the change in the vehicle's turning circle. This can improve the user experience.

[0051] In one embodiment, the first control parameter may be indicative of cascade control of the electromechanical steering axle and / or of torque control of an electric motor of an electromechanical steering axle. The first steering axle may not be an electrohydraulic steering axle. In particular, cascade control and / or torque control of an electric motor may be required to align the first steering axle because the first steering axle is an electromechanical steering axle.

[0052] With an electromechanical steering axle, electrical signals can act directly on the electric motor to control the steering movements. Cascade control can therefore be useful for an electromechanical steering axle to precisely control the speed and / or position of the motor and thus achieve precise steering movements.

[0053] In an electro-hydraulic steering axle, hydraulic forces are controlled by electrical signals. In this case, simple control of the valve positions and fluid flow may be sufficient to control the steering movements. Cascade control is not used for a single electro-hydraulic steering axle. Therefore, the first control parameter cannot include information required to adjust the hydraulic forces of a steering axle.

[0054] In general, with an electromechanical steering axle, the steering can be purely electromechanical. No hydraulic forces can be applied. The target steering angle, i.e., the control loop's reference variable, can be adjusted using torque control, speed control, and / or position control.

[0055] The speed of the electric motor can generate the steering movements of the steering axle and can be controlled to achieve the desired steering angle. Torque control of the electric motor can ensure that the torque of the electric motor is adjusted according to the steering movements and the vehicle's requirements. This is important for transferring the correct steering force to the wheels. Position control can be used to detect the actual position of the steering axle or steering wheel and compare it with the desired target steering angle. This control can ensure that the target steering angle is accurately achieved and that deviations are minimized.

[0056] In one embodiment, data processing circuit 132 may be configured to receive a mode parameter indicative of an operating mode of the vehicle. Data processing circuit 132 may be configured to determine the first control parameter and the second control parameter based on the mode parameter. The mode parameter may be received, for example, from an input device. For example, a user may select an operating mode using the input device.

[0057] Optionally or alternatively, the operating mode can be determined by the control unit 130. For example, the control unit 130 can determine an operating mode based on the target steering angle and possible trajectories of the vehicle. For example, the vehicle can be located next to a parking bay. Based on the target steering angle, the vehicle can determine the intention of the vehicle user to park the vehicle in the parking bay. Based on the user's intention, a suitable operating mode for parking the vehicle, for example, reverse steering, can be determined.

[0058] For example, a vehicle's operating mode can allow mechanical decoupling of the majority of steering axles. For example, a crab-like mode can be selected as the operating mode. This operating mode can be particularly useful in shunting operations. For example, a vehicle user can activate decoupling from the Ackermann principle via a switch in the cockpit or via input from a virtual driver, allowing additional driving functions, such as crab-like mode, to be implemented.

[0059] In one embodiment, the data processing circuit 132 can be configured to receive a braking parameter indicative of a status of a braking system of the vehicle. Furthermore, the data processing circuit 132 can be configured to determine the first control parameter and the second control parameter based on the braking parameter. For example, the braking parameter can be received from a central control unit of the vehicle. Alternatively, the braking parameter can be determined by the control unit 130. For example, the control unit 130 can control a braking device and determine data about a malfunction of the braking device. Based on the braking parameter, an additional braking effect can be achieved by aligning the plurality of steering axles. For example, an additional braking effect may be required due to the failure of a braking device.By receiving the braking parameter, the control unit 130 can determine the need for additional braking by the plurality of steering axles. This can improve the braking process of the vehicle.

[0060] For example, a function of the vehicle's braking system may be limited. Accordingly, additional braking by the plurality of steering axles may be required. Based on the braking parameter, a need for braking by the plurality of steering axles can be determined. As a result, a braking process of the vehicle can be improved by aligning the plurality of steering axles. The control unit 130 can therefore assume a braking function depending on the installed secondary steering axle. If a brake fails, the plurality of steering axles can be steered against each other to achieve an emergency braking function. For example, an emergency braking signal from a braking device may be necessary for emergency braking. The emergency braking signal can cancel the mechanical coupling in an emergency situation.

[0061] In one embodiment, the data processing circuit 132 can be configured to receive a driving assistance parameter indicative of a restriction on the maneuverability of the vehicle. Furthermore, the data processing circuit 132 can be configured to determine the first control parameter and the second control parameter based on the driving assistance parameter. Maneuverability of the vehicle can be restricted due to the vehicle's surroundings. For example, an obstacle in the vehicle's surroundings can restrict the vehicle's maneuverability. By receiving the driving assistance parameter, the control unit 130 can obtain information about possible inaccessible areas or trajectories in the vehicle's surroundings.

[0062] For example, the control unit 130 can receive the driver assistance parameter from a central control unit of the vehicle. Optionally or alternatively, the control unit 130 can receive sensor data from an environmental sensor of the vehicle. Based on the sensor data, the control unit 130 can determine the driver assistance parameter. By receiving the driver assistance parameter, a determination of the first control parameter and the second control parameter can be improved. In particular, a determination of a control parameter that could lead to a collision with an object in the vehicle's surroundings can be avoided. As a result, an intervention in the alignment of the plurality of steering axes can only occur if the determined first control parameter and the determined second control parameter correspond to a maneuverability of the vehicle.In one embodiment, the first control parameter can be used to adapt the orientation of the first steering axis to a first steering angle. The second control parameter can be used to adapt the orientation of the second steering axis to a second steering angle. The first steering angle can be different from the second steering angle. This allows for mechanical decoupling of the first steering axis from the second steering axis. This can improve vehicle control. For example, a crab-walk operating mode can be set for the vehicle.

[0063] As shown in Fig. 1a, the interface 134 may be coupled to the respective data processing circuitry 132 of the control unit 130. In examples, the control unit 130 may be implemented by one or more processing units, one or more processing devices, any means of processing, such as a processor, a computer, or a programmable hardware component operable with appropriately adapted software.

[0064] Likewise, the described functions of data processing circuitry 132 may also be implemented in software, which is then executed on one or more programmable hardware components. Such hardware components may be a general-purpose processor, a digital signal processor (DSP), a microcontroller, etc. Data processing circuitry 132 may be capable of controlling interface 134, so that any data transfer occurring via interface 134 and / or any interaction involving interface 134 may be controlled by data processing circuitry 132.

[0065] In one embodiment, the control unit 130 may include a memory 136 and at least one data processing circuit 132 operatively coupled to the memory and configured to perform the method described below.

[0066] In examples, interface 134 may correspond to any means for obtaining, receiving, transmitting, or providing analog or digital signals or information, e.g., any terminal, contact, pin, register, input terminal, output terminal, conductor, trace, etc., that enables the provision or receipt of a signal or information. Interface 134 may be wireless or wired and may be configured to communicate with other internal or external components, e.g., to send or receive signals or information.

[0067] As shown in Fig. 1b, the control unit 130 can be arranged in a steering actuator 140 of the vehicle 100. That is, the control unit 130 can be included in a steering axle 150. For example, the control unit 130 can be included in a main steering axle 150 of the vehicle 100. In this case, the control unit 130 can be communicatively connected to the secondary steering axle 152. The main steering axle can be included in the vehicle 100.

[0068] Alternatively, the control unit 130 can be arranged separately from the steering axles. For example, the control unit 130 can be included in the central control unit of the vehicle (see Fig. 2). In this case, the control unit 130 can be communicatively connected to the main steering axle 150 and the secondary steering axle 152. Alternatively, the control unit 130 can be separate from the steering axles and separate from a central control unit. In this case, the control unit 130 can also be referred to as a steering axle control unit.

[0069] In at least some embodiments, the vehicle 100 may, for example, correspond to a land vehicle, a road vehicle, a car, a bus, an off-road vehicle, a motor vehicle, or a truck. Optionally, the vehicle 100 may include a trailer. The control unit 130 may, for example, be part of a central control unit of the vehicle, a steering axle control unit superordinate to the steering axles, or a part of a steering axle, e.g., a steering actuator.

[0070] Fig. 2 shows a schematic view of a vehicle 200. The vehicle 200 includes a towing vehicle 210 and a trailer 220. The towing vehicle 210 includes a central control unit 230. The central control unit 230 (electronic control unit, ECU) may be a control unit as described with reference to Fig. 1. The central control unit 230 may also be referred to as central intelligence. The central control unit 230 may determine the control parameters for the plurality of steering axles 150, 152, 154, 156.

[0071] The central control unit 230 can receive a target parameter from a steering wheel device 270 comprising a handwheel actuator. Based on the target parameter, the target steering angles of the individual steering axles of the plurality of steering axles 150, 152, 154, 156 can be determined. The central control unit 230 can send the determined target steering angles to the respective steering axles of the plurality of steering axles 150, 152, 154, 156. The target steering angles can be independent of one another for each steering axle of the plurality of steering axles 150, 152, 154, 156 and / or independent of the type of actuators of the steering axles of the plurality of steering axles 150, 152, 154, 156.

[0072] The central control unit 230 can determine information about the vehicle configuration or receive data about it. For example, the central control unit 230 can determine which axle is a steering axle and / or which axle spacings are present. This information can be read from a look-up table, for example, as described above.

[0073] Depending on the vehicle's load condition and / or the driving situation, the central control unit 230 can determine a steering angle for each steering axle and send it to the respective steering axle. The steering angles can be determined according to the Ackermann principle or independently of the Ackermann principle.

[0074] The central control unit can be connected to an interface 274 for an assistance system or, if applicable, for a virtual driver. For example, information about the operating mode of the vehicle 200 selected by a user can be received via the interface 274.

[0075] A possible route can be sent to the assistance system via interface 274. The assistance system can then use the possible route for further calculations. A possible route can be received from the assistance system via interface 274. In the event of a failure scenario (e.g., a failure of a steering axle), the route can be adjusted accordingly by the central control unit 230, for example, reduced. For example, the central control unit 230 can control a stop or a maneuver in the event of a total failure. This allows the central control unit 230 to take over a task of the assistance system in a failure scenario. This can accelerate a response to a failure scenario.

[0076] The steering axle 250 is a primary steering axle of the vehicle 200. The primary steering axle 250 of the vehicle 200 is an electromechanical steering axle (electric power steering, EPS). The secondary steering axles 252, 254, 256 can be electromechanical steering axles and / or electrohydraulic steering axles (hydraulic power steering, HPS).

[0077] The individual steering axles 250, 252, 254, 256 can each comprise a control unit 260, 262, 264, 266. The control unit 260, 262, 264, 266 can receive the respective control parameter and control an orientation of the steering axle 250, 252, 254, 256. Alternatively, part of the control function can be assumed by the central control unit 230 (see the description with reference to Fig. 1).

[0078] Fig. 3 shows a block diagram of an embodiment of a method 300. The method 300 includes obtaining 310 a target parameter indicative of a target steering angle of the vehicle. The method 300 further includes determining 310, based on the target parameter, a first control parameter for the first steering axle. The first control parameter is indicative of a parameter for controlling an electromechanical steering axle. The method 300 further includes determining 320, based on the target parameter, a second control parameter for the second steering axle. The second control parameter is indicative of a parameter for controlling an electromechanical steering axle and / or a parameter for controlling an electrohydraulic steering axle.Furthermore, method 300 includes sending 340 the first control parameter for adjusting an orientation of the first steering axis and sending 350 the second control parameter for adjusting an orientation of the second steering axis. Method 300 can be performed by a control unit as described with reference to FIG. 1 and / or FIG. 2.

[0079] Further embodiments are computer programs for carrying out one of the methods described herein when the computer program runs on a computer, a processor, or a programmable hardware component. Depending on specific implementation requirements, embodiments of the invention can be implemented in hardware or in software. The implementation can be carried out using a digital storage medium, for example a floppy disk, a DVD, a Blu-ray disc, a CD, a ROM, a PROM, an EPROM, an EEPROM or a FLASH memory, a hard disk, or another magnetic or optical storage device on which electronically readable control signals are stored that can interact or interact with a programmable hardware component in such a way that the respective method is carried out.

[0080] Reference symbol (part of the description):

[0081] 100 vehicles

[0082] 130 Control unit

[0083] 132 Interface

[0084] 134 Data processing circuit

[0085] 136 memory

[0086] 140 steering actuator

[0087] 150 main steering axle

[0088] 152 secondary steering axle

[0089] 200 vehicles

[0090] 210 towing vehicle

[0091] 220 followers

[0092] 230 central control unit

[0093] 250 main steering axle

[0094] 252, 254, 256 secondary steering axle

[0095] 260, 262, 264, 266 control unit

[0096] 270 steering wheel device

[0097] 274 Interface

[0098] 300 procedures for one vehicle

[0099] 310 Obtaining a target parameter

[0100] 320 Determining a first control parameter

[0101] 330 Determining a second control parameter

[0102] 340 Sending the first control parameter

[0103] 350 Sending the second control parameter

Claims

Patent claims:

1. A control unit (130) for a vehicle, comprising: an interface (132) for communication with a first steering axle and a second steering axle; and a data processing circuit (134) configured to control the interface (132) and: obtain a target parameter indicative of a target steering angle of the vehicle; determine a first control parameter for the first steering axle based on the target parameter, the first control parameter indicative of a parameter for controlling an electromechanical steering axle; determine a second control parameter for the second steering axle based on the target parameter, the second control parameter indicative of at least one of a parameter for controlling an electromechanical steering axle, a parameter for controlling an electrohydraulic steering axle, and a parameter for controlling a pneumatic steering axle;send the first control parameter for adjusting an orientation of the first steering axis; and send the second control parameter for adjusting an orientation of the second steering axis.; 2. The control unit (130) according to claim 1, wherein the first control parameter is indicative of at least one of a cascade control of the electromechanical steering axle and a torque control of an electric motor of the electromechanical steering axle.

3. The control unit (130) according to any one of the preceding claims, wherein the data processing circuit (134) is configured to receive a mode parameter indicative of an operating mode of the vehicle; and to determine the first control parameter and the second control parameter based on the mode parameter.

4. The control unit (130) according to any one of the preceding claims, wherein the data processing circuit (134) is configured to obtain a braking parameter indicative of a status of a braking system of the vehicle; and to determine the first control parameter and the second control parameter based on the braking parameter.

5. The control unit (130) according to any one of the preceding claims, wherein the data processing circuit (134) is further configured to obtain a driving assistance parameter indicative of a limitation of maneuverability of the vehicle; and to determine the first control parameter and the second control parameter based on the driving assistance parameter.

6. The control unit (130) according to any one of the preceding claims, wherein the first control parameter is for adjusting an orientation of the first steering axis to a first steering angle; the second control parameter is for adjusting an orientation of the second steering axis to a second steering angle; wherein the first steering angle is different from the second steering angle.

7. A steering actuator (140) for a vehicle, comprising a control unit (130) according to one of the preceding claims.

8. A vehicle (100) comprising a control unit (130) according to any one of claims 1-6 or a steering actuator (140) according to claim 7.

9. A method (300) for a vehicle, comprising: Obtaining (310) a target parameter indicative of a target steering angle of the vehicle; Determining (320), based on the target parameter, a first control parameter for the first steering axle, the first control parameter being indicative of a parameter control of an electromechanical steering axle; Determining (330), based on the target parameter, a second control parameter for the second steering axle, the second control parameter being indicative of at least one of a parameter for controlling an electromechanical steering axle, a parameter for controlling an electrohydraulic steering axle, and a parameter for controlling a pneumatic steering axle; Sending (340) the first control parameter to adjust an orientation of the first steering axis; and Sending (350) the second control parameter to adjust an orientation of the second steering axis.

10. A computer program for carrying out the method (300) according to claim 9, when the computer program runs on a computer, a processor, or a programmable hardware component.

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