System and method for controlling electromechanical steering means of a vehicle

Abstract

System and method for controlling electromechanical steering of a vehicle The invention relates to a system for controlling an electromechanical steering means (2) for a vehicle, comprising a driving assistance system (3) configured for generating a first steering control information (L1) and a control unit (4) with at least one first feedback control unit (5), the control unit (4) having a first interface (S1) configured for receiving driver moment information (M) and at least one second interface (S2) configured for receiving adjustment information (A1, A2) depending on at least one of the driving state and / or driving situation, the control unit (4) being configured for providing a second steering control information (L2) depending on at least one of the driver moment information (M) and the adjustment information (A1, A2), and the system (1) is configured for providing to a steering system (2) of the vehicle a modified steering control information (L3) based on the first and second steering control information (L1, L2), on the basis of which a steering action of the electromechanical steering system (2) is performed.

Description

Technical Field

[0001] The present invention relates to a system and a method for controlling electromechanical steering means for a vehicle.

Background Art

[0002] Electromechanical steering means for a vehicle (also referred to as EPS: Electric Power Steering) are essentially known. Here, an electric actuator controlled by a program transmits a force to a steering mechanism to support and interfere with a driver's steering operation.

[0003] A lane-guided driver assistance system uses captured peripheral data to perform feedback control on a vehicle in the lateral and longitudinal directions along a planned trajectory. As an actuator for lateral vehicle control, an electromechanical steering means that receives an appropriate control signal from a control unit of a driver assistance system is often used.

[0004] As one of them, a system with a first interface variation configured to affect vehicle lateral dynamics by additively superimposing a moment value on the motor moment of a control motor of electromechanical steering means is known. Additionally, a system with a second interface variation configured to control vehicle lateral dynamics by providing a target steering angle is also known. In this case, the steering angle feedback control means is implemented in a control device of the electromechanical steering means.

[0005] A major design goal in a driver assistance system is high control quality in lane guidance. Pursuing high steering comfort at the same time when a driver performs overriding steering often causes target conflicts. Here, "overriding steering" is interpreted as a steering operation performed by a driver who holds a steering device different from the steering operation set by the driver assistance system.

[0006] In any interface variation, in known implementations, the magnitude, transition, and direction of the steering moment during override steering by the driver are not subdivided according to their effects for each driving situation, and since it is always in the opposite direction to the steering operation by the driver, there are drawbacks such that it is only marginally reasonable or is felt to be unnatural and unacceptable.

[0007] In these known implementations, for example, the moment that the driver has to apply to the steering device, hereinafter referred to as the driver moment, continuously increases up to a certain value corresponding to the height of the safety barrier that limits the motor moment of the servomotor of the electromechanical steering means to enable the driver to perform override steering reliably even with a slight override steering. The increase in this driver moment is due to the fact that the active operation by the driver acts not only as a disturbance moment directly on the angle feedback control system from the perspective of feedback control, but also because the changed vehicle orientation is interpreted as a disturbance value for the trajectory tracking feedback control system. These interferences by the driver are corrected as the dynamics of the overall disturbance transfer function of the lateral feedback control. The greater the dynamics of the overall disturbance transfer function, the faster the counter moment on the driver increases. Furthermore, the counter moment on the driver reaches a higher absolute value the higher the DC gain of the overall disturbance transfer function.

[0008] Among the above effects, in extreme cases, for example, during an emergency steering maneuver, the driver assistance system has a drawback that it interferes with the driver by making the driver apply a stronger steering moment in order to override the setting of the driver assistance system that aims at a different guiding target at that time without considering the driving situation.

[0009] Generally, the above effects reduce the driving comfort during cooperative driving, i.e., when the driver and the driving assistance system influence each other, and based on this, the trust in the driving assistance function also decreases.

Summary of the Invention

Problems to be Solved by the Invention

[0010] The problem of the present invention starting from this is to provide a system for controlling electromechanical steering means for a vehicle that can enable a more natural cooperative driving behavior that can be accepted as reasonable by the driver without significantly degrading the performance of the driving function.

Means for Solving the Problems

[0011] This problem is achieved by a system having the features described in independent claim 1. Preferred embodiments are the subject of the dependent claims. A method for controlling electromechanical steering means for a vehicle is the subject of parallel independent claim 15.

[0012] According to a first aspect, the present invention relates to a system for controlling electromechanical steering means for a vehicle. The vehicle includes a driving assist system configured to generate first steering control information. To this end, the system has a control unit with at least one first feedback control unit. The control unit includes a first interface configured to receive driver moment information. Therefore, the control unit includes a second interface configured to receive at least one piece of adjustment information depending on at least one driving state and / or driving situation. It is preferable that one piece of first and one piece of second adjustment information are provided via the second interface. At this time, at least one of the adjustment information depends on the driving state or driving situation. The control unit is configured to provide second steering control information depending on the driver moment information and at least one piece of adjustment information. Further, the system is also configured to provide the steering system of the vehicle with changed steering control information based on the first and second steering control information, based on which the steering operation of the electromechanical steering system is performed. Here, "the steering operation of the electromechanical steering system is performed based on the changed steering control information" means that the changed steering control information itself or a value derived therefrom, for example, a value obtained by the transfer function of the safety barrier, is used to initiate the steering operation of the electromechanical steering system.

[0013] The technical advantage of the system according to the present invention is that the driver can set the driver moment felt from the steering device according to the driving state or driving situation during cooperative driving, thereby obtaining a driving behavior that seems natural to the driver. It is preferable that overriding steering of the setting of the driving assist system is made difficult to tell the driver that it is better to follow the setting of the driving assist system from the driving situation only in extreme cases, for example, during an emergency steering maneuver.

[0014] According to an embodiment, the first steering control information is angle information, torque information for a servo motor of an electromechanical steering system, or information proportional to the torque of the servo motor of the electromechanical steering system. Using this, the driving assist system controls the electromechanical steering means with respect to set steering angle information or a default set moment, and these set steering angle information or default set moment are changed to changed steering control information by second steering control information according to driver involvement. Thereby, the system can be adopted in either an interface variation having an angle interface or an interface variation having a moment interface.

[0015] According to an embodiment, the first adjustment information is a driver moment threshold. The control unit is configured to be able to generate second driver moment information that contributes to the change of the first steering control information provided from the driving assist system when the absolute value of the driver moment information exceeds the driver moment threshold. Thereby, the setting of the driving assist system is changed by the driver who is overriding the steering only when the driver moment threshold is exceeded. That is, for example, an unintentional weak driver's steering operation does not affect the setting of the driving assist system.

[0016] According to an embodiment, the second adjustment information is overriding steering toughness information, which is a measure of the steering resistance that a driver must overcome in order to override-steer the steering device and overcome the steering behavior set by the driving assistance system. The overriding steering toughness information forms a body of information similar to the spring constant of a variable spring that can be set, for example, by the force that must be overcome to compress the spring. And the overriding steering toughness information determines how difficult it is for the driver to influence the steering behavior set by the driving assistance system. By changing the overriding steering toughness information, depending on the situation, it is possible to set the amount of driver torque in the steering device required to affect the steering operation of the predetermined electromechanical steering system.

[0017] According to an embodiment, the control unit is configured to be able to adjust the feedback control behavior of the first feedback control unit of the control unit based on the overriding steering toughness information. It is preferable that at least one gain factor of the first feedback control unit is adjusted according to the overriding steering toughness information. It is also possible to adopt a function that expresses the required degree of overriding steering toughness as at least one gain factor. At this time, it is preferable that an interdependent relationship is established in which high overriding steering toughness is implemented as a low feedback control loop gain and vice versa. Additionally, it is also preferable that the adjustment of at least one cut-off frequency of the first feedback control unit is implemented to meet the stability criteria. The adjustment of the cut-off frequency can be implemented, for example, according to the overriding steering toughness information. Here too, it is possible to adopt a function that expresses the required degree of overriding steering toughness as at least one cut-off frequency.

[0018] According to an embodiment, the control unit is configured to receive one first and one second adjustment information, and it is possible to set one of the two adjustment information to a fixed value and the other adjustment information to a value depending on the driving state or driving situation, or to set both the first and second adjustment information to values depending on the driving state or driving situation. Thereby, the steering behavior of the driving assist function can be made dependent on the driving state and driving situation so as to achieve as natural a cooperative driving behavior as possible.

[0019] According to an embodiment, the control unit is configured such that the first feedback control unit can receive a moment difference having an absolute value that is zero when the absolute value of the driver moment information is less than or equal to the driver moment threshold value, and has an absolute value reduced by the driver moment threshold value from when the driver moment information exceeds the driver moment threshold value. By doing so, it is possible to ensure that the setting of the steering assist system is affected only when the driver applies a significant moment to the steering device.

[0020] According to an embodiment, the first feedback control unit has an absolute value characteristic curve that monotonically decreases above the cut-off frequency. Such a feedback control behavior is advantageous for the cooperative driving behavior because it can effectively avoid the steering vibration as a result of the feedback control loop generated by, for example, the negative feedback of the driver moment.

[0021] According to an embodiment, the first feedback control unit has a feedback control behavior related to a PT1 controller. This type of controller is advantageous in the interactive control affected by the driver of the vehicle and the driving assist system.

[0022] According to an embodiment, the first feedback control unit has a feedback control behavior such that the moment difference supplied as an input value to the first feedback control unit is reduced by the change of the first steering control information based on the second steering control information. Thereby, the driving assist function is gradually adjusted to the driver's steering setting side, and thus, a system feedback control behavior is achieved in which the counter moment applied to the driver by the driving assist system also decreases.

[0023] According to an embodiment, for a case where the first steering control information is angle information, yaw rate information, or curvature value information, etc., a second feedback control unit is provided which is configured such that the set moment information of the steering angle feedback control means for the servo motor of the electromechanical steering system, or information proportional to the set moment information, can be used as the steering angle information, and the yaw rate information or the curvature value information can be used as the second steering control information. Thereby, the output information affected by the driver moment information can be converted by the second feedback control unit so that it can be used for directly changing the first steering control information, for example, by an arithmetic operation of addition or subtraction, with respect to the second steering control information provided from the system.

[0024] According to an embodiment, the second feedback control unit is configured to be able to receive the set moment information weighted by the activation factor of the steering angle feedback control means for the servo motor of the electromechanical steering system, and the activation factor is provided from the first feedback control unit. In addition, it is preferable that the feedback control loop of the second feedback control unit receives the moment information and performs an arithmetic operation with the set value. The moment information is provided, for example, from the steering angle feedback control means of the electromechanical steering system. For example, the moment information is subtracted from the set value, and the generated feedback control difference is multiplied by the activation factor. Subsequently, the result of this multiplication is input to the second feedback control unit as input information. The magnitude of the torque of the servo motor, when oversteered by the driver, is mainly the degree of the moment applied to the driver. The second feedback control unit attempts to reduce the feedback control difference multiplied by the activation factor, thereby effectively reducing the running assist function from opposing the driver. The degree of reduction is set by the magnitude of the activation factor.

[0025] According to an embodiment, the second feedback control unit is configured to receive the oversteering stiffness information and be able to adjust the feedback control behavior of the second feedback control unit based on the oversteering stiffness information. In addition, it is preferable that at least one gain factor of the second feedback control unit is adjusted according to the oversteering stiffness information. It is also possible to adopt a function that expresses the required degree of oversteering stiffness as at least one gain factor. At that time, it is preferable that the interdependent relationship in which high oversteering stiffness is implemented as a low feedback control loop gain and vice versa holds. Additionally, it is also preferable that the adjustment of at least one cut-off frequency of the second feedback control unit is performed to meet the stability criteria. The adjustment of the cut-off frequency can be performed, for example, according to the oversteering stiffness information. Here too, it is possible to adopt a function that expresses the required degree of oversteering stiffness as at least one cut-off frequency.

[0026] According to an embodiment, the second feedback control unit has an absolute value characteristic curve that monotonically decreases above the cut-off frequency and / or a feedback control behavior according to a PT1 controller. Such a feedback control behavior, or rather, this type of controller, is advantageous in an interactive control by the vehicle driver and the influence of the driving assistance system.

[0027] According to a further aspect, the present invention relates to a method for controlling electromechanical steering means for a vehicle, which includes a driving assistance system that provides first steering control information and a control unit having a first feedback control unit, provided that the driving unit receives driver moment information applied by a human driver to the steering and receives adjustment information depending on at least one driving state and / or driving situation, provided that the control unit provides second steering control information depending on the driver moment information and at least one adjustment information, and provided that the system provides, to the steering system of the vehicle, modified steering control information based on the first and second steering control information, based on which a steering operation of the electromechanical steering system is carried out.

[0028] Expressions such as "approximately", "substantially", or "substantially" in the present invention are interpreted as an error within + / - 10%, preferably within + / - 5% from the exact value, and / or an error that is not significant for the function.

[0029] The development forms, advantages, and application scopes of the present invention are shown by the following description of the embodiments and the drawings. At this time, all the described and / or illustrated features are, in each case, and in any combination, independent of each claim or the combination with its reference source, and are the subject of the present invention. In addition, the content of the claims is also a component of the specification.

[0030] Hereinafter, the present invention will be described in detail based on the drawings and embodiments. Description of the drawings:

Brief Description of the Drawings

[0031]

Figure 1

[0031] illustrates a schematic depiction of a first embodiment of a system for controlling electromechanical steering means for a vehicle, wherein the control of the electromechanical steering means is carried out by a driving assist system using moment information; and

Figure 2

Figure 1

[0032] FIG. 1 schematically shows, by way of example, a block diagram of a first embodiment of a system 1 used to control a steering system 2 having an electrodynamic drive system (EPS: electric power steering). In the case of such a steering system 2, a program-controlled electric servo motor supports the driver's steering operation or, in the case of autonomous driving or semi-autonomous driving, at least partially performs the steering operation itself.

[0033] The steering system 2 according to the first embodiment has a moment interface; in other words, the steering system 2 is configured to receive, as input information, torque information for the servo motor of the steering system 2 or information proportional to the torque, for example, information regarding the current flowing through the servo motor of the steering system 2.

[0034] System 1 has a driving assistance system 3 that provides first steering control information L1 to an output interface. The driving assistance system can have, for example, a surrounding recognition unit 3.1 that creates a surrounding model of the vehicle area using sensors. Furthermore, the driving assistance system 3 can also have a trajectory planning unit 3.2. The trajectory planning unit 3.2 is at least indirectly connected to the surrounding recognition unit 3.1, receives the information of the surrounding recognition unit 3.1, and is configured to be able to plan a driving trajectory based on this information.

[0035] In addition, it is preferable that the driving assistance system 3 also has a trajectory tracking feedback control 3.3. This is at least indirectly connected to the trajectory planning unit 3.2 and is configured to be able to calculate control information for the vehicle in order to move the vehicle on the calculated and selected driving trajectory. The output information of the trajectory tracking feedback control 3.3 is preferably the set steering angle φ 設定 for driving on the selected driving trajectory.

[0036] In addition, it is preferable that the driving assistance system 3 also has a steering angle feedback control means 3.4. The steering angle feedback control means 3.4 is at least indirectly connected to the trajectory tracking feedback control 3.3 and receives the control information of this trajectory tracking feedback control 3.3, particularly preferably the set steering angle. The steering angle feedback control means 3.4 is preferably configured to be able to provide, as a default setting value, torque information for the servo motor of the steering system 2 or information proportional to the torque, for example, information regarding the current flowing through the servo motor of the steering system 2. Also, the steering angle feedback control means 3.4 can be configured to reduce disturbing effects, such as vibrating steering behavior. The steering angle feedback control means 3.4 preferably provides the first steering control information L1.

[0037] In addition, some of the units 3.1 to 3.4 of the above driving assistance system 3 can be connected to a unit 7 that provides driving state recognition or driving situation recognition, as suggested by the vertical arrows in FIG. 1. The unit 7 can be, for example, a functional component of the driving assistance system 3, i.e., provided within the control unit of the driving assistance system 3. However, it is also possible to be provided within a control unit independent of the driving assistance system 3. In addition, the unit 7 can also have driver observation means for capturing and processing the driver's behavior, line-of-sight direction, and / or actions in order to estimate the driving commands the driver will issue in the future.

[0038] Furthermore, the system 1 also has a control unit 4 configured to be able to provide second steering control information L2. Here, the system 1 uses the second steering control information L2 to generate third modified steering control information L3 by using the first steering control information L1, so that even when the driving assistance function acting on the lateral control of the vehicle is in operation, the driving behavior can be reduced according to the driving state and / or driving situation so as to give the impression that it is not forced on others, and a greater degree of freedom for the human driver to participate in the driving of the vehicle can be given according to the driving state and / or driving situation, and the driving is changed so as to obtain improved cooperative driving.

[0039] The control unit 4 includes a first interface S1 configured to be able to receive driver moment information M. Here, the driver moment information M is a value that is proportional to torque information or this torque information and indicates the degree to which the driver's torque is applied to the steering device of the vehicle.

[0040] In addition, the driver moment information M is preferably made an absolute value using an absolute value unit 4.1 first. The output of the absolute value unit 4.1 is provided with driver moment information |M| that is independent of the sign regardless of the driver's steering direction.

[0041] It should be noted that in the illustrated embodiment, a counting arrow system is adopted in which a positive driver moment has the same effect as the positive motor moment of the electromechanical steering system 2, or the positive steering angle for normal left curve driving. In addition, the control unit 4 also has a second interface S2 in which one first and one second adjustment information A1, A2 are provided. Preferably, the first and second adjustment information A1, A2 are provided from the unit 7. At least one of the first and second adjustment information A1, A2 is a value corresponding to the driving state and / or the driving situation, that is, the first and / or second adjustment information A1, A2 is changed depending on the driving state and / or the driving situation recognized by the unit 7. The first and second adjustment information A1, A2 are adjusted according to the driving state and / or the driving situation.

[0042] The first adjustment information A1 is preferably a driver moment threshold value, that is, a threshold value for torque information or a value proportional to the torque information. The first adjustment information A1 is used in the control unit 4 to determine a threshold at which the driver can intervene in the steering behavior set by the driving assist system 3 when the value is exceeded. For this, the absolute value unit 4.1 provides the driver moment information |M| independent of the sign, and the first adjustment information A1 is supplied to the subtraction point 4.2 that provides the moment difference information DM on its output side.

[0043] The moment difference information DM is supplied as input information to the first feedback control unit 5. It also receives, as additional input information, the second adjustment information A2. The feedback control unit 5 acts as a limit controller, that is, by adjusting the feedback control behavior of the first feedback control unit 5 using the second adjustment information A2, it determines the strength with which the driver can override the steering behavior set by the driving assist system. In other words, when the driver has to apply more force to the steering than what is required, the driving assist system starts to gradually yield to the driver's desired deviation direction by applying torque. The degree of this yielding is defined by the adjustment information. Put more simply, this variably sets the strength of the steering resistance felt when overriding the steering setting of the driving assist system. Therefore, the second adjustment information A2 is hereinafter also referred to as "override steering toughness".

[0044] Based on the second adjustment information A2, the feedback control behavior of the first feedback control unit 5 is changed. In particular, the second adjustment information A2 affects the feedback control gain within the first feedback control unit 5. At that time, one or more gain factors of the first feedback control unit 5 are affected so as to obtain the desired override steering toughness.

[0045] For example, there is an interdependent relationship between the second adjustment information A2 and the feedback control loop gain within the first feedback control unit 5, that is, a larger second adjustment information A2, or override steering toughness, is due to a smaller feedback control gain, and vice versa. In other words, a required weaker override steering toughness can be represented by a higher feedback control gain of the first feedback control unit 5, and vice versa. In the first extreme event where the second adjustment information A2 is at its maximum, or the override steering toughness is at its maximum, the feedback control loop gain becomes zero, that is, thereby the control unit 4 is, so to speak, stopped, and the override steering toughness is determined only by, or substantially only by, the disturbance reduction characteristics of the steering angle feedback control means 3.4.

[0046] In the first extreme event where the second adjustment information A2 is minimum or the override steering toughness is minimum, the feedback control gain becomes a large value. This value is limited only by, for example, the investment made to design and implement the stabilization measures.

[0047] When the override steering toughness is low, the assist system will yield during cooperative driving and will be felt by the driver as not being coercive. In particular, when the set override steering toughness is low, depending on the height of the loop gain, it may be necessary to adjust the cut-off frequency of the first feedback control unit 5 in order to meet the stability criteria. The adjustment of the (possibly multiple) filter cut-off frequencies of the first feedback control unit 5 is also preferably carried out based on the second adjustment information A2.

[0048] In addition, the control unit 4, particularly the first feedback control unit 5, has a saturation function. The saturation function is selected such that, for example, the maximum value of the output information of the first feedback control unit 5 or the maximum value of the second steering control information L2 is limited.

[0049] As a result, the absolute value of the output information of the first feedback control unit 5 is limited within a threshold value that can be determined in advance by a saturation function. The definition of this threshold value also provides an additional degree of freedom in designing the override steering behavior. This threshold can capture a defined constant value, or it can be designed to depend on the driving situation as well. By lowering the threshold, the counter moment on the driver can be set to increase again when the override steering reaches a certain level. The reason is that when the threshold is relatively low, when the first steering control information L1 reaches a specific level of override steering, it exceeds the second steering control information L2 in the absolute value comparison. As a result, the steering control information L3 formed and changed by the total point 8 strengthens the requirement of the driving assistance system to correct and control the driver as an external disturbance in the feedback control loop. Thereby, the counter moment on the driver increases again. As one application, when the desired deviation from the setting of the driving assistance system is small, the driver moment is relatively small at first, but it increases after the desired deviation becomes large. Thus, an example can be given where the allowable zone for override steering is transmitted tactually to the driver.

[0050] A high limit threshold for the second steering control information L2 leads to the first steering control information L1 being overwritten. Therefore, the changed steering control information L3 increasingly represents the driver's desire for override steering, and the feedback control target of the driving assistance system is gradually eliminated. As a result, the steering moment required for the steering maneuver becomes smaller than that required without the driving assistance function. As one application, for example, an emergency avoidance steering maneuver can be cited, where this method not only reduces the counter moment on the driver but also supports it.

[0051] Subsequently, the output information provided by the first feedback control unit 5 is multiplied by the sign of the driver moment, as indicated by the block "sign" in FIG. 1. The "sign" function determines the sign of the driver moment information M and multiplies it by the output information of the first feedback control unit 5, so that the sign of the driver moment information M is reflected in the second driver moment information L2. As a result, the control unit 4 can provide the steering control information L2 adjusted in the direction of reducing the driver moment without depending on the steering device.

[0052] The second steering control information L2 is transmitted to the addition point 8. There, the second steering control information L2 and the first steering control information L1 are added to provide the third steering control information L3. Of course, if the counting arrow system of the addition point 8 is reversed, it can be replaced by a subtraction point, and as a result, it goes without saying that a functionally identical system can be obtained.

[0053] The third steering control information L3 is supplied to a safety barrier SB that provides the fourth steering control information L4 on its output side. The safety barrier SB is a unit that monitors and actively limits the control amount from a physical consideration regarding the absolute value and slope.

[0054] The safety barrier SB is configured, for example, to monitor the changed steering control information L3 from the perspective of strict compliance with safety goals and change it if necessary when the safety goals cannot be met. By doing so, for example, the absolute value and slope of the changed steering control information L3 can be monitored and actively limited if necessary.

[0055] The fourth steering control information L4 generates the input value of the electromechanical steering system 2. Depending on the driver moment information M, the first and second adjustment information A1, A2, the first feedback control unit 5 changes the steering control information L1 generated by the driving assist system 3, and generates second steering control information L2 to give the driver's influence depending on the first and second adjustment information A1, A2 to the steering system 2 of the vehicle.

[0056] As suggested by the arrows connecting from the driving assist system 3 and the steering system 2 to the upper unit 7, the information of the functional units 3.1 to 3.4 of the driving assist system 3 and the electromechanical steering means 2 is used to capture the driving state or driving situation.

[0057] FIG. 2 shows, by way of example and schematically, a block diagram of a second embodiment of the system 1 used to control a steering system 2 having an electrodynamic drive system. The steering system 2 according to the second embodiment has an angle interface, that is, the steering system 2 is configured to receive, as input information, angle information, in particular, set steering angle information φ 設定 It is preferably built into the steering system 2. The driving assist system 3 provides the set steering angle information φ 設定 to the output interface as the first steering control information L1.

[0058] Also, the driving assist system also has a surrounding recognition unit 3.1 that creates a surrounding model of the vehicle area using, for example, sensors. Further, the driving assist system 3 may have a trajectory planning unit 3.2. The trajectory planning unit 3.2 is at least indirectly connected to the surrounding recognition unit 3.1, receives the information of the surrounding recognition unit 3.1, and is configured to plan a driving trajectory based on this.

[0059] In addition, it is preferable that the driving assist system 3 also has a trajectory tracking feedback control 3.3. This is at least indirectly connected to the trajectory planning unit 3.2 and is configured to be able to calculate control information for the vehicle in order to move the vehicle on the calculated and selected driving trajectory. The output information of the trajectory tracking feedback control 3.3 is, in the illustrated embodiment, the first steering control information L1 in the form of the set steering angle information φ 設定 that can travel on the driving trajectory selected based on it.

[0060] In addition, some of the units 3.1 to 3.3 of the driving assist system 3 described above can be connected to a unit 7 that provides driving state recognition or driving situation recognition, as suggested by the vertical arrows in FIG. 2. The unit 7 can be, for example, a functional component of the driving assist system 3, that is, provided in the control unit of the driving assist system 3. However, it can also be provided in a control unit independent of the driving assist system 3. In addition, the unit 7 can also have driver observation means for capturing and processing the driver's behavior, line of sight direction, and / or actions in order to estimate the driving commands that the driver will issue in the future.

[0061] Here too, the system 1 also has a control unit 4 configured to be able to provide second steering control information L2. Here, the system 1 uses the second steering control information L2 to use the first steering control information L1 to generate the changed steering control information L3 by this change, so that even when the driving assist function that acts on the lateral control of the vehicle is in operation, the driving behavior is forced on others. According to the driving state and / or according to the driving situation, the impression is reduced, and a greater degree of freedom for the human driver to participate in the driving of the vehicle is given according to the driving state and / or according to the driving situation, and the driving state is changed so that improved cooperative driving can be obtained.

[0062] The interfaces S1 and S2 of the control unit 4, the processing of the information received at the interfaces S1 and S2 by the absolute value unit 4.1, and the first feedback control unit 5 are the same as those in the first embodiment according to FIG. 1. For the above description, please refer to it. These are also valid in the embodiment of FIG. 2.

[0063] The substantial difference from the embodiment according to FIG. 1 is that in the embodiment according to FIG. 2, the second steering control information L2 is not directly provided by the first feedback control unit 5, but the first feedback control unit 5 provides the activation factor AF.

[0064] Furthermore, the control unit 4 has a subtraction point 4.2. In the shown embodiment, the set value is "0" at first, but the set value and the torque information DI of the electromechanical steering system 2 are supplied. The torque information DI corresponds to, for example, the operating moment of the steering angle feedback control means of the required electromechanical steering system 2, but is also directly proportional to the current requested by the servo motor. For this, it is also possible to use the total torque derived from the resulting measured motor current after subtracting the moment demand or current demand from other functions of the operating unit of the electromechanical steering system 2.

[0065] At the subtraction point 4.2, the torque information DI is subtracted from the set value. The result of this difference is changed based on the activation factor AF. In particular, the output information of the subtraction point 4.2 is multiplied by the activation factor AF, and the multiplication result is supplied to the second feedback control unit 6 as input information. The activation factor is preferably a rational number between 0 and 1 (AF ∈ [0,1]). The activation factor is affected by the driver moment information M and the first and second adjustment information A1, A2. The value of "0" means that the driver perceives hard steering, that is, cooperative driving is very suppressed. Conversely, the value of "1" means that the steering system 2 tolerates the driver's cooperation at a high level, and the steering requirements of the driver assistance system 3 are less weighted.

[0066] The second feedback control unit 6 receives the difference weighted by the activation factor AF. The second feedback control unit 6 is configured as, for example, a moment feedback control loop. Incidentally, the second feedback control unit 6 is preferably configured as a PT1 controller.

[0067] In a preferred embodiment, the connection between the second feedback control unit 6 and the first feedback control unit 5 is such that the first feedback control unit 5 has a value between 0 and 1 at its output interface, whereby the feedback control difference by which the second feedback control unit 6 is scaled generates the activation factor AF. Without driver interaction, the first feedback control unit generates an activation factor of value 0, whereby the torque information of the steering system 2, particularly the steering angle feedback control means of the steering system 2, is not fed back. In the case of driver interaction, the first feedback control unit 5 generates an activation factor AF having a value greater than 0 depending on the first and second adjustment information A1, A2. It is preferable that the contribution of the second adjustment information A2 (i.e., override steering stiffness) to the activation factor AF acts such that a higher second adjustment information A2, i.e., a stronger override steering stiffness, results in a smaller activation factor AF at the output interface of the first feedback control unit 5.

[0068] The contribution of the difference between the driver moment information M and the first adjustment information A1 (i.e., driver moment threshold) to the activation factor AF is preferably such that the activation factor AF increases as the driver moment information M exceeds the first adjustment information A1 by a greater amount, i.e., the activation factor AF increases as the driver moment residue increases.

[0069] Incidentally, the contribution borne by the adjustment information to obtain the desired result is preferably weighted, particularly with minimum operation applied.

[0070] At that time, the weighting factors k1 and k2 that give degrees of freedom in the design of the first feedback control unit are used. Incidentally, the second adjustment information A2 preferably takes a value within the range of 0 and 1.

[0071] From the assignment expressed as follows, DM = min(1, max(0, (|M| - A1))) In the formula, DM is the moment difference (as the input information of the first feedback control unit 5), |M| is the absolute value of the driver moment information, and A1 is the first adjustment information (driver moment threshold value). The impulse response g(t) of the first feedback control unit 5 is convolved with the moment difference DM (convolution operator *). The following relationship is obtained for the adjustment factor AF: AF(t) = min(1, max(0, (min(k1·(DM(t) * g(t)), k2·(1 - A2(t)))))) As shown in FIG. 2, the second adjustment information A2 can be used to affect the feedback control behavior of the second feedback control unit 6. For example, the second adjustment information A2 can be used to increase the feedback control gain of the second feedback control unit 6 when the second adjustment information A2 is reduced. Depending on the degree of stability reserve force, it may also be advantageous to adapt the parameters of the second feedback control unit 6 that determine the frequency response, for example, by shifting the pole location (pole) and / or zero location (zero).

[0072] Also in the embodiment according to FIG. 2, the adaptation of the driver interaction depending on the driving situation at that time can be implemented only by the first adjustment information A1, only by the second adjustment information A2, or by a combination of both adjustment information A1 and A2. When only one of the two adjustment information A1 and A2 is dynamically changed depending on the driving state or driving situation, a fixed value is given to the other adjustment information. Incidentally, this value is preferably selected so as to result in the activation factor AF = 1 even when viewed individually, that is, to allow the most dynamic driver intervention.

[0073] The second steering control information L2 provided by the second feedback control unit 6 is transmitted to the addition point 9. There, the second steering control information L2 and the first steering control information L1 are added, and the changed steering control information L3 is provided thereby.

[0074] In addition, it is preferable that the third steering control information L3 is also supplied to a safety barrier SB that provides fourth steering control information L4 on its output side. The safety barrier SB is a unit that monitors the control amount in view of physical considerations with respect to the absolute value and the slope, and actively limits it.

[0075] The safety barrier SB is configured, for example, to monitor the changed steering control information L3 from the viewpoint of strictly adhering to safety goals, and to change it if necessary when the safety goals cannot be satisfied. By doing so, for example, the absolute value and the slope of the changed steering control information L3 can be monitored and actively limited if necessary.

[0076] The fourth steering control information L4 generates an input value for the electromechanical steering system 2. Depending on the driver moment information M, the first and second adjustment information A1, A2, the second feedback control unit 6 changes the steering control information L1 generated by the driving assist system 3, and the steering system 2 of the vehicle can be affected by the dynamic influence of the driver depending on the first and second adjustment information A1, A2. The second steering control information L2 is generated.

[0077] The control unit 4 receives, for example, a set value of the torque information DI of the angle controller of the electromechanical steering system 2, and depending on the magnitude of the moment difference ΔM and the second adjustment information A2, the moment difference ΔM acts to be reduced with the help of the second feedback control unit 6. At this time, the second feedback control unit 6 generates second steering control information L2 (steering angle bias signal) that is added to the first steering control information L1 provided from the trajectory tracking feedback control 3.3. Thereby, a feedback control loop is formed in which the moment difference ΔM is gradually reduced.

[0078] As suggested by the arrow pointing upward from the steering system 2 to the unit 7, the information of the electromechanical steering means 2 can also be used to capture the driving state or driving situation.

[0079] As described above, the unit 7 is configured to recognize and evaluate the driving situation or driving state. The unit 7 can also perform the observation of the driver, for example, using a camera, and based on this, it is also possible to determine the driver behavior. In particular, the unit can provide information on whether the driver's steering is in the same direction as the setting of the driver assistance system, or whether the driver is steering in the opposite direction to the setting of the driver assistance system.

[0080] The unit 7 can react to the driving situation, driving state, and driver behavior, for example, as follows: - When the driver steers into a dangerous area, the counter moment of the driving assistance system 3 can be significantly recognized, and the absolute values of the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness) should be higher when facing the direction of the safe driving lane. - When the driver is steering in the direction of the safe driving lane, it is better that the driver is not hindered from performing this maneuver. The absolute values of the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness) should be lower. - If the driver indicates a request for cooperation to the driving assistance system 3, for example, by hand moment, it should be made possible with less steering effort, i.e., at a lower intensity. Examples include that the driver wants to select a route passing on the right instead of the left of an obstacle, or that the driver wants a certain offset in the lateral direction instead of guiding exactly in the center of the lane, and the driver can convey such a desire to the driving assistance system 3 by appropriately turning the steering wheel. In these cases, the absolute values of the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness) take lower values. - When the driving assistance system 3 reaches the limit of the electromechanical steering system during cornering and the driver wants to support lateral guidance to avoid the vehicle deviating from the curve, this should be felt by the driver as support steering rather than counter-steering as a result of a high counter-moment in steering. In the case of such support steering, the driver only needs to apply a part of the steering force remaining after subtracting the maximum steering force depending on the limit of the electromechanical steering system. The absolute values of the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness) take higher values so that the control unit 4 transmits the first steering control information L1 unchanged, i.e., without being changed or substantially unchanged (i.e., the second steering control information is zero or very small) via the safety barrier SB to the electromechanical steering system 2. - When the driver performs an avoidance / emergency steering maneuver that has not yet been triggered by the emergency steering assistant function (or is not included in the scope of the assistant function) (for example, indicated by a high steering angular velocity), the steering moment directed from the steering angle feedback control means of the electromechanical steering means to the driver should be made very small so as not to interfere with the driver's avoidance maneuver. In this case, the absolute values of the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness) take lower values. If the driver performs an avoidance or emergency steering maneuver that has not yet been triggered by the emergency steering assistant function (or is not within the scope of the assistant function) (e.g., as indicated by a high steering angular velocity), the driver can obtain active steering support by the feedback control unit 5 without imposing restrictions or by imposing restrictions only after the output signal increases. - During the operation of the emergency steering assistant function (i.e., when the avoidance or emergency steering maneuver is performed by the driving assistance system), as long as the driver's steering is weak compared to the setting of the optimal avoidance trajectory, large absolute values are given to the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness). The optimal avoidance trajectory is a trajectory with the characteristic that the vehicle can pass by the obstacle with a safety distance without imposing a high load on the power transmission potential of the tires and without the vehicle becoming unstable. - During the operation of the emergency steering assistant function, if the driver's steering is more dynamic compared to the setting of the critical avoidance trajectory, large absolute values are given to the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness). The critical avoidance trajectory is a trajectory on which the vehicle has a large distance from the obstacle, but at the same time, there is a high probability of losing power transmission and becoming unstable. - During the operation of the emergency steering assistant function, if the driver selects a trajectory between the optimal avoidance trajectory and the critical avoidance trajectory by the steering maneuver, small absolute values are given to the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness). At this time, the optimal avoidance trajectory and the critical avoidance trajectory are newly calculated sequentially, and the re-evaluation of the driver reaction is performed respectively. - Especially in the case of lane transition at a construction site, the probability that the driver needs to correct the running track by intervention increases due to, for example, the low quality of the road markings present at the site. To ensure that the driver can make corrections with low steering costs, when the lane width is narrow or a construction site is recognized, small absolute values are given to the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness). - When the quality of the road markings is low, generally, the probability that the driver needs to correct the running lane during driving by intervention increases. Also in this case, to ensure that the driver can make corrections with as little steering cost as possible, similarly, small absolute values are given to the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness). - When the vehicle deviates from the running lane due to the driver's carelessness, the assistant system first intervenes and then starts to guide the vehicle into a safe lane area. However, when the driver takes full control, as long as it is predicted that the vehicle will not become unstable on the track selected by the driver as a premise, at any point in time, it is better not to go in the opposite direction of the driver's steering request. Under this condition, the absolute values of the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness) are set to small values. - When the driver selects a sporty driving mode (if this option is included in the vehicle equipment), the steering should provide stronger feedback. Also, accordingly, the command moment when the driver counter-steers should be increased. The absolute values of the first adjustment information A1 (driver moment threshold) and the second adjustment information A2 (override steering stiffness) are set to higher values.

[0081] In addition, the first adjustment information A1 (driver moment threshold) preferably depends on the internal feedback control error value of the lateral feedback control, and is set, for example, as follows: - The first adjustment information A1 is set higher as the lateral distance of the vehicle from the set trajectory is greater. - The first adjustment information A1 is set higher as the difference between the measured steering wheel angle and the set steering wheel angle is greater. - The first adjustment information A1 is set higher as the difference between the measured yaw rate and the set yaw rate is greater. In addition, the second adjustment information A2 (override steering stiffness) preferably also depends on the internal feedback control error value of the lateral feedback control, and is set, for example, as follows: - The second adjustment information A2 is set higher as the lateral distance of the vehicle from the set trajectory is greater. - The second adjustment information A2 is set higher as the difference between the measured steering wheel angle and the set steering wheel angle is greater. - The second adjustment information A2 is set higher as the difference between the measured yaw rate and the set yaw rate is greater. In addition, as the first and second adjustment information A1 and A2, when the driver steers against the settings of the driver assistance system and selects an alternative route that does not lead to a decrease in driving safety, it is preferable to select a small value.

[0082] In the opposite case, that is, when the driver has the same vehicle control target as that of the driver assistance system, or when the driver's alternative route may lead to, or is likely to lead to, a decrease in driving safety, it is preferable to select a large value as the first and second adjustment information A1 and A2. At this time, the driving safety can be evaluated by an expert system based on the predicted collision probability and the predicted loss of tire power transmission potential.

[0083] The control unit 4 and the unit 7 can also be implemented, for example, on the control device of the driving assistance system 3. As an alternative, the control unit 4 can be implemented on the control device of the electromechanical steering system 2. For this purpose, for example, the interface between the control device of the driving assistance system 3 and the control device of the electromechanical steering system 2 is extended for the transmission of the first and second adjustment information A1, A2.

[0084] In addition, it is advantageous for the system 1 to have one or more of the following functions: If switching between discontinuous values for the first and second adjustment information A1, A2 is assumed, these values are smoothed / interpolated as necessary before being executed by the control unit 4 to avoid unwanted jerky movements of the steering. Incidentally, the first and second adjustment information A1, A2 preferably has a continuous character and is determined, for example, by fuzzy logic calculation.

[0085] For example, in a construction site area where a low first adjustment information A1 should in principle be selected, when conflicting requirements of influence rules such as the activation of the emergency avoidance assistant and a high value for the first adjustment information A1 are demanded for the driver moment value, in the driving state recognition, it can be resolved, for example, by an arbitration unit.

[0086] The influence on the driver moment can be removed, for example, by appropriately replanning the set trajectory according to the driver's steering activity instead of implementing the above-mentioned limit feedback control by the control unit 4. For example, the planning of a trajectory exactly along the driving lane selected by the driver can be obtained by ignoring the feedback control means / initial state and setting the counter moment for the driver to 0 Nm.

[0087] The planning of the trajectory on the right or left side of the currently traveling trajectory is accompanied by a steering recommendation to the right or left.

[0088] The disadvantage of such a procedure is that during the implementation of the replanning, the feedback control means initial state (for example, the I component of the steering angle feedback control means) must be systematically reduced, that is, it cannot be completed only by measures at the planning level. In addition, in this approach, the cost for achieving seamless transition and the continuous steering moment transition required therefor is high.

[0089] The new trajectory due to the driver's steering in the direction of reducing the driver's steering moment is implicitly a component of the feedback control loop. In particular, considering the generally long potential response time between the triggered replanning and the influence of the driver moment, additional preventive measures for ensuring stability are required on the trajectory planning side. In the case of an emergency steering maneuver where the driver must not be disturbed, the trajectory must be newly planned every scanning step (for example, 10 ms) based on the currently active vehicle behavior by the driver. This involves high computational costs, but nevertheless, the angular feedback control component with damping characteristics cannot be eliminated. On the other hand, if the values of the first to second adjustment information A1, A2 are selected as "0", it can be achieved that the inhibitory contribution by the angular feedback control is zero at the moment interface to the electromechanical steering system 2. At the moment interface to the electromechanical steering system 2, the inhibition by the angular feedback control means can be substantially reduced by both adjustment information A1, A2 having values of zero except for a slight residual moment. Only by the interaction between the driver moment limitation and the trajectory replanning can an adjusted overall behavior be achieved.

[0090] The second adjustment information A2 (override steering stiffness) can also inherently influence the first adjustment information A1 (driver moment threshold) by controlling it according to the steering operation. The cost for ensuring stability and the like is also high in this case.

[0091] The above method is applicable even when it is implemented by yaw rate setting or curvature value setting instead of steering angle setting for the steering system 2. And this control unit 4 generates a correction value for the set yaw rate or the set curvature value instead of the steering angle bias.

[0092] Based on the angle interface to the electromechanical steering system 2, the driving assist system 2 additionally uses the actually measured steering wheel angle in the first control unit 4 in order to more dynamically configure the limitation of the driver moment during override steering. For this purpose, in an intermediate step, when the driver moment exceeds the first adjustment information A1, the set steering angle is proportionally mixed with the actually measured steering angle until the set steering angle finally coincides with the actually measured steering angle in the case where the driver moment information M is increasing. As a result, the feedback control difference of the steering angle feedback control means of the electromechanical steering system 2 becomes zero, and the moment demand for the servo motor of the steering system 2 also does not increase any further for the time being. However, in order to eliminate the feedback control means integration part in the steering angle feedback control means of the electromechanical steering system 2, further negative feedback of the moment information by the second feedback control unit is required.

[0093] The running assist system 2 based on the angle interface to the electromechanical steering system 2 can, in the control unit 4, instead of feeding back all the set moment information of the steering angle feedback control means, in the fixed value feedback control, consider the set moment information of the steering angle feedback control means after subtracting a defined ratio. However, this ratio is defined based on the first and second adjustment information A1, A2. When the second adjustment information (override steering stiffness) is high, or when the driver moment information M is still small, this ratio is selected to be high. When the driver moment information M increases, or when less adjustment information A2 (override steering stiffness) is required, this ratio is selected to be a small value with the final value being 0. This procedure has the possibility of requiring a steering system 2 with high dynamics in the implementation of the steering angle feedback control means, because otherwise, the reduction until the steering angle set value moment that acts against the driver becomes zero is too fast, and the second adjustment information A2 (override steering stiffness) may be felt to be too small. The subtraction of the ratio of the steering angle set value moment can alternatively be converted into the corresponding set value of the second feedback control unit.

[0094] The present invention has been described by the above embodiments. However, it goes without saying that numerous changes and variations are possible without departing from the scope of the claims defined in the claims. Note that the present invention may also include the following aspects: 1. A system for controlling an electromechanical steering means (2) for a vehicle, comprising a driving assist system (3) configured to generate one piece of first steering control information (L1), and a control unit (4) having at least one first feedback control unit (5), wherein the control unit (4) has a first interface (S1) configured to receive driver moment information (M), and at least one second interface (S2) configured to receive adjustment information (A1, A2) depending on at least one of a driving state and / or a driving situation, the control unit (4) is configured to provide second steering control information (L2) depending on at least one of the driver moment information (M) and the adjustment information (A1, A2), and the system (1) is configured to provide the steering system (2) of the vehicle with one piece of modified steering control information (L3) based on the first and second steering control information (L1, L2), based on which the steering operation of the electromechanical steering system (2) is performed, system. 2. The system according to 1. above, characterized in that the first steering control information (L1) is angle information, torque information for a servo motor of the electromechanical steering system (2), or information proportional to the torque of the servo motor of the electromechanical steering system (2). 3. The system according to 1. or 2. above, characterized in that one piece of first adjustment information (A1) is a driver moment threshold value, and the control unit (4) is configured to generate second driver moment information (L2) contributing to the change of the first steering control information (L1) provided from the driving assist system when the absolute value of the driver moment information (M) exceeds the driver moment threshold value. 4. The system according to any one of 1 to 3 above, characterized in that the second adjustment information (A2) is overriding steering toughness information which is a measure of the steering resistance that a driver must overcome to override the steering behavior set by the driving assist system (3) to perform overriding steering. 5. The system according to 4. above, characterized in that the control unit (4) is configured to be able to adjust the feedback control behavior of the first feedback control unit (5) of the control unit (4) based on the second adjustment information (A2). 6. The system according to any one of 1. to 5. above, characterized in that the control unit (4) is configured to receive one piece of first and one piece of second adjustment information (A1, A2), provided that one of the two pieces of adjustment information (A1, A2) is a fixed value and the other piece of adjustment information is a value depending on the driving state or driving situation, or both the first and second adjustment information (A1, A2) are values depending on the driving state or driving situation. 7. The system according to any one of 3. to 6. above, characterized in that the control unit (4) is configured such that the first feedback control unit (5) can receive a moment difference (DM) having an absolute value reduced by the driver moment threshold from the time when the absolute value of the driver moment information (M) is less than or equal to the driver moment threshold and becomes zero when the driver moment information exceeds the driver moment threshold. 8. The system according to any one of 1. to 7. above, characterized in that the first feedback control unit (5) has an absolute value characteristic curve that monotonically decreases above the cut-off frequency. 9. The system according to 8. above, characterized in that the first feedback control unit (5) has a feedback control behavior related to a PT1 controller. 10. The system according to any one of 1. to 9. above, characterized in that the first feedback control unit (5) has a feedback control behavior such that the moment difference (DM) supplied as an input value to the first feedback control unit (5) is reduced by the change of the first steering control information (L1) by the second steering control information (L2). 11. For the case where the first steering control information (L1) is angle information, yaw rate information, or curvature value information, the setting moment information of the steering angle feedback control means for the servo motor of the electromechanical steering system (2), or information proportional to the setting moment information, is used as the steering angle information, and the yaw rate information or curvature value information is used as the second steering control information (L2). A second feedback control unit (6) is provided, which is configured to be able to perform the above. The system according to any one of 1. to 10. 12. The second feedback control unit (6) is configured to be able to receive the setting moment information weighted by the activation factor (AF) of the steering angle feedback control means for the servo motor of the electromechanical steering system (2), provided that the activation factor (AF) is provided from the first feedback control unit (5). The system according to 11. 13. The second feedback control unit (6) is configured to receive the second adjustment information (A2) and be able to adjust the feedback control behavior of the second feedback control unit (6) based on the second adjustment information (A2). The system according to any one of 11. to 12. 14. The second feedback control unit (6) has an absolute value characteristic curve that monotonically decreases above the cut-off frequency and / or a feedback control behavior related to a PT1 controller. The system according to any one of 11. to 13. 15. A method for controlling the electromechanical steering means (2) for a vehicle, including a driving assist system (3) that provides one piece of first steering control information (L1) and a control unit (4) equipped with a first feedback control unit (5). The driving unit (4) receives driver moment information (M) applied by a human driver to steering and also receives adjustment information (A1, A2) depending on at least one driving state and / or driving situation, provided that the control unit (4) provides second steering control information (L2) depending on the driver moment information (M) and the at least one adjustment information (A1, A2), provided that the system (1) provides, to the steering system (2) of the vehicle, one modified steering control information (L3) based on the first and second steering control information (L1, L2), based on which the steering operation of the electromechanical steering system (2) is carried out. Method.

Description of Symbols

[0095] 1 System 2 Steering System 3 Driving Assist System 3,1 Peripheral Recognition Unit 3.2 Trajectory Planning Unit 3.3 Trajectory Tracking Feedback Control 3.4 Steering Angle Feedback Control Means 4 Control Unit 4.1 Absolute Value Unit 4.2 Subtraction Point 5 First Feedback Control Unit 6 Second Feedback Control Unit 7 Unit 8 Addition Point 9 Addition Point A1 First Adjustment Information A2 Second Adjustment Information AF Activation Factor DI Torque Information L1 First Steering Control Information L2 Second Steering Control Information L3 Third / Changed Steering Control Information L4 Fourth Steering Control Information M Driver Moment Information DM Moment Difference S1 First Interface S2 Second Interface SB Safety Barrier φ 設定 Set Steering Angle Information

Claims

1. A system for controlling an electromechanical steering means (2) for a vehicle, comprising a driving assist system (3) configured to generate one piece of first steering control information (L1), and a control unit (4) comprising at least one first feedback control unit (5), wherein the control unit (4) has a first interface (S1) configured to receive driver moment information (M), and at least one second interface (S2) configured to receive at least one piece of adjustment information (A1, A2) depending on a driving state and / or a driving situation, the control unit (4) is configured to provide second steering control information (L2) depending on the driver moment information (M) and at least one piece of adjustment information (A1, A2), and the system (1) is configured to provide the steering system (2) of the vehicle with one piece of modified steering control information (L3) based on the first and second steering control information (L1, L2), based on which the steering operation of the electromechanical steering system (2) is carried out, one piece of first adjustment information (A1) is a driver moment threshold value, and the control unit (4) is configured to generate second driver moment information (L2) contributing to the modification of the first steering control information (L1) provided by the driving assist system when the absolute value of the driver moment information (M) exceeds the driver moment threshold value, the first feedback control unit (5) is configured to receive a moment difference (DM) having an absolute value reduced by the driver moment threshold value from when the absolute value of the driver moment information (M) is smaller than or equal to the driver moment threshold value to zero when the driver moment information exceeds the driver moment threshold value, and has a feedback control behavior such that the moment difference (DM) supplied as an input value to the first feedback control unit (5) is reduced by adding the second steering control information (L2) to the first steering control information (L1). A system characterized by that.

2. The system according to claim 1, wherein the first steering control information (L1) is angle information, torque information for a servo motor of the electromechanical steering system (2), or information proportional to the torque of the servo motor of the electromechanical steering system (2).

3. The system according to claim 1 or 2, characterized in that the second adjustment information (A2) is a steering resistance that the driver must overcome the steering behavior set by the driving assistance system (3) for the steering operation made by the driver.

4. The system according to claim 3, characterized in that the control unit (4) is configured to be able to adjust the feedback control behavior of the first feedback control unit (5) of the control unit (4) based on the second adjustment information (A2).

5. The control unit (4) is configured to receive one first and one second adjustment information (A1, A2), provided that one of the two adjustment information (A1, A2) is a fixed value, and the other adjustment information is a value depending on the driving state or driving situation, or both the first and second adjustment information (A1, A2) are values depending on the driving state or driving situation. The system according to any one of claims 1 to 4.

6. The system according to any one of claims 1 to 5, characterized in that the first feedback control unit (5) has an absolute value characteristic curve that monotonically decreases above the cut-off frequency.

7. The system according to claim 6, characterized in that the first feedback control unit (5) has a feedback control behavior related to a controller having an absolute value characteristic curve that monotonically decreases above the cut-off frequency.

8. For the case where the first steering control information (L1) is angle information, yaw rate information or curvature value information, the setting moment information of the steering angle feedback control means for the servo motor of the electromechanical steering system (2), or information proportional to the setting moment information, is used as the steering angle information, and the yaw rate information or curvature value information is used as the second steering control information (L2). A second feedback control unit (6) configured to be able to do so is provided. The system according to any one of claims 1 to 7.

9. The system according to claim 8, characterized in that the second feedback control unit (6) is configured to be able to receive the setting moment information weighted by the gain factor (AF) of the steering angle feedback control means for the servo motor of the electromechanical steering system (2), provided that the gain factor (AF) is provided from the first feedback control unit (5).

10. The system according to claim 8 or 9, characterized in that the second feedback control unit (6) is configured to receive second adjustment information (A2) and adjust the feedback control behavior of the second feedback control unit (6) according to the second adjustment information (A2).

11. The system according to any one of claims 8 to 10, characterized in that the second feedback control unit (6) has an absolute value characteristic curve that monotonically decreases above the cut-off frequency and / or a feedback control behavior related to a controller having an absolute value characteristic curve that monotonically decreases above the cut-off frequency.

12. A method for controlling an electromechanical steering means (2) for a vehicle, comprising a driving assist system (3) that provides one piece of first steering control information (L1) and a control unit (4) that includes a first feedback control unit (5), wherein the control unit (4) receives driver moment information (M) applied by a human driver to the steering and receives at least one piece of adjustment information (A1, A2) depending on the driving state and / or driving situation. However, the control unit (4) provides second steering control information (L2) depending on the driver moment information (M) and at least one piece of adjustment information (A1, A2). However, the system (1) according to any one of claims 1 to 11 provides, to the steering system (2) of the vehicle, one piece of modified steering control information (L3) based on the first and second steering control information (L1, L2), based on which the steering operation of the electromechanical steering system (2) is performed. Method.

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