SYSTEM AND METHOD FOR DETERMINING THE NUMBER AND POSITION OF TRAILER AXLES

Abstract

A method for determining the number of trailer axles and the axle position of a trailer relative to a vehicle. The method includes receiving vehicle operating characteristics from at least one sensor on the vehicle and determining whether the vehicle has encountered a bump in the roadway, based on at least one of the vehicle operating characteristics. The method determines whether at least one trailer axle has encountered the bump and analyzes the relative time difference between the time the vehicle encountered the bump and the time the at least one trailer axle encountered it. The method uses this relative time to determine the number of trailer axles and to estimate the position of the at least one trailer axle relative to the vehicle.

Description

introduction

[0001] The present description relates to the determination of the position of a trailer axle and, in particular, to the determination of the position of the trailer axle relative to a towing vehicle.

[0002] When towing a trailer, the driver of a towing vehicle encounters several obstacles. Towing a trailer can affect the dynamics of the towing vehicle and require the driver to operate the vehicle differently due to the added length of the trailer. Furthermore, the trailer may move relative to the towing vehicle during certain maneuvers, such as reversing, necessitating adjustments to the towing vehicle's inputs compared to reversing without a trailer. Additionally, the extra weight of the trailer can affect the towing vehicle's braking performance.

[0003] DE 11 2020 000 325 T5 describes a system and a method for estimating the properties of a trailer. The system comprises a trailer, a vehicle with a sensor, a camera, and an electronic control unit configured to receive initial data from the sensor and / or camera at a first location relative to the trailer, determine a second location relative to the trailer for the vehicle (the second location being different from the first), generate a signal to move the vehicle from the first location to the second location, receive second data from the sensor and / or camera at the second location, determine a property of the trailer based on the first and second data, and determine the trailer's movement behavior based on the property before the vehicle is coupled to the trailer.

[0004] DE 20 2011 100 844 U1 describes a train consisting of a towing vehicle and at least one trailer electrically and mechanically coupled to the towing vehicle, wherein the towing vehicle includes at least one bus module, sensor modules, control modules and a data bus, and the bus module, control modules and sensor modules communicate with each other via the data bus in order to generate control signals relating to the driving dynamics from signals of the sensor modules, which act on the driving dynamics via the control modules.The trailer includes a trailer bus module, at least one trailer control module, and a trailer data bus, wherein the trailer bus module and the trailer control module communicate with each other via the trailer data bus, and the trailer data bus communicates with the data bus in the towing vehicle via a data interface in order to transmit control signals relating to driving dynamics and / or signals from sensor modules in the towing vehicle to the at least one trailer control module and / or to the trailer bus module.

[0005] DE 198 59 646 A1 describes a method and a device for determining the speed of a land vehicle within the vehicle. To make unauthorized manipulation of the speed measurement more difficult, it is provided that the time interval of similar vibration peaks, essentially vertical vibrations in the direction of travel, of components arranged one behind the other, in particular wheel axles, on which the same irregularities of the driving surface, especially road or rail, act, is determined as a measure of speed. Description

[0006] It can be considered an object of the present invention to facilitate driving a vehicle with a trailer. This object is achieved by the subject matter of claim 1. Advantageous embodiments are described in the dependent claims.

[0007] This document describes a method for determining the number and position of a trailer axle relative to a vehicle. The method involves receiving vehicle operating characteristics from at least one sensor on the vehicle and determining whether the vehicle has encountered a bump in the road surface, based on at least one of these characteristics. The method then determines whether at least one trailer axle has struck the bump and analyzes the relative time difference between when the vehicle struck the bump and when the at least one trailer axle struck it. Using this relative time, the method determines the number of trailer axles and estimates the position of the at least one trailer axle relative to the vehicle.

[0008] Another aspect of the disclosure may include determining an enabling excitation of the vehicle when the vehicle hits the bump, and the enabling excitation includes identifying at least one of a steering angle of the vehicle that is within a predetermined range, a speed of the vehicle that is greater than a predetermined speed, or a difference in wheel rotation speed between laterally spaced wheels of the vehicle that is less than a predetermined value.

[0009] Another aspect of the description may include confirming the presence of the trailer coupled to the vehicle by estimating the position of at least one trailer axle relative to the vehicle.

[0010] Another aspect of the disclosure may include that the at least one sensor comprises at least one ride height sensor, a wheel speed sensor, or an inertial measurement unit located on the vehicle. Determining whether the vehicle has hit the bump is based on determining the amplitude of a rate of change of the at least one vehicle operating characteristic.

[0011] Another aspect of the disclosure may include that the at least one sensor is located on the vehicle and that determining whether the at least one trailer axle has hit the bump is based on determining an amplitude of a rate of change of at least one of the vehicle operating characteristics within a time frame after the vehicle has hit the bump.

[0012] Another aspect of the disclosure may include determining the status of the trailer by determining whether the amplitude of the rate of change of at least one vehicle operating characteristic is within a specified range.

[0013] Another aspect of the disclosure may include receiving a second set of vehicle operating characteristics from the at least one sensor on the vehicle and determining, based on at least one of the second set of vehicle operating characteristics, whether the vehicle encountered a second bump in the roadway. The method determines whether at least one trailer axle struck the bump and analyzes a relative time difference between the time the vehicle struck the bump and the time the at least one trailer axle struck the bump in order to determine a second number of trailer axles and to estimate a second position of the at least one trailer axle relative to the vehicle.The procedure identifies a change in the operating state of the trailer when a difference between the second position of the at least one trailer axle and the position of the at least one trailer axle exceeds a predetermined threshold.

[0014] Another aspect of the disclosure may include determining whether the vehicle hit the bump, determining an estimated wheelbase length for the vehicle based on the vehicle's speed and a relative time difference between the time a front wheel of the vehicle hit the bump and the time a rear wheel of the vehicle hit the bump.

[0015] Another aspect of the disclosure may include that if the estimated wheelbase length is within a predetermined range of a predetermined wheelbase length for the vehicle, the vehicle has hit the bump.

[0016] Another aspect of the disclosure may involve determining the estimated wheelbase length by integrating the vehicle's speed from the moment one of the two front wheels hits the bump until the moment one of the two rear wheels hits the bump.

[0017] Another aspect of the disclosure may include the determination of whether at least one trailer axle has hit the bump in the road, based on the at least one vehicle sensor being configured to measure when at least one longitudinal jerk, yaw acceleration, or pitch acceleration exceeds a corresponding predetermined threshold.

[0018] Another aspect of the disclosure may include the fact that determining whether the at least one trailer axle has hit the bump involves identifying a reduction in the vibration amplitude of at least one of the longitudinal acceleration, the yaw acceleration and / or the pitch acceleration.

[0019] This discloses a non-volatile, computer-readable medium containing programmed instructions that, when executed by a processor, are suitable for carrying out a method. The method comprises receiving vehicle operating characteristics from at least one sensor on the vehicle and determining, based on at least one of the vehicle operating characteristics, whether the vehicle has encountered a bump in the roadway. The method determines whether at least one trailer axle has encountered the bump and analyzes a relative time difference between the time the vehicle encountered the bump and the time the at least one trailer axle encountered it. The method uses this relative time to determine the number of trailer axles and to estimate the position of the at least one trailer axle relative to the vehicle.

[0020] This document discloses a vehicle assembly. The vehicle assembly comprises a vehicle body with a front axle supported by a front pair of wheels and a rear axle supported by a rear pair of wheels, as well as at least one sensor configured to measure the movement of the front axle and / or the rear axle and / or the vehicle body. The vehicle assembly also includes a controller electrically connected to the at least one sensor. The controller is configured to receive vehicle operating characteristics from at least one sensor on the vehicle and, based on at least one of these characteristics, determines whether the vehicle has encountered a bump in the roadway.The control system is also configured to determine whether at least one trailer axle has hit the bump, and to analyze a relative time difference between the time the vehicle hit the bump and the time the at least one trailer axle hit the bump in order to estimate at least one of a number of trailer axles or axle position. Brief description of the drawings Fig. Figure 1 is a schematic representation of a vehicle system with a vehicle and a trailer. Fig. Figure 2 shows an example of a method for determining the number and position of trailer axles. Fig. Figure 3 shows a graphical representation of a state parameter of the vehicle. Fig. 1, measured over a specific period of time. Fig. Figure 4A shows a graphical representation of the rate of change of a state parameter of Fig. 3, measured over a specific period of time. Fig. Figure 4B shows a graphical representation of a time-based amplitude-phase analysis of the in Fig. 4A shows the rate of change over a specific period. Fig. Figure 5 shows a graphical representation of an estimate of the position of the trailer axle. Fig. Figure 6 shows another example of a method for determining the number and position of axles of a trailer. Fig. Figure 7 is a graphical representation of the movement of a front axle of the vehicle. Fig. 1. Fig. Figure 8 is a graphical representation of the movement of a rear axle of the vehicle. Fig. 1. Fig. Figure 9 is a graphical representation of an example of the inertial motion of the vehicle of Fig. 1, when two axles of the trailer drive over a bump in the road. Fig. Figure 10 is a graphical representation of an example for determining the number of trailer axles. Fig. Figure 11 is a graphical representation of an example for determining the position of the trailer axle. Detailed description

[0021] The present description can be implemented in many different forms. Representative examples of the description are shown in the drawings and are described in detail herein as non-restrictive examples of the disclosed principles. For this purpose, elements and restrictions described in the sections "Summary," "Introduction," "Description," and "Detailed Description," but not expressly included in the claims, should not be considered, individually or collectively, as included in the claims, either by implication, inference, or otherwise.

[0022] For the purposes of this description, the use of the singular includes the plural and vice versa, unless expressly excluded. The terms "and" and "or" apply in both the subjunctive and disjunctive moods, and the words "including," "containing," "comprising," "exhibiting," and the like mean "including without limitation." Furthermore, words of approximation such as "about," "almost," "essentially," "generally," "approximately," etc., may be used here to mean "at, close to, or almost at" or "within 0-5% of" or "within acceptable manufacturing tolerances," or logical combinations thereof. A component that is "configured" to perform a particular function is capable of performing that function without modifications, and not merely has the potential to perform that function after further modifications.In other words, if the described hardware is explicitly configured to perform the specified function, it is specifically selected, created, implemented, used, programmed and / or designed to perform the specified function.

[0023] Embodiments of the present description may be described herein in the form of functional and / or logical block components and various processing steps. Such block components may be implemented by a number of hardware, software, and / or firmware components configured to perform the specified functions. For example, in one embodiment of the present description, various integrated circuit components may be used, such as memory elements, digital signal processing elements, logic elements, lookup tables, or the like, which, under the control of one or more microprocessors or other control units, can perform a variety of functions.Furthermore, the person skilled in the art will recognize that embodiments of the present description can be used in conjunction with a number of systems and that the systems described here are merely exemplary embodiments of the present description.

[0024] For the sake of brevity, techniques for signal processing, data fusion, signaling, control, and other functional aspects of the systems (and the individual operating components of the systems) are not described in detail herein. Furthermore, the connecting lines shown in the various figures are intended to represent exemplary functional relationships and / or physical couplings between the different elements. It should be noted that alternative or additional functional relationships or physical connections may exist in an embodiment of this description.

[0025] As in Fig. As shown in Figure 1, the vehicle 10 generally comprises a chassis 12, a body 14, and front and rear wheels 17. The body 14 is arranged on the chassis 12 and essentially encloses components of the vehicle 10. The body 14 and the chassis 12 can together form a frame. The wheels 17 are each rotatably connected to the chassis 12 near a corner of the body 14.

[0026] In various embodiments, vehicle 10 can be an autonomous vehicle. For example, vehicle 10 is a vehicle that is automatically controlled to transport passengers from one place to another. In the embodiment shown, vehicle 10 is depicted as a pickup truck, but it should be understood that other vehicles, including sport utility vehicles (SUVs), motorhomes (RVs), etc., can also be used.

[0027] The vehicle 10 is part of a vehicle system 9. The vehicle system 9 also includes a trailer 11 attached to the vehicle 10. The trailer 11 comprises one or more trailer axles 13, each having trailer wheels 15 for supporting the trailer 11.

[0028] As shown, the vehicle 10 generally comprises a drive system 20, a transmission system 22, a steering system 24, a braking system 26, a sensor system 28, an actuator system 30, at least one data storage device 32, at least one control unit 34, and a communication system 36. The drive system 20 may, in various embodiments, include an electric machine, such as a traction motor and / or a fuel cell drive system. The vehicle 10 further comprises a battery (or battery pack) 21, which is electrically connected to the drive system 20. Accordingly, the battery pack 21 is configured to store electrical energy and supply the drive system 20 with electrical energy. The drive system 20 may also include an internal combustion engine.The transmission system 22 is configured to transmit the power of the drive system 20 to the wheels 17 of the vehicle 10 according to the selectable speed ratios. According to various embodiments, the transmission system 22 may comprise a continuously variable automatic transmission, a stepped transmission, or another suitable transmission. The braking system 26 is configured to transmit a braking torque to the wheels 17 of the vehicle 10. In various embodiments, the braking system 26 may comprise friction brakes, brake-by-wire systems, a regenerative braking system such as an electric motor, and / or other suitable braking systems. The steering system 24 influences the position of the wheels 17 of the vehicle 10. Although a steering wheel is shown for illustrative purposes, the steering system 24 may not include a steering wheel in some embodiments considered within the scope of this description.

[0029] The wheels 17 of the vehicle 10 are supported by a front axle 19F and a rear axle 19R. The front axle 19F and rear axle 19R are separated from each other by a distance D1, and the rear axle 19R is separated from a front axle of the trailer 11 by a distance D2, and the front and rear trailer axles 13 are separated from each other by a distance D3.

[0030] The sensor system 28 includes one or more sensors 40 (i.e., devices) that detect observable conditions of the external environment and / or the internal environment of the vehicle 10. The sensors 40 communicate with the controller 34 and may include, among other things, one or more radars, one or more lidar (light detection and ranging) sensors, one or more ground penetrating radar (GPR) sensors, one or more GPS (global positioning system) devices, one or more cameras (e.g., one or more optical cameras and / or thermal imaging cameras, such as a rear camera and / or a front camera), a brake pedal position sensor, an accelerator pedal position sensor, a steering angle sensor, a speed sensor, a wheel speed sensor, ride height sensors, a steering angle sensor, ultrasonic sensors, one or more inertial measurement units (IMUs), a trailer connection status sensor, and / or other sensors.The trailer connection status sensor can determine the status of a trailer connection 31, e.g., an electrical connection, between the vehicle 10 and the trailer 9. The status of the trailer connection 31 can be used to determine the presence of the trailer 9.

[0031] The sensor system 28 comprises one or more GPS transmitters / receivers configured to acquire and monitor route data (i.e., route information). The GPS device is configured to communicate with a GPS to locate the position of the vehicle 10 on the globe. The GPS device communicates electronically with the controller 34. Since the sensor system 28 provides data to the controller 34, the sensor system 28 and its sensors 40 are considered information sources (or simply sources).

[0032] The actuator system 30 comprises one or more actuator devices 42 that control one or more vehicle functions, such as, but not limited to, the drive system 20, the transmission system 22, the steering system 24, and the braking system 26. In various embodiments, the vehicle features may also include interior and / or exterior features of the vehicle, such as doors, a trunk, and cabin features like air conditioning, music, lighting, etc. (not numbered). Examples of actuator devices 42 include an accelerator pedal, a brake pedal, etc.

[0033] The controller 34 comprises at least one processor 44 and a non-volatile, computer-readable memory device or medium 46. The processor 44 may be a custom or commercially available processor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processor among several processors connected to the controller 34, a semiconductor-based microprocessor (in the form of a microchip or chipset), a microprocessor, a combination thereof, or, more generally, an instruction-executing device. The computer-readable memory devices or media 46 may include volatile and non-volatile memory, such as read-only memory (ROM), random-access memory (RAM), and keep-alive memory (KAM). KAM is persistent or non-volatile memory that can be used to store various operating variables while the processor 44 is powered off.The computer-readable storage device or storage media 46 can be implemented using a variety of other storage devices such as PROMs (programmable read-only memory), EPROMs (electrically erasable PROMs), EEPROMs (electrically erasable PROMs), flash memory, or other electrical, magnetic, optical, or combined storage devices capable of storing data, some of which are executable instructions used by the controller 34 in controlling the vehicle 10.

[0034] The instructions can include one or more separate programs, each containing an ordered list of executable instructions for implementing logical functions. When executed by the processor 44, the instructions receive and process signals from the sensor system 28, perform logic, calculations, procedures, and / or algorithms for the automatic control of the vehicle 10 components, and generate control signals for the actuator system 30 to automatically control the vehicle 10 components based on the logic, calculations, procedures, and / or algorithms. Although in Fig. 1 where a single controller 34 is shown, embodiments of the vehicle 10 may include a number of controllers 34 which communicate and cooperate via a suitable communication medium or a combination of communication media to process the sensor signals, perform logic, calculations, procedures and / or algorithms and generate control signals to automatically control features of the vehicle 10.

[0035] The vehicle 10 has a human-machine interface (HMI) 23, which may be a screen in the center console or a driver information center. The HMI 23 interacts with a user to display information and receive confirmation, activation, delete commands, etc. The HMI 23 can be configured as an alarm device, for example, as a speaker to emit a sound, as haptic feedback in a vehicle seat or other object, as a visual display, or as another device suitable for conveying a notification to the driver of the vehicle 10. The HMI 23 communicates electronically with the controller 34 and is configured to receive input from a user (e.g., the driver). Accordingly, the controller 34 is configured to receive user input via the HMI 23.The human-machine interface 23 includes a display configured to show information to the user (e.g., the driver or passenger) and may include one or more speakers to transmit an audible message to the driver.

[0036] Fig. Figure 2 shows a flowchart of a procedure 100 for determining the number of trailer axles and the axle position of the trailer relative to the vehicle 10. In block 102, the procedure 100 receives vehicle operating characteristics and signals from the sensors 40 on the vehicle 10. In one example, the operating characteristics of the vehicle are transmitted as CAN messages via a CAN bus (Controller Area Network).The CAN messages contain vehicle-specific information, which may include suspension height at each corner of the vehicle 10, wheel-to-body offset, vehicle speed 10, vehicle acceleration 10, wheel speed sensor signals at each wheel 17, force at axles 19F and 19R, wheel torques at each wheel 17, inclination of a road surface, steering angle of the vehicle 10, trailer connection status signal with the vehicle 10, output from IMUs of the vehicle 10, ultrasonic sensor signals, camera signals, lidar signals, radar signals, relative time of occurrence of the above vehicle-specific information, etc.

[0037] The vehicle operating characteristics from the CAN messages are first analyzed in block 104 and stored in block 106, e.g., in the media 46 of vehicle 10. The vehicle operating characteristics stored in block 106 are used in block 110 to determine whether vehicle 10 has detected an enabling excitation, and in block 108 to determine whether vehicle 10 has encountered a road surface irregularity. The irregularity could be a bump in the road surface, such as a dip, a pothole, or any other change in the road surface.

[0038] In block 108, procedure 100 determines, based on the vehicle operating characteristics stored in block 106 from block 102, whether the vehicle 10 has encountered a bump. In one example, procedure 100 determines whether the vehicle 10 has encountered a bump by using the ride height sensor to monitor changes in the ride height of the front and rear axles of the vehicle 10. However, procedure 100 can also use other vehicle operating characteristics from sensors 40 or multiple operating characteristics of the vehicle to serve as a check for bump detection.

[0039] Fig. Figure 3 is a graphical representation 200 of the vehicle's ride height, as detected by at least one of the ride height sensors that are part of the sensor system 28. In the example shown, the graphical representation 200 defines time (t) along the x-axis and the vehicle height 202 along the y-axis with a line 204 representing changes in vehicle height over time (t). In the example shown, the changes in vehicle height are measured for a single rear wheel 17; however, the changes in vehicle height can also be measured for one or more of the other wheels 17 of the vehicle 10. In the example shown, the line 204 contains several peaks 206 that represent a change in the suspension direction corresponding to a time (t). The enlarged area 210 indicates a possible area representing the impact of the trailer 11 on the bump and the force transmission via the trailer hitch 29 to the vehicle 10.

[0040] As an alternative to measuring the vehicle's ride height, the graphical representation 200 can contain information from sensors 40 such as the wheel speed sensor, one of the IMUs, ultrasonic sensors, cameras, lidars or from another sensor 40 on the vehicle 10 that is capable of detecting an encounter of the vehicle 10 with the bump and an interaction of the trailer 11 with the vehicle 10 while the trailer 11 hits the bump.

[0041] Fig. 4A is a graphical representation of 300 of a derivative of the in Fig. The vehicle height shown in Figure 3 is derived from the graph. The derivative represents the rate of change of the vehicle height. The graph 300 defines time (t) along the x-axis and a rate of change 302 of the vehicle height along the y-axis with a line 304. In the example shown, the rate of change, represented by an initial peak 306, can indicate the rate of change of the vehicle height corresponding to the impact of a bump in the road.

[0042] An enlarged area 310 in Fig. 4A represents a time interval (t) during which the vehicle's ride height sensor has detected an interaction between the trailer 11, which encounters the bump, and the transmission of this encounter to the vehicle 10 via the coupling assembly 29. While the coupling assembly 29 in the example of Fig. Although 1 is shown as a bumper coupling, other coupling connections, such as a fifth wheel coupling or a gooseneck coupling, may be used within the scope of this description.

[0043] To establish the enabling excitation for the vehicle, the procedure 100 analyzes a series of vehicle operating characteristics from the sensors 40. The enabling excitation ensures that the vehicle 10 is operated in a manner that reduces the error in the calculations for determining the number and position of the trailer axles, as described below. In particular, the enabling excitation can ensure that the vehicle 10 and the trailer 11 do not move laterally and that the coupling angle between the vehicle 10 and the trailer 11 is zero or within a predetermined range, including or close to zero.In one example, the enabling excitation for the vehicle 10 can be at least one of the following: a yaw acceleration less than a predetermined threshold; a difference in wheel speed between the left and right wheels 17 on a common axle 19 within a predetermined threshold range; a steering wheel angle less than a predetermined threshold; or a speed greater than a predetermined threshold to ensure sufficient excitation of the system upon encountering the road obstacle, e.g., a bump. The speed measured by the sensors 40 can also vary.

[0044] Once procedure 100 has determined that a road bump was detected in block 108 and confirmed in block 110 that vehicle 10 generated the enabling excitation, procedure 100 proceeds to block 112 to perform a further analysis of the vehicle operating characteristics. In the example shown, a time-based amplitude-phase shape is applied to the data in Fig. The rate of change of the vehicle height shown in Figure 4A was applied to generate a rate-of-change-based amplitude with EQ 1 below (e.g., a Fourier series analysis). Furthermore, other time-based methods can also be used, such as autocorrelation of the vehicle height with itself or cross-correlation with another signal, to determine the temporal position of the trailer's interaction with the road undulation relative to the vehicle's interaction with the road undulation and to estimate the position of the trailer axle. sN(x)=A02+∑n=1NAn∗cos(2πPnx−φn)

[0045] Fig. 4B is a graphical representation 400 of the amplitude-phase form of the Fourier series, applied to the rate of change from Fig. 4A. The graphical representation is performed over time (t) along the x-axis, with an output 402 shown along the y-axis. The enlarged view 410 illustrates a maximum amplitude 406 of a line 404. Taking into account the frequency and the wavelength, the position of each of the follower axes 13 in block 114 can be extracted.

[0046] In block 114, method 100 uses a vehicle longitudinal model, such as the one shown in EQ. 2, to determine the position of each of the trailer axles 13. ϕAx1^=Z

[0047] In EQ. 2 above, Z is an output signal and ϕ is a regression signal. Procedure 100 performs an estimation procedure by applying a recursive least squares method, as shown in EQS. 3-5 below. x^k+1=x^k+Kk+1(Zk+1−ϕk+1x^k) Kk+1=Pkϕk+1λ+ϕk+1Pkϕk+1' Pk+1=(1−Kk+1ϕk+1)pk / λ

[0048] Method 100 can then output a position of the trailer axle, as shown in graphic representation 450. Fig. 5 is shown by analyzing a relative time difference between the time the vehicle 10 struck the bump and the time the trailer 11 struck the bump. In graph 450, time (t) is shown along the x-axis and the length of the trailer axle 454 is shown along the y-axis. In the example shown, the length of the trailer axle is relative to a point on the vehicle 10 and represents the position of a single trailer axle 13; however, method 100 can also be used to determine the position of multiple trailer axles 13. Line 456 shows the actual trailer axle length relative to the vehicle 10 and line 458 shows the estimated trailer axle length relative to the vehicle 10, based on method 100 above. As in Fig. As shown in Figure 1, the trailer axle length can be represented as a combination of lengths D1, D2 or D3, depending on the axle to be located and the relative position on the vehicle 10.

[0049] A feature of determining the position of the axles of trailer 9 relative to vehicle 10 is the unambiguous identification of the trailer 9 coupled to vehicle 10. Therefore, method 100 can function independently of the fact that the control unit 34 detects the presence of trailer 9 via the trailer connection 31. Thus, method 100 provides redundant confirmation of the presence of trailer 9 coupled to vehicle 10 in the event of a malfunction of the trailer connection 31.

[0050] Fig. Figure 6 shows another flowchart of a procedure 600 for determining the number of trailer axles and the axle position of the trailer relative to the vehicle 10. In the example shown, the procedure 600 receives a velocity of a left front wheel. VxFL and a speed of a right front wheel VxFR in block 602 and determines whether the acceleration of one of the two front wheels has exceeded a predetermined threshold acceleration. Similarly, method 600 receives a speed reading from a left rear wheel. VxRL and a speed of the right rear wheel VxRR in block 604 and determines whether an acceleration in one of the rear wheels has exceeded a predetermined threshold acceleration. If one of the front wheels experiences an acceleration that exceeds the predetermined threshold, procedure 600 proceeds to block 608.

[0051] In block 608, procedure 600 performs a road undulation detection. The start of a velocity integral is triggered in block 610 when the acceleration of one of the front wheels exceeds the threshold value specified in block 602. Fig. Figure 7 shows a graphical representation 700 with line 706 of a longitudinal acceleration a x along the y-axis 704 from one or both front wheels of the vehicle 10 over a time interval (t) along the x-axis 702. How the time window 708 in Fig. Figure 7 shows that at least one of the front wheels of vehicle 10 has hit a bump in the ground sufficient to trigger the velocity integral in block 612.

[0052] The velocity integral stops in block 614 when the acceleration of one or both rear wheels exceeds the specified threshold acceleration. Fig. Figure 8 shows a graphical representation 720 with line 726 of a longitudinal acceleration a xalong the y-axis 724 from one or both rear wheels of vehicle 10 over a time interval (t) along the x-axis 722. How the time window 728 in Fig. Figure 8 shows that at least one of the rear wheels of vehicle 10 has encountered a bump in the road surface sufficient to stop the velocity integral at block 614. Once the velocity integral has stopped, block 610 gives an estimated wheelbase length WB. est from which is used in block 616 to verify the road surface undulation.

[0053] The verification of the road undulations carried out in block 616 compares the estimated wheelbase length WB. est with a wheelbase calibration value from block 606. The wheelbase calibration value represents a measured or specified wheelbase length for vehicle 10. If the estimated wheelbase length WB estIf the difference is within a predetermined range or percentage of the wheelbase calibration value, e.g., if the difference is less than or equal to 5%, then procedure 600 has determined that vehicle 10 has hit a bump and proceeds to block 620. If the estimated length WB est If the value is not within the predetermined range or percentage, procedure 600 continues with block 618 and stops determining the number and position of the trailer axles, as the wheelbase comparison has not confirmed that vehicle 10 hit a bump.

[0054] In block 620, procedure 600 begins by determining the number of trailer axles and the axle position of the trailer relative to the towing vehicle 10 by starting an additional velocity integral in block 634. The start of the velocity integral in block 634 coincides with a time at which block 622 detects that one of the rear wheels of the vehicle 10 has experienced a sudden acceleration that has exceeded the predetermined threshold acceleration.

[0055] Once the velocity integral in block 636 has started, procedure 600 in blocks 638 and 640 begins determining the number of trailer axles and the axle position relative to vehicle 10. Block 638 receives additional information about vehicle 9 from block 624 from at least one of the sensors 40 on vehicle 9, such as an IMU. In the example shown, the additional vehicle-related information includes a longitudinal jerk ȧ xof the vehicle in block 626, a yaw acceleration ω̇ z of vehicle 9 in block 628 and a pitch acceleration ω̇ y of vehicle 9 in block 630. If at least one from the longitudinal jerk ȧ x , the yaw acceleration ω̇ z or the pitch acceleration ω̇ y If a corresponding predetermined threshold acceleration is exceeded, block 624 sends a message to block 638 that at least one of the trailer axles 13 of the trailer 11 has hit a bump in the ground. Fig. Figure 9 shows a graphic representation of the longitudinal pressure 740. x , of vehicle 9, which is used by block 626. In the example shown, the graphical representation 740 includes the time (t) along an x-axis 742 and the jerk ȧ. x, along the y-axis 744. A time window 748, which contains the line 746, represents when trailer 9 hit the bump.

[0056] Block 638 can be used to record the time of occurrence of the bump. If trailer 11 continues to experience one of the aforementioned accelerations / jerks exceeding the relevant threshold, procedure 600 can indicate that trailer 11 has multiple axles and that a following axle 13 of trailer 11 has experienced the bump.

[0057] Fig. Figure 10 is a graphical representation 800 of the identification of trailer axles with a line 806 where the relative time (t) is along the x-axis 802 and the number of identified axles is along the y-axis 804. In the Fig. In the example shown, each step in line 806 indicates a relative time at which block 624 identified trailer 11, which experienced one of the accelerations that exceeded the specified threshold.

[0058] Fig.Figure 11 further shows a graphical representation 850 for identifying the longitudinal positions of the trailer axles 13, with lines 856 and 858 representing the relative time (t) along the x-axis 852 and the longitudinal position along the y-axis 854. Line 856 denotes a first relative time for the velocity integral to identify the position of the first trailer axle 13, and line 858 denotes a second relative time for the velocity integral to identify the second trailer axle 13. Lines 860 and 862 correspond to the actual positions of the trailer axles 13 compared to the estimated positions of the trailer axles.

[0059] Method 600 also analyzes the longitudinal pressure ȧ x , the yaw acceleration ω̇ z or the pitch acceleration ω̇ yin block 632 to determine a reduction in vibration amplitude. A reduction in vibration amplitude in at least one of the parameters longitudinal stress ȧ x , the yaw acceleration ω̇ z or the pitch acceleration ω̇ y This can indicate that no further trailer axles of trailer 11 can be identified and that the velocity integral from block 638 should be terminated. Block 620 can then output the number and position of the trailer axles, based on the relative times from block 638, which receives the relative times at which at least one of the quantities longitudinal jerk ȧ x , the yaw acceleration ω̇ z or the pitch acceleration ω̇ y The corresponding predetermined threshold has been exceeded, and there is a reduction in the amplitude of one of the accelerations / jerks. The longitudinal jerk is a derivative of the vehicle's acceleration.

[0060] Based on the number of trailer axles and their axle positions, determined either by Procedure 100 or Procedure 600 above, this information can be used as input to automatically adjust an automatic trailer brake booster modifier. Furthermore, if multiple axles are identified, the effective wheelbase of the trailer can be estimated based on the average of each axle position relative to the vehicle.

[0061] Furthermore, procedures 100 and 600 can continuously recalculate the number of trailer axles and the axle position of the trailer to detect a change in the operating status of the trailer 11. For example, if procedures 100 or 600 detect a change in the number of trailer axles or the axle position above a predetermined threshold, they can determine that a status change of the trailer 11 has occurred. A status change might indicate, for example, that a primary coupling between the vehicle 10 and the trailer 11 has detached or that the hitch requires further adjustments, such as a change in the mounting height of the vehicle 10 to level the trailer 11.

[0062] The terms "a" and "an" do not imply a quantitative restriction, but rather denote the presence of at least one of the elements mentioned. The term "or" means "and / or" unless the context clearly indicates otherwise. When the entire description refers to "an aspect," this means that a particular element (e.g., a feature, a structure, a step, or a property) described in connection with that aspect is contained in at least one of the aspects described here and may or may not be present in other aspects. Furthermore, the described elements can be combined appropriately across the various aspects.

[0063] When an element such as a layer, film, area, or substrate is described as being "on" another element, it may be located directly on top of that element, or there may be intermediate elements. Conversely, when an element is described as being "directly on" another element, there are no intermediate elements.

[0064] Unless otherwise stated herein, verification standards are the latest standard in force on the filing date of this application or, if priority is claimed, the filing date of the earliest priority application in which the verification standard appears.

[0065] Unless otherwise defined, the technical and scientific terms used herein have the same meanings as they are commonly understood by a person skilled in the field to which this description relates.

[0066] Although the above disclosure has been described with reference to exemplary embodiments, the person skilled in the art understands that various modifications can be made and equivalent elements can be replaced by others without departing from the scope of the disclosure. Furthermore, many modifications can be made to adapt a particular situation or material to the teachings of the description without infringing its scope. Therefore, the present description is not intended to be limited to the particular embodiments mentioned, but also to include embodiments that fall within the scope of the disclosure.

Claims

[1] Method (100) for determining a trailer axle number and axle position of a trailer (11) relative to a vehicle (10), the method comprising: Receiving (102) a plurality of vehicle operating characteristics from at least one sensor (40) on the vehicle (10); Determining (108) whether the vehicle (10) has encountered a bump in a roadway based on at least one of the plurality of vehicle operating characteristics; Determining whether at least one trailer axle (13) has hit the bump; and Analyzing a relative time difference between the time at which the vehicle (10) hit the bump and the time at which the at least one trailer axle (13) hit the bump to determine a trailer axle number and to estimate a position of the at least one trailer axle (13) relative to the vehicle (10). [2] The method of claim 1, including determining an enabling excitation of the vehicle (10) when the vehicle (10) encounters the bump, wherein determining the enabling excitation comprises identifying at least one of a steering angle of the vehicle (10) that is within a predetermined range, a speed of the vehicle (10) that is greater than a predetermined speed, or a difference in wheel speed between laterally spaced wheels of the vehicle (10) that is less than a predetermined value. [3] The method of claim 1, including confirming the presence of the trailer (11) coupled to the vehicle (10) when estimating the position of the at least one trailer axle (13) relative to the vehicle (10). [4] The method of claim 1, wherein the at least one sensor (40) comprises at least one of a ride height sensor, a wheel speed sensor, or an inertial measurement unit located on the vehicle (10), and wherein determining whether the vehicle (10) has hit the bump is based on determining an amplitude of a rate of change of the at least one of the plurality of vehicle operating characteristics. [5] The method of claim 1, wherein the at least one sensor (40) is located on the vehicle (10) and wherein determining whether the at least one trailer axle (13) has hit the bump is based on determining an amplitude of a rate of change of the at least one of the plurality of vehicle operating characteristics within a time frame after the vehicle (10) has hit the bump. [6] The method of claim 5, including determining a status of the trailer (11) by determining whether the amplitude of the rate of change of the at least one vehicle operating characteristic is within a predetermined range. [7] A method according to claim 1, comprising: Receiving a second plurality of vehicle operating characteristics from the at least one sensor (40) on the vehicle (10); Determining whether the vehicle (10) has encountered a second bump in the roadway based on at least one of the second plurality of vehicle operating characteristics; Determining whether at least one trailer axle (13) has hit the bump; Analyzing a relative time difference between the time at which the vehicle (10) encountered the bump and the time at which the at least one trailer axle (13) encountered the bump to determine a second trailer axle number and to estimate a second position of the at least one trailer axle (13) relative to the vehicle (10); and Determining a change in the operating state of the trailer (11) if a difference between the second position of the at least one trailer axle (13) and the position of the at least one trailer axle (13) exceeds a predetermined threshold value. [8] The method of claim 1, wherein determining whether the vehicle (10) hit the bump comprises determining an estimated wheelbase length for the vehicle (10) based on a speed of the vehicle (10) and a relative time difference between the time a front wheel of the vehicle (10) hit the bump and the time a rear wheel of the vehicle (10) hit the bump. [9] The method of claim 8, wherein if the estimated wheelbase length is within a predetermined range of a predetermined wheelbase length for the vehicle (10), the vehicle (10) has hit the bump. [10] The method of claim 8, wherein determining the estimated wheelbase length comprises integrating a speed of the vehicle (10) starting when one of the two front wheels hits the bump until one of the two rear wheels hits the bump.

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