Vehicle steering system with angular road surface compensation

Abstract

The steering system includes a controller in communication with the sensors. The controller is configured to determine a counter torque to apply to the steering system using a side slip and pull compensation system based on inputs to the steering wheel, apply the counter torque to the steering system, and determine an operating state of an advanced driver assistance system. The controller is further configured to determine an angle of a road surface based on the plurality of sensors when the advanced driver assistance system is activated, and apply an updated counter torque to the steering system when at least one of a magnitude or a direction of the angle of the road surface changes while the advanced driver assistance system is activated.

Description

Technical Field

[0001] This disclosure relates to steering systems for vehicles, and more particularly to steering systems that compensate for road camber. Background Technology

[0002] When operating a vehicle, the driver may need to compensate for external forces that can cause the vehicle to deviate from its path, such as road camber or wind. To assist the driver, a lateral and pull compensation (LPC) system applies corrective torque to the steering system, eliminating the need for the driver to apply force to the steering wheel to maintain the vehicle in a straight line. Summary of the Invention

[0003] A steering system is disclosed herein. The system includes a controller that communicates with sensors. The controller is configured to determine, based on input to the steering wheel using a yaw and pull compensation system, apply the counter-torque to the steering system, and determine the operating state of an advanced driver assistance system (ADAS). The controller is also configured to determine the angle of the road surface based on multiple sensors when the ADAS is activated, and to apply an updated counter-torque to the steering system when the ADAS is activated and at least one of the magnitude or direction of the road surface angle changes.

[0004] In one aspect of this disclosure, the angle of the road surface is determined based on various estimates of the angle of the road surface from the plurality of sensors.

[0005] In one aspect of this disclosure, each estimate of the road angle is weighted to produce a fused angle of the road surface.

[0006] In one aspect of this disclosure, various estimates of the angles of the road surface include angle estimation based on inertial measurement units, angle estimation based on maps, angle estimation based on cameras, and steering rack force angle estimation.

[0007] In one aspect of this disclosure, the controller is configured to determine the angle of the road surface based on performing cross error calculations on each of the various estimates of the angle of the road surface.

[0008] In one aspect of this disclosure, the updated counter-torque includes applying zero torque when an advanced driver assistance system is activated and at least one of the magnitude or direction of the road surface angle changes.

[0009] In one aspect of this disclosure, the plurality of sensors includes a front-facing camera module and an inertial measurement unit.

[0010] In one aspect of this disclosure, the controller is configured to determine the angle of the road surface based on high-definition map images.

[0011] In one aspect of this disclosure, the sensor includes at least one wheel speed sensor.

[0012] In one aspect of this disclosure, the steering system is a steer-by-wire system.

[0013] In one aspect of this disclosure, the controller is configured to determine the angle of the road surface based on a determined steering rack force.

[0014] This document discloses a method for operating a steering system on a vehicle. The method includes determining, based on input to the steering wheel on the vehicle, a yaw and pull compensation system to determine a counter-torque to be applied to the steering system, applying the counter-torque to the steering system on the vehicle, and determining the operating state of an advanced driver assistance system (ADAS) on the vehicle. The method further includes: determining, when the ADAS is activated, the angle of the road surface supporting the vehicle using multiple sensors on the vehicle; and applying an updated counter-torque to the steering system when the ADAS is activated and at least one of the magnitude or direction of the road surface angle changes.

[0015] In one aspect of this disclosure, the angle of the road surface is determined based on various estimates of the road angle from the plurality of sensors.

[0016] In one aspect of this disclosure, each estimate of the angle of the road surface is weighted to produce a fused angle of the road surface.

[0017] In one aspect of this disclosure, various estimates of the angles of the road surface include angle estimation based on inertial measurement units, angle estimation based on maps, angle estimation based on cameras, and steering rack force angle estimation.

[0018] In one aspect of this disclosure, determining the angle of the road surface supporting the vehicle includes performing a cross error calculation on each of the various estimates of the angle of the road surface.

[0019] In one aspect of this disclosure, the updated counter-torque includes applying zero torque when an advanced driver assistance system is activated and at least one of the magnitude or direction of the road surface angle changes.

[0020] In one aspect of this disclosure, the sensor includes a front-facing camera module and an inertial measurement unit.

[0021] A vehicle is disclosed herein. The vehicle includes a steering system and a controller, the steering system being configured to change the road angle relative to at least one of a plurality of wheels, the controller communicating with sensors and the steering system. The controller is configured to determine, apply the counter torque to the steering system based on input to the steering wheel using a yaw and pull compensation system, apply the counter torque to the steering system, and determine the operating state of an advanced driver assistance system. The controller is also configured to determine the angle of the road surface based on a plurality of sensors when the advanced driver assistance system is activated, and to apply an updated counter torque to the steering system when the advanced driver assistance system is activated and at least one of the magnitude or direction of the road surface angle changes.

[0022] In one aspect of this disclosure, the controller is configured to determine the angle of the road surface based on a determined steering rack force.

[0023] Option 1. A steering system, comprising:

[0024] Multiple sensors; and

[0025] A controller, which communicates with the plurality of sensors, wherein the controller is configured to:

[0026] Based on the input to the steering wheel, the sideslip and pull compensation system is used to determine the counter torque to be applied to the steering system;

[0027] Apply counter-torque to the steering system;

[0028] Determine the operational status of the advanced driver assistance system;

[0029] When the advanced driver assistance system is activated, the angle of the road surface is determined based on multiple sensors; and

[0030] When the advanced driver assistance system is activated and at least one of the angles or directions of the road surface changes, an updated counter-torque is applied to the steering system.

[0031] Option 2. The steering system according to Option 1, wherein the angle of the road surface is determined based on various estimates of the angle of the road surface from the plurality of sensors.

[0032] Option 3. The steering system according to Option 2, wherein each estimate of the angle of the road surface is weighted to produce a fused angle of the road surface.

[0033] Option 4. The steering system according to Option 3, wherein the various estimates of the road surface angle include angle estimation based on inertial measurement unit, angle estimation based on map, angle estimation based on camera, and steering rack force angle estimation.

[0034] Option 5. The steering system according to Option 2, wherein the controller is configured to determine the angle of the road surface based on performing a cross error calculation on each of the various estimates of the angle of the road surface.

[0035] Option 6. The steering system according to Option 1, wherein the updated counter torque includes applying zero torque when the advanced driver assistance system is activated and at least one of the magnitude or direction of the road surface angle changes.

[0036] Option 7. The steering system according to Option 1, wherein the plurality of sensors include a front camera module and an inertial measurement unit.

[0037] Option 8. The steering system according to Option 7, wherein the controller is configured to determine the angle of the road surface based on a high-definition map image.

[0038] Option 9. The steering system according to Option 8, wherein the plurality of sensors includes at least one wheel speed sensor.

[0039] Option 10. The steering system according to Option 1, wherein the steering system is a steer-by-wire system.

[0040] Option 11. The steering system according to Option 1, wherein the controller is configured to determine the angle of the road surface based on a determined steering rack force.

[0041] Option 12. A method for operating a steering system on a vehicle, the method comprising:

[0042] Based on the input from the steering wheel on the vehicle, a lateral and pull compensation system is used to determine the counter torque to be applied to the steering system;

[0043] Apply counter-torque to the vehicle's steering system;

[0044] Determine the operational status of the advanced driver assistance systems on the vehicle;

[0045] When the advanced driver assistance system is activated, multiple sensors on the vehicle are used to determine the angle of the road surface supporting the vehicle; and

[0046] When the advanced driver assistance system is activated, and at least one of the angles or directions of the road surface changes, an updated counter-torque is applied to the steering system.

[0047] Option 13. The method according to Option 12, wherein the angle of the road surface is determined based on various estimates of the angle of the road surface from the plurality of sensors.

[0048] Option 14. The method according to Option 13, wherein each estimate of the angle of the road surface is weighted to produce a fused angle of the road surface.

[0049] Option 15. The method according to Option 14, wherein the various estimates of the angle of the road surface include angle estimation based on inertial measurement unit, angle estimation based on map, angle estimation based on camera, and steering rack force angle estimation.

[0050] Option 16. The method according to Option 13, wherein determining the angle of the road surface supporting the vehicle includes performing a cross error calculation on each of the various estimates of the angle of the road surface.

[0051] Option 17. The method according to Option 12, wherein the updated counter torque includes applying zero torque when the advanced driver assistance system is activated and at least one of the magnitude or direction of the road surface angle changes.

[0052] Option 18. The method according to Option 12, wherein the plurality of sensors includes a front-facing camera module and an inertial measurement unit.

[0053] Option 19. A vehicle comprising:

[0054] A steering system configured to change the road angle relative to at least one of a plurality of wheels;

[0055] Multiple sensors; and

[0056] A controller, which communicates with the plurality of sensors and the steering system, is configured to:

[0057] Based on the input from the steering wheel on the vehicle, a lateral and pull compensation system is used to determine the counter torque to be applied to the steering system;

[0058] Apply counter-torque to the steering system;

[0059] Determine the operational status of the advanced driver assistance systems on the vehicle;

[0060] When the advanced driver assistance system is activated, it determines the angle of the road surface supporting the vehicle based on multiple sensors on the vehicle; and

[0061] When the advanced driver assistance system is activated and at least one of the angles or directions of the road surface changes, an updated counter-torque is applied to the steering system.

[0062] Option 20. The vehicle according to Option 19, wherein the controller is configured to determine the angle of the road surface based on a determined steering rack force. Attached Figure Description

[0063] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the specification, explain the principles of the present disclosure.

[0064] Figure 1A This is a functional block diagram of an example hydraulic power steering (HPS) system according to the present disclosure, including a controller with a torque steering mitigation module and a road angle detection module.

[0065] Figure 1B This is a functional block diagram of an example electronic power steering (EPS) system according to the present disclosure, including a controller with a torque steering mitigation module and a road angle detection module.

[0066] Figure 1C This is a functional block diagram of an example of a steer-by-wire (SBW) system according to the present disclosure, including a controller with a torque steering mitigation module and a road angle detection module.

[0067] Figure 2 The illustration shows an example of a vehicle traveling on a flat or angled road with a non-zero road angle.

[0068] Figure 3 This is a flowchart illustrating an example of a method for performing lateral and tension compensation on a cambered road surface.

[0069] Figure 4 This is a flowchart of the method for detecting and judging the camber angle.

[0070] In the accompanying drawings, reference numerals may be used repeatedly to identify similar and / or identical elements. Detailed Implementation

[0071] Vehicles can operate on roads with road angles (convex surfaces, angled surfaces, sloping surfaces, or cambered surfaces) to improve drainage and prevent water from accumulating on the road surface. When roads are flat or concave, water can accumulate on the road surface and may cause vehicles to skid on water and / or cause road damage. While angled roads reduce drainage-related problems, they introduce additional lateral forces on the vehicle due to its tilted mass.

[0072] While a vehicle is operating on the road, the driver may need to apply a constant force to the steering wheel to maintain the vehicle's straight-line travel. To assist the driver, the vehicle can utilize a yaw and pull compensation (LPC) system to alleviate the need for the driver to apply a constant force to the steering wheel. For example, the LPC system uses information from sensors throughout the vehicle to detect when the vehicle is constantly pulled to one side or requires constant steering input to maintain a straight path. The LPC system uses a learning function to determine the counter-torque applied through the steering system to help maintain the vehicle along the straight path. However, when the vehicle activates features from advanced driver assistance systems (ADAS) that are separate from the LPC system (such as manual lane centering assist (HoLCA) or lane keeping assist (LKA)), the LPC system no longer performs active learning because it does not integrate ADAS overlap data.

[0073] When ADAS is activated, the pause in active learning for the LPC system presents a challenge when the direction (such as left or right) or size of the road crown changes. This change can occur, in particular, when the vehicle transitions from operating on the right side of the road crown to operating on the left side, or vice versa. When ADAS is activated, the pause in learning may prevent the LPC system from learning new counter-torque to apply. Therefore, previously determined counter-torque may not effectively eliminate the need to apply constant steering input. One feature of this disclosure is that it allows the LPC system to apply updated counter-torque when ADAS is activated. In one example, the vehicle utilizes one or more sensors, a high-definition (HD) map, and / or rack force estimation to assess the lateral road forces caused by the changing road angle.

[0074] Now for reference Figures 1A to 1C Examples of hydraulic, electronic, and steer-by-wire power steering systems that can be incorporated into vehicle 10 are shown. While examples of these power steering systems are shown, this disclosure is applicable to other power steering systems as well. Figure 1A In this configuration, the steering mechanism 36 is a rack and pinion type system, comprising a toothed rack (not shown) and a pinion (also not shown) located within rack and pinion housings 50 and 52. When the driver turns the steering wheel 26, the steering shaft 29 rotates the lower steering shaft 51, which is connected to the steering shaft 29 via a universal joint 34. The lower steering shaft 51 rotates the pinion. The rotation of the pinion moves the rack, which in turn moves a link 38 connected to the steering knuckle 39 and the wheel 42 (one side shown).

[0075] The hydraulic power steering system includes an actuator 60 that controls a pump 56 that pumps hydraulic fluid from a reservoir 58. The actuator 60 is connected to a variable assist actuator 64 via a hydraulic line 62. A hydraulic line 66 connects the variable assist actuator 64 back to the reservoir 58. The variable assist actuator 64 provides a variable hydraulic assist torque. Generally, the vehicle engine (not shown) rotates the pump 56. In response to a control signal on line 54, the actuator 60 selectively valves pressurized fluid from the pump 56 to the hydraulic line 62, selectively controlling the hydraulic assist torque provided by the system. The hydraulic line 62 inputs to the hydraulic assist actuator 64, which provides hydraulic power assistance to the steering system via a lower steering shaft 51. Hydraulic fluid output from the hydraulic assist actuator 64 returns to the reservoir 58 via the hydraulic line 66.

[0076] In some examples, vehicle speed signal 14 is input to controller 16, and sensor 21 provides controller 16 with steering wheel position signal and / or steering wheel torque signal. Controller 16 also uses steering wheel speed information, which it can determine by integrating the steering wheel position signal. In some examples, in addition to a torque sensor, sensor 21 may include an optically encoded type sensor, a variable resistance type sensor, or another suitable type of position sensor.

[0077] During operation, when the driver drives the vehicle and turns the steering wheel, the controller 16 senses the vehicle speed, steering wheel position, steering wheel torque, and / or steering wheel speed. The controller 16 generates commands for the actuator 60. By controlling the flow rate of hydraulic fluid through the actuator 60 to the hydraulic line 62, the controller 16 indirectly controls the pump 56, which automatically turns on or off in response to fluid pressure in the reservoir 58. The controller 16 controls the actuator 60 such that, during normal driving conditions, a relatively constant low flow rate of hydraulic fluid is supplied to the hydraulic auxiliary actuator 64 through the hydraulic line 62. In response to high steering wheel speed or lateral acceleration maneuvers, the flow rate of hydraulic fluid to the actuator 64 increases.

[0078] In one example, controller 16 includes a yaw and pull compensation module 84, which estimates and compensates for steering wheel feedback torque. This compensated steering wheel feedback torque is output to a hydraulic power steering module 82, which adjusts the operation of the steering system. A road angle detection module 86, further described below, detects when the vehicle is driving at a road angle and / or provides road angle torque feedback to the hydraulic power steering module 82.

[0079] exist Figure 1BIn this configuration, the input of the electric power steering (EPS) motor 90 is connected to the steering shaft 29. The output of the EPS motor 90 is connected to the steering shaft 91, which drives the pinion gear. The EPS motor 90 responds to the EPS module 88, the yaw and pull compensation module 84, and the road angle detection module 86 to vary the torque assistance, as will be further described below.

[0080] exist Figure 1C In this configuration, the angular position and torque of the steering wheel 26 are sensed by sensor 110. Steering wheel motor 112 is configured to provide steering feedback to steering wheel 26 to provide road feel. Controller 16 is configured to control road wheel angle (RWA) motor 118, which is configured to adjust the wheel angle. Steering wheel motor 112 responds to steer-by-wire (SBW) module 114, yaw and pull compensation module 84, and road angle detection module 86 to vary torque assistance, as will be further described below. The output of RWA motor 118 is connected via steering shaft 120, which drives a pinion gear.

[0081] like Figure 2 As shown, when vehicle 10 is on the right curb RC of the road, the LPC system learns to apply a first torque T1 to the steering wheel 11 to keep vehicle 10 in a straight line. When vehicle 10 transitions to the left curb LC of the road with the ADAS system activated, the learning of the LPC system is disabled. Therefore, if vehicle 10 continues to maintain the first torque T1 used to keep vehicle 10 in a straight direction while traveling on the right curb RC, vehicle 10 will move closer to the left edge of the road surface. The ADAS system then applies a second torque T2 to keep or assist vehicle 10 on the road surface. One feature of this disclosure relates to updating the torque applied by the LPC system when the ADAS is activated and the road surface of the vehicle includes a change in size or orientation (e.g., from the left curb to the right curb).

[0082] Figure 3 The illustration shows a flowchart of an example method 200 for performing lateral and pull compensation when changing lanes along a road surface (such as a cambered road surface). Method 200 includes a first part 202 for performing road angle detection, a second part 204 for selecting a lateral and pull compensation strategy, a third part 206 for performing steering wheel torque calculation, and a fourth part 208 for performing lateral and pull compensation calculations.

[0083] In the first part 202 of method 200, method 200 begins at box 210 (“Start”). Method 200 then proceeds to box 212. At box 212 (“ADAS feature activated?”), method 200 determines whether advanced driver assistance system (ADAS) features on the vehicle, such as manual lane centering assist (HoLCA) and lane keeping assist (LKA), are activated. If the ADAS features are not activated, the method proceeds to box 214.

[0084] At box 214 (“LPC Torque Calculation (No Adjustment)”), method 200 performs LPC torque calculation without adjusting for camber angle, and then proceeds to box 216 (“End”), and method 200 ends.

[0085] If it is determined that the ADAS feature is activated at box 212, method 200 proceeds to box 220. At box 220 (“Road Camber Angle Detection and Judgment”), method 200 uses multiple inputs from box 218 (“Input”) to detect the road camber angle. Figure 4 The camber angle detection and determination performed at box 220 is shown in more detail.

[0086] like Figure 4 As shown, the input from box 218 may include at least one of the following: an image from the front camera module (FCM) 302, a high-definition (HD) map 304, inertial measurement unit (IMU) data from IMU 306, wheel speed sensor (WSS) data from WSS 308, or steering rack force 310. These inputs are fed into box 220 to determine various estimates of the road surface angle. Using the input from box 218, method 200 may perform an IMU-based camber angle estimation to produce an IMU-based camber angle estimate θ at box 312. IMU Using the input from box 218, method 200 also performs map-based camber angle estimation to produce a map-based camber angle estimate θ at box 314. Map Using the input from box 218, method 200 also performs camera-based camber angle estimation to produce a camera-based camber angle estimate θ at box 316. Cam .

[0087] Method 200 also performs road camber angle estimation based on steering rack force at box 318 to produce a road camber angle estimate θ based on steering rack force. Rack In the first step of box 318, the road angle detection module 86 detects the road angle. In some examples, to eliminate or reduce the influence of the road angle on the lateral force estimation, the lateral force estimation is based on the rack force F in the front axle. yf :

[0088]

[0089] in, and N fx The following can be calculated:

[0090]

[0091] In the above equation, L is the steering arm lever, and F r It is rack force, r kp R is the offset of the steering axis from the tire in the lateral direction. nom X is the nominal tire radius, γ is the kingpin inclination angle, and τ is the camber angle. f and X r These are the wheelbase distances from the center of gravity (CG) to the front and rear axles, respectively. m represents the vehicle's unsprung mass, and Z represents the wheelbase distance. g This indicates the height of the vehicle's center of gravity (CG). g represents the gravitational coefficient. ax and ay represent the longitudinal and lateral accelerations, respectively. δ f It refers to the front tire steering angle. L f It is the width of the front axle track. It is the total resistance torque generated around the steering z-axis. It is the total resistance generated around the steering z-axis. N fx This is normal tire pressure.

[0092] In some examples, the lateral force in the vehicle's rear axle is based on the yaw motion I calculated from the IMU 70. z r is estimated using the external yaw moment caused by the torque vectorization device:

[0093] I z r·=T M +L1F yf cos(δ f )-L2F yr ;as well as

[0094]

[0095] Where T M It is the traction force, L1 is the length of the front axle, F yf L1 is the front lateral tire force, L2 is the rear axle length, and F is the rear wheel axle length. yr It is the rear lateral tire force, I z is the vehicle's yaw moment, and r is the vehicle's yaw angular velocity.

[0096] Lateral acceleration can be estimated by using the estimation of lateral forces in the front and rear axles. as follows:

[0097]

[0098] The following compares the lateral acceleration with the lateral acceleration measured by the IMU 70: If the acceleration is estimated and measured lateral acceleration If the difference exceeds a predetermined threshold T, then the influence of the road angle on the vehicle can be determined. The contribution of the road angle to the lateral force is calculated as follows:

[0099]

[0100] Therefore, generally

[0101] Using the camber angle estimation described above, method 200 proceeds to box 320. At box 320 (“Cross Error Calculation”), the cross error calculation for the camber angle estimation is performed as follows:

[0102]

[0103] Method 200 then proceeds to box 322. At box 322 (“Adjusting weights based on relevant error”), method 200 adjusts each weight in the camber angle estimation as follows:

[0104] [w1,w2,w3,w4]=f([E])

[0105] Method 200 then proceeds to box 324. At box 324 (“Update Fusion”), method 200 generates a fused camber angle θ based on the weights from each of the camber angle estimates. f ,as follows:

[0106] θ f =w1θ IMU +w2θ Cam +w3θ Map +w4θ Rack

[0107] Using the calculated camber angle as shown above, method 200 determines whether a camber angle has been detected. If no camber angle is detected at box 220, method 200 proceeds to box 214 to perform the LPC torque calculation without adjustment before proceeding to box 216 and ending.

[0108] If a road camber angle is detected from box 220, the method proceeds to box 222. At box 222 (“OR”), method 200 can select between two different strategies for correcting the LPC. In the first strategy (“LPC torque = 0”) at box 224, the torque applied by the LPC is reset to zero. This allows the vehicle driver to compensate for roll / pull conditions until the ADAS feature is no longer activated.

[0109] In the second approach (“LPC Adjustment?”) at box 226, method 200 calculates the compensating steering torque to be applied. The compensating steering torque is corrected for the direction (such as left or right camber) and magnitude of the camber angle on the new road segment. To determine the compensating steering torque to be applied, method 200 proceeds to box 228.

[0110] At box 228 (“Torque Calculation”), method 200 determines the compensating steering wheel torque to be applied for the new road section. In one example, method 200 determines the compensating steering wheel torque by utilizing a calibration table. The calibration table includes predetermined steering wheel torques to be applied for different combinations of camber direction and size for camber angles, as follows:

[0111]

[0112] Where T steering wheel feedback It is for a given road camber direction and size. The applied steering wheel torque.

[0113] Depending on how the system is calibrated, torque feedback can be applied more gradually at smaller camber angles below a predetermined threshold and more aggressively at larger camber angles above a predetermined threshold, and vice versa. Therefore,

[0114] T steering,non-crown angle (t)=T LPC,learning (t)-T steering wheel feedback (t)

[0115] Where T LPC It is the feedback torque previously learned at a certain angle on the cambered road, and T steering wheel feedback This is the estimated road-synthetic steering torque. Method 200 can then proceed to box 230.

[0116] At box 230 (“LPC Calculation”), method 200 performs the LPC calculation. The calculated steering wheel torque feedback, T, is then applied in the event of a change in road angle. steering wheel feedback Used for LPC operations, as follows:

[0117]

[0118] Method 200 then adjusts the LPC torque output to T steeringwheel correction,total (t) and proceed to box 216 and end.

[0119] The foregoing description is illustrative in nature and is in no way intended to limit this disclosure, its application, or use. The broad teachings of this disclosure can be implemented in various forms. Therefore, while this disclosure includes specific examples, its true scope should not be so limited, as other modifications will become apparent upon examination of the drawings, specification, and appended claims. It should be understood that one or more steps within a method may be performed in a different order (or simultaneously) without altering the principles of this disclosure. Furthermore, while each of the embodiments described above is described as having certain features, any one or more of those features described with reference to any embodiment of this disclosure may be implemented in and / or combined with features of any other embodiment, even if such combinations are not explicitly described. In other words, the described embodiments are not mutually exclusive, and substitutions of one or more embodiments for each other remain within the scope of this disclosure.

[0120] Various terms are used to describe spatial and functional relationships between elements (e.g., between modules, circuit elements, semiconductor layers, etc.), including “connected,” “joined,” “linked,” “adjacent,” “next to,” “on top,” “above,” “below,” and “set.” Unless explicitly described as “direct,” when describing the relationship between first and second elements in the above disclosure, the relationship can be a direct relationship in which no other intermediate elements exist between the first and second elements, or an indirect relationship in which one or more intermediate elements exist between the first and second elements (spatially or functionally). As used herein, the phrase “at least one of A, B, and C” should be interpreted as meaning logic using the non-exclusive logic “OR” (A or B or C) and should not be interpreted as meaning “at least one of A, at least one of B, and at least one of C.”

[0121] In a diagram, the direction of the arrows typically indicates the flow of information (e.g., data or instructions) of interest. For example, when components A and B exchange various types of information, but the information transmitted from component A to component B is relevant to the diagram, the arrow may point from component A to component B. This unidirectional arrow does not imply that no other information is transmitted from component B to component A. Furthermore, for information sent from component A to component B, component B may send a request for the information or an acknowledgment of receipt of the information to component A.

[0122] In this application, including the following definitions, the term "module" or "controller" may be replaced by the term "circuit". The term "module" may refer to, be part of, or include the following: application-specific integrated circuit (ASIC); digital, analog, or mixed-signal analog / digital discrete circuit; digital, analog, or mixed-signal analog / digital integrated circuit; combinational logic circuit; field-programmable gate array (FPGA); processor circuitry (shared, dedicated, or grouped) that executes code; memory circuitry (shared, dedicated, or grouped) that stores code executed by the processor circuitry; other suitable hardware components that provide the aforementioned functionality; or some or all of the above, such as in a system-on-a-chip.

[0123] A module may include one or more interface circuits. In some examples, the interface circuits may include wired or wireless interfaces connected to a local area network (LAN), the Internet, a wide area network (WAN), or a combination thereof. The functionality of any given module disclosed herein may be distributed across multiple modules connected via the interface circuits. For example, multiple modules may allow for load balancing. In another example, a server (also referred to as a remote or cloud) module may perform some functions on behalf of a client module.

[0124] As used above, the term "code" can include software, firmware, and / or microcode, and can refer to programs, routines, functions, classes, data structures, and / or objects. The term "shared processor circuitry" covers a single processor circuitry that executes some or all of the code from multiple modules. The term "group processor circuitry" covers a processor circuitry that, in combination with additional processor circuitry, executes some or all of the code from one or more modules. References to multiple processor circuitry cover multiple processor circuitry on discrete dies, multiple processor circuitry on a single die, multiple cores of a single processor circuitry, multiple threads of a single processor circuitry, or a combination thereof. The term "shared memory circuitry" covers a single memory circuitry that stores some or all of the code from multiple modules. The term "group memory circuitry" covers a memory circuitry that, in combination with additional memory, stores some or all of the code from one or more modules.

[0125] The term "memory circuit" is a subset of the term "computer-readable medium." As used herein, the term "computer-readable medium" does not cover transient electrical or electromagnetic signals propagating through a medium (e.g., on a carrier wave); the term "computer-readable medium" can therefore be considered tangible and non-transient. Non-limiting examples of non-transient tangible computer-readable media are non-volatile memory circuits (e.g., flash memory circuits, erasable programmable read-only memory circuits, or masked read-only memory circuits), volatile memory circuits (e.g., static random access memory circuits or dynamic random access memory circuits), magnetic storage media (e.g., analog or digital magnetic tape or hard disk drives), and optical storage media (e.g., CDs, DVDs, or Blu-ray discs).

[0126] The apparatus and methods described in this application can be implemented, in part or in whole, by a special-purpose computer created by configuring a general-purpose computer to perform one or more specific functions implemented in a computer program. The aforementioned function blocks, flowchart components, and other elements serve as software specifications that can be routinely converted into computer programs by skilled technicians or programmers.

[0127] A computer program includes processor-executable instructions stored on at least one non-transitory tangible computer-readable medium. A computer program may also include or depend on stored data. A computer program may encompass a basic input / output system (BIOS) for interacting with the hardware of a special-purpose computer, device drivers for interacting with specific devices of the special-purpose computer, one or more operating systems, user applications, background services, background applications, etc.

[0128] Computer programs may include: (i) descriptive text to be parsed, such as HTML (Hypertext Markup Language), XML (Extensible Markup Language), or JSON (JavaScript Object Symbolization); (ii) assembly code; (iii) object code generated from source code by a compiler; (iv) source code executed by an interpreter; (v) source code compiled and executed by a just-in-time (JIT) compiler; and so on. As an example only, programs from languages ​​including C, C++, C#, Objective-C, Swift, Haskell, Go, SQL, R, and Lisp can be used. Fortran, Perl, Pascal, Curl, OCaml, HTML5 (Hypertext Markup Language, 5th Revision), Ada, ASP (Active Server Pages), PHP (PHP: Hypertext Preprocessor), Scala, Eiffel, Smalltalk, Erlang, Ruby, Lua, MATLAB, SIMULINK and Use the syntax of the language to write source code.

Claims

1. A steering system, comprising: Multiple sensors; as well as A controller, which communicates with the plurality of sensors, wherein the controller is configured to: Based on the input to the steering wheel, the sideslip and pull compensation system is used to determine the counter torque to be applied to the steering system; Apply counter-torque to the steering system; Determine the operational status of the advanced driver assistance system; When the advanced driver assistance system is activated, the angle of the road surface is determined based on multiple sensors; as well as When the advanced driver assistance system is activated and at least one of the angles or directions of the road surface changes, an updated counter-torque is applied to the steering system.

2. The steering system according to claim 1, wherein, The angle of the road surface is determined based on various estimates of the angle of the road surface from the multiple sensors.

3. The steering system according to claim 2, wherein, Each estimate of the angle of the road surface is weighted to produce a fused angle of the road surface.

4. The steering system according to claim 3, wherein, The various estimates of the road surface angles include angle estimation based on inertial measurement units, angle estimation based on maps, angle estimation based on cameras, and angle estimation based on steering rack force.

5. The steering system according to claim 2, wherein, The controller is configured to determine the angle of the road surface based on each of the various estimates of the angle of the road surface by performing cross error calculation.

6. The steering system according to claim 1, wherein, The updated counter-torque includes applying zero torque when the advanced driver assistance system is activated and at least one of the magnitude or direction of the road surface angle changes.

7. The steering system according to claim 1, wherein, The multiple sensors include a front-facing camera module and an inertial measurement unit.

8. The steering system according to claim 7, wherein, The controller is configured to determine the angle of the road surface based on high-definition map images.

9. The steering system according to claim 8, wherein, The plurality of sensors includes at least one wheel speed sensor.

10. The steering system according to claim 1, wherein, The steering system is a steer-by-wire system.

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