Systems and methods for increasing the available range of hitch angle estimates

Abstract

A system, method, and apparatus are provided in a vehicle having an HAA calculation system for estimating the articulation angle (HAA) of the attachment device between the vehicle and the towed trailer. The method includes: receiving multiple USS distance measurements from a first ultrasonic sensor (USS) on the vehicle when the vehicle is towing the trailer in a forward direction; receiving multiple HAA values ​​calculated using geometric equations or kinematic models corresponding to the multiple USS distance measurements; receiving USS distance measurements from the first USS when the vehicle is traveling in a reverse direction or experiencing a high HAA, but not receiving USS distance measurements from a second USS; estimating the HAA values ​​from the USS distance measurements by applying USS curve characteristics of the first USS; and providing the estimated HAA values ​​to a vehicle motion control system for controlling the movement of the vehicle and the trailer.

Description

Technical Field

[0001] The technical field generally relates to systems, methods, and apparatus for estimating the articulation angle (HAA) of a hitch, and more specifically to systems, methods, and apparatus for estimating the articulation angle (HAA) of a hitch using an ultrasonic sensor (USS) during various traction dynamic events of a traction operation in traction applications of motor vehicles. Background Technology

[0002] Autonomous, semi-autonomous, and conventional vehicles can be designed to tow or tether trailers with various front ends to accommodate a wide range of loads, including but not limited to flatbed trailers, enclosed trailers, cargo beds, campervans, boats, and sometimes other motor vehicles. Furthermore, a variety of different trailer hitches are used in towing operations, such as gooseneck hitches, weight-distribution hitches, pivot hitches, receiver hitches, and fifth-wheel hitches. Each configuration of trailer type and hitch type exhibits different vehicle dynamics. While limited, there are systems and devices that can enhance vehicle and trailer stability during towing operations; however, given the many combinations of trailers and hitches, there is no single solution that fits all problems, or even, for that matter, a solution that encompasses most or almost all potential combinations of vehicles, trailers, and hitches in connected operations. In addition, to improve the stability of these various connected combinations, manufacturers have introduced basic add-ons such as vehicle interior trim and wind deflectors (e.g., ground effect), which provide additional aerodynamic stability to the vehicle. In addition, a traction control system and an automatic adjustable suspension system were developed, which can proportionally change the vehicle height according to the load weight. The vehicle traction system still needs improvement in many aspects.

[0003] Ultrasonic sensors (USS) have traditionally been used as parking assistance features on vehicles. When towing a trailer, an array of ultrasonic sensors (USS) can be used to estimate the hitch articulation angle (HAA). However, the implementation of USS is limited, partly due to practical obstacles such as high levels of interference in signal reception noise, unwanted reflections in addition to those from the front of the trailer, such as reflections at the hitch point, and uncertain trailer shape.

[0004] Therefore, there is a need for improved methods, systems, and apparatus for USS to estimate the hinge angle (HAA) of the attachment device. Furthermore, other desirable features and characteristics of this disclosure will become apparent from the following detailed description and appended claims, in conjunction with the accompanying drawings and the foregoing technical and background information.

[0005] The information disclosed in this introduction is intended only to enhance the understanding of the background of this disclosure, and therefore may contain information that does not constitute prior art known to a person skilled in the art in this country. Summary of the Invention

[0006] This document discloses vehicle methods and systems, as well as related control logic for vehicle systems, methods for manufacturing such systems, methods for operating such systems, and motor vehicles equipped with onboard control systems. By way of example and not limitation, various embodiments for automatically determining the hinge angle of a trailer hitch for towing in a motor vehicle, and methods for automatically determining the hinge angle of a trailer hitch for towing in a motor vehicle, are presented.

[0007] In one embodiment, a HAA calculation system is provided in a vehicle for estimating the articulation angle (HAA) of a hitch between the vehicle and a towed trailer. The HAA calculation system includes a controller. The controller is configured to: receive multiple USS distance measurements from a first ultrasonic sensor (USS) on the vehicle when the vehicle is towing the trailer in a forward direction, wherein the USS distance measurement for a particular USS provides a distance measurement between the front of the particular USS and the towed trailer in a particular situation; receive multiple HAA values ​​calculated using geometric equations or kinematic models corresponding to the multiple USS distance measurements, wherein each HAA value corresponds to one of the multiple USS distance measurements, and each USS distance measurement has a corresponding HAA value; and determine the USS curve characteristics of the first USS. The USS curve features include: a curve fitting function (e.g., a polynomial) mapped to a possible valid cluster of multiple USS distance measurements of the first USS, defining a mathematical relationship between the USS distance measurements in the valid clusters of USS distance measurements and their corresponding HAA values; an upper bound function mapped to the upper boundary of the USS distance measurements in the valid clusters; and a lower bound function mapped to the lower boundary of the USS distance measurements in the valid clusters. The controller is also configured to receive USS distance measurements from the first USS when the vehicle is traveling in the reverse direction or experiencing a high HAA, but not from the second USS, which is used in pairs with the first USS distance measurements to calculate the HAA using geometric equations or kinematic models; to estimate HAA values ​​from the USS distance measurements from the first USS by applying the USS curve features of the first USS; and to provide the estimated HAA values ​​to a vehicle motion control system (e.g., trailer reversing assist) for controlling vehicle and trailer motion.

[0008] In some embodiments, a high HAA is an angle at which an accurate USS return cannot be obtained from either of the two USSs in any pair of USSs on the vehicle, which is used to calculate the HAA using geometric equations or kinematic models, but at which an accurate USS return can be obtained from one of the USSs in a pair of USSs.

[0009] In one embodiment, in order to determine the USS curve characteristics of the first USS, the controller is configured to: pair the USS distance measurement of the first USS with the corresponding HAA value to form a USS distance measurement / HAA value (USS-HAA) pair; perform cluster analysis on the USS-HAA pair; identify possible valid clusters of multiple USS distance measurements based on the cluster analysis; and determine a curve fitting function, an upper bound function, and a lower bound function from the possible valid clusters of multiple USS distance measurements.

[0010] In one embodiment, in order to estimate the HAA value from the USS distance measurement from the first USS by applying the USS curve characteristics of the first USS, the controller is configured to filter out the USS distance measurement of the first USS using an upper bound function and a lower bound function.

[0011] In one embodiment, in order to estimate the HAA value from the USS distance measurement from the first USS by applying the USS curve features of the first USS, the controller is further configured to match the USS distance measurement from the first USS with the estimated HAA based on the mathematical relationship between the USS distance measurement in the effective clusters where the USS distance measurement is applied and the corresponding HAA value defined by the curve fitting function.

[0012] In one embodiment, the controller is further configured to: receive multiple USS distance measurements for each of a plurality of USSs on the vehicle while the vehicle is towing a trailer in a forward direction; and determine a USS curve feature for each of the plurality of USSs within the range of the received USS distance measurements. The USS curve feature is extended beyond the range in which the USS curve feature was initially constructed to provide the expected range of an acceptable USS-HAA pair extending beyond the range of the received USS distance measurements.

[0013] In one embodiment, the controller is further configured to: receive a USS distance measurement from any one of the plurality of USSs when the vehicle is traveling in the opposite direction or experiencing a high HAA, but not receive a USS distance measurement from a second USS, the USS distance measurement from the second USS being used in pairs with a USS distance measurement from one of the plurality of USSs to calculate the HAA using geometric equations or a kinematic model; and estimate the HAA value from the USS distance measurement from one of the plurality of USSs by applying a USS curve feature from one of the plurality of USSs.

[0014] In one embodiment, when the vehicle is experiencing a high HAA, the controller is configured to: estimate the HAA value using appropriate USS curve characteristics; determine whether a HAA value calculated using geometric equations or a kinematic model is available; when a HAA value calculated using geometric equations or a kinematic model is available, select that HAA value to pass to the vehicle motion control; and when a HAA value calculated using geometric equations or a kinematic model is not available, select the estimated HAA value to pass to the vehicle motion control.

[0015] In another embodiment, a vehicle is provided having a HAA calculation system for estimating the articulation angle (HAA) of the attachment device between the vehicle and the towed trailer. The vehicle includes a plurality of ultrasonic sensors (USS) mounted on the vehicle to sense the distance between the sensors and the front of the towed trailer; a vehicle motion control system for controlling the movement of the vehicle and the trailer; and a controller. The controller is configured to: receive multiple ultrasonic sensor (USS) distance measurements of a first USS among the plurality of USS when the vehicle tows the trailer in a forward direction, wherein the USS distance measurement of a particular USS provides a distance measurement between the particular USS and the front of the towed trailer under a particular condition; receive a plurality of HAA values ​​calculated using geometric equations or kinematic models corresponding to the plurality of USS distance measurements, wherein each HAA value corresponds to one of the plurality of USS distance measurements, and each USS distance measurement has a corresponding HAA value; and determine the USS curve characteristics of the first USS. The USS curve features include: a curve fitting function (e.g., a polynomial) mapped to a possible valid cluster of multiple USS distance measurements of the first USS, defining a mathematical relationship between the USS distance measurements in the valid clusters of USS distance measurements and their corresponding HAA values; an upper bound function mapped to the upper boundary of the USS distance measurements in the valid clusters; and a lower bound function mapped to the lower boundary of the USS distance measurements in the valid clusters. The controller is configured to receive USS distance measurements from the first USS when the vehicle is traveling in the reverse direction or experiencing a high HAA, but not from the second USS, which is used in pairs with the first USS distance measurements to calculate the HAA using geometric equations or a kinematic model; estimate the HAA value from the USS distance measurements from the first USS by applying the USS curve features of the first USS; and provide the estimated HAA value to a vehicle motion control system (e.g., trailer reversing assist) for controlling vehicle and trailer motion.

[0016] In some embodiments, a high HAA is an angle at which an accurate USS return cannot be obtained from either of the two USSs in any pair of USSs on the vehicle, which is used to calculate the HAA using geometric equations or kinematic models, but at which an accurate USS return can be obtained from one of the USSs in a pair of USSs.

[0017] In one embodiment, in order to determine the USS curve characteristics of the first USS, the controller is configured to: pair the USS distance measurement of the first USS with the corresponding HAA value to form a USS distance measurement / HAA value (USS-HAA) pair; perform cluster analysis on the USS-HAA pair; identify possible valid clusters of multiple USS distance measurements based on the cluster analysis; and determine a curve fitting function, an upper bound function, and a lower bound function from the possible valid clusters of multiple USS distance measurements.

[0018] In one embodiment, in order to estimate the HAA value from the USS distance measurement from the first USS by applying the USS curve characteristics of the first USS, the controller is configured to filter out the USS distance measurement of the first USS using an upper bound function and a lower bound function.

[0019] In one embodiment, in order to estimate the HAA value from the USS distance measurement from the first USS by applying the USS curve features of the first USS, the controller is further configured to match the USS distance measurement from the first USS with the estimated HAA based on the mathematical relationship between the USS distance measurement in the effective clusters where the USS distance measurement is applied and the corresponding HAA value defined by the curve fitting function.

[0020] In one embodiment, the controller is configured to: receive multiple USS distance measurements for each of a plurality of USSs on the vehicle while the vehicle is towing a trailer in a forward direction; and determine a USS curve feature for each of the plurality of USSs within the range of the received USS distance measurements. The USS curve feature is extended beyond the range in which the USS curve feature was initially constructed to provide the expected range of an acceptable USS-HAA pair extending beyond the range of the received USS distance measurements.

[0021] In one embodiment, the controller is configured to: receive a USS distance measurement from any one of a plurality of USSs when the vehicle is traveling in the opposite direction or experiencing a high HAA, but not receive a USS distance measurement from a second USS, the USS distance measurement from the second USS being used in pairs with a USS distance measurement from one of the plurality of USSs to calculate the HAA using geometric equations or a kinematic model; and estimate the HAA value from the USS distance measurement from one of the plurality of USSs by applying a USS curve feature from one of the plurality of USSs.

[0022] In one embodiment, when the vehicle is experiencing a high HAA, the controller is configured to: estimate the HAA value using appropriate USS curve characteristics; determine whether a HAA value calculated using geometric equations or a kinematic model is available; when a HAA value calculated using geometric equations or a kinematic model is available, select that HAA value to pass to the vehicle motion control; and when a HAA value calculated using geometric equations or a kinematic model is not available, select the estimated HAA value to pass to the vehicle motion control.

[0023] In another embodiment, a method is provided in a vehicle having a HAA calculation system for estimating the articulation angle (HAA) of a hitch between a vehicle and a towed trailer. The method includes: receiving multiple USS distance measurements from a first ultrasonic sensor (USS) on the vehicle when the vehicle is towing the trailer in a forward direction, wherein the USS distance measurement for a particular USS provides a distance measurement between the front of the particular USS and the towed trailer in a particular situation; receiving multiple HAA values ​​calculated using geometric equations or kinematic models corresponding to the multiple USS distance measurements, wherein each HAA value corresponds to one of the multiple USS distance measurements, and each USS distance measurement has a corresponding HAA value; and determining the USS curve characteristics of the first USS. The USS curve features include: a curve fitting function (e.g., a polynomial) that is mapped to possible valid clusters of multiple USS distance measurements of the first USS and defines the mathematical relationship between the USS distance measurements and their corresponding HAA values ​​in the valid clusters of USS distance measurements; an upper bound function that is mapped to the upper boundary of the USS distance measurements in the valid clusters; and a lower bound function that is mapped to the lower boundary of the USS distance measurements in the valid clusters. The mathematical relationships representing these functions are extended beyond the range within which the USS curve features are initially constructed to provide an expected range of acceptable USS-HAA pairs that extends beyond the range of the received USS distance measurements. The method also includes receiving a USS distance measurement from a first USS, but not receiving a USS distance measurement from a second USS, when the vehicle is traveling in the opposite direction or experiencing a high HAA, the USS distance measurement from the second USS being used in pairs with the USS distance measurement from the first USS to calculate the HAA using geometric equations or kinematic models; estimating the HAA value from the USS distance measurement from the first USS by applying the USS curve characteristics of the first USS; and providing the estimated HAA value to a vehicle motion control system (e.g., trailer reversing assist) for controlling the motion of the vehicle and trailer.

[0024] In some embodiments, a high HAA is an angle at which an accurate USS return cannot be obtained from either of the two USSs in any pair of USSs on the vehicle, which is used to calculate the HAA using geometric equations or kinematic models, but at which an accurate USS return can be obtained from one of the USSs in a pair of USSs.

[0025] In one embodiment, determining the USS curve characteristics of the first USS includes: pairing the USS distance measurement of the first USS with the corresponding HAA value to form a USS distance measurement / HAA value (USS-HAA) pair; performing cluster analysis on the USS-HAA pair; identifying possible effective clusters of multiple USS distance measurements based on the cluster analysis; and determining a curve fitting function, an upper bound function, and a lower bound function from the possible effective clusters of multiple USS distance measurements.

[0026] In one embodiment, estimating the HAA value from a USS distance measurement from a first USS by applying the USS curve features of the first USS includes: filtering out the USS distance measurements of the first USS using an upper bound function and a lower bound function; and matching the USS distance measurements from the first USS with the estimated HAA based on the mathematical relationship between the USS distance measurements in the effective clusters where the USS distance measurements are applied and the corresponding HAA values ​​defined by the curve fitting function.

[0027] In one embodiment, the method further includes: receiving multiple USS distance measurements for each of a plurality of USSs on the vehicle while the vehicle is towing a trailer in a forward direction; and determining a USS curve feature for each of the plurality of USSs within the range of the received USS distance measurements. The USS curve feature is extended beyond the range within which the USS curve feature was initially constructed to provide an expected range for an acceptable USS-HAA pair extending beyond the range of the received USS distance measurements.

[0028] In one embodiment, the method further includes receiving a USS distance measurement from any one of a plurality of USSs when the vehicle is traveling in the opposite direction or experiencing a high HAA, but not receiving a USS distance measurement from a second USS, the USS distance measurement of the second USS being used in pairs with a USS distance measurement from one of the plurality of USSs to calculate the HAA using geometric equations or a kinematic model.

[0029] In one embodiment, when the vehicle experiences a high HAA, the method further includes: estimating the HAA value using appropriate USS curve features; determining whether a HAA value calculated using geometric equations or a kinematic model is available; selecting the HAA value to pass to vehicle motion control when the HAA value calculated using geometric equations or a kinematic model is available; and selecting the estimated HAA value to pass to vehicle motion control when the HAA value calculated using geometric equations or a kinematic model is not available.

[0030] In another embodiment, a non-transitory computer-readable medium encoded with programming instructions configurable to cause a controller in a vehicle having a traction articulation angle (HAA) calculation system for estimating the hitch articulation angle (HAA) between the vehicle and the towed trailer to perform a method. The method includes: receiving multiple USS distance measurements from a first ultrasonic sensor (USS) on the vehicle while the vehicle is towing the trailer in a forward direction, wherein the USS distance measurement for a particular USS provides a distance measurement between the frontal faces of the particular USS and the towed trailer under specific conditions; receiving multiple HAA values ​​calculated using geometric equations or kinematic models corresponding to the multiple USS distance measurements, wherein each HAA value corresponds to one of the multiple USS distance measurements, and each USS distance measurement has a corresponding HAA value; and determining a USS curve characteristic of the first USS. The USS curve features include: a curve fitting function (e.g., a polynomial) mapped to a possible valid cluster of multiple USS distance measurements of the first USS, defining a mathematical relationship between the USS distance measurements in the valid clusters and their corresponding HAA values; an upper bound function mapped to the upper boundary of the USS distance measurements in the valid clusters; and a lower bound function mapped to the lower boundary of the USS distance measurements in the valid clusters. The method also includes receiving USS distance measurements from the first USS, but not from the second USS, when the vehicle is traveling in the opposite direction or experiencing a high HAA, the USS distance measurements from the second USS being used in pairs with those from the first USS to calculate the HAA using geometric equations or kinematic models; estimating the HAA value from the USS distance measurements from the first USS by applying the USS curve features of the first USS; and providing the estimated HAA value to a vehicle motion control system for controlling vehicle and trailer motion. Attached Figure Description

[0031] Exemplary embodiments will now be described in conjunction with the following accompanying drawings, wherein the same reference numerals denote the same elements, wherein:

[0032] Figure 1 This is a block diagram illustrating an example vehicle according to an embodiment, the example vehicle including an HAA calculation system that uses ultrasonic sensor (USS) reflections to calculate the hook-up articulation angle (HAA);

[0033] Figure 2 This is a block diagram illustrating an example HAA calculation system according to an embodiment, configured to estimate the HAA between a vehicle and a towed trailer using a single USS distance measurement and USS curve characteristics of the USS providing the USS distance measurement;

[0034] Figure 3A This is a graph illustrating a series of graphs according to an embodiment, showing plots of HAA values ​​determined using geometric equations or kinematic models relative to raw USS distance measurements from the USS.

[0035] Figure 3B This is a graph showing a pair of graphs according to an embodiment, which plot the HAA value of a vehicle with a trailer relative to time.

[0036] Figure 4 This is a block diagram describing an example vehicle and trailer according to an embodiment;

[0037] Figure 5 This is a diagram depicting an example front of a trailer according to an embodiment;

[0038] Figure 6 This is a process flowchart describing an example process for estimating the HAA between a vehicle and a towed trailer according to an embodiment;

[0039] Figure 7 This is a process flowchart describing another example process for estimating the HAA between a vehicle and a towed trailer according to an embodiment. Detailed Implementation

[0040] The following detailed description is merely exemplary in nature and is not intended to limit application or use. Furthermore, it is not intended to be bound by any express or implied theory set forth in the foregoing technical fields, background art, summary of the invention, or the following detailed description. As used herein, the term "module" refers to any hardware, software, firmware, electronic control components, processing logic, and / or processor device, individually or in any combination, including but not limited to: application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), electronic circuits, processors (shared, dedicated, or grouped) and memories executing one or more software or firmware programs, combinational logic circuits, and / or other suitable components providing the described functionality.

[0041] This document describes embodiments of the present disclosure based on functional and / or logical block components and various processing steps. It should be understood that such block components can be implemented by any number of hardware, software, and / or firmware components configured to perform specified functions. For example, embodiments of the present disclosure may employ various integrated circuit components, such as memory elements, digital signal processing elements, logic elements, lookup tables, etc., which can perform various functions under the control of one or more microprocessors or other control devices. Furthermore, those skilled in the art will understand that embodiments of the present disclosure can be practiced in conjunction with any number of systems, and the systems described herein are merely exemplary embodiments of the present disclosure.

[0042] For the sake of brevity, conventional techniques related to signal processing, data transmission, signaling, control, machine learning models, radar, lidar, image analysis, and other functional aspects of the system (as well as the various operating components of the system) may not be described in detail herein. Furthermore, the connecting lines shown in the various figures contained herein are intended to represent exemplary functional relationships and / or physical connections between the various elements. It should be noted that many alternative or additional functional relationships or physical connections may exist in the embodiments of this disclosure.

[0043] Autonomous and semi-autonomous vehicles are capable of sensing their environment and navigating based on that sensing. Such vehicles utilize various types of sensing devices to perceive their environment, such as optical cameras, radar, lidar, and other image sensors. In these vehicles, the sensed data can be fused with map data and vehicle sensor data (inertial measurement units, vehicle speed sensors, etc.) to identify and track vehicle trajectory performance based on road geometry, and can be used in this disclosure for motion modeling and for estimating the hitch articulation angle (HAA) to enhance traction stability when towing a trailer.

[0044] For comparative reasons, current methods for calculating the hitch articulation angle (HAA) using ultrasonic sensor (USS) reflections require the availability of at least two sensors. Typically, due to the lack of sensor reflections, the calculation of the HAA angle using USS reflections cannot be used for higher trailer hitch angles. The disclosed topics include methods that allow the calculation of the HAA angle using USS reflections, even when only reflections from a single sensor are available. This extends the range of HAAs that can be calculated using only raw USS distance measurements. This method is particularly useful because a kinematic model is lacking in reverse mode.

[0045] Furthermore, due to noise from USS reflections, estimations of HAA at higher angles using other methods may also be inaccurate. The disclosed topics include methods that allow for better estimation of HAA at higher angles, even in the case of reflections from a single sensor.

[0046] Figure 1 This is a block diagram illustrating an example vehicle 10, which includes a hitch articulation angle (HAA) calculation system 100 that uses ultrasonic sensor (USS) reflections to calculate the hitch articulation angle (HAA). In many operating conditions, at least two sensors are available for calculating the HAA. However, in cases of higher trailer hitch angles, only one sensor may be available due to a lack of sensor reflections. The disclosed HAA calculation system 100 can estimate the HAA for many higher trailer hitch angle cases using raw USS distance measurements, even when only one sensor is available. This is particularly useful in situations where a kinematic model is unavailable, such as when the towing vehicle and trailer are operating in reverse mode.

[0047] like Figure 1 As shown, the example vehicle 10 typically includes a chassis 12, a body 14, front wheels 16, and rear wheels 18. The body 14 is mounted on the chassis 12 and substantially surrounds the components of the vehicle 10. The body 14 and chassis 12 may together form a frame. The wheels 16-18 are each rotatably connected to the chassis 12 near a corresponding corner of the body 14. In the illustrated embodiment, the vehicle 10 is described as a passenger vehicle, but other types of vehicles may also be used, including trucks, sport utility vehicles (SUVs), recreational vehicles (RVs), etc. The vehicle 10 is capable of manual, autonomous, and / or semi-autonomous driving.

[0048] The vehicle 10 also includes a propulsion system 20, a transmission system 22 that transmits power from the propulsion system 20 to the wheels 16-18, a steering system 24 that affects the position of the wheels 16-18, a braking system 26 that provides braking torque to the wheels 16-18, a sensor system 28, an actuator system 30, at least one data storage device 32, at least one controller 34, and a communication system 36 configured to wirelessly communicate information with other entities 48.

[0049] Sensor system 28 includes one or more sensing devices 40a-40r that sense observable conditions of the external and / or internal environment of the autonomous vehicle 10. Sensing devices 40a-40r may include, but are not limited to, radar, lidar, global positioning system, optical camera, thermal camera, ultrasonic sensor (e.g., 40o-40r), inertial measurement unit, ultra-wideband sensor, and / or other sensors. Actuator system 30 includes one or more actuator devices 42a-42n that control one or more vehicle features, such as, but not limited to, propulsion system 20, drivetrain 22, steering system 24, and braking system 26.

[0050] Data storage device 32 stores data used for automatically controlling vehicle 10. Data storage device 32 may be part of controller 34, separate from controller 34, or part of controller 34 and a separate system. Controller 34 includes at least one processor 44 and a computer-readable storage device or medium 46. Although in Figure 1 Only one controller 34 is shown, but embodiments of vehicle 10 may include any number of controllers 34 that communicate via any suitable communication medium or combination of communication media and cooperate to process sensor signals, perform logic, calculations, methods and / or algorithms, and generate control signals to automatically control the features of vehicle 10.

[0051] Processor 44 can be any custom or commercially available processor, central processing unit (CPU), graphics processing unit (GPU), auxiliary processor among multiple processors associated with controller 34, semiconductor-based microprocessor (in the form of a microchip or chipset), macroprocessor, any combination thereof, or any device generally used for executing instructions. Computer-readable storage device or medium 46 can include volatile and non-volatile storage, such as read-only memory (ROM), random access memory (RAM), and keep-alive memory (KAM). KAM is a permanent or non-volatile memory that can be used to store various operational variables when processor 44 is powered off. Computer-readable storage device or medium 46 can be implemented using any of a variety of known storage devices, such as PROM (programmable read-only memory), EPROM (electrical PROM), EEPROM (electrically erasable PROM), flash memory, or any other electrical, magnetic, optical, or combined storage device capable of storing data, some of which represent executable instructions used by controller 34.

[0052] The programming instructions may include one or more separate programs, each comprising an ordered list of executable instructions for implementing logical functions. When executed by processor 44, one or more instructions of controller 34 may configure vehicle 10 to estimate the HAA between vehicle and towed trailer using a single USS distance measurement and USS curve characteristics of the USS providing the USS distance measurement.

[0053] The HAA computing system 100 may include any number of additional submodules embedded within the controller 34, which may be combined and / or further subdivided to similarly implement the systems and methods described herein. Additionally, inputs to the HAA computing system 100 may be received from the sensor system 28, from other control modules (not shown) associated with the vehicle 10, and / or by… Figure 1 Other submodules (not shown) within the controller 34 are determined / modeled. Furthermore, the input may undergo preprocessing such as subsampling, noise reduction, normalization, feature extraction, and loss reduction.

[0054] Figure 2This is a block diagram depicting an example HAA calculation system 200 configured to estimate the HAA between a vehicle and a towed trailer using a single USS distance measurement and the USS curve characteristics of the USS providing the USS distance measurement. The example HAA calculation system takes the raw USS measurement 201 as input along with the corresponding HAA value 203 calculated by geometric equations or a kinematic model. The example HAA calculation system 200 includes a USS curve generation module 202, a single-sensor HAA calculation module 204, and a larger angle HAA calculation module 206. The example HAA calculation system 200, USS curve generation module 202, single-sensor HAA calculation module 204, and larger angle HAA calculation module 206 can be implemented by a controller 34.

[0055] Figure 3A These are graphs 300, 320, 330, 340, and 350, depicting HAA values ​​determined using geometric equations or kinematic models relative to original USS distance measurements from the USS. Graph 320 provides a plot of HAA values ​​relative to original USS distance measurements from the first USS on the vehicle. Graph 330 provides a plot of HAA values ​​relative to original USS distance measurements from the second USS on the vehicle. Graph 340 provides a plot of HAA values ​​relative to original USS distance measurements from the third USS on the vehicle. Graph 350 provides a plot of HAA values ​​relative to original USS distance measurements from the fourth USS on the vehicle. Graph 300 shows an example of graphs 320, 330, 340, and 350 after performing clustering and curve fitting operations. Graph 300 depicts a curve fitting function 302 (e.g., a curve fitting polynomial) mapped to a possible valid cluster 304 of multiple USS distance measurements for a specific USS, and defines a mathematical relationship (e.g., mathematical relationship 306) between the USS distance measurements in the possible valid cluster 304 and their corresponding HAA values. It also depicts an upper bound function (e.g., upper bound curve 308) mapping to the upper boundary of the USS distance measurements in the possible valid cluster 304 and a lower bound function (e.g., lower bound curve 310) mapping to the lower boundary of the USS distance measurements in the possible valid cluster 304.

[0056] Figure 3BThese are graphs 360 and 370, depicting a pair of curves showing the HAA value of a vehicle with a trailer plotted against time. Graph 360 depicts the HAA value determined for the vehicle using a pair of USS distance measurements and geometric equations or a kinematic model. Graph 370 depicts the HAA value determined for the vehicle using a pair of USS distance measurements and geometric equations or a kinematic model, combined with an estimated HAA value calculated using geometric equations or a kinematic model, obtained using the techniques described herein.

[0057] Figure 4 This is a block diagram depicting example vehicle 402 and trailer 404. It depicts the HAA410 "φ" between vehicle 402 and trailer 404, which can be calculated based on geometric equations. In this example, the distance l is based on the vehicle wheelbase. w 415. Distance l between the vehicle's rear axle and the engagement point h 420. Distance l between the attachment point and the trailer's rear axle tr A set of measurements, including 425° and the vehicle wheel angle δ435°, are used to calculate HAA410 "φ". An example geometric equation for calculating HAA410 "φ" is as follows:

[0058]

[0059] Among them, V c 430 is the longitudinal velocity of the vehicle, and δ435 is the wheel angle determined by the steering angle input from the vehicle driver. The kinematic model of the trailer can be obtained by measuring l of vehicle 402 / trailer 404 over time t. w ,l tr ,l h This is used to derive the formula for calculating HAA410 "φ".

[0060] Figure 5 This is a diagram depicting an example front section 500 of a trailer. The example front section 500 has a V-shape and includes a first front face 502 and a second front face 504. A HAA506 "φ" is depicted between the rear section 508 of the vehicle (e.g., a bumper) and the front section 500 of the trailer, which can be calculated based on geometric equations. In this example, HAA506 "φ" is calculated based on the following geometric equations:

[0061]

[0062] Where d1(509) is the distance measured by sensor 1 (USS1) 510, d4(511) is the distance measured by sensor 4 (USS4), and L hitch512 is the distance between the vehicle bumper 508 and the attachment point 514, L1(516) is the distance between the midpoint of the vehicle bumper and sensor 1 510 (USS1), L4(518) is the distance between the midpoint of the vehicle bumper and sensor 4 (USS4) 520, and α(522) is the face angle of the trailer front. This equation can be solved numerically to obtain the unknown value of HAA, represented by φ.

[0063] refer to Figure 2 , 3A Examples 3B, 4, and 5, the USS curve generation module 202, is configured to tow a trailer in the forward or reverse direction when the vehicle is towing it (e.g., ...). Figure 4 When receiving a trailer (404), the vehicle (e.g.) Figure 4 Specific USS (e.g., on vehicle 402) Figure 5 Multiple ultrasonic sensor (USS) distance measurements 201 for USS1. Multiple USS distance measurements 201 can be stored in data storage 208. USS distance measurements for a specific USS (e.g., USS1) (e.g.,...) Figure 5 d1) provides a distance measurement between a specific USS and the front 502 of the towed trailer under specific conditions. The example USS curve generation module 202 is also configured to receive multiple HAA values ​​203 calculated using geometric equations or kinematic models corresponding to multiple USS distance measurements (e.g., ...). Figure 4 φ410 or Figure 5 The HAA value corresponds to one of multiple USS distance measurements, and each USS distance measurement has a corresponding HAA value. Example USS curve generation module 202 can perform curve generation using a selected, finite range of corresponding HAA-USS values. Multiple HAA values ​​203 can also be stored in data storage 208.

[0064] The example USS curve generation module 202 is also configured to determine USS curve features for a specific USS. These USS curve features include a curve fitting function 302, which is mapped to a possible valid cluster 304 of multiple USS distance measurements for the specific USS, and defines a mathematical relationship (e.g., mathematical relationship 306) between the USS distance measurements in the possible valid cluster 304 and their corresponding HAA values. The USS curve features also include an upper bound function (e.g., upper bound curve 308) mapped to the upper boundary of the USS distance measurements in the possible valid cluster 304, and a lower bound function (e.g., lower bound curve 310) mapped to the lower boundary of the USS distance measurements in the possible valid cluster 304.

[0065] To determine the USS curve characteristics of a specific USS, the USS curve generation module 202 is configured to pair the USS distance measurement of the specific USS with the corresponding HAA value (e.g., in the data storage 208) to form a USS distance measurement / HAA value (USS-HAA) pair; perform cluster analysis on the USS-HAA pair; identify possible valid clusters (e.g., possible clusters 304) of multiple USS distance measurements based on the cluster analysis; and determine the curve fitting function 302, the upper bound curve 308, and the lower bound curve 310 from the possible valid clusters 304 of multiple USS distance measurements.

[0066] USS curve generation module 202 can be configured to receive multiple USS distance measurements of each of a plurality of USS on the vehicle when the vehicle is towing a trailer in both forward and reverse directions, and determine the USS curve characteristics of each of the plurality of USS within the range of the received USS distance measurements, such as Figure 3A As shown, the USS curve features are extended beyond the range in which the USS curve features were originally constructed to provide the expected range of an acceptable USS-HAA pair that extends beyond the range of the received USS distance measurement.

[0067] Example single-sensor HAA calculation module 204 is configured to receive a specific USS (e.g., when the vehicle is traveling in the opposite direction or experiencing a high HAA) Figure 5 USS distance measurement 205 (e.g., USS1 or USS4) Figure 5 The distance to the second USS (d1 or d4) is used in pairs with the distance to a specific USS to calculate the HAA using geometric equations or kinematic models. A high HAA can be an angle at which an accurate USS return cannot be obtained from either of the two USSs in a pair on the vehicle, which is used to calculate the HAA using geometric equations or kinematic models, but at which an accurate USS return can be obtained from one of the USSs in a pair.

[0068] The example single-sensor HAA calculation module 204 is also configured to estimate HAA values ​​207 from USS distance measurements 205 from a specific USS by applying USS curve features (e.g., 302, 308, 310) of that specific USS. To estimate HAA values ​​from USS distance measurements from a specific USS by applying USS curve features, the single-sensor HAA calculation module 204 can use an upper bound function (e.g., upper bound curve 308) and a lower bound function (e.g., lower bound curve 310) to filter out USS distance measurements from that specific USS, and / or match the USS distance measurements from that specific USS to the estimated HAA based on a mathematical relationship between USS distance measurements in effective clusters where USS distance measurements are applied and the corresponding HAA values ​​defined by the curve fitting function 302.

[0069] The single-sensor HAA calculation module 204 can be configured to receive USS distance measurements from any one of the multiple USSs on the vehicle when the vehicle is traveling in the opposite direction or experiencing a high HAA, but not receive USS distance measurements from a second USS. The USS distance measurement from the second USS is used in pairs with the USS distance measurement from one of the multiple USSs to calculate the HAA using geometric equations or kinematic models, and to estimate the HAA value from the USS distance measurement from one of the multiple USSs by applying the USS curve characteristics of one of the multiple USSs.

[0070] Example: The larger angle HAA calculation module 206 is configured to, when the vehicle experiences a high HAA, use appropriate USS curve features to estimate the HAA value, determine whether the HAA value calculated using geometric equations or a kinematic model is available, and if the HAA value calculated using geometric equations or a kinematic model is available, select that HAA value as the calculated HAA 209 and pass it to the vehicle motion control; and if the HAA value calculated using geometric equations or a kinematic model is unavailable, select the estimated HAA value as the calculated HAA 209 and pass it to the vehicle motion control. Figure 3B As shown in graph 360, during high HAA times (e.g., 362, 364, 366, 368), when the vehicle experiences high HAA, determining the HAA value using geometric equations or kinematic models may not be available. However, (as shown in graph 370) the estimated HAA value calculated from the curve of module 204 can be combined with the HAA value calculated using geometric equations or kinematic models to provide an estimated HAA value during high HAA times (e.g., 362, 364, 366, 368).

[0071] Figure 6 This is a process flow diagram describing example process 600 for estimating the HAA between a vehicle and a towed trailer. The sequence of operations within process 600 is not limited to... Figure 6The execution may not be performed in the order shown, but may be performed in one or more different orders as applicable and in accordance with this disclosure.

[0072] Example process 600 includes storing the corresponding original USS range 603 / HAA value 605 (operation 602) as the vehicle and trailer travel in the forward direction. The HAA value 605 can be calculated using geometric equations or kinematic models.

[0073] Example procedure 600 includes performing clustering to identify potentially valid clusters of USS range 603 / HAA value 605, curve fitting the potentially valid clusters, and defining the boundaries of the potentially valid clusters (operation 604). These operations are performed to define the USS curve characteristics 607 of the USS.

[0074] Example process 600 includes filtering the received raw USS range 609 (operation 606) based on USS curve features 607 when the vehicle and trailer are traveling in opposite directions. Example process 600 also includes estimating HAA using USS curve features 607 when the vehicle and trailer are traveling in opposite directions (operation 608).

[0075] Example process 600 includes merging curve-calculated HAA values ​​with HAA values ​​calculated using geometric equations or kinematic models when the vehicle and trailer are experiencing a large hitch articulation angle (operation 610). This may include obtaining curve-calculated HAA values ​​611, obtaining HAA values ​​calculated using geometric equations or kinematic models 613, selecting the HAA value for use when the HAA value calculated using geometric equations or kinematic models is available, and selecting an estimated HAA value for use when the HAA value calculated using geometric equations or kinematic models is unavailable. This results in a merging series of HAAs 615, particularly for larger HAAs when the use of geometric equations or kinematic models may be unavailable.

[0076] Figure 7 This is a process flow diagram describing example process 700 for estimating the HAA between a vehicle and a towed trailer. The sequence of operations within process 700 is not limited to... Figure 7 The execution may not be performed in the order shown, but may be performed in one or more different orders as applicable and in accordance with this disclosure.

[0077] Example process 700 includes receiving distance measurements from multiple ultrasonic sensors (USS) on a specific USS on the vehicle when the vehicle is towing a trailer in the forward direction (operation 702). The USS distance measurement of the specific USS provides a distance measurement between the specific USS and the front of the towed trailer under specific conditions.

[0078] Example process 700 includes receiving multiple HAA values ​​calculated using geometric equations or kinematic models corresponding to multiple USS distance measurements (operation 704). Each HAA value corresponds to one of the multiple USS distance measurements, and each USS distance measurement has a corresponding HAA value.

[0079] Example procedure 700 includes determining the USS curve features of a particular USS (operation 706). The USS curve features include: a curve fitting function, which is mapped to a possible valid cluster of multiple USS distance measurements for a particular USS and defines the mathematical relationship between the USS distance measurements and their corresponding HAA values ​​in the valid clusters of USS distance measurements; an upper bound function, which is mapped to the upper boundary of the USS distance measurements in the valid clusters; and a lower bound function, which is mapped to the lower boundary of the USS distance measurements in the valid clusters.

[0080] Determining the USS curve characteristics of a specific USS may include: pairing the USS distance measurement of the specific USS with the corresponding HAA value to form a USS distance measurement / HAA value (USS-HAA) pair; performing cluster analysis on the USS-HAA pair; identifying possible effective clusters of multiple USS distance measurements based on the cluster analysis; and determining the curve fitting function, upper bound function, and lower bound function from the possible effective clusters of multiple USS distance measurements.

[0081] Example process 700 includes receiving a USS distance measurement from a specific USS when the vehicle is traveling in the opposite direction or experiencing a high HAA (operation 708), but not receiving a USS distance measurement from a second USS, which is used in pairs with the USS distance measurement from the specific USS to calculate the HAA using geometric equations or kinematic models.

[0082] Example process 700 includes estimating the HAA value from USS distance measurements from a specific USS by applying USS curve features to that specific USS (operation 710). Estimating the HAA value from USS distance measurements from a specific USS by applying USS curve features to that specific USS may include: filtering out USS distance measurements from the specific USS using an upper bound function and / or a lower bound function; and matching the USS distance measurements from the specific USS to the estimated HAA based on a mathematical relationship between the USS distance measurements in an effective cluster where the USS distance measurements are applied and the corresponding HAA value defined by a curve fitting function.

[0083] Example process 700 includes providing an estimated HAA value to a vehicle motion control system for controlling vehicle and trailer motion (operation 712). Example process 700 may also include receiving multiple USS distance measurements for each of a plurality of USSs on the vehicle while the vehicle is towing a trailer in a forward direction, and determining a USS curve feature for each of the plurality of USSs within the range of the received USS distance measurements, wherein the USS curve feature is extended beyond the range in which the USS curve feature was initially constructed to provide an expected range of an acceptable USS-HAA pair extending beyond the range of the received USS distance measurements. Example process 700 may also include receiving USS distance measurements for any one of the plurality of USSs when the vehicle is traveling in a reverse direction or experiencing a high HAA, but not receiving USS distance measurements from a second USS, the USS distance measurement of the second USS being used in pairs with the USS distance measurement of one of the plurality of USSs to calculate the HAA using geometric equations or a kinematic model.

[0084] The foregoing summary outlines features of various embodiments, enabling those skilled in the art to better understand various aspects of this disclosure. Those skilled in the art will understand that this disclosure can be readily used as the basis for designing or modifying other processes and structures to achieve the same purposes and / or advantages of the embodiments described herein. Those skilled in the art should also recognize that such equivalent constructions do not depart from the spirit and scope of this disclosure, and that various changes, substitutions, and modifications can be made herein without departing from the spirit and scope of this disclosure.

Claims

1. A HAA calculation system for estimating the articulation angle (HAA) of a coupling device between a vehicle and a towed trailer in a vehicle, the HAA calculation system comprising a controller configured to: As the vehicle tows the trailer in the forward direction, it receives multiple USS distance measurements from the first ultrasonic sensor (USS) on the vehicle. USS distance measurement for a specific USS provides a distance measurement between the front of a specific USS and the towed trailer under specific conditions; Receive multiple HAA values ​​calculated using geometric equations or kinematic models corresponding to multiple USS distance measurements, wherein each HAA value corresponds to one of the multiple USS distance measurements, and each USS distance measurement has a corresponding HAA value; Determine the USS curve characteristics of the first USS, wherein the USS curve characteristics include: A curve fitting function is mapped to a possible valid cluster of multiple USS distance measurements of the first USS, and a mathematical relationship is defined between the USS distance measurement and the corresponding HAA value in the valid cluster of USS distance measurements. An upper bound function, which is mapped to the upper boundary of the USS distance measure in the effective clusters; and The lower bound function, which is mapped to the lower bound of the USS distance measurement in the effective cluster; When the vehicle is traveling in the opposite direction or experiencing a high HAA, the USS distance measurement from the first USS is received, but the USS distance measurement from the second USS is not received. The USS distance measurement from the second USS is used in pairs with the USS distance measurement from the first USS to calculate the HAA using geometric equations or kinematic models. The HAA value is estimated from the USS distance measurement from the first USS by applying the USS curve characteristics of the first USS; and The estimated HAA value is provided to the vehicle motion control system for controlling the movement of the vehicle and trailer.

2. The HAA computing system according to claim 1, wherein, To determine the USS curve characteristics of the first USS, the controller is configured as follows: Pair the USS distance measurement of the first USS with the corresponding HAA value to form a USS-HAA pair of USS distance measurement / HAA value; Cluster analysis was performed on the USS-HAA pairs; Cluster analysis was used to identify potentially valid clusters for multiple USS distance measurements; and The curve fitting function, upper bound function, and lower bound function are determined from the possible effective clustering of multiple USS distance measurements.

3. The HAA computing system according to claim 1, wherein, In order to estimate the HAA value from the USS distance measurement from the first USS by applying the USS curve characteristics of the first USS, the controller is configured to: The USS distance measurement of the first USS is filtered out using the upper and lower bound functions. as well as Based on the mathematical relationship between the USS distance measurement in the effective cluster of the applied USS distance measurement and the corresponding HAA value defined by the curve fitting function, the USS distance measurement from the first USS is matched with the estimated HAA.

4. The HAA computing system according to claim 1, wherein, The controller is configured as follows: When the vehicle is towing a trailer in the forward direction, multiple USS distance measurements are received for each of the multiple USS on the vehicle. as well as Determine the USS curve characteristics of each of a plurality of USSs within the range of the received USS distance measurement, wherein the USS curve characteristics are extended beyond the range in which the USS curve characteristics were originally constructed, to provide the expected range of an acceptable USS-HAA pair extending beyond the range of the received USS distance measurement.

5. The HAA computing system according to claim 4, wherein, The controller is configured as follows: When the vehicle is traveling in the opposite direction or experiencing a high HAA, the USS distance measurement of any one of the multiple USS is received, but the USS distance measurement from the second USS is not received. The USS distance measurement of the second USS is used in pairs with the USS distance measurement of one of the multiple USS to calculate the HAA using geometric equations or kinematic models. as well as The HAA value is estimated from a USS distance measurement from one of multiple USSs by applying the USS curve characteristics of one of multiple USSs.

6. The HAA computing system according to claim 1, wherein, When the vehicle experiences a high HAA, the controller is configured to: Estimate the HAA value using appropriate USS curve characteristics; Determine if the HAA value calculated using geometric equations or kinematic models is available; When a HAA value calculated using geometric equations or kinematic models is available, select that HAA value and pass it to the vehicle motion control. as well as When the HAA value calculated using geometric equations or kinematic models is unavailable, an estimated HAA value is selected and passed to the vehicle motion control.

7. A method in a vehicle having an HAA calculation system for estimating the articulation angle HAA of the coupling device between the vehicle and the towed trailer, the method comprising: When the vehicle is towing a trailer in the forward direction, multiple USS distance measurements are received from the first ultrasonic sensor USS on the vehicle, wherein the USS distance measurement of a specific USS provides a distance measurement between the front of the specific USS and the towed trailer under a specific condition. Receive multiple HAA values ​​calculated using geometric equations or kinematic models corresponding to multiple USS distance measurements, wherein each HAA value corresponds to one of the multiple USS distance measurements, and each USS distance measurement has a corresponding HAA value; Determine the USS curve characteristics of the first USS, wherein the USS curve characteristics include: A curve fitting function is mapped to a possible valid cluster of multiple USS distance measurements of the first USS, and a mathematical relationship is defined between the USS distance measurement and the corresponding HAA value in the valid cluster of USS distance measurements. An upper bound function, which is mapped to the upper boundary of the USS distance measure in the effective clusters; and The lower bound function, which is mapped to the lower bound of the USS distance measurement in the effective cluster; When the vehicle is traveling in the opposite direction or experiencing a high HAA, the USS distance measurement from the first USS is received, but the USS distance measurement from the second USS is not received. The USS distance measurement from the second USS is used in pairs with the USS distance measurement from the first USS to calculate the HAA using geometric equations or kinematic models. The HAA value is estimated from the USS distance measurement from the first USS by applying the USS curve characteristics of the first USS; and The estimated HAA value is provided to the vehicle motion control system for controlling the movement of the vehicle and trailer.

8. The method according to claim 7, wherein, The characteristics of the USS curve for determining the first USS include: Pair the USS distance measurement of the first USS with the corresponding HAA value to form a USS-HAA pair of USS distance measurement / HAA value; Cluster analysis was performed on the USS-HAA pairs; Cluster analysis was used to identify potentially valid clusters for multiple USS distance measurements; and The curve fitting function, upper bound function, and lower bound function are determined from the possible effective clustering of multiple USS distance measurements.

9. The method according to claim 7, wherein, Estimating the HAA value from a USS distance measurement from a first USS by applying the USS curve characteristics of the first USS includes: The USS distance measurement for the first USS is filtered using the aforementioned upper and lower bound functions; and Based on the mathematical relationship between the USS distance measurement in the effective cluster of the applied USS distance measurement and the corresponding HAA value defined by the curve fitting function, the USS distance measurement from the first USS is matched with the estimated HAA.

10. The method according to claim 7, wherein, When a vehicle experiences a high HAA, the method also includes: Estimate the HAA value using appropriate USS curve characteristics; Determine if the HAA value calculated using geometric equations or kinematic models is available; When a HAA value calculated using geometric equations or kinematic models is available, select that HAA value and pass it to the vehicle motion control; and When the HAA value calculated using geometric equations or kinematic models is unavailable, an estimated HAA value is selected and passed to the vehicle motion control.

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