IMPROVEMENT OF THE PERFORMANCE OF ADVANCED DRIVER ASSISTANCE SYSTEMS AND ACTIVE STEERING REACTIONS BY USE OF ESTIMATED ROAD BOMBING

Abstract

A system for improving the performance of an advanced driver assistance system (ADAS) and active steering feedback (ARS) by utilizing estimated road camber comprises a vehicle, sensors, and actuators capable of acquiring information about the vehicle or modifying the vehicle's steering behavior. A road camber estimation (RCE) application acquires the road angle of a road segment, determines which of at least two steering angle correction methods to use, and utilizes an output from at least one of the methods to calculate a steering angle correction.The system compensates for changes in the road angle by including the road angle in the calculations of the steering center angle, and the active steering feedback (ARS) of the RCE application actively and in real time brings the vehicle's steering wheel to a precise center position that matches the current trajectory of the vehicle on the road segment, regardless of the topography of the road segment.

Description

INTRODUCTION The present invention relates to advanced driver assistance systems (ADAS) for vehicles and in particular to systems and methods that utilize power steering systems to maintain the position of the vehicle on the road and within the lanes during autonomous and / or semi-autonomous driving. DE 10 2016 004 234 A1 discloses a method for lane keeping, whereby, for example, a change in the cross slope of the road is detected by means of a camera and a necessary steering angle correction is carried out automatically. A comparable method is known from DE 10 2018 105 804 A1, in which inertial sensors are used in addition to a camera. DE 10 2020 133 919 A1 also teaches the compensation of a road inclination determined by means of camera information, whereby a steering device is controlled taking into account a compensation yaw rate. DE 10 2019 103 090 A1 discloses a method for determining a center position taking into account the cross slope of the currently used roadway. For further background information, reference is made here to the publications US 2026 / 0 109 398 A1 or DE 10 2024 138 754 A1 and DE 10 2025 100 864 A1, which at least partly relate to the same inventiveness as the present invention and in which the same variables or variable names are used as in the present invention. While current ADAS systems fulfill their intended purpose of maintaining the vehicle's position within the lanes, there is a need for new and improved systems and methods to enhance ADAS functionality. These systems should return the steering to a precise center position consistent with the vehicle's straight-ahead movement, even when road camber, crown, gradient, or similar features are present. Furthermore, they should prevent continuous push / pull situations during ADAS operation, leading to improved driver confidence, increased system redundancy, robustness, reliability, and resilience. These new systems should maintain or reduce system complexity and manufacturing complexity without compromising the system's effectiveness and capabilities. BRIEF SUMMARY OF THE INVENTION According to the invention, a system for improving the performance of an advanced driver assistance system (ADAS) and active steering feedback (ARS) by utilizing the estimated road camber is presented, characterized by the features of claim 1. In another aspect of the present invention, the one or more sensors further comprise cameras and inertial measurement units (IMUs) capable of measuring movements and accelerations in at least three degrees of freedom. The one or more actuators comprise power steering actuators, which include at least one of the following: pumps for hydraulic power steering, electrohydraulic power steering, pneumatic power steering, and electropneumatic power steering, as well as electromechanical actuators for electromechanical power steering. The power steering actuators are capable of influencing at least one steering speed, one steering position, and one steering angle via the rack and pinion. In a further aspect of the present invention, the first control logic determines the activity status of the Lane Keeping Assist (LKA), Lane Centering Control (LCC), and ARS applications of the ADAS. If it is determined that the LKA, LCC, and ARS applications are inactive, it calculates a center angle for steering without considering the road angle. If it is determined that the LKA, LCC, and ARS applications are active, it acquires static and dynamic vehicle information as well as environmental information from one or more sensors. The first control logic further acquires and estimates a current road angle from the static and dynamic vehicle information and the environmental information. In a further aspect of the present invention, the first control logic also estimates a lateral force acting on the vehicle according to: where Tztotal, Fztotal and Nfx are calculated as follows: where L, Fr, rkp, Rnom, γ, τ are the length of the steering arm lever, the force of the rack, the offset of the steering axis relative to the wheel in the lateral direction, the nominal radius of the wheel, the kingpin angle and the camber angle, respectively. Xf, Xrs are the wheelbase of the vehicle from the center of gravity (CG) to the front and rear axles, respectively, m represents the unsprung mass of the vehicle and Zg the height of the vehicle's center of gravity. In a further aspect of the present invention, the first control logic also comprises control logic that estimates: a lateral force on the rear axle based on the yaw motion calculated by an inertial measurement unit (IMU) of one or more sensors, and an external yaw moment due to torque vectoring devices, such that the lateral acceleration of the vehicle is estimated using an estimate of lateral forces in the front and rear axles according to: control logic that compares the estimated lateral acceleration ây with the lateral acceleration aymeas measured by the IMU according to: if it is determined that the difference Δay between the estimated ây and the measured aymeas lateral accelerations reaches or exceeds the threshold T, it can be concluded that the vehicle is subjected to the road angle. In a further aspect of the present invention, the first control logic also comprises control logic that calculates the contribution of the road angle to the lateral forces (F_(y, road)) according to: for a constant road angle, and where (φL≠ φR) is for a variable road angle, and in general: In a further aspect of the present invention, the third control logic further comprises control logic that calculates a steering wheel center angle by subtracting an estimated resulting road-track steering wheel angle δcenter,road from a previously learned steering wheel center angle δcenter,learned according to: wherein the values ​​of the steering wheel center angle δcenter change gradually for small road-track camber angles and aggressively for large road-track camber angles. In a further aspect of the present invention, the fourth control logic further comprises control logic which, upon detection of a change in road angle, uses the calculated value of the steering center angle δcenter in ARS adjustments for adjustments of the steering wheel center position. According to the invention, a method for improving the performance of an advanced driver assistance system (ADAS) and active steering feedback (ARS) by using the estimated road camber is further presented, characterized by the features of claim 9. In a further aspect of the present invention, the method further comprises measuring motion and acceleration in at least three degrees of freedom with one or more inertial measurement units (IMUs), acquiring information about the vehicle's environment with one or more cameras, and providing power steering assistance for the vehicle with power steering actuators comprising at least one of the following: pumps for hydraulic power steering, electro-hydraulic power steering, pneumatic power steering, and electro-pneumatic power steering, as well as electromechanical actuators for electromechanical power steering. The power steering actuators are capable of influencing at least one steering speed, one steering position, and one steering angle via the rack and pinion. In another aspect of the present invention, the method further comprises determining the activity status of the Lane Keeping Assist (LKA), Lane Centering Control (LCC), and ARS applications of the ADAS; and, after determining that the LKA, LCC, and ARS applications are inactive, calculating a steering center angle without considering the road angle. After determining that the LKA, LCC, and ARS applications are active, the method acquires static and dynamic vehicle information as well as environmental information from one or more sensors; and acquires and estimates a current road angle from the static and dynamic vehicle information and the environmental information. In a further aspect of the present invention, the method further comprises the estimation of a lateral force acting on the vehicle according to: where Tztotal, Fztotal and Nfx are calculated as follows: where L, Fr, rkp, Rnom, γ, τ are the length of the steering arm lever, the force of the rack, the offset of the steering axis relative to the wheel in the lateral direction, the nominal radius of the wheel, the kingpin angle and the camber angle, respectively. Xf, Xrs are the wheelbase of the vehicle from the center of gravity (CG) to the front and rear axles, respectively, m represents the unsprung mass of the vehicle and Zg the height of the vehicle's center of gravity. In another aspect of the present invention, the method further comprises estimating a lateral force on the rear axle based on the yaw motion calculated by an inertial measurement unit (IMU) of one or more sensors, and an external yaw moment due to torque vectoring devices, such that the lateral acceleration of the vehicle is estimated using an estimate of lateral forces in the front and rear axles by comparing the estimated lateral acceleration ây with the lateral acceleration aymeas measured by the IMU; if it is determined that the difference Δay between the estimated ây and the measured aymeas lateral accelerations reaches or exceeds the threshold T, it is determined that the vehicle is subject to the road angle. In a further aspect of the present invention, the method further comprises calculating the contribution of the road angle to the lateral forces (F_(y, road)) according to: for a constant road angle, and where (φL≠ φR) represents a variable road angle, and in general: In a further aspect of the present invention, the method further comprises calculating a steering wheel center angle by subtracting an estimated resulting road-track steering wheel angle δcenter,road from a previously learned steering wheel center angle δcenter,learned according to: wherein the values ​​of the steering wheel center angle δcenter change gradually for small road camber angles and aggressively for large road camber angles. In another aspect of the present invention, the method further comprises, when a change in the road angle is detected, using the calculated value of the steering center angle δcenter in ARS adjustments for adjustments of the steering wheel center position. Another method for improving the performance of an Advanced Driver Assistance System (ADAS) and Active Steering Feedback (ARS) by using estimated road camber includes: the acquisition of static and dynamic information about a vehicle and the vehicle's environment using one or more vehicle sensors, comprising: measuring motion and acceleration in at least three degrees of freedom using one or more inertial measurement units (IMUs); and acquiring information about the vehicle's environment using one or more cameras.The method further comprises: modifying the static and dynamic behavior of the vehicle, including changing the steering angle and trajectory of the vehicle, by means of one or more actuators of the vehicle, wherein the one or more actuators are connected to a steering wheel and a rack of the vehicle, and the steering wheel is connected to steerable wheels of the vehicle via the rack, comprising: assisting the steering of the vehicle by means of power steering actuators comprising at least one of the following elements: pumps for hydraulic power steering, electro-hydraulic power steering, pneumatic power steering, and electro-pneumatic power steering, as well as electromechanical actuators for electromechanical power steering. The power steering actuators are capable of influencing at least one steering speed, one steering position, and one steering angle via the rack.The method further includes the execution of program code segments stored in the memory of a vehicle controller. The controller also includes a processor and input / output (I / O) ports. The controller's I / O ports are connected to one or more sensors and one or more actuators. The processor executes program code segments stored in memory. These program code segments receive information from the one or more sensors via the I / O ports and transmit instructions via the I / O ports to the one or more actuators to modify the vehicle's static and dynamic behavior.The program code includes a Road Camber Estimation (RCE) application with control logic for: determining the road camber angle of a road segment on which the vehicle is currently located, including: determining the activity status of the Lane Keeping Assist (LKA), Lane Centering Control (LCC), and ARS applications of the ADAS. If the LKA, LCC, and ARS applications are determined to be inactive, the RCE application calculates a steering center angle without adjusting for the road camber. If the LKA, LCC, and ARS applications are determined to be active, the application acquires static and dynamic vehicle information as well as environmental information from one or more sensors.The RCE application acquires and estimates a current road angle from the vehicle's static and dynamic information and environmental information, and estimates a lateral force acting on the vehicle according to: where Tztotal, Fztotal, and Nfx are calculated as follows: where L, Fr, rkp, Rnom, γ, and τ are the length of the steering arm lever, the rack force, the lateral offset of the steering axis relative to a tire, the nominal radius of the tire, the kingpin angle, and the camber angle, respectively. Xf and Xrs are the vehicle's wheelbase from the center of gravity (CG) to the front and rear axles, respectively, m represents the vehicle's unsprung mass, and Zg is the height of the vehicle's center of gravity.The RCE application estimates a lateral force on the rear axle based on the yaw motion calculated by an inertial measurement unit (IMU) of one or more sensors, and an external yaw moment due to torque vectoring devices as: so that the lateral acceleration of the vehicle is estimated using an estimate of lateral forces in the front and rear axles according to: compares the estimated lateral acceleration ây with the lateral acceleration aymeas measured by the IMU according to:. If it is determined that the difference Δay between the estimated ây and the measured aymeas lateral accelerations reaches or exceeds the threshold T, the RCE application concludes that the vehicle is subject to the road angle and calculates the contribution of the road angle to the lateral forces (F_(y, road)) according to: for a constant road angle, and where (φL≠ φR) is for a variable road angle, and in general: The RCE application determines which of at least two methods should be used for steering angle correction, including: pausing a learning phase for steering angle correction and using a previously learned value for steering angle correction to return the steering wheel to the center, giving priority to ADAS and avoiding constant correction by ADAS functions; and compensating for the effects of the road angle on lateral movement and calculating the steering wheel torque feedback.The RCE application calculates a steering angle correction from an output of at least one of at least two steering angle correction methods, comprising: calculating a steering wheel center angle by subtracting an estimated resulting road-track steering wheel angle δcenter,road from a previously learned steering wheel center angle δcenter,learned according to: wherein the values ​​of the steering wheel center angle δcenter change gradually for small road camber angles and aggressively for large road camber angles.The RCE application compensates for changes in the road angle, including: upon detection of a road angle change: using the calculated value of the steering center angle δcenter in the ARS settings to adjust the steering wheel center position; and incorporating the road angle in the calculations of the steering center angle to cause the RCE application's Active Steering Feedback (ARS) to actively and in real time return the steering wheel to a precise center position that matches the vehicle's current trajectory on the road segment, regardless of the topography of the road segment. In a further aspect of the present invention, the method comprises implementing the estimated road camber or estimated road angle as the estimated steering wheel center angle resulting from the road, wherein the estimated steering wheel center angle resulting from the road is an equivalent value of the road camber or road angle via calculations to compensate for the vehicle heading angle in order to maintain the straight-ahead driving of the vehicle in motion without intervention by the driver. Further areas of application will become apparent from the description given here. It should be understood that the description and the specific examples serve only as illustrations. BRIEF DESCRIPTION OF THE DRAWINGS The drawings described here are for illustrative purposes only. Fig. 1 is a schematic diagram of a system for improving the performance of Advanced Driver Assistance Systems (ADAS) and Active Steering Feedback (ARS) by utilizing estimated road camber according to an exemplary embodiment; Fig. 2 is a perspective partial rear view of a vehicle using the system of Fig. 1 in three different situations according to an exemplary embodiment; Fig. 3 is a flowchart showing the logical flow of a road camber estimation (RCE) application of the system of Fig. 1 according to an exemplary embodiment; and Fig. 4 is a simplified flowchart showing the implementation of the RCE application of Fig. 3 in an exemplary vehicle according to an exemplary embodiment. DETAILED DESCRIPTION The following description is for illustrative purposes only. Figure 1 schematically illustrates a system 10 for improving the performance of advanced driver assistance systems (ADAS) and active steering feedback by utilizing the estimated camber of the road surface 12. The system 10 includes a vehicle 14. The vehicle 14 is depicted as a passenger car, but it is clear that the vehicle 14 can be any type of vehicle 14, including cars, trucks, sport utility vehicles (SUVs), vans, motorhomes, semi-trailer trucks, articulated lorries, delivery vehicles (including those used in warehouses), tricycles, aircraft, amphibious vehicles, or other vehicles 14 of this type that travel on the ground. The terms “front”, “rear”, “inside”, “inwards”, “outside”, “outwards”, “above”, and “below” used here refer to the orientation of the vehicle 14 as shown in the drawings of the present application. Thus, “forward” refers to a direction towards the front of a vehicle 14, “backwards” to a direction towards the rear of a vehicle 14, “inside” and “inwards” to a direction towards the interior of a vehicle 14, “outside” and “outwards” to a direction towards the outside of a vehicle 14, “below” to a direction towards the underside of the vehicle 14, and “above” to a direction towards the top of the vehicle 14. The vehicle 14 has a steering wheel 16 or a handwheel that is connected, either directly or indirectly, to one or more racks 18 that can hold and adjust one or more steerable wheels 20 of the vehicle 14. The racks 18 of the vehicle 14 include power steering actuators 23, which include, among others: pumps for hydraulic assistance, electro-hydraulic assistance, pneumatic assistance, and / or electro-pneumatic assistance, and / or electromechanical actuators for electromechanical assistance, or the like. The power steering amplifies the torque inputs generated by the driver into the steering wheel 16 and applies the amplified torque inputs generated by the driver to steering settings or movements in one or more racks 18 of the vehicle 14.In some examples, only the front wheels 20A are steerable, while in other examples the rear wheels 20B or a combination of front and rear wheels 20A, 20B may also be steerable. In further examples, the steering functions of the vehicle 14 can be supplemented by torque vectoring capabilities of a (not specifically shown) drive system of the vehicle 14, so that the torque applied to one or more wheels 20 of the vehicle 14 can be distributed unevenly to generate a yaw moment in the vehicle 14 and thereby change the course or trajectory of the vehicle 14 on the roadway 12. One or more sensors 22 are integrated into the vehicle 14. The sensors 22 acquire static and dynamic information about the vehicle 14 and may include, among other things: electromagnetic (EM) sensors 22 such as cameras 24, infrared cameras, video cameras, LiDAR (light detection and ranging) sensors, RADAR (radio detection and ranging) sensors, SONAR (sound navigation and ranging) sensors, and similar devices. EM sensors 22, such as those mentioned above, can be used to determine the proximity of the vehicle 14 to other vehicles 14, to objects in the vicinity of the vehicle 14, and to determine the topography of the surface on which the vehicle 14 is traveling, as well as to detect road signs and the like. The sensors 22 may also include sensors 22 that are capable of directly and / or indirectly measuring the static and dynamic states of the vehicle 14, such as inertial measurement units (IMUs).inertial measurement units) 26, suspension sensors, ground clearance sensors for continuous damping control (CDC), sensors for semi-active damping suspension (SADS), air suspension sensors, global positioning system (GPS) sensors, wheel speed sensors 20 and / or brake sensors capable of measuring rotational speeds and / or torques currently acting on one or more of the wheels 20 and / or on a front axle 28 and / or on a rear axle 30 of the vehicle 14. The sensors 22 may also include throttle position sensors, accelerator pedal position sensors, steering position sensors and / or steering wheel angle sensors (SWAS) 32 capable of measuring at least one steering system position 33, one steering system rate 33 and one steering system speed 33, tire pressure monitoring system (TPMS) sensors.tire pressure monitoring system) and the like. The IMUs 26 can measure motion, acceleration, and the like in multiple degrees of freedom. In a specific example, the IMUs 26 can measure position, motion, acceleration, etc., in at least three degrees of freedom. Similarly, the SADS sensors can be IMUs 26 capable of measuring in three or more degrees of freedom. In some examples, the SADS might include accelerometers for suspension hubs, similar devices, or the like. The system 10 also includes one or more controllers 34 that communicate with the various sensors 22 and actuators 23 of the vehicle 14. The controllers 34 are integrated into the vehicle 14 and control various aspects of the static and dynamic behavior of the vehicle 14. The controllers 34 are, in particular, non-generalized electronic controllers with a pre-programmed digital computer or processor 36, a non-transient computer-readable medium or memory 38 used to store data such as control logic, software applications, instructions, computer code, data, lookup tables, and the like, and input / output (I / O) ports 40. The computer-readable media or memory 38 includes all types of media that a computer can access, such as...Read-only memory (ROM), random access memory (RAM), hard disk drive, compact disk (CD), digital video disc (DVD), or any other type of storage. Non-transient computer-readable memory 38 excludes wired, wireless, optical, or other communication links carrying transient electrical or other signals. Non-transient computer-readable memory 38 includes media on which data can be permanently stored and media on which data can be stored and subsequently overwritten, such as a rewritable optical disc or an erasable storage device. Computer code includes all types of program code, including source code, object code, and executable code. The processor 36 is configured to execute the code or instructions. The vehicle 14 may have additional controllers 34, such asa dedicated Wi-Fi controller, an engine control module, a transmission control module, a body control module, an infotainment control module, or similar. The I / O ports 40 can be configured to communicate via wired communication, wirelessly via Wi-Fi protocols according to IEEE 802.11X, or similar. The controller 34 also contains one or more applications 42. An application 42 is a software program configured to perform a specific function or group of functions. The applications 42 may contain one or more computer programs, software components, instruction sets, procedures, functions, objects, classes, instances, associated data, or parts thereof that are suitable for implementation in appropriate machine-readable program code. The applications 42 may be stored within the memory 32 or in additional or separate memory 32. Examples of applications 42 include audio or visual streaming services, games, browsers, social media, and so on. In other examples, the applications 42 are used by the system 10 to manage and control functions of the vehicle's body control system 14 or similar.In a specific example, one or more of the applications 42 define an ADAS application 44, at least part of which defines a road crown estimation application 46 that enhances the functionality of the ADAS application 44 in the vehicle 14, as described in more detail herein. The ADAS application 44 may include additional functions, subroutines, or the like, including, but not limited to, applications of lane keep assist 48, adaptive cruise control 48, lane centering control 50, and / or active return steering 52, which are capable of automatically and / or semi-automatically accelerating and braking the vehicle 14, as well as automatically and / or semi-automatically steering the vehicle 14. In Fig. 2 and Fig. 3, and with further reference to Fig. 1, the system 10 is schematically represented in three different operating states, which are designated in Fig. 2 by the numbers 100, 200 and 300 respectively, and in Fig. 3 by a corresponding flow diagram. The vehicle 14 shown in Fig. 2 in the first operating state 100 is depicted between the center 54 of the roadway 12 and the right edge 58. The second operating state 200 is depicted in the center 54 of the roadway 12 when the vehicle 14 changes from the right side or right lane 60 of the roadway across the center 54 of the roadway 12 to the left side or left lane 62 of the roadway 12. The third operating state 300 shows the vehicle 14 on the left lane 62 between the center 54 of the roadway 12 and the left edge 58' of the roadway 12. Figure 2 shows a rear view of the vehicle 14 on a cross-section of a section of the roadway 12. The section of the roadway 12 has a camber 64. The camber 64 is a curvature or slope of the surface of the roadway 12. The roadway 12 is typically provided with a camber, with the center 54 of the roadway 12 being higher than the left and right edges 58, 58' of the roadway 12, so that water can drain off the surface of the roadway 12, thereby reducing the risk of aquaplaning of vehicles 14 and the like, as well as the risk of water remaining on the surface of the roadway 12 for extended periods and causing water or frost damage to the roadway 12.However, the camber or crown 64 of the roadway 12 can cause the vehicle 14 to pull or drift slightly towards the left and right edges 58, 58' of the roadway 12, particularly if the surface of the roadway 12 is uneven. Accordingly, the system 10 of the present invention uses the RCE application 46 to account for and compensate for the pulling or drifting of the vehicle 14 due to the presence of roadway camber 64 or a camber during the vehicle 14's journey. The active steering feedback (ARS) function in vehicle 14 relies significantly on angle correction functions for the precise centering of the steering wheel 16 (and, more broadly, the steering system 33) of vehicle 14. For example, if vehicle 14 has been driving in the right lane 60, as shown in the first operating state 100, for a period during which an angle correction function has learned, adjusted, and provided a compensating change in the steering wheel angle 16, and temporarily suspends the implementation of the lane centering control (LCC) while changing lanes via the center 54 and the camber 64 (i.e., second operating state 200) to the left lane 62 (i.e., third operating state 300), the angle correction from the right lane 60 is no longer accurately correcting for the drift of vehicle 14 and must be adjusted for further driving in the left lane 62.This means that without relearning, the angle correction from the right lane 60, when applied to vehicle 14 while it is traveling in the left lane 62, would generate commands to the actuators 23 of vehicle 14's steering system 33. These commands would cause an inaccurate center position of the steering system 33 and the steering wheel 16, resulting in vehicle 14 drifting towards the left edge 58' of the left lane 62 and / or moving unpredictably, wandering within the left lane 62, oscillating within the left lane 62, or similar behavior. Accordingly, the RCE application 46 actively modifies and adjusts the functionality of LKA applications 48, LCC applications 50, and / or ARS applications 52 to maintain vehicle 14's position on the roadway 12 while actively, adaptively, and dynamically generating a center steering position. LCC applications 50 actively keep the vehicle 14 in the center of its current lane on the roadway 12 by continuously adjusting the position of the steering system 33. The LCC application 50 uses input from a variety of sensors 22, such as cameras 24, to detect lane markings 25 and, based on the position of the lane markings 25 relative to the vehicle 14, provides constant commands to the actuators 23 of the steering system. These actuators manipulate the steering speed, steering position, steering angle, and similar parameters to maintain the vehicle 14's position in the center or at a defined and constant distance between the left and right edges of the vehicle 14's current lane.It becomes clear that while vehicle 14 can be described as "centered" within a lane, its position when "centered" is not actually exactly between the left and right edges of the lane. Rather, the term "centered" can also encompass a position that has a certain offset from the left and / or right edge of the lane. This means that vehicle 14 may be slightly offset to one side of a lane when it is "centered." Such offsets can be practical and desirable for driver comfort, accident avoidance, and the like, by placing vehicle 14 in a position that is off-center within its current lane, away from oncoming traffic in an adjacent lane. Active Steering Return (ARS) applications 52 in an exemplary vehicle 14 utilize power steering systems 33, such as electric power steering (EPS), to ensure that the steering wheel 16 returns to a centered position after a turn. The ARS application 52 enhances driver comfort by providing a natural feel for steering inputs and outputs via the steering wheel 16. ARS applications 52 perform learning operations to adapt over time to different driving conditions and driver behaviors, including the use of adaptive control and disturbance monitoring functions. Adaptive control functions cause the system 10 to adjust parameters based on feedback from the steering sensors 22, such as SWAS 32, to optimize the return to center.In contrast, the functions of the disturbance observer serve to detect and compensate for external disturbances, such as unevenness of the road surface 12, and thus ensure a smooth return of the steering wheel 16. The LKA application 48 actively prevents the vehicle 14 from unintentionally drifting out of its current lane. The LKA application 48 intervenes when the system 10 detects that the vehicle 14 is about to cross a lane marking 25 without activating its turn signal. LKA applications 48 can provide a corrective steering system 33 via the steering actuators 23 connected to the rack 18 and, in some examples, issue a warning to the driver. The warning can include a vibration and / or an audible or visual notification that either automatically steers the vehicle 14 or prompts the driver to steer the vehicle 14 back into its current lane. While ADAS applications 44, such as LKA applications 48, LCC applications 50, etc., are active, the RCE application 46 interrupts the learning of the steering center angle to prevent an inaccurate implementation of the steering center position that would cause the vehicle 14 to drift within the lane. However, interrupting the learning of the steering angle can create a potential lateral hazard (i.e., drifting) in situations where the vertex or camber 64 of the roadway 12, or the angle or slope of the roadway 12, changes. To avoid such hazards, the roadway angle and the resulting mean steering angle are calculated separately and integrated into the ARS application 52 to actively and reliably compensate for off-center steering conditions when the magnitude or direction of the angle of the roadway 12 changes. With reference to Fig. 3 and with further reference to Fig. 1 and Fig. 2, the system 10 and the RCE application 46 are presented in more detail as a flowchart, comprising a series of logical steps. The RCE application 46 begins in block 400. Subsequently, in block 402, the RCE application 46 performs a measurement of the angle of the roadway 12. In block 402, the system 10 and the RCE application 46 measure a camber 64 and / or a slope of the roadway 12, including the magnitude and direction of the camber 64 and / or the slope, and transmit the measurement to the ARS application 52 via a Boolean interface. More specifically, in block 404, the system 10 and the RCE application 46 determine whether ADAS functions such as the LKA applications 48 and LCC applications 50 are active.After Block 404 has determined that the ADAS functions are active, the RCE application 46 proceeds to Block 406, where the RCE application 46 performs the detection and estimation of the road angle 12 or camber 64 based on information obtained from a series of inputs 408 from various sensors 22 of the vehicle 14, including information from camera 24 and IMU sensor 26. To avoid the effects of the road angle 12 on the lateral force estimation, the lateral force estimation can be performed based on a rack force 18 on the front axle 28 according to: where Tztotal, Fztotal, and Nfx can be calculated as follows: where L, Fr, rkp, Rnom, γ, τ are the length of the steering arm lever, the rack force 18 is the lateral offset of the steering axis relative to the wheel 20, the The nominal radius of the wheel is 20, as are the axle knuckle angle and the camber angle.Xf,Xr are the wheelbase of the vehicle 14 from the center of gravity (CG) to the front or rear axle 28 or 30 m, respectively, the unsprung mass of the vehicle 14 and Zg the height of the center of gravity of the vehicle 14. Similarly, the lateral force on the rear axle 30 can be estimated based on the yaw motion calculated by the IMU 26 and the external yaw moment due to the torque vectoring devices: The lateral acceleration of the vehicle 14 can therefore be estimated using the estimation of the lateral forces in the front and rear axles 28, 30 according to: and in comparison to the lateral acceleration measured by the IMU 26: If the difference Δay between the estimated ây and the measured aymeas lateral acceleration reaches or exceeds a threshold value T, it can be determined in Block 406 that the vehicle 14 is subjected to an angle of the roadway 12. It should be noted that the threshold value T is a calibratable value that can vary from vehicle 14 to vehicle 14 and / or from situation to situation. In some examples, the threshold value T can also be variable. In situations where the vehicle 14 is exposed to an angle of the roadway 12 which is so large that the difference between the estimated and the measured lateral acceleration reaches or exceeds the threshold value T, the contribution of the angle of the roadway 12 to the lateral forces can be calculated as follows: where (φ = φL= φR) represents a constant angle of the roadway 12 and (φL≠ φR) represents a variable angle of the roadway 12. Therefore, the following generally applies: If the difference between the measured and the lateral acceleration reaches or exceeds the threshold T, the RCE application 46 proceeds to block 410. However, if the difference between the estimated and the measured lateral acceleration does not exceed the threshold T, or if the ADAS functions are classified as inactive in block 404, the RCE application 46 proceeds to block 412, in which the RCE application 46 calculates the center angle of the steering wheel 16 without any adjustment based on a camber 64 or the angle of the road surface 12. Subsequently, in block 414, the RCE application 46 terminates. If, however, the difference between the measured and the lateral acceleration reaches or exceeds the threshold value T, system 10 and the RCE application 46 enter section 416 for calculating the steering angle correction, starting at block 410. During section 416 of the steering angle correction calculation, the RCE application 46 uses at least one of two different methods. In the first method, the RCE application 46 resets the previously learned value for the mean steering angle in block 420 and temporarily interrupts a learning phase for the angle correction. The learning phase for the angle correction is resumed when the ADAS functions are no longer active. In a second method, in block 422, the angle correction function of the RCE application 46 calculates the center angle of the steering wheel 16 based on the estimated angle of the camber 64 of the road surface 12. From block 422, the RCE application 46 proceeds to block 424, where it performs a final correction calculation of the steering wheel 16 angle. This final correction calculation uses an estimated angle of camber 64 of the road surface 12, the resulting center angle of the steering wheel 16, and a previously learned value as inputs. More precisely, in block 422, the RCE application 46 uses a calibration table that maps the estimated camber 64 of the road surface 12 to the center angle (δcenter) of the steering wheel 16, according to: It becomes clear that the value for the center angle (δcenter) of the steering wheel 16 can change more gradually at smaller angles of camber 64 of the road surface 12 and more aggressively at larger angles of camber 64 of the road surface 12, or vice versa, depending on the calibration of the system 10. Thus: where δcenter,learned is the previously learned center angle of the steering wheel 16 at a specific angle of camber 64 of the road surface 12 and δcenter,road is the estimated center angle of the steering wheel 16 resulting from the road surface 12. From block 424, the system 10 and the RCE application 46 transition to block 426. In block 426, the calculated center value δcenter of the steering wheel 16 is used in an ARS feature when the angle of the roadway 12 changes: In several aspects, the estimated camber 64 of the roadway 12 is implemented as the estimated resulting center angle of the steering wheel 16 of the roadway 12 as an equivalent value of the camber 64 of the roadway 12 via a calculation that compensates for the heading angle of the vehicle 14 in order to maintain straight-line motion of the vehicle 14 without driver intervention. Thus, the ARS application 52 compensates for the camber 64 of the roadway 12 by calculating the center angle of the steering wheel based on the estimated angle of the roadway 12. Subtracting the steering center angle resulting from the angle of the road surface 12 from the previously learned steering center angles yields a new center angle of the steering wheel 16 without influences from the road surface 12. The new center angle of the steering wheel 16 is then transmitted to the ARS application 52 so that it can be implemented by the steering actuators 23, etc., in the steering system. Figure 4, with further reference to Figures 1-3, illustrates an exemplary application of System 10 and RCE Application 46 in the form of a flowchart. The exemplary application begins in Block 500. Subsequently, in Block 502, System 10 and RCE Application 46 determine whether ADAS applications 44 are active. If it is determined that no ADAS applications 44 or functions are active, System 10 and RCE Application 46 proceed to Block 504. In Block 504, angle correction learning and compensation remain active and perform real-time learning. If, according to Block 502, System 10 and RCE Application 46 determine that ADAS applications 44 or functions are active, System 10 and RCE Application 46 proceed to Block 506. In block 506, system 10 and RCE application 46 temporarily interrupt the learning of the angle correction. In block 508, system 10 and RCE application 46 receive inputs from sensors 22, such as...Cameras 24, IMUs 26, and the like. The data from the sensors 22, including cameras 24, IMUs 26, and the like, are used as inputs in block 510 to perform real-time acquisition and estimation of the angle of the roadway 12. From each of blocks 506 and 510, the system 10 and the RCE application 46 proceed to block 512, where the system 10 and the RCE application 46 perform an angle correction compensation based on the previously learned center angle of the steering wheel 16 and the steering center angle resulting from the angle of the roadway 12. From blocks 504 and 512, system 10 and RCE application 46 finally move to block 514, where ARS application 46 is switched on to generate an output to one or more actuators 23 of the vehicle 14.In several aspects, the output to the one or more actuators 23 ensures that the steering wheel 16 returns to a correct center position without additional effort from the driver and without constant correction by the ADAS applications 52. Accordingly, using the system 10 and the RCE application 46, the steering angle calculations can be dynamically and proactively adjusted in real time when the angle of the road surface 12 or the camber 64 changes in direction or magnitude. This compensates for the effects of the road surface 12's topography on the outputs of the ARS application 52, resulting in a natural, reliable, and predictable steering feel in the vehicle 14 and preventing continuous push / pull or ping-pong movements while driving with the ADAS application 44. In several respects, the system 10 and the RCE application 46 can remain active while the vehicle 14 is in motion, and the processes shown and described in Figures 3 and 4 can be repeated automatically, continuously, periodically, or upon the occurrence of a specific event, such as the detection of deviations in the road surface 12's topography, as described above. A system 10 and an RCE application 46 of the present invention offer several advantages. These include the ability to use the steering sensors 23 and the force estimation of the rack 18 to evaluate the lateral forces on the roadway 12 caused by different angles of the roadway 12, including roadway camber, and subsequently to provide an estimate of the angle of the roadway 12. With this data, the system 10 and the RCE application 46 can temporarily suspend the use of previously learned values ​​for an ARS application 52 on a roadway 12 with a different apex angle than the current roadway 12, since these changes could worsen the steering angle due to the calculations of the steering center.Furthermore, the system 10 and the RCE application 46 take into account the angle of the road surface 12 and the resulting steering wheel angle 16, adjusting the inputs to the ARS application 52 accordingly to avoid push / pull conditions. By subtracting the estimated steering angle caused by the road surface 12 from the previously learned angle, the system 10 and the RCE application 46 ensure that the steering wheel 16 returns to the correct center position without requiring additional effort from the driver and / or without the ADAS application 44 making constant corrections. If the direction or magnitude of the angle of the road surface 12 changes, the steering angle calculation can be dynamically adjusted in real time to proactively compensate for the influence of the road surface 12 on the active feedback steering function.Furthermore, the system 10 and the RCE application 46 of the present invention can be implemented on existing hardware and retrofitted into existing vehicles 14, etc. The system 10 and the RCE application 46 offer improved redundancy, resilience, reliability, and responsiveness, and increase driver comfort without increasing the complexity of the system 10, while maintaining or reducing manufacturing complexity without compromising the efficiency and performance of the system 10. They also reduce the potential for undesired movements of the vehicle 14 within a lane or, more generally, across the surface of the roadway 12 when the topography of the roadway 12 changes. Figure labeling for Fig. 4: Y = Yes N = No

Claims

System (10) for improving the performance of an Advanced Driver Assistance System (ADAS) and Active Steering Feedback (ARS) by utilizing the estimated road camber (64), the system (10) comprising: a vehicle (14) with one or more sensors (22), wherein the one or more sensors (22) acquire static and dynamic information about the vehicle (14) and the vehicle's (14) environment; one or more actuators (23) of the vehicle (14), wherein the one or more actuators (23) modify the static and dynamic behavior of the vehicle (14); a steering wheel (16) of the vehicle (14), wherein the steering wheel (16) is connected to steerable wheels of the vehicle (14) via a rack (18) of the vehicle (14), and the steering wheel (16) is capable of changing the steering angle and trajectory of the vehicle (14) by means of the one or more actuators (23);a controller (34) of the vehicle (14), wherein the controller (34) has a processor (36), a memory (32) and input / output (I / O) ports, wherein the I / O ports of the controller (34) communicate with the one or more sensors (22) and the one or more actuators (23); wherein the processor (36) executes program code sections stored in the memory (32), wherein the program code sections receive information from the one or more sensors (22) via the I / O ports and transmit instructions via the I / O ports to the one or more actuators (23) to modify the static and dynamic behavior of the vehicle (14), wherein the program code sections include a road camber estimation (RCE) application comprising: a first control logic (402, 510) for performing the detection of the road camber angle of a road section on which the vehicle (14) is currently moving;a second control logic (416) which uses two methods (420, 422, 506, 512) of steering angle correction, namely a first method (420, 506) which temporarily pauses a learning phase for steering angle correction and uses a previously learned value for steering angle correction to return the steering wheel (16) to the center while ADAS takes precedence and avoids continuous correction by ADAS functions, and a second method (422, 512) which compensates for the effects of the road angle on lateral movement and calculations of the steering wheel torque feedback; a third control logic which uses an output from the second method (422, 512) of steering angle correction to calculate a steering angle correction; and a fourth control logic which compensates for changes in the road angle;by including the road angle in the calculations of the steering center angle, the active steering feedback (ARS) of the RCE application actively and in real time brings the steering wheel (16) into a precise center position, independent of the topography of the road section, which corresponds to the current trajectory of the vehicle (14) on the road section. System (10) according to claim 1, characterized in that the one or more sensors (22) further comprise: cameras (24) and inertial measurement units (IMUs) (26) that can measure movements and accelerations in at least three degrees of freedom; and the one or more actuators (23) comprise servo-assist actuators of the steering system (33) comprising at least one of the following elements: pumps for hydraulic power steering, electro-hydraulic power steering, pneumatic power steering and electro-pneumatic power steering, as well as electromechanical actuators (23) for electromechanical power steering, wherein the servo-assist actuators are able to influence at least one steering speed, one steering position and one steering angle via the rack (18). System (10) according to claim 1, characterized in that the first control logic further comprises: control logic that determines the activity status of the applications of the Lane Keeping Assist (LKA), the Lane Centering Control (LCC) and the ARS of the ADAS; and, if it is determined that the applications LKA, LCC and ARS are inactive, calculates a center angle for the steering without taking the road angle into account; and, if it is determined that the applications LKA, LCC and ARS are active, acquires static and dynamic vehicle information as well as environmental information from the one or more sensors (22); and acquires and estimates a current road angle from the static and dynamic information of the vehicle (14) and from the environmental information. System (10) according to claim 3, characterized in that the system (10) further comprises: control logic that estimates a lateral force acting on the vehicle (14) according to: F yf = ( LF r − F ztotal cos ( τ ) [ rkp cos ( γ ) + R nom . sin ( γ ) ] − T ztotal cos ( γ ) [ t cos ( τ ) + R nom . sin ( τ ) ] ) where T ztotal , F ztotal and N fx can be calculated as follows: T ztotal = F ztotal sin ( γ ) cos ( τ ) sin ( δ w ) [ cos ( τ ) ( rkp + R nom . sin ( τ ) ) ] F ztotal = N fx 2 + zg N fxay L fg , N fx = mg X rxr + xf − max Z gxr + xf , where L, F r , r kp , R nom , γ, τ are the length of the steering arm lever, the force of the rack (18), the offset of the steering axis relative to the wheel in the lateral direction, the nominal radius of the wheel, the kingpin angle or the camber angle. X f , X r are the wheelbase of the vehicle (14) from the center of gravity (CG) to the front or rear axle, m represents the unsprung mass of the vehicle (14) and Z G represents the height of the vehicle's center of gravity. System (10) according to claim 4, characterized in that the system (10) comprises: control logic that estimates: a lateral force on the rear axle based on the yaw motion calculated by an inertial measurement unit (IMU) of one or more sensors (22), and an external yaw moment due to torque vectoring devices as: I zr ˙ = TM + L 1 F yfcos ( δ f ) − L 2 F yr , and F yr = ( TM + L 1 F yf cos ( δ f ) − I zr ˙ ) / L 2 , so that the lateral acceleration of the vehicle (14) is estimated using an estimate of lateral forces in the front and rear axles according to: a ^ y = ( F yf + F yr cos ( δ r ) ) / M ; and Control logic, the estimated lateral acceleration – y with the lateral acceleration a measured by the IMU ymeas compares according to: a ^ y − aymeas = Δ ay ≥ T ; and , when it is determined that the difference Δa y between the estimated â y and the measured a ymeas If the lateral accelerations reach or exceed the threshold value T, it can be concluded that the vehicle (14) is subject to the road angle. System (10) according to claim 5, characterized in that the system (10) further comprises: control logic that calculates the contribution of the road angle to the lateral forces (F_(y, road)) according to: F y , road = { mg ( sin φ ) mg ( sin φ L − sin ( φ L − φ R ) = sin ( φ eqv ) ) = φ 〛 _ L = φ _ R ) for a constant road angle, and where (φ L ≠ φ R ) for a variable track angle, and in general: aymeas − a ^ y = mgsin ( φ eqv ) . System (10) according to claim 1, characterized in that the third control logic further comprises: control logic which calculates a steering wheel center angle by subtracting an estimated steering wheel angle δcenter,road resulting from the road surface from a previously learned steering wheel center angle δcenter,learned according to: δcenter(t) = δcenter,learned(t) − δcenter,road(t). where the values ​​of the steering wheel center angle δ center Change gradually for small road camber angles and change aggressively for large road camber angles. System (10) according to claim 7, characterized in that the fourth control logic further comprises: control logic which, upon detection of a change in road angle, uses the calculated value of the steering center angle δcenter in ARS adjustments for adjustments of the steering wheel center position. Method for improving the performance of an advanced driver assistance system (ADAS) and active steering feedback (ARS) by utilizing the estimated road camber (64), the method comprising: acquiring static and dynamic information about a vehicle (14) and about an environment of the vehicle (14) with one or more sensors of the vehicle (14); modifying the static and dynamic behavior of the vehicle (14), including changing the steering angle and trajectory of the vehicle (14) with one or more actuators (23) of the vehicle (14), wherein the one or more actuators (23) are connected to a steering wheel (16) of the vehicle (14) and a steering rack (18) of the vehicle (14), and the steering wheel (16) is connected via the steering rack (18) of the vehicle (14) to steerable wheels of the vehicle (14);Execution of program code sections stored in the memory (32) of a controller (34) of the vehicle (14), wherein the controller (34) further comprises a processor (36) and input / output (I / O) ports, wherein the I / O ports of the controller (34) are connected to the one or more sensors (22) and the one or more actuators (23);wherein the processor (36) executes program code sections stored in the memory (32), wherein the program code sections receive information from the one or more sensors (22) via the I / O ports and transmit instructions via the I / O ports to the one or more actuators (23) to modify the static and dynamic behavior of the vehicle (14), wherein the program code sections include a road camber estimation (RCE) application, with control logic for: performing the detection of the road angle of a road section on which the vehicle (14) is currently moving;Using two steering angle correction methods, namely a first method (420, 506) which temporarily pauses a learning phase for steering angle correction and uses a previously learned value for steering angle correction to return the steering wheel (16) to the center while ADAS takes precedence and avoids continuous correction by ADAS functions, and a second method (422, 512) which compensates for the effects of the road angle on lateral motion and calculations of the steering wheel torque feedback; calculating a steering angle correction from an output of the second steering angle correction method; and compensating for changes in the road angle;and incorporating the road angle into the calculations of the steering center angle to cause the active steering feedback (ARS) of the RCE application to actively and in real time move the steering wheel (16) to a precise center position that matches the current trajectory of the vehicle (14) on the road section, regardless of the topography of the road section.

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