Improved determination of torque to be applied in electric power steering system

Abstract

The invention relates to a method for determining a torque to be applied in an electric steering system (26) of a steering system (28) of a host vehicle (10) having at least one steering support function acting on the electric steering system (26), comprising the following steps: receiving a requested torque from the at least one steering support function, determining a torque applied to the steering system (28) by the human driver, determining an intention of the human driver to apply the torque to the steering system (28), and determining a torque to be applied in the electric steering system (26) based on the torque requested from the at least one steering support function, the determined torque applied to the steering system (28) by the human driver, and the determined intention of the human driver to apply torque to the steering system (28). The invention also relates to a corresponding electric power steering system (26) for determining a torque to be applied to a steering system (28) of an own vehicle (10) having at least one steering support function acting on the electric power steering system (26). The invention also relates to a steering support system (12) comprising the aforementioned electric steering system.

Description

Technical Field

[0001] The invention relates to a method for determining a torque to be applied in an electric steering system of a steering system of an ego vehicle, the ego vehicle having at least one steering support function acting on the electric steering system, the method comprising the step of receiving a requested torque from the at least one steering support function.

[0002] The present invention also relates to an electric steering system for determining a torque to be applied to a steering system of an ego vehicle, the ego vehicle having at least one steering support function acting on the electric steering system, comprising a control unit and a drive unit, which is controlled by the control unit to apply the determined torque to the steering system, wherein the control unit receives a requested torque from at least one steering support function.

[0003] Furthermore, the invention relates to a steering support system, in particular as a lane centering system or lane keeping system, comprising an electric steering system as described above. Background Art

[0004] Different kinds of driving support systems are known, for example supporting a human driver when driving the ego vehicle. Such driving support systems supporting the human driver are generally referred to as ADAS (Advanced Driver Assistance Systems). Other driving support systems may provide autonomous driving functions and / or provide support to the autonomous driving system of the ego vehicle. For fully autonomous driving, different levels of autonomous driving may be applied, up to level 5.

[0005] In this regard, driving support systems include systems that provide support for vehicle steering, also known as steering assist functions (SAF) or steering support functions. In this context, steering assist functions, such as lane centering systems (LCS) or lane keeping systems (LKS), help the human driver to keep the ego vehicle on the intended driving path, typically in the center of the driving lane in the case of lane centering systems, or within the lane boundaries in the case of lane keeping systems. The SAF function influences the heading of the ego vehicle by commanding the steering system of the ego vehicle, in particular using the electric power steering (EPS).

[0006] EPS, sometimes also called Motor Driven Power Steering (MDPS), uses an electric motor instead of a conventional hydraulic system to assist the human driver of the ego vehicle. Sensors detect the steering wheel position and the torque applied in the steering column, and a computer module applies the assist torque via an electric motor connected to the steering gear or the steering column. This allows different kinds of assistance to be applied, including the features already mentioned, such as lane assistance, wind drift correction, etc. Typical EPS systems provide variable assistance, in particular depending on the speed of the ego vehicle. Therefore, different levels of assistance can also be applied, which can depend, for example, on the driving conditions, such as the speed of the ego vehicle.

[0007] Thus, when SAF is activated, the ego vehicle typically acts on the steering angle of the ego vehicle via the EPS system. However, in some situations, the driver of the ego vehicle may need or want to influence the driving path of the ego vehicle, such as to avoid potholes or maintain a distance to neighboring vehicles, which may be a different requirement from LCS or LKS. Other driving situations (in which the human driver of the ego vehicle may need or want to influence the driving path of the vehicle) include overtaking a truck, especially on highways, or even overtaking parked vehicles on urban / inter-urban roads. In order to change the driving path of the ego vehicle, the human driver may need to overcome the torque applied by the SAF system and additionally apply torque to change the driving path. This may not be easy or comfortable for the human driver because he / she may feel that the SAF is opposing his / her steering inputs as the SAF attempts to maintain its driving path determined by the SAF, such as in the case of LCS, positioning the ego vehicle at a predetermined reference position within the driving lane.

[0008] To overcome this problem, the SAF function monitors the steering wheel angle state, such as position and speed, and the torque applied by the human driver. In the event that the SAF determines that the human driver is overriding the SAF, the SAF can temporarily deactivate itself to allow the human driver to modify the driving path without the SAF opposing the driver's steering input. Alternatively, the SAF can temporarily apply a different torque, such as by scaling the torque based on the steering torque applied by the driver.

[0009] Setting the logic and thresholds for SAF deactivation based on human driver override is complex. More sensitive deactivation settings often result in false positive deactivations. Conversely, less sensitive settings reduce driver comfort. Reducing the torque applied by the SAF can provide more comfort to the driver, as the driver is able to steer more freely but still feel the SAF system intervention. However, both approaches can result in an undesirable change in the travel path of the ego vehicle in the event that the system performs a false positive deactivation of the SAF.

[0010] In this case, document US20150012182A1 relates to helping a vehicle driver in a bottleneck, including tasks of reading, evaluating and providing. In reading, a piece of information about a passable corridor in the bottleneck, a piece of information about the instantaneous trajectory of the vehicle in the bottleneck, and a piece of information about the steering torque currently applied by the driver to the vehicle steering are read. In evaluating, the various pieces of information about the corridor, trajectory and steering torque are evaluated by using known dimensions of the vehicle to identify an expected violation of the corridor by at least a part of the vehicle. In providing, when a violation is identified, a control signal is provided for a counter-torque that counteracts the steering torque to help the driver avoid the violation.

[0011] Each of the documents US20160152233A1 and US20180072310A1 involves evaluating driver behavior, including monitoring vehicle systems and driver monitoring systems to adapt to the driver's slow reaction time, lack of attention and / or alertness. For example, when it is determined that the driver is drowsy, the response system can modify the operation of one or more vehicle systems. The systems that can be modified include visual devices, audio devices, tactile devices, anti-lock braking systems, automatic pre-brake systems, brake assist systems, automatic cruise control systems, electronic stability control systems, collision warning systems, lane keeping assist systems, blind spot indicator systems, electronic pre-tensioning systems, and climate control systems.

[0012] Document US20190315403A1 relates to a vehicle control system installed on a vehicle, which includes an automatic steering control device, which is configured to perform automatic steering control, which determines a steering angle command value and controls the steering of the vehicle so that the actual steering angle follows the steering angle command value. The stop state detection device is configured to detect the stop state of the vehicle. The override detection device is configured to detect an override operation by the vehicle driver. When an override operation is detected in the stop state, the automatic steering control device prohibits the change of the actual steering angle caused by the automatic steering control until the vehicle starts to move. Summary of the invention

[0013] The object of the present invention is to provide a method for determining the torque to be applied in an electric steering system of a steering system, an electric steering system for determining the torque to be applied to a steering system, and a steering support system including the above-mentioned electric steering system, which increases the safety of the steering assist function and improves driver comfort when overriding the steering assist function by reducing false positive detections of such override.

[0014] This object is achieved by the independent claim. Advantageous embodiments are given in the dependent claims.

[0015] In particular, the present invention provides a method for determining a torque to be applied in an electric steering system of a steering system of a self-vehicle, the self-vehicle having at least one steering support function acting on the electric steering system, the method comprising the following steps: receiving a requested torque from at least one steering support function, determining a torque applied to the steering system by a human driver, determining the human driver's intention to apply torque to the steering system, and determining the torque to be applied in the electric steering system based on the torque requested from at least one steering support function, the determined torque applied to the steering system by the human driver, and the determined intention of the human driver to apply torque to the steering system.

[0016] The present invention also provides an electric steering system for determining a torque to be applied to a steering system of a self-vehicle, the self-vehicle having at least one steering support function acting on the electric steering system, comprising a control unit and a drive unit, which is controlled by the control unit to apply the determined torque to the steering system, wherein the control unit receives a requested torque from at least one steering support function, the control unit receives information about the torque applied to the steering system by a human driver, the control unit receives information about the human driver's intention to apply the torque to the steering system, and the control unit determines the torque to be applied to the steering system by controlling the drive unit based on the torque requested from at least one steering support function, the determined torque applied to the steering system by the human driver, and the determined intention of the human driver to apply the torque to the steering system.

[0017] The invention further provides a steering support system, in particular as a lane centering system or a lane keeping system, comprising the above-mentioned electric steering system.

[0018] The basic idea of ​​the invention is to confirm that the torque applied by the human driver to the steering system is applied intentionally. This is based on the determination of the torque applied by the human driver and the determination of the human driver's intention to apply the torque to the steering system. This enables an improved steering assist function, improves safety, improves driver comfort when overriding the steering assist function, and reduces the number of false positive detections of such overrides. The processing of the determined torque applied intentionally by the human driver to the steering system is different from the processing of the determined torque applied unintentionally to the steering system.

[0019] At least one steering support function, also referred to as a steering assist function (SAF), requests that a torque be applied to the steering system in order to follow a determined driving path, wherein the driving path is determined by the respective steering support function. Thus, when the SAF is activated, the SAF requests that the electric power steering (EPS) system apply a torque to the steering system in order to follow the driving path determined by the SAF.

[0020] However, in some cases, the human driver of the ego vehicle may need or want to follow a different driving path, for example to avoid a pothole or maintain distance from a neighboring vehicle. In this case, the human driver intentionally applies torque to the steering system, particularly by turning the steering wheel of the steering system. In this case, the human driver's intention to apply torque to the steering system is determined, so that the torque to be applied by the EPS system can be determined based on the expected or desired override of the torque requested by the SAF. In this case, the human driver can easily change the driving path of the ego vehicle based on the torque he / she applies.

[0021] However, in other cases, the human driver of the ego vehicle turns the steering wheel unintentionally and applies torque to the steering system unintentionally, for example when grabbing the steering wheel and moving. In this case, the lack of intention of the human driver to apply torque to the steering system is determined, so that the torque to be applied in the electric steering system can be determined based on the undesired or unintended application of torque to the steering system. As a result, an override of the SAF does not occur, a limited override can be performed, or even a counter-torque can be applied to the steering system in order to obtain the target defined by the corresponding driving support function. In each case, the total torque to be applied in the EPS system of the steering system of the ego vehicle is determined and applied. This determination is performed by the control unit of the electric steering system, which controls the drive unit to apply the determined torque to the steering system.

[0022] The ego vehicle refers to a vehicle having a steering system and an electric power steering system, for which the method for determining a torque to be applied in the electric power steering system is performed. The ego vehicle may be any kind of vehicle, including a passenger car (car or bus), a truck, a van, etc.

[0023] An electric power steering system, sometimes also called a motor-driven power steering (MDPS) system, is a system that uses an electric motor instead of a traditional hydraulic system to assist the human driver of the ego vehicle. Sensors detect the steering wheel position and the torque applied inside the steering column, and control the drive unit to apply torque to the steering system. An electric power steering system can be any electric or electronic power steering system.

[0024] A steering system is a system that functionally connects a steering wheel located in the passenger compartment of the ego vehicle and the steered wheels (usually the front wheels) of the ego vehicle. The steering wheel is mounted on a steering column, which transmits the steering movement to the steered wheels via a steering gear. In some vehicles, part of the steering system is provided electronically, also known as steer-by-wire. However, the principles of the present invention are equally applicable.

[0025] At least one steering support function provides support for steering the vehicle. In this context, a steering assistance function, such as a lane centering system (LCS) or a lane keeping system (LKS), helps the human driver to keep the ego vehicle on a predetermined driving path, typically in the center of the driving lane in the case of a lane centering system, or within the lane boundaries in the case of a lane keeping system. The SAF commands the steering system of the ego vehicle by requesting that torque of the electric steering system be applied to the steering system, thereby influencing the heading or driving path of the ego vehicle. The SAF thus acts on the EPS system. One or more steering support functions may be activated simultaneously, whereby multiple steering support functions jointly request torque from the EPS system, or each EPS system requests torque, the EPS system selecting the torque based on the different requests. Furthermore, one SAF may be permanently activated, while the other SAF is only activated in emergency situations, whereby the permanently activated SAF continuously requests torque and the SAF activated in an emergency situation overrides the permanently activated SAF in an emergency situation.

[0026] As an alternative to receiving a requested torque from the at least one steering supporting function, the EPS system may receive a requested steering angle from the at least one steering supporting function, which serves as a basis for determining the torque in accordance with the request from the at least one steering supporting function.

[0027] At least one steering support function and the electric steering system may be integrated in the host vehicle or implemented as independent systems connected via any type of data connection.

[0028] The torque applied by the human driver to the steering system may be determined differently, for example using a corresponding torque sensor or for example based on the electrical power required by the drive unit to apply the determined torque.

[0029] The human driver's intention to apply torque to the steering system is determined based on the human driver's behavior. Such behavior of the human driver can be intentional behavior, such as in the case where the human driver attempts to pick up an item from the floor of the passenger compartment, or unintentional behavior, such as in the case of a medical problem like a heart attack or other. In addition, the human driver's behavior can be easily determined based on, for example, the movement of the human driver's arms or legs. In other cases, the human driver's behavior can be determined based on, for example, the eye movements of the human driver's eyes of the ego vehicle. For example, it is known to determine a person's fatigue state based on eye movements.

[0030] Determining the torque to be applied in the electric steering system refers to determining the torque ultimately applied to the steering system. The torque is determined based on the torque requested from at least one steering support function, the torque determined to be applied to the steering system by the human driver, and the determined intention of the human driver to apply the torque to the steering system. Thus, in the absence of torque applied by the human driver, the torque requested from the at least one steering support function is applied by the electric steering system.

[0031] Determining the torque to be applied in the electric steering system based on the torque requested from at least one steering support function, the determined torque applied to the steering system by the human driver, and the determined intention of the human driver to apply the torque to the steering system may include the determined torque applied to the steering system by the human driver and the determined intention of the human driver to apply the torque to the steering system being used to determine, for example, whether the requested torque is applied or whether a different torque is applied. Determining the torque to be applied in the electric steering system based on the torque requested from at least one steering support function, the torque applied to the steering system by the human driver, and the intention of the human driver to apply the torque to the steering system does not require using any logical combination of all torques requested from at least one steering support function, torques applied to the steering system by the human driver, and the intention of the human driver to apply the torque to the steering system to calculate or determine the torque.

[0032] In the case of a human driver applying torque, the electric steering system performs a verification of the torque applied by the human driver based on the determined intention of the human driver to apply torque to the steering system. Therefore, in the case of intentional application of torque by the human driver, the torque to be applied in the electric steering system is determined based on the torque requested from at least one steering support function, the determined torque applied to the steering system by the human driver and the determined intention of the human driver to apply torque to the steering system. This can include determining the torque to be applied based on a requested torque, which is modified based on the torque applied to the steering system by the human driver and / or the determined intention of the human driver to apply torque to the steering system, as discussed in more detail below. This can even include a complete override or deactivation of the electric steering system, i.e., the electric steering system does not apply torque to the steering system.

[0033] The control unit determines a torque to be applied in the electric steering system of the steering system of the ego vehicle. The control unit controls the drive unit to apply the determined torque to the steering system. The control unit and the drive unit are connected by a control connection, which can be any type of analog or digital connection. The control unit can be any type of control unit suitable for the ego vehicle. Such control units are generally referred to as ECUs (Electronic Control Units) in the automotive field. The control unit can be shared for performing multiple tasks or applications. The control unit processes the received information as discussed further below.

[0034] The drive unit comprises, for example, an electric drive motor and applies a drive current based on a control signal received from a control unit. In this way, the drive unit can apply a determined torque to the steering system. The drive unit is usually connected to a steering column of the steering system and applies the torque on the steering column.

[0035] The intention of a human driver to apply torque to the steering system is usually based on the driver's focus on driving and actively and intentionally applying torque. In the case of a human driver of the self-vehicle being disturbed, distracted or in any other condition that does not allow the intentional application of torque, SAF can help overcome this situation and safely follow the predetermined driving path. In these cases, overriding SAF and the torque required by SAF may lead to dangerous driving situations. Especially when SAF is adjusted more on the comfort side, human drivers are prevented from applying torque unintentionally. However, based on the use of confirmation of the intention of determining the human driver to apply torque to the steering system, unintentional deactivation or overriding of SAF and the torque requested from SAF can be prevented. Therefore, verification based on the determination of the intention of the human driver to apply torque to the steering system allows a more comfortable driving experience to be provided on the one hand, with an improved ability to easily change the driving path of the self-vehicle for intentional changes in the driving path, and on the other hand, prevents unintentional changes in the driving path, such as by providing reliable resistance to the steering torque unintentionally applied by the human driver.

[0036] According to a modified embodiment of the present invention, the step of determining the human driver's intention to apply torque to the steering system includes determining the human driver's intention to apply torque to the steering system based on input received from a driver monitoring system. The driver monitoring system (DMS) can be a stand-alone system or integrated into the SAF. Any set of sensors and information sources can be used to measure or estimate the driver's intention, such as cameras, driver steering torque sensors, wearable devices, entertainment systems, hands-free systems. The driver's intention can be determined, for example, based on the driver's state and / or attention, which is typically provided as an output of the DMS. Therefore, an already existing driver monitoring system can be used to provide suitable input to determine the driver's intention to apply torque to the steering system. Such a DMS is known in the art and can determine, for example, fatigue of a human driver.

[0037] According to a modified embodiment of the invention, the electric power steering system comprises a driver monitoring system for determining information about the human driver's intention to apply torque to the steering system and providing this information to the control unit. The DMS may additionally provide outputs for use by other functions and / or systems of the ego vehicle, such as determining fatigue of the human driver and generating a warning in this case.

[0038] Alternatively, the driver monitoring system is arranged independently of the electric steering system and provides the electric steering system, in particular the control unit, with information about the driver's intention to apply torque to the steering system. Thus, the DMS can be a universal system used by different functions and / or systems of the ego vehicle.

[0039] According to a modified embodiment of the present invention, the step of determining the intention of the human driver to apply torque to the steering system includes determining the intention of the human driver to apply torque to the steering system based on at least one of the following: detecting the driver's hands at the steering wheel, detecting the driver's distraction / attention in driving the ego vehicle, detecting drowsiness and / or fatigue of the driver of the ego vehicle, detecting the health state of the driver of the ego vehicle, detecting dazzle of the driver of the ego vehicle, detecting the driver of the ego vehicle actively making a phone call, actively using a mobile device and / or actively using any device of the ego vehicle, such as an entertainment system, and detecting the environment of the ego vehicle, in particular with respect to the presence of potholes, parked cars or any kind of obstacles or other objects, in particular for verifying the determined intention of the human driver to apply torque to the steering system. In the case where the human driver's hands are at the steering wheel, it can be assumed that the human driver is paying attention and therefore will only intentionally apply torque to the steering system. Distraction and lack of attention can indicate a lack of intention to apply torque to the steering system, such as when the human driver performs a movement based on other activities and applies torque to the steering system due to such movement. Drowsiness or fatigue generally indicates or at least increases the likelihood of unintentional behavior, i.e., the human driver lacks the intention to apply torque to the steering system. Depending on the health state, a human driver may not be able to intentionally apply torque to the steering system, for example in the case of unconsciousness or death. The driver may be dazzled by sunlight and / or lights of oncoming vehicles. This can be identified, for example, based on specific movements of the human driver, such as closing eyes or other, which makes it difficult for the human driver of the ego vehicle to intentionally control the ego vehicle and therefore to intentionally apply torque to the steering system. Using a mobile phone or other mobile device while driving the ego vehicle is also a typical manifestation of human driver inattention. Therefore, the human driver will not intentionally apply torque to the steering system.

[0040] In general, the provided information is processed to determine information about the human driver, such as the human driver's attention or Figure 1 Based on the measured or estimated state, whether the human driver intends to apply torque to the steering system. In addition, the driver steering intention, i.e., the human driver's intention to apply torque to the steering system, can be determined / verified based on the detection of the environment surrounding the ego vehicle, i.e., externally detected objects / obstacles in the ego vehicle environment, such as potholes, parked vehicles, etc. Therefore, a determination can be performed to verify whether the determined intention of the human driver to apply torque to the steering system matches the external environment. For example, in the presence of a pothole or any obstacle in front of the ego vehicle, the human driver is likely to intentionally apply torque to the steering system.

[0041] According to a modified embodiment of the invention, the step of determining the intention of the human driver to apply torque to the steering system comprises determining the intention of the human driver to apply torque to the steering system as a quantified intention level, in particular between a minimum intention and a maximum intention, and the step of determining the torque to be applied in the electric steering system based on the torque requested from at least one steering support function, the determined torque applied to the steering system by the human driver and the determined intention of the human driver to apply torque to the steering system comprises determining the torque to be applied in the electric steering system based on the torque requested from at least one steering support function, the determined torque applied to the steering system by the human driver and the determined intention level. Thus, the determined intention level can be used to determine the torque to be applied in the electric steering system in a detailed manner, in particular by a calculation using the determined intention level as an input. In addition, the determined intention level can be compared with a threshold value, which can be defined, for example, to determine the torque in different ways. In particular, multiple thresholds can be defined to indicate, for example, high, medium, and low degrees of intention to determine and apply torque differently. In addition, the intention level enables a simple determination of the torque to be applied, for example based on the requested torque, and to be modified based on the intention level, for example as a simple mathematical calculation, in particular when the intention level is provided as a number. In particular, the level of intent may be determined based on input received from a driver monitoring system.

[0042] According to a modified embodiment of the present invention, the step of determining the torque to be applied in the electric steering system based on the torque requested from at least one steering support function, the determined torque applied to the steering system by a human driver and the determined intention of the human driver to apply the torque to the steering system comprises: determining the torque to be applied in the electric steering system by modifying the torque requested from at least one steering support function in a binary, stepwise or continuous manner based on the determined torque applied to the steering system by a human driver and / or the determined intention of the human driver to apply the torque to the steering system. Therefore, each of the torque applied to the steering system by the human driver and the intention of the human driver to apply the torque to the steering system can be used alone or in combination to modify the requested torque to determine the torque to be applied in the electric steering system. For example, one or more of the absolute value of the torque applied to the steering system by the driver, the difference between the requested torque and the torque applied to the steering system by the driver, the intention level of the driver's intention to apply the torque to the steering system, and their derivatives can be used to modify the requested torque to determine the torque to be applied in the electric steering system. The modification may be a simple switch between two states, such as requested torque and zero, or more states, such as requested torque, different percentages of requested torque and zero, or a calculation based on a mathematical formula, such as torque equals requested torque minus driver applied torque. The torque may in particular be modified by a factor, which may in particular be based on a determined torque applied to the steering system by a human driver and / or (in particular, and) a determined intention (in particular intention level) of the human driver.

[0043] According to a modified embodiment of the invention, the step of determining the torque to be applied in the electric steering system based on the torque requested from at least one steering support function, the determined torque applied to the steering system by the human driver and the determined intention of the human driver to apply the torque to the steering system comprises at least one of the following: providing a modified limit for the torque requested from at least one steering support function, in particular a saturation of the steering torque, determining the torque to be applied by scaling the torque requested from at least one steering support function by a factor, changing the algorithm responsible for determining the torque to be applied based on the torque applied to the steering system by the human driver, changing the feedback controller parameters in the feedback controller to determine the torque to be applied in the electric steering system, and changing the deactivation condition based on human driver override to deactivate the application of torque in the electric steering system. Some of the above options can be applied to adaptively change the "resistance" of the steering wheel to the driver's steering, i.e. the torque that must be applied by the human driver of the ego vehicle to be able to move the steering wheel as desired and steer the ego vehicle. Some of the above options can be applied to achieve an adaptive change of the conditions that lead to the deactivation of the electric steering system, i.e. the electric steering system does not apply torque. In this case, the limit of the torque requested from at least one steering support function can be modified in the corresponding steering support function or in the electric steering system or in both. Scaling the torque requested from at least one steering support function by a factor refers to determining the torque to be applied in the electric steering system using the torque value calculated with the requested torque as a starting point, and modifying the torque value by the factor, in particular according to the torque applied to the steering system by the human driver and / or the intention of the human driver to apply the torque to the steering system. In addition, the torque applied to the steering system by the human driver can be modified. The feedback controller enables the corresponding feedback control to smooth the torque to be applied in the electric steering system. The modification of the feedback controller parameters enables faster or slower adaptation to the torque to be applied in the electric steering system. The deactivation conditions for the application of torque in the deactivation electric steering system can be modified so that, for example, in the case where the human driver is not too focused on driving and therefore does not apply the steering torque intentionally, the deactivation conditions become more stringent to prevent deactivation from occurring. Conversely, for example, in the case where the human driver is highly focused on driving and therefore usually intentionally applies the steering torque, the deactivation conditions become less stringent to enable quick deactivation, assuming that as a prerequisite, the human driver intentionally applies the torque to the steering system. In general, there are different possibilities for determining the torque to be applied in an electric power steering system. These possibilities can be applied individually or in any suitable combination.

[0044] According to a modified embodiment of the present invention, the step of determining the torque to be applied in the electric steering system based on the torque requested from at least one steering support function, the determined torque applied to the steering system by a human driver, and the determined intention of the human driver to apply the torque to the steering system includes determining the torque to be applied by scaling the torque requested from at least one steering support function by a factor. Specifically, scaling the torque requested from at least one steering support function by a factor may refer to or include determining the torque to be applied in the electric steering system using a torque value calculated with the requested torque as a starting point, and modifying the torque value with a factor, specifically depending on the torque applied to the steering system by the human driver and the intention of the driver to apply the torque to the steering system (in particular, the intention level). In other words, the factor may specifically depend on or be based on the torque applied to the steering system by the human driver and the intention of the driver to apply the torque to the steering system (in particular, the intention level).

[0045] According to a modified embodiment of the present invention, the torque to be applied in the electric steering system is to follow a determined driving path. Specifically, the driving path is determined by the corresponding steering support function. Specifically, it can be the center of the driving lane (for example, in the case of a lane centering system (or function)), or within a lane boundary (or a boundary of the driving lane) (for example, in the case of a lane keeping system (or function)). In particular, the torque to be applied in the electric steering system can be to keep the ego vehicle at the center of the driving lane or within the center of the driving lane. In particular, when the steering support function is active, the steering support function can request the electric steering system to apply torque to the steering system to follow the driving path determined by the steering support function.

[0046] According to a modified embodiment of the present invention, the steering support function can be a lane centering system (or function) or a lane keeping system (or function), in particular keeping the own vehicle on a predetermined driving path (for example, in the center of the driving lane in the case of a lane centering system (or function), or within the lane boundary in the case of a lane keeping system (or function)).

[0047] According to a modified embodiment of the present invention, the method includes a step of generating a warning to the human driver in the event of a mismatch between a torque applied to the steering system by the human driver and the determined intention of the human driver to apply the torque to the steering system. The mismatch between the torque applied to the steering system by the human driver and the determined intention of the human driver to apply the torque to the steering system refers to a situation where the human driver inadvertently applies the torque to the steering system. In this case, the warning can alert the human driver to prevent further unintentional application of torque to the steering system. The warning can be an auditory and / or visual warning, which can be generated using any type of user interface device of the self-vehicle.

[0048] According to a modified embodiment of the invention, the electric power steering system comprises at least one sensor which provides sensor information to the control unit for determining the intention of the human driver to apply torque to the steering system. The direct use of at least one sensor overcomes possible limitations of using known driver monitoring systems, which currently focus on the state / condition of the human driver. Thus, the electric power steering system can determine the intention of the human driver to apply torque to the steering system independently of these limitations.

[0049] According to a modified embodiment of the invention, at least one sensor providing sensor information for determining the human driver's intention to apply torque to the steering system to the control unit comprises at least one of the following: an optical camera, which is arranged in the passenger compartment of the ego vehicle, at least partially monitoring the driver of the ego vehicle, and a manual sensor, which is arranged in / at the steering wheel of the ego vehicle. The optical camera can be arranged to monitor the body / chest of the human driver, for example to determine the position of the body / chest of the human driver. A body / chest that deviates from the "normal" driving position can indicate that the human driver is inadvertently applying torque to the steering system, for example when the hand grasping the steering wheel follows the movement of the body / chest. The optical camera can be arranged to monitor the human driver's hands, for example to determine the position of the hands. When the hands are located at the steering wheel, this can indicate the human driver's intention to apply torque to the steering system. The same applies when the manual sensor recognizes that the human driver's hands are located at the steering wheel. The optical camera can be arranged to monitor the head / face of the human driver, for example to determine the viewing direction, expressions indicating fatigue or medical problems, abnormal positions of the head, for example in the case where the driver is bent over to grab an item, etc. The optical camera can be arranged to monitor the eyes of the human driver in particular, for example to determine the viewing direction, eye movements indicating, for example, fatigue or medical problems, etc. In addition, the optical camera can be arranged to monitor other occupants of the ego vehicle. For example, when the human driver is talking to another passenger, this can indicate that he / she is not focusing on driving the ego vehicle, and the torque applied by the human driver to the steering system is considered not to be intentionally applied.

[0050] According to a modified embodiment of the invention, the control unit receives the requested torque from a steering support system providing at least one steering support function, in particular a lane centering system or a lane keeping system.

[0051] The features and advantages described above with reference to the method according to the invention also apply to the electric power steering system according to the invention and to the steering support system according to the invention, and vice versa.

[0052] These and other aspects of the invention will become apparent and explained with reference to the embodiments described below. The various features disclosed in the embodiments may constitute an aspect of the invention alone or in combination. The features of different embodiments may be carried over from one embodiment to another. BRIEF DESCRIPTION OF THE DRAWINGS

[0053] In the attached picture:

[0054] Figure 1 shows a schematic diagram of an ego vehicle with a steering support system according to a first preferred embodiment, the steering support system comprising an environmental sensor and a control unit,

[0055] Figure 2 A method for determining the method to be applied to the Figure 1 An electric steering system for the torque of a steering system of an ego vehicle, the electric steering system comprising a control unit and a drive unit,

[0056] Figure 3 A top view of an ego vehicle moving along a driving path in the center of a lane between lane boundaries is shown, along with a pothole in front of the ego vehicle and an alternative driving path to avoid the pothole;

[0057] Figure 4 shows the method for determining the Figure 1 The steering system of the ego vehicle Figure 2 A first example of a method for applying a torque to an electric steering system of an ego vehicle, wherein a human driver of an ego vehicle intentionally applies a torque to the steering system, resulting in an override of a torque requested by a steering support system, which torque is applied as a torque in the electric steering system,

[0058] Figure 5 shows the method for determining the Figure 1 The steering system of the ego vehicle Figure 2 A second example of a method for applying torque to an electric steering system of an ego vehicle, wherein a human driver of the ego vehicle unintentionally applies torque to the steering system, causing the torque requested by the steering support system to be continuously applied as the torque in the electric steering system,

[0059] Figure 6 shows the method for determining the Figure 1 The steering system of the ego vehicle Figure 2 A third example of a method for determining a torque to be applied in an electric steering system of an ego vehicle, wherein a human driver of the ego vehicle intentionally applies torque to the steering system, resulting in the torque to be applied in the electric steering system being determined as the torque requested by the steering support system being reduced by a factor based on the level of intention and the torque applied by the human driver, and

[0060] Figure 7shows the method for determining the Figure 1 The steering system of the ego vehicle Figure 2 Flow chart of a method for determining a torque applied in an electric power steering system, wherein a steering support function acts on the electric power steering system. DETAILED DESCRIPTION

[0061] Figure 1 An ego vehicle 10 is shown with a steering support system 12 according to a first preferred embodiment. The ego vehicle 10 may be any kind of vehicle including a car, bus, truck, van, etc.

[0062] The steering support system 12 of the first embodiment implements a steering support function (SAF), which is, for example, a lane centering system (LCS). In an alternative embodiment, the steering support system 12 is a lane keeping system (LKS). Thus, the steering support system 12 supports the human driver of the ego vehicle 10 to keep the ego vehicle 10 in the center of the corresponding driving lane.

[0063] The steering support system 12 includes environmental sensors 14, 16 for monitoring the environment 18 of the ego vehicle 10. In detail, the steering support system 12 of the first embodiment includes a front laser radar-based environmental sensor 14, also referred to as a front laser radar, and an optical camera 16 directed to the front side of the ego vehicle 10. Therefore, when driving forward, as shown in the forward driving direction 20, the front laser radar 14 and the optical camera 16 monitor the surrounding environment 18 of the ego vehicle 10 in the driving direction 20 in front of the ego vehicle 10. Each of the environmental sensors 14, 16 generates sensor information, which may include raw data or pre-processed data. In alternative embodiments, the steering support system 12 may include different environmental sensors 14, 16, including any single environmental sensor 14, 16 or any combination of the same or different kinds of environmental sensors 14, 16 in the laser radar-based front environmental sensor 14, the optical camera 16 directed to the front side of the ego vehicle 10, and the front radar sensor.

[0064] The ego vehicle 10 of the first embodiment also includes a control device 22 and a data connection 24, which interconnects the environmental sensors 14, 16 and the control device 22. The control device 22 can be any type of control device 22 suitable for the ego vehicle 10. Such a control device 22 is generally referred to as an ECU (Electronic Control Unit) in the automotive field. The control device 22 can be shared to perform multiple tasks or applications. The control device 22 receives sensor information from the environmental sensors 14, 16 and processes the received sensor information as further discussed below. The sensor information can be provided from the environmental sensors 14, 16 of the ego vehicle 10 in any suitable manner and format. The sensor information can be pre-processed or raw sensor data.

[0065] The data connection 24 may be a dedicated connection between the environmental sensors 14, 16 and the control device 22, or a data bus. In addition, the data connection 24 may be a shared data connection 24 used by different types of devices of the ego vehicle 10, such as a multi-purpose data bus. The data connection 24 may be implemented as a CAN bus, a LIN bus, etc., for example. The data connection 24 may be a single data connection 24 connecting the environmental sensors 14, 16 and the control device 22. Although Figure 1 A single data connection 24 is depicted in FIG. 2 , but a plurality of data connections 24 or data buses may be provided in parallel for connecting the environmental sensors 14 , 16 to the control device 22 . In this case, the plurality of data connections 24 or data buses may be considered together as data connections 24 .

[0066] The sensor information from the environmental sensors 14, 16 is transmitted to the control device 22 via the data connection 24. Figure 1 A single control device 22 is depicted in FIG, but a plurality of separate devices may be provided which together implement the control device 22.

[0067] The ego vehicle 10 also includes an electric steering system 26 for determining a torque to be applied to a steering system 28 of the ego vehicle 10. The electric steering system 26 is sometimes also referred to as a motor driven power steering (MDPS) system. The steering support system 12 is connected to the electric steering system 26 and acts on the electric steering system 26 to apply a torque to the steering system 28. Thus, in addition to determining the torque, the electric steering system 26 also applies the torque to the steering system 28. The electric steering system 26 is shown together with the steering system 28 in FIG. Figure 2 middle.

[0068] Therefore, the electric steering system 26 comprises a control unit 30 for determining the torque to be applied to the steering system 28. The control unit 30 may be any type of control unit 30 suitable for the ego vehicle 10. The control unit 30 is connected to the control device 22 of the steering support system 12 via a data connection 24 in a manner not shown in the figure.

[0069] The electric steering system 26 further comprises a drive unit 32, which is connected to the control unit 30 via a control connection 34. The control unit 30 controls the drive unit 32 via the control connection 34, which may be any kind of analog or digital connection, to apply a determined torque to the steering system 28. Thus, the drive unit 32 comprises an electric drive motor to apply a drive current based on a control signal received from the control unit 30. In this way, the drive unit 32 applies a torque determined by the control unit 30 to the steering system 28.

[0070] The steering system 28 includes a steering wheel 36, a steering column 38, and a steering gear, which is not shown in the figure and provides a steering connection between the steering column 38 and the front wheels of the ego vehicle 10. The steering column 38 is rotatably held by a bearing 40. The steering column 38 can be rotated according to a rotation direction 42 by a drive unit 32, which is connected to the steering column 38 of the steering system 28 and applies a torque to the steering column 38.

[0071] The electric power steering system 26 also includes an interior optical camera 44 as a sensor for providing sensor information, as discussed in more detail below. The interior optical camera 44 is arranged in the passenger compartment of the ego vehicle 10. The interior optical camera 44 is connected to the control unit 30 via the data connection 24. In an alternative embodiment, the interior optical camera 44 is provided separately from the electric power steering system 26 for use by a different system of the ego vehicle 10.

[0072] According to the first embodiment, the steering support system 12 and the electric power steering system 26 are separately provided. In an alternative embodiment, the steering support system 12 and the electric power steering system 26 may be implemented integrally in the ego vehicle 10 .

[0073] Figure 7 A flow chart depicts a method according to a first embodiment for determining a torque to be applied in an electric steering system 26 of a steering system 28 of an ego vehicle 10, in the case where a steering support system 12 acts on the electric steering system 26. The method is performed with an ego vehicle 10 comprising a steering support system 12, a steering system 28 and in particular an electric steering system 26. Figure 3 Let’s discuss this method. Figure 3 Ego vehicle 10 is shown moving along driving path 46 in the center of driving lane 48 between lane boundaries 50 . Figure 3 Also shown is a pothole 52 in the forward travel direction 20 ahead of the ego vehicle 10 and an alternative travel path 54 that avoids the pothole 52 .

[0074] The method starts at step S100 by receiving a requested torque from the steering support system 12 .

[0075] Therefore, the control device 22 of the steering support system 12 receives sensor information from the front laser radar 14 and the optical camera 16 and determines a driving path 46 for driving in the center of the lane 48, such as Figure 3 The steering support system 12 determines the torque to be applied to the steering system 28 and sends a corresponding request to the electric steering system 26 to influence the driving path 46 of the ego vehicle 10. The steering support system 12 is permanently activated in the current driving state and permanently requests torque from the electric steering system 26.

[0076] The control unit 30 receives the requested torque from the electric power steering system 26 .

[0077] Step S110 involves determining the torque applied to the steering system 28 by the human driver.

[0078] The torque applied by the human driver to the steering system 28 may be determined differently, for example using a corresponding torque sensor or for example based on the electrical power required to apply the torque by the drive unit 32. Therefore, the control unit 30 receives information about the torque applied by the human driver to the steering system 28 from a corresponding sensor or for example as feedback information from the drive unit 32.

[0079] Step S120 involves determining the human driver's intent to apply torque to the steering system 28 .

[0080] The human driver's intention to apply torque to the steering system 28 is determined based on the human driver's behavior, which can be intentional behavior, such as when the human driver attempts to pick up an item from the floor of the passenger compartment, or unintentional behavior, such as when tired or suffering from a medical problem like a heart attack or other. Therefore, the human driver's intention to apply torque to the steering system 28 is generally based on the driver's focus on driving and actively and intentionally applying torque. In the event that the human driver of the ego vehicle is distracted, distracted, or in any other condition that does not allow for intentional application of torque, the steering support system 12 safely follows the predetermined driving path 46 and he / she has no intention to apply torque to the steering system 28.

[0081] Thus, the electric steering system 26 receives a camera image as sensor information provided from the interior optical camera 44 as a sensor to at least partially monitor the human driver of the ego vehicle 10. The interior optical camera 44 may be arranged to monitor the body / chest of the human driver, for example to determine the position of the body / chest of the human driver. A body / chest that deviates from a "normal" driving position may indicate that the driver has inadvertently applied torque to the steering system 28, for example when the hand gripping the steering wheel 36 follows the movement of the body / chest. The interior optical camera 44 may be arranged to monitor the hands of the human driver, for example to determine the position of the hands. When the hands are at the steering wheel 36, this may indicate the human driver's intention to apply torque to the steering system 28. The interior optical camera 44 may be arranged to monitor the head / face of the human driver, for example to determine the direction of viewing, expressions indicating fatigue or medical problems, abnormal positions of the head, for example when the driver is bent over to grab an item, etc. The interior optical camera 44 may be arranged to monitor the eyes of the human driver in particular, for example to determine the direction of viewing, eye movements indicating, for example, fatigue or medical problems, etc. Further, the interior optical camera 44 may be arranged to monitor other occupants of the ego vehicle 10. For example, when the human driver is talking to another passenger, this may indicate that he / she is not focused on driving the ego vehicle 10, and the torque applied to the steering system 28 by the human driver is considered not to be intentionally applied. In addition, when the human driver is checking his / her mobile phone or even using the vehicle's infotainment system (GPS, radio, etc.), this may indicate that he / she is not focused on driving the ego vehicle 10, and the torque applied to the steering system 28 by the human driver is considered not to be intentionally applied. Any of the above actions may be performed alone or in combination to monitor the human driver and determine the human driver's intention to apply torque to the steering system 28.

[0082] In particular, as already partially mentioned above, information about the human driver of the ego vehicle may be processed to determine the human driver's intention to apply torque to the steering system 28 based on at least one of the following: detecting the driver's hands at the steering wheel 36, detecting the driver's distraction / attention to driving the ego vehicle 10, detecting drowsiness and / or fatigue of the driver of the ego vehicle 10, detecting the health state of the driver of the ego vehicle 10, detecting glare of the driver of the ego vehicle 10, and detecting that the driver of the ego vehicle 10 is actively making a phone call, actively using a mobile device, and / or actively using any device of the ego vehicle 10 (e.g., an entertainment system). In the case where the human driver's hands are at the steering wheel 36, it may be assumed that the human driver is paying attention and will therefore only intentionally apply torque to the steering system 28. Distraction and lack of attention may indicate a lack of intention to apply torque to the steering system 28, such as when the human driver performs a movement based on other activities and torque is applied to the steering system 28 as a result of such movement. Drowsiness or fatigue generally indicates or at least increases the likelihood of unintentional behavior, i.e., the human driver's lack of intention to apply torque to the steering system 28. Depending on the health state, a human driver may not be able to intentionally apply torque to the steering system 28, such as in the case of unconsciousness or death. The driver may be dazzled by sunlight and / or lights of oncoming vehicles. This can be identified, for example, based on specific movements of the human driver, such as closing the eyes, which makes it difficult for the human driver of the ego vehicle 10 to intentionally control the ego vehicle 10 and therefore difficult to intentionally apply torque to the steering system 28. Using a mobile phone or other mobile device while driving the ego vehicle 10 is also a typical indication of a human driver's inattention. Therefore, the human driver will not intentionally apply torque to the steering system 28.

[0083] Control unit 30 receives information about the human driver's intention to apply torque to steering system 28 and determines the human driver's intention to apply torque to steering system 28 as a quantified intention level based on the above criteria, specifically between a minimum intention and a maximum intention.

[0084] Step S130 involves determining a torque to be applied in the electric power steering system 26 based on the torque requested from the steering support system 12, the determined torque applied to the steering system 28 by the human driver, and the determined intention of the human driver to apply torque to the steering system 28. The control unit 30 determines the torque to be applied to the steering system 28.

[0085] Furthermore, the determined torque is applied by the control unit 30 , which controls the drive unit 32 according to the determined torque.

[0086] The torque to be applied in the electric steering system 26 is determined by modifying the torque requested from the steering support system 12 in a binary, stepwise, or continuous manner based on the determined torque applied by the driver to the steering system 28 and / or the determined intention of the driver to apply torque to the steering system 28, wherein the determined intention level serves as the human driver's intention to apply torque to the steering system 28. Thus, each of the torque applied by the human driver to the steering system 28 and the human driver's intention to apply torque to the steering system 28 may be used alone or in combination to modify the requested torque to determine the torque to be applied in the electric steering system 26.

[0087] In the absence of an intentional application of torque to the steering system 28 by the human driver of the ego vehicle 10, an override of the torque requested by the SAF steering support system 12 does not occur. Thus, based on a determination of the human driver's intention to apply torque to the steering system, an unintentional deactivation or override of the steering support system 12 or the torque requested by the steering support system 12 is prevented. This refers to, for example, an intention level of zero and to a binary modification of the requested torque.

[0088] Otherwise, one or more of the absolute value of the torque applied by the human driver to the steering system 28, the difference between the requested torque and the torque applied by the human driver to the steering system 28, the level of intent of the human driver to apply torque to the steering system 28, or a derivative thereof may be used to modify the requested torque to determine the torque to be applied in the electric power steering system 26. The modification may be a simple switch between two or more states, such as a requested torque, a different percentage of the requested torque, and zero, or a calculation based on a mathematical formula, such as torque equals requested torque minus driver applied torque.

[0089] In particular, determining the torque to be applied in the electric steering system 26 also includes one or more of the following: providing a modified limit for the torque requested from the steering support system 12, i.e., saturation of the steering torque, determining the torque to be applied by scaling the torque requested from at least one steering support function by a factor, changing an algorithm responsible for determining the torque to be applied based on the torque applied to the steering system 28 by the human driver, changing a feedback controller parameter in a feedback controller to determine the torque to be applied in the electric steering system 26, and changing a deactivation condition based on a human driver override to deactivate the application of torque in the electric steering system 26. Some of the above options may be applied to adaptively change the "resistance" of the steering wheel 36 to the driver's steering, i.e., the torque that must be applied by the human driver of the ego vehicle 10 to be able to move the steering wheel 36 as desired and steer the ego vehicle 10. Some of the above options may be applied to achieve an adaptive change of the conditions that lead to the deactivation of the electric steering system 26, i.e., the electric steering system 26 at least temporarily not applying torque.

[0090] The above-mentioned limitation of the torque requested from the steering support system 12 can be modified in the corresponding steering support function or in the electric steering system 26 or in both. Scaling the torque requested by the steering support system 12 by a factor refers to determining the torque to be applied in the electric steering system 26 as a starting point, wherein the torque value is calculated with the requested torque, and the torque value is modified by the factor, in particular according to the torque applied by the driver to the steering system 28 and / or the driver's intention level to apply the torque to the steering system 28. The feedback controller enables the corresponding feedback control to smooth the torque to be applied in the electric steering system 26. The deactivation conditions of the torque application in the electric steering system 26 can be modified to be more stringent to prevent deactivation from occurring, or less stringent to achieve rapid deactivation. These possibilities can be applied alone or in any suitable combination.

[0091] Step S140 involves generating a warning to the human driver if a mismatch is determined between the torque applied by the human driver to the steering system 28 and the determined intent of the human driver to apply torque to the steering system 28 .

[0092] The mismatch between the torque applied by the human driver to the steering system 28 and the determined human driver's intention to apply torque to the steering system 28 refers to a situation in which the human driver unintentionally applies torque to the steering system 28, as discussed in detail above. The warning can be an audible and / or visual warning, which can be generated using any type of user interface device of the ego vehicle 10.

[0093] Will then refer to Figures 4 to 6 Discuss three possible applications of the above method.

[0094] Figure 4 Referring to a first example, different torque processes are shown in the figure above. First, the torque 56 requested by the steering support system 12 is shown, which runs together with the torque 60 determined by the electric power steering system 26 until the time t d Therefore, the steering support system 12 actively steers the ego vehicle 10 to follow Figure 3 Driving path 46 is shown. Figure 4 Also shown is the torque 58 applied by the human driver of the ego vehicle 10. The torque 58 applied by the human driver is small before time t1, referenced to a phase 62 where there is no torque 58 applied by the human driver. Thus, the human driver is holding the steering wheel 36, but is not actively trying to apply torque to the steering system 28 via the steering wheel 36.

[0095] However, torque 58 applied by the human driver increases starting at time t1 as the human driver begins actively applying torque 58 to steering system 28 via steering wheel 36. In this example, assume that the human driver intentionally wants to travel along alternate travel path 54, for example, due to the presence of pothole 52 in travel lane 48.

[0096] The control unit 30 processes the received torque 56 requested by the steering support system 12, the torque 58 applied by the human driver, and the camera image received from the interior optical camera 44. The control unit 30 determines the level of the human driver's intention to apply the torque 58 on the steering system 28. In case the control unit 30 receives information about external detected objects / obstacles (such as potholes 52, parked vehicles, etc. located in the environment 18 of the ego vehicle 10), the control unit 30 may process the information to verify / confirm whether the human driver's determined intention to apply torque to the steering system matches the information about the external environment.

[0097] The control unit 30 determines the torque 60 applied to the electric power steering system 26 as the torque 56 requested by the steering support system 12 until the time t d At time t d , the control unit 30 overrides the torque 56 requested by the steering support system 12 and determines the torque 60 to be applied in the electric steering system 26 to be zero, so that only the torque 58 applied by the human driver acts on the steering system 28. d Depending on various conditions, and may vary over time based on the torque 58 applied by the human driver and the particular level of intent. d , the intention level reaches its maximum value.

[0098] Based on the override of the torque 58 applied by the human driver and the torque 56 requested by the steering assistance system 12 , the ego vehicle 10 deviates from the driving path 46 determined by the steering assistance system 12 . Figure 4 The lower graph of shows a position error 66 , which is the difference between the driving path 46 determined by the steering support system 12 and the alternative driving path 54 that was followed according to the intervention of the human driver.

[0099] At time t2, the human driver stops actively applying torque 58 to the steering system 28 via the steering wheel 36 and only holds the steering wheel 36. Figure 4In the example of , the override of the torque 56 requested by the steering support system 12 continues after time t2 when the human driver stops actively applying the torque 58 on the steering system 28. In another example, at time t2, the override ends and the control unit 30 returns to determine the torque 60 to be applied in the electric steering system 26 as the torque 56 requested by the steering support system 12 to reduce the position error 66.

[0100] Figure 5 Referring to the second example, different torque processes are shown in the figure above. First, the torque 56 requested by the steering support system 12 is shown, which operates together with the torque 60 determined by the electric power steering system 26. Therefore, the steering support system 12 actively steers the ego vehicle 10 to follow Figure 3 Driving path 46 is shown. Figure 5 Also shown is the torque 58 applied by the human driver of the ego vehicle 10. The torque 58 applied by the human driver is small before time t1, referenced to a phase 62 where there is no torque 58 applied by the human driver. Thus, the human driver is holding the steering wheel 36, but is not actively trying to apply torque to the steering system 28 via the steering wheel 36.

[0101] The torque 58 applied by the human driver increases starting at time t1 as the human driver begins actively applying the torque 58 on the steering system 28 via the steering wheel 36. In this example, it is assumed that the human driver is unintentionally applying the torque.

[0102] The control unit 30 processes the received torque 56 requested by the steering support system 12, the torque 58 applied by the human driver, and the camera image received from the internal optical camera 44. The control unit 30 determines the human driver's intention level to apply the torque 58 on the steering system 28. In this example, the intention level is low between time t1 and t2. Based on this, the control unit 30 determines the torque 60 to be applied in the electric steering system 26 as the torque 56 requested by the steering support system 12. The torque 60 to be applied in the electric steering system 26 is continuously determined as the torque 56 requested by the steering support system 12 because the torque 58 applied by the human driver together with the image level indicates that the human driver does not want to apply the torque 58 on the steering system 28.

[0103] Based on the torque 58 applied by the human driver and the torque 56 requested by the steering support system 12 , ie the torque 60 to be applied in the electric power steering system 26 , the ego vehicle 10 is driven according to Figure 5The position error 66 shown in the lower portion deviates from the travel path 46. Since the torque 56 requested by the steering support system 12 is the torque 60 to be applied in the electric steering system 26, the steering support system 12 continues to act on the electric steering system 26 to keep the ego vehicle 10 in the center of the travel lane 48. When the human driver stops to apply the torque 58 to the steering system 28, the torque 56 requested by the steering support system 12 causes the position error 66 to decrease, and the ego vehicle 10 returns to the travel path 46.

[0104] Figure 6 is a third example showing a different torque process. First, the torque 56 requested by the steering support system 12 is shown, which operates together with the torque 60 determined by the electric power steering system 26. Therefore, the steering support system 12 actively steers the ego vehicle 10 to follow Figure 3 Driving path 46 is shown. Figure 6 Also shown is the torque 58 applied by the human driver of the ego vehicle 10. The torque 58 applied by the human driver is small before time t1, referenced to a phase 62 where there is no torque 58 applied by the human driver. Thus, the human driver is holding the steering wheel 36, but is not actively trying to apply torque to the steering system 28 via the steering wheel 36.

[0105] The torque 58 applied by the human driver increases starting at time t1 as the human driver begins to actively apply the torque 58 on the steering system 28 via the steering wheel 36. In this example, it is assumed that the human driver is intentionally applying the torque.

[0106] The control unit 30 processes the received torque 56 requested by the steering support system 12, the torque 58 applied by the human driver and the camera image received from the internal optical camera 44. The control unit 30 determines the human driver's intention level to apply the torque 58 on the steering system 28. In this example, the intention level is high between times t1 and t2. Based on this, the control unit 30 determines the torque 60 to be applied in the electric steering system 26 as the torque 56 requested by the steering support system 12, which is reduced according to a factor based on the intention level and the torque 58 applied by the human driver. Therefore, Figure 5 Compared to the second example, the torque 60 applied in the electric power steering system 26 is reduced.

[0107] Reference numerals list

[0108] 10 Ego Vehicle

[0109] 12 Steering support system

[0110] 14 Front LiDAR, Environmental Sensors

[0111] 16 Optical cameras, environmental sensors

[0112] 18 Surroundings

[0113] 20 Forward direction

[0114] 22 Control Devices

[0115] 24 Data Connections

[0116] 26 Electric Power Steering System

[0117] 28 Steering system

[0118] 30 Control unit

[0119] 32 Drive Units

[0120] 34 Control Connection

[0121] 36 Steering Wheel

[0122] 38 Steering column

[0123] 40 Bearings

[0124] 42 Rotation direction

[0125] 44 Internal optical cameras, sensors

[0126] 46 driving routes

[0127] 48 driving lanes

[0128] 50 Lane Boundary

[0129] 52 Potholes

[0130] 54 Alternative driving routes

[0131] 56 Steering support system requested torque

[0132] 58 Torque applied by human driver

[0133] 60 Determined torque

[0134] 62 Phases without torque applied by the driver

[0135] 64 Phases with torque applied by the driver

[0136] 66 Position error

Claims

1. A method for determining a torque to be applied in an electric steering system (26) of a steering system (28) of an ego vehicle (10), the ego vehicle having at least one steering support function acting on the electric steering system (26), the method comprising the following steps: receiving a requested torque from at least one steering support function, determining the torque applied by the human driver to the steering system (28), determining the human driver's intention to apply torque to the steering system (28), and A torque to be applied in an electric power steering system (26) is determined based on a torque requested from at least one steering support function, a determined torque applied to the steering system (28) by a human driver and a determined intention of the human driver to apply torque to the steering system (28).

2. The method according to claim 1, characterized in that The step of determining the human driver's intent to apply torque to the steering system (28) includes determining the human driver's intent to apply torque to the steering system (28) based on input received from a driver monitoring system.

3. The method according to claim 1 or 2, characterized in that: The step of determining the human driver's intention to apply torque to the steering system (28) includes determining the human driver's intention to apply torque to the steering system (28) based on at least one of: - detecting the driver's hands at the steering wheel (36), - Detecting driver distraction / attention in driving the ego vehicle (10), - detecting drowsiness and / or fatigue of the driver of the ego vehicle (10), - detecting the health status of the driver of the ego vehicle (10), - detecting blinding of the driver of the ego vehicle (10), - detecting that the driver of the ego vehicle (10) is actively making a phone call, actively using a mobile device, and / or actively using any device of the ego vehicle (10), such as an entertainment system, and - Detecting the environment (18) of the ego vehicle (10), in particular with regard to the presence of potholes (52), parked cars or obstacles or other objects of any kind, in particular for verifying the determined intention of the human driver to apply torque to the steering system (28).

4. A method according to any preceding claim, characterised in that The step of determining the human driver's intention to apply torque to the steering system (28) includes determining the human driver's intention to apply torque to the steering system (28) as a quantified intention level, in particular between a minimum intention and a maximum intention, and The step of determining a torque to be applied in the electric steering system (26) based on a torque requested from the at least one steering support function, a determined torque applied to the steering system (28) by a human driver and a determined intention of the human driver to apply torque to the steering system (28) comprises determining a torque to be applied in the electric steering system (26) based on a torque requested from the at least one steering support function, a determined torque applied to the steering system (28) by a human driver and a determined intention level.

5. A method according to any preceding claim, characterised in that The step of determining the torque to be applied in the electric steering system (26) based on the torque requested from the at least one steering support function, the determined torque applied by the human driver to the steering system (28) and the determined intention of the human driver to apply the torque to the steering system (28) comprises determining the torque to be applied in the electric steering system (26) by modifying the torque requested from the at least one steering support function, in particular in a binary, stepwise or continuous manner, based on the determined torque applied by the human driver to the steering system (28) and / or the determined intention of the human driver to apply the torque to the steering system (28).

6. A method according to any preceding claim, characterised in that The step of determining a torque to be applied in the electric power steering system (26) based on the torque requested from the at least one steering support function, the determined torque applied to the steering system (28) by the human driver and the determined intention of the human driver to apply torque to the steering system (28) comprises at least one of the following: - providing a modified limitation of the torque requested from at least one steering support function, in particular saturation of the steering torque, - determining the torque to be applied by scaling the torque requested from at least one steering support function by a factor, - changing the algorithm responsible for determining the torque to be applied based on the torque applied to the steering system (28) by the human driver, - varying a feedback controller parameter in the feedback controller to determine a torque to be applied in the electric power steering system (26), and - Changing the deactivation condition based on human driver override to deactivate application of torque in the electric power steering system (26).

7. A method according to any preceding claim, characterised in that The step of determining the torque to be applied in the electric steering system (26) based on the torque requested from the at least one steering support function, the determined torque applied to the steering system (28) by a human driver and the determined intention of the human driver to apply the torque to the steering system (28) comprises scaling the torque requested from the at least one steering support function by a factor to determine the torque to be applied, in particular wherein the factor depends on or is based on the torque applied to the steering system (28) by the human driver and / or the intention of the human driver to apply the torque to the steering system (28).

8. A method according to any preceding claim, characterised in that The torque to be applied in the electric power steering system (26) is intended to follow a determined driving path, in particular the center of the driving lane (48) or within the lane boundaries.

9. A method according to any preceding claim, characterised in that The steering support function is a lane centering system or a lane keeping system.

10. A method according to any preceding claim, characterised in that The method includes the step of generating a warning to a human driver if a mismatch is determined between torque applied by the human driver to the steering system (28) and the determined intention of the human driver to apply torque to the steering system (28).

11. An electric steering system (26) for determining a torque to be applied to a steering system (28) of an ego vehicle (10), the ego vehicle having at least one steering support function acting on the electric steering system (26), the electric steering system comprising: a control unit (30), and A drive unit (32) controlled by a control unit (30) to apply a determined torque to a steering system (28), wherein: The control unit (30) receives a torque request from at least one steering support function, The control unit (30) receives information about the torque applied to the steering system (28) by the human driver, The control unit (30) receives information about the human driver's intention to apply torque to the steering system (28), and A control unit (30) determines a torque to be applied to the steering system (28) by controlling a drive unit (32) based on a torque requested from at least one steering support function, a determined torque applied to the steering system (28) by a human driver and a determined intention of the human driver to apply torque to the steering system (28).

12. The electric power steering system (26) according to claim 11, characterized in that The electric power steering system (28) includes at least one sensor (44) that provides sensor information to the control unit (30) for determining the human driver's intention to apply torque to the steering system (28).

13. The electric power steering system (26) according to claim 12, characterized in that: The at least one sensor providing sensor information to the control unit (30) for determining the human driver's intention to apply torque to the steering system (28) comprises at least one of: - an optical camera (44) arranged in the passenger compartment of the ego vehicle (10) for at least partially monitoring the driver of the ego vehicle (10), and - A manual sensor arranged in / at the steering wheel (36) of the ego vehicle (10).

14. The electric power steering system (26) according to any one of claims 11 to 13, characterized in that: The electric power steering system (26) includes a driver monitoring system for determining information about the human driver's intention to apply torque to the steering system (28) and providing this information to the control unit (30).

15. The electric power steering system (26) according to any one of claims 11 to 14, characterized in that: The control unit (30) receives a requested torque from a steering support system (12) providing at least one steering support function, in particular a lane centering system or a lane keeping system.

16. A steering support system (12), in particular as a lane centering system or lane keeping system, comprising an electric power steering system (26) according to any one of claims 1 to 15.

Images