METHOD AND ARCHITECTURE FOR THE IDENTIFICATION AND CONTAMINATION OF POWER-HOP

Abstract

The procedure for identifying and mitigating power-hop includes receiving sensor data from a vehicle, such as wheel speed; determining a wheel pressure characteristic of the vehicle based on the wheel speed; determining a ride height of the vehicle; determining, based on the wheel pressure characteristics and the ride height of the vehicle, whether the vehicle is experiencing power-hop; and, in response to determining that the vehicle is experiencing power-hop, adjusting a torque of the vehicle to mitigate power-hop.

Description

INTRODUCTION

[0001] The present disclosure relates to an architecture and method for identifying and mitigating power hop.

[0002] This introduction sets out the content of the disclosure in general. The work of the presently named inventors, to the extent described in this introduction, as well as those aspects of the description which do not otherwise qualify as prior art at the time of filing, are neither expressly nor implicitly admitted as prior art against this disclosure.

[0003] Power hop, also known as wheel hop, is an adverse phenomenon that occurs in vehicle dynamics, particularly in high-performance vehicles, where excessive torque is transferred to the wheels, resulting in sudden and rapid vertical movement of the tires and suspension system, leading to a loss of traction and stability. When it comes to passenger safety and ride comfort in vehicles, it is desirable to identify and address power hop in real time. SUMMARY

[0004] The present disclosure describes a system and method for identifying and mitigating power hop in real time to enhance the overall driving experience and ensure a comfortable ride in the vehicle. A system including one or more computers may be configured to perform specific operations or actions based on software, firmware, hardware, or a combination thereof that has been installed on the system and that, during operation, causes the system to perform the actions. The one or more computer programs may be configured to perform specific operations or actions by including instructions that, when executed by computing devices, cause the devices to perform the actions. One general aspect includes a method for identifying and mitigating power hop.The method also includes receiving sensor data of a vehicle, the sensor data including wheel speed; determining a wheel pressure characteristic of the vehicle based on the wheel speed; determining a ride height of the vehicle; determining whether the vehicle is experiencing power hop based on the wheel pressure characteristics and the ride height of the vehicle; and, in response to determining that the vehicle is experiencing power hop, adjusting a torque of the vehicle to mitigate power hop. Further embodiments of this aspect include corresponding computer systems, devices, and computer programs recorded in one or more computer storage devices, each configured to perform the acts of the methods.

[0005] Implementations may include one or more of the following features. In the method, the wheel pressure characteristics include a wheel pressure amplitude and a wheel pressure duration, where the wheel pressure amplitude is the second derivative with respect to time of the wheel speed. The method may include determining whether an absolute value of a change in wheel pressure amplitude within a predetermined time period is greater than a predetermined amplitude threshold, and in response to determining that the absolute value of the change in wheel pressure amplitude within the predetermined time period is greater than the predetermined amplitude threshold, setting a wheel speed flag to on.The method may include determining whether a change in ride height of the vehicle within the predetermined time period is less than a predetermined ride height threshold, and in response to determining that the change in ride height of the vehicle within the predetermined time period is less than the predetermined ride height threshold, setting a ride height flag to on. The method may include determining whether an anti-lock braking system (ABS) of the vehicle is inactive. The method may include determining whether the derivative with respect to time of a throttle position is equal to or greater than zero.The method may include determining that the vehicle's ABS is inactive, determining that the throttle position time derivative is equal to or greater than zero, determining that the wheel speed flag is set to on, determining that the ride height flag is set to on; and setting a power hop flag on in response to (a) determining that the vehicle's ABS is inactive; (b) determining that the throttle position time derivative is equal to or greater than zero; (c) determining that the wheel speed flag is set to on; (d) determining that the ride height flag is set to on. The vehicle's torque is adjusted to contain power hop in response to the power hop flag being set to on. Implementations of the described techniques may include hardware, a method or process, or computer software on a computer-accessible medium.

[0006] The present disclosure also describes a vehicle including sensors and a controller in communication with the sensors. The sensors may include one or more wheel speed sensors and one or more ride height sensors. The controller is programmed to perform the method described above.

[0007] Further areas of applicability of the present disclosure will become apparent from the detailed description provided below. It should be understood that the detailed description and specific examples are for purposes of illustration only and are not intended to limit the scope of the disclosure.

[0008] The above-described features and advantages and other features and advantages of the presently disclosed system and method will be apparent from the detailed description, including the claims and exemplary embodiments, when taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] The present disclosure will be more fully understood from the detailed description and the accompanying drawings, in which: Fig. 1 is a block diagram showing an embodiment of a vehicle; Fig. 2 is a flowchart of a method for identifying and mitigating power hop; Fig. 3 is a flowchart of a method for determining wheel pressure characteristics; Fig. 4 is a flowchart of a method for determining the state of the wheel speed flag; Fig. 5 is a flowchart of a method for determining the ride height; Fig. 6 is a flowchart of a method for determining the state of the ride height flag; and Fig. 7 is a flowchart for checking the status of the anti-lock braking system and the throttle position. DETAILED DESCRIPTION

[0010] Reference will now be made in detail to some examples of the disclosure illustrated in the accompanying drawings. Where possible, the same or similar reference numerals are used throughout the drawings and the description to refer to the same or similar sections or steps.

[0011] With reference to Fig. 1, a vehicle 10 generally includes a chassis 12, a body 14, and front and rear wheels 17, and may be referred to as a vehicle system. In the illustrated embodiment, the vehicle 10 includes two front wheels 17a and two rear wheels 17b. The body 14 is disposed on the chassis 12 and substantially encloses components of the vehicle 10. The body 14 and the chassis 12 may together form a frame. The wheels 17 are each rotationally coupled to the chassis 12 near a respective corner of the body 14. The vehicle 10 includes a front axle 19 coupled to the front wheels 17a and a rear axle 25 coupled to the rear wheels 17b.

[0012] The vehicle 10 is an autonomous vehicle, and a control system 98 is incorporated into the vehicle 10. The system 98 may be referred to as the system or the system for controlling the steering system 24. The vehicle 10 is, for example, a vehicle that is automatically controlled to guide passengers from one location to another. The vehicle 10 is shown as a pickup truck in the illustrated embodiment, but it should be appreciated that other vehicles, including trucks, sedans, coupes, sport utility vehicles (SUVs), recreational vehicles (RVs), etc., may also be used. In one embodiment, the vehicle 10 may include a so-called level two, level three, level four, or level five driving automation system.A level four system indicates "high automation," which refers to the drive-mode-specific performance by an automated driving system of aspects of the dynamic driving task, even when a human driver does not appropriately respond to a request to intervene. A level five system indicates "full automation," which refers to the full-time performance by an automated driving system of aspects of the dynamic driving task under multiple road and environmental conditions that can be managed by a human driver. In Level 3 vehicles, the system 98 performs the entire dynamic driving task (DDT) within the range in which it is designed to do so. In Level 2 vehicles, systems provide steering, braking / acceleration assistance, lane centering, and adaptive cruise control.However, even when these systems are activated, the vehicle operator must be behind the wheel and constantly monitor the automated features.

[0013] As shown, the vehicle 10 generally includes a propulsion system 20, a transmission system 22, a steering system 24, an anti-lock braking system (ABS) 26, 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. The steering system 24 is an electromechanical steering system. The propulsion system 20, in various embodiments, may include an electric machine such as a traction motor and / or a fuel cell propulsion system. The vehicle 10 may further include a battery (or battery pack) 21 electrically connected to the propulsion system 20. Accordingly, the battery 21 is configured to store electrical energy and to provide electrical energy to the propulsion system 20. In certain embodiments, the propulsion system 20 may include an internal combustion engine.The transmission system 22 is configured to transfer power from the propulsion system 20 to the vehicle wheels 17 according to selectable speed ratios. According to various embodiments, the transmission system 22 may include a stepped-ratio automatic transmission, a continuously variable transmission, or other suitable transmission. The ABS 26 is configured to impart braking torque to the vehicle wheels 17. The ABS 26, in various embodiments, may include friction braking, electromechanical braking, a regenerative braking system such as an electric machine, and / or other suitable braking systems. The steering system 24 influences the position of the vehicle wheels 17 and may include a steering wheel 33. While illustrated as including a steering wheel 33 for illustrative purposes, in some embodiments contemplated within the scope of the present disclosure, the steering system 24 may not include a steering wheel 33.

[0014] The sensor system 28 includes one or more sensors 40 (i.e., sensing devices) that sense observable conditions of the external environment and / or the internal environment of the vehicle 10. The sensors 40 are in communication with the controller 34 and may include one or more steering wheel sensors 45, one or more radars, one or more light detection and ranging sensors (lidar sensors), one or more proximity sensors, one or more wheel speed sensors, one or more odometers, one or more ground-penetrating radar (GPR) sensors, one or more steering angle sensors, one or more global navigation satellite system (GNSS) transceivers (e.g.,The sensor system 28 may include, but is not limited to, one or more global positioning system (GPS) transceivers, one or more tire pressure sensors, one or more throttle position sensors, one or more cameras 41 (e.g., eye tracking devices), one or more gyroscopes, one or more accelerometers, one or more inclinometers, one or more speed sensors, one or more ultrasonic sensors, one or more inertial measurement units (IMUs), one or more night vision devices, thermal imaging sensors, and / or other sensors. Each sensor 40 is configured to generate a signal indicative of the sensed observable conditions of the external environment and / or the internal environment of the vehicle 10. Because 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).The vehicle 10 and / or the system 98 does not include any light sensors that can detect light in the vehicle 10.

[0015] The actuator system 30 includes one or more actuators 42 that control one or more vehicle features, such as, but not limited to, the propulsion system 20, the transmission system 22, the steering system 24, and the ABS 26. In various embodiments, the vehicle features may further include interior and / or exterior vehicle features, such as, but not limited to, doors, a trunk, and cabin features such as air, music, lighting, etc. The actuator 42 may include a throttle valve.

[0016] The data storage device 32 stores data for use in automatically controlling the vehicle 10. In various embodiments, the data storage device 32 stores defined maps of the navigable environment. According to various embodiments, the defined maps may be predefined by and obtained from a remote system. For example, the defined maps may be compiled by the remote system and communicated to the vehicle 10 (wirelessly and / or in a wired manner) and stored in the data storage device 32. The data storage device 32 may be part of the controller 34, separate from the controller 34, or part of the controller 34 and part of a separate system.

[0017] The vehicle 10 may further include one or more airbags 35 in communication with the controller 34 or another controller of the vehicle 10. The airbag 35 includes an inflatable bladder and is configured to transition between a stowed configuration and a deployed configuration to cushion the effects of an external force applied to the vehicle 10. The sensors 40 may include an airbag sensor, such as an IMU, configured to detect an external force and generate a signal indicative of the magnitude of such an external force. The controller 34 is configured to command the airbag 35 to deploy based on the signal from one or more sensors 40, such as the airbag sensor. Accordingly, the controller 34 is configured to determine when the airbag 35 has deployed.

[0018] The controller 34 includes at least one processor 44 and a non-transitory computer-readable storage device or storage medium 46. The processor 44 may be a custom-built or off-the-shelf processor, a central processing unit (CPU), a graphics processing unit (GPU), an auxiliary processor among multiple processors associated with the controller 34, a semiconductor-based microprocessor (in the form of a microchip or chipset), a macroprocessor, a combination thereof, or generally a device for executing instructions. The computer-readable storage device or storage medium 46 may include, for example, volatile and non-volatile memory in read-only memory (ROM), random access memory (RAM), and retained memory (RAM).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 medium 46 can be implemented using a number of storage devices such as PROMs (programmable read-only memories), EPROMs (electrical PROMs), EEPROMs (electrically erasable PROMs), flash memory, or other electrical, magnetic, optical, or combination storage devices that can store data, some of which represents executable instructions used by the controller 34 in controlling the vehicle 10. The controller 34 of the vehicle 10 may be referred to as a vehicle controller and may be programmed to implement a method 200 (. Fig. 2), which is described in detail below.

[0019] The instructions may include one or more separate programs, each comprising an ordered list of executable instructions for implementing logical functions. The instructions, when executed by the processor 44, receive and process signals from the sensor system 28, perform logic, calculations, methods, and / or algorithms to automatically control the components of the vehicle 10, and generate control signals to the actuator system 30 to automatically control the components of the vehicle 10 based on the logic, calculations, methods, and / or algorithms. Although in Fig. 1, embodiments of the vehicle 10 may include multiple controllers 34 that communicate via a suitable communication medium or combination of communication media and that cooperate to process the sensor signals, perform logic, calculations, methods, and / or algorithms, and generate control signals to automatically control features of the vehicle 10. In various embodiments, one or more commands of the controller 34 are embodied in the control system 98.

[0020] The vehicle 10 includes a user interface 23, which may be a touchscreen in the instrument panel. The user interface 23 may include, but is not limited to, an alarm such as one or more speakers 27 for providing an audible sound, haptic feedback in a vehicle seat or other object, one or more display devices 29, one or more microphones 31, and / or other devices suitable for providing notification to the vehicle user of the vehicle 10. The user interface 23 is in electronic communication with the controller 34 and is configured to receive inputs from a vehicle occupant 11 (e.g., a vehicle driver or a vehicle passenger). For example, the user interface 23 may include a touchscreen and / or buttons configured to receive inputs from a vehicle occupant 11.Accordingly, the controller 34 is configured to receive inputs from the user via the user interface 23. The vehicle 10 may include one or more display devices 29 configured to display information about the vehicle occupant 11 (e.g., the vehicle operator or the passenger) and may be a head-up display (HUD).

[0021] The communication system 36 is in communication with the controller 34 and is configured to wirelessly communicate information to and from other remote vehicles 48, such as, but not limited to, other vehicles ("V2V" communication), infrastructure ("V2I" communication), remote systems at a remote call center (e.g., ON-STAR from GENERAL MOTORS), and / or personal electronic devices such as a cellular phone. In the present disclosure, the term "remote vehicle" means a vehicle, such as a passenger car, that is configured to send one or more signals to the vehicle 10 while not physically connected to the vehicle 10. In certain embodiments, the communication system 36 is a wireless communication system configured to communicate via a wireless local area network (WLAN) using IEEE 802.11 standards or using cellular data communication.However, additional or alternative communication methods, such as a dedicated short-range communication (DSRC) channel, are also considered within the scope of the present disclosure. DSRC channels refer to unidirectional or bidirectional short- to medium-range wireless communication channels specifically designed for use in motor vehicles and a corresponding set of protocols and standards. Accordingly, the communication system 36 may include one or more antennas and / or communication transceivers 37 for receiving and / or transmitting signals such as cooperative sensing messages (CSMs). The communication transceivers 37 may be considered sensors 40. The communication system 36 is configured to wirelessly communicate information between the vehicle 10 and another vehicle.Furthermore, the communication system 36 is configured to wirelessly communicate information between the vehicle 10 and infrastructure or other vehicles.

[0022] Fig. Figure 2 shows a flowchart of a method for identifying and mitigating power hop. Method 200 detects and mitigates power hop. Power hop, also known as wheel hop, is an oscillating phenomenon typically experienced in high-performance vehicles during hard acceleration. Power hop can negatively impact the driveline system. In addition to accurately detecting power hop, method 200 implements an effective mitigation strategy. Depending on the sensor set available in the vehicle, method 200 identifies power hop based on wheel speed jerk characteristics, relative wheel-to-body motion (i.e., ride height motion), throttle position changes, and ABS interaction.Method 200 also includes a data-driven method that uses IMU sensor information when both the wheel speed sensors and ride height sensors are unavailable to identify power hop. Once power hop is identified, a speed-dependent control strategy is proposed to mitigate the severity of the event. Prioritization and arbitration of control actions are also considered.

[0023] With continued reference to Fig. 2, method 200 begins in block 202. Block 202 includes receiving sensor data from sensors 40, such as the wheel speed sensors, the IMU, and the ride height sensors. Therefore, the sensor data may include the wheel speed, ride height, and lateral and / or longitudinal acceleration of the vehicle 10. In block 202, the controller determines the wheel pressure characteristics of the vehicle 10 based on the wheel speed. The wheel pressure characteristics include the wheel pressure amplitude and the wheel pressure duration.

[0024] Fig. 3 shows a flowchart of a method 300 for performing at least a portion of block 202. The method 300 begins in block 302. The method 300 then proceeds to block 304. In block 304, the controller 34 sets the wheel pressure amplitude and continuously monitors it at predetermined time intervals. Each time interval comprises a predetermined period of time. The controller 34 calculates the second derivative of the wheel speed of the driven wheels 17 with respect to time to determine the wheel pressure amplitude. The method 300 then proceeds to block 306. In block 306, the controller 34 retrieves the output parameters. The output parameters are the predetermined amplitude threshold, the wheel speed flag set to off, and the predetermined wheel pressure duration threshold. The method 300 then proceeds to block 308.Block 308 includes looping the wheel pressure and evaluating several predefined, calibratable thresholds to identify the beginning and end of a power hop event. Method 200 then proceeds to block 308. Block 310 includes an analysis of the wheel pressure characteristics, described below. After block 310, method 300 returns to block 304.

[0025] Fig. 4 shows a method 400 for analyzing wheel pressure characteristics, which is performed in block 310 of method 300. Method 400 begins in block 402. Block 402 includes determining the absolute value of a change in wheel pressure amplitude within a predetermined time period. Further, in block 402, the controller determines whether the absolute value of a change in wheel pressure amplitude within the predetermined time period is greater than the predetermined amplitude threshold. If the absolute value of a change in wheel pressure amplitude within the predetermined time period is greater than the predetermined amplitude threshold, method 400 continues to block 404. In block 404, controller 34 determines whether the wheel speed flag is set to on. If the wheel speed flag is set to on, method 400 continues to block 406. In block 406, the flag counter is incremented by one. Method 400 then proceeds to block 408.In block 408, the controller 34 sets the wheel speed flag to on at the current time. Method 400 then continues to block 410. In block 410, the controller 34 outputs that the wheel speed flag is set to on.

[0026] If it is determined in block 402 that the absolute value of the change in wheel pressure amplitude within the predetermined time period is not greater than the predetermined amplitude threshold, the method 400 proceeds to block 412. In block 412, the controller 34 determines whether the wheel speed flag is set to on and the predetermined time threshold has expired. If the wheel speed flag is set to on and the wheel pressure duration threshold has expired, the method 400 proceeds to block 414. In block 414, the controller 34 sets the wheel speed flag to off. The method 400 then proceeds to block 416, and the controller 34 resets the counter.

[0027] If it is determined in block 412 that either the wheel speed flag is set to off or the predetermined time threshold has expired, the method 400 continues to block 418. In block 418, the wheel speed flag remains in its state. After block 418, the method 400 continues to block 410.

[0028] If it is determined in block 404 that the wheel speed flag is in the off state, the method 400 proceeds to block 420. In block 420, the wheel speed flag is set to on. The method 400 then proceeds to block 422. In block 422, the controller 34 outputs that the wheel speed flag is set to on.

[0029] With reference to Fig. 2, after executing block 202, method 200 proceeds to block 204. In block 204, controller 34 analyzes the ride height of vehicle 10 and determines whether the ride height flag should be set on or off.

[0030] Fig. 5 shows a method 500 for analyzing the ride height of the vehicle 10, which was explained above with reference to block 204. The method 500 begins in block 502. The method 500 then proceeds to block 504. In block 504, the controller 34 determines the ride height of the vehicle 10 at various time intervals using the sensor data from the ride height sensors. Each time interval comprises a predetermined period of time. Also in block 504, the controller 34 determines the longitudinal acceleration of the vehicle 10 at various time intervals using, for example, the sensor data from the IMU. The method 500 then proceeds to block 506. In block 506, the controller 34 retrieves the output parameters. The output parameters include a predetermined ride height threshold and a longitudinal acceleration threshold. The method 500 then proceeds to block 508.Block 508 involves looping the ride height and evaluating several predefined, calibratable thresholds at each time point. Method 500 then proceeds to block 510. In block 510, controller 34 analyzes the ride height to determine whether the ride height flag should be set on or off, as described below. Method 500 then returns to block 504.

[0031] Fig. 6 shows a method 600 for analyzing the ride height of the vehicle 10, which is performed in block 510 of the method 500. The method 600 begins in block 602. Block 602 includes determining whether a change in the longitudinal acceleration of the vehicle 10 within the predetermined time period is greater than the predetermined acceleration threshold. If the change in the longitudinal acceleration of the vehicle 10 within the predetermined time period is greater than the predetermined acceleration threshold, the method 600 proceeds to block 604. In block 604, the controller 34 determines whether a change in the ride height of the vehicle 10 within the predetermined time period is less than the predetermined ride height threshold. If the change in the ride height of the vehicle 10 within the predetermined time period is less than the predetermined ride height threshold, the method 600 proceeds to block 606. In block 606 the ride height flag is set to On.If the change in ride height of the vehicle 10 within the predetermined time period is not less than the predetermined ride height threshold, the method 600 proceeds to block 608. In block 608, the ride height flag is set to off.

[0032] If it is determined at block 602 that the change in longitudinal acceleration of the vehicle 10 within the predetermined time period is not greater than the predetermined acceleration threshold, the method 600 proceeds to block 610. At block 610, the controller 34 determines whether the wheel speed flag is set to on. If the wheel speed flag is set to on, the method 600 proceeds to block 604. If the wheel speed flag is set to off, the method 600 proceeds to block 612. At block 612, the ride height flag is set to off.

[0033] With continued reference to Fig. 2, after executing block 204, method 200 proceeds to block 206. In block 206, the state of the ABS 26 and the throttle position are checked to determine whether the power hop flag is set on or off, as explained in detail below.

[0034] The Fig. 7 shows a flowchart of a method 700 for checking the state of the ABS 26 and the throttle position. The method 700 begins in blocks 702, 704, 706, and 708. Block 702 includes determining whether the ride height flag is set on. If the ride height sensors are unavailable, the ride height flag is set on. Block 704 includes determining whether the wheel speed flag is set on. Block 706 includes determining whether the state of the ABS 26 is inactive. In block 708, the controller 34 determines whether the derivative with respect to time of the throttle position is equal to or greater than zero. In block 710, the controller 34 determines whether the ride height flag is set on, the wheel speed flag is set on, the ABS 26 is inactive, and the derivative with respect to time of the throttle position is equal to or greater than zero.If the ride height flag is set to on, the wheel speed flag is set to on, the ABS 26 is inactive, and the derivative with respect to time of throttle position is equal to or greater than zero, the method 700 proceeds to block 712. In block 712, the controller 34 sets the power hop flag to on.

[0035] With continued reference to Fig.2, after executing block 206, method 200 proceeds to block 208. In block 208, the controller 34 uses a machine learning process to determine that the vehicle is experiencing power hop using sensor data from the at least one IMU when the wheel speed sensors and the ride height sensors are unavailable (i.e., failed). The machine learning algorithm may be developed using recorded power hop data. The machine learning algorithm allows for real-time identification of power hop incidents in the event that both the wheel speed sensors and the ride height sensors are unavailable at the same time.The learning method for the machine learning algorithm may include receiving relevant inputs, labeling the power hop incidents, training the machine learning algorithm, feature selection, cross-validation, outputting results, and comparing the results of the data-driven method (e.g., the machine learning algorithm) with the deterministic algorithm (e.g., method 200). As explained above, the data-driven method (e.g., the machine learning algorithm) is activated when both the wheel speed sensors and the ride height sensors are unavailable at the same time. Further, the data-driven method (e.g., a machine learning algorithm) uses sensor data from one or more IMUs to determine whether a power hop event has occurred. The data-driven method (e.g.,The machine learning algorithm can use primary axle torque, tire temperature, longitudinal acceleration, lateral acceleration, and throttle position to determine if a power hop event has occurred.

[0036] After executing block 208, method 200 proceeds to block 210. In block 210, controller 34 arbitrates between the torque to contain power hop and the powertrain limits. Power hop control, which has the most stringent limits, receives the highest arbitration priority. However, reducing clutch torque may result in reduced vehicle acceleration, particularly during split-friction acceleration events. Therefore, target torque arbitration considers an optimal balance between the power hop magnitude and the allowable wheel slip across the left and right wheels 17. In block 210, controller 34 sets the required torque setting for power hop containment (i.e., the target power hop torque) based on wheel speed.In a given situation, the controller 34 may consider only the power hop target torque and adjust the torque of the vehicle 10 accordingly to mitigate power hop. Additional torque due to yaw error and a wheel steering clutch command may be considered. In other situations where power hop has occurred and wheel steering is active, the controller 34 considers the power hop target torque and the torque vector from other sources (e.g., fixed states and transient commands). If power hop control is disabled, the controller 34 may consider a torque vector from other sources instead of the power hop target torque. In either situation, additional torque due to yaw error and a wheel steering clutch command may be considered.

[0037] While exemplary embodiments are described above, these embodiments are not intended to describe all possible forms encompassed by the claims. The words used in the application text are words of description rather than limitation, and it is understood that various changes may be made without departing from the spirit and scope of the disclosure. As previously described, the features of various embodiments may be combined to form further embodiments of the presently disclosed system and method, which need not be expressly described or illustrated.While various embodiments may have been described as providing advantages or being preferred over other prior art embodiments or implementations with respect to one or more desired characteristics, those skilled in the art will recognize that one or more features or characteristics may be compromised to achieve desired overall system characteristics depending on the specific application and implementation. These features may include, but are not limited to, cost, strength, durability, life cycle cost, marketability, appearance, packaging, size, usability, weight, manufacturability, ease of assembly, etc.Therefore, embodiments that are described as less desirable than other embodiments or prior art implementations with respect to one or more characteristics are not outside the scope of the disclosure and may be desirable for certain applications.

[0038] The drawings are presented in simplified form and are not exactly to scale. For convenience and clarity only, directional terms such as top, bottom, left, right, upward, over, above, below, beneath, back, and front may be used with reference to the drawings. These and similar directional terms should not be construed as limiting the scope of the disclosure in any way.

[0039] Embodiments of the present disclosure are described herein. However, it should be understood that the disclosed embodiments are merely examples, and further embodiments may take various and alternative forms. The figures are not necessarily to scale; some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a representative basis for teaching one skilled in the art to variously employ the presently disclosed system and method.As will be understood by those skilled in the art, various features illustrated and described with reference to any of the figures may be combined with features illustrated in one or more other figures to produce embodiments not explicitly illustrated or described. The combinations of illustrated features provide representative embodiments for typical applications. However, various combinations and modifications of the features consistent with the teachings of this disclosure may be desirable for particular applications or implementations.

[0040] Here, embodiments of the present disclosure may be described in terms of functional and / or logical block components and various processing steps. It should be appreciated that such block components may be implemented by multiple hardware, software, and / or firmware components configured to perform the specified functions. For example, an embodiment of the present disclosure may employ various integrated circuit components, e.g., memory elements, digital signal processing elements, logic elements, lookup tables, or the like, capable of performing a variety of functions under the control of one or more microprocessors or other control devices.In addition, those skilled in the art will understand that embodiments of the present disclosure may be practiced in connection with multiple systems and that the systems described herein are merely exemplary embodiments of the present disclosure.

[0041] For brevity, techniques related to signal processing, data fusion, signaling, control, and other functional aspects of the systems (and the individual operational components of the systems) need not be described in detail here. Furthermore, the interconnections shown in the various figures included herein are intended to represent examples of functional relationships and / or physical couplings between the various elements. It should be noted that alternative or additional functional relationships or physical connections may be present in an embodiment of the present disclosure.

[0042] This description is merely illustrative in nature and is in no way intended to limit the disclosure, its application, or uses. The broad teachings of the disclosure may be implemented in various forms. Therefore, while this disclosure contains specific examples, the true scope of the disclosure should not be so limited, since other modifications will become apparent upon a study of the drawings, the specification, and the following claims.

Claims

[1] Procedure for identifying and mitigating power hop, which includes: Receiving sensor data from a vehicle, the sensor data including wheel speed; Determining a wheel pressure characteristic of the vehicle based on the wheel speed; Determining a ride height of the vehicle; Determining whether the vehicle is experiencing power hop based on the wheel pressure characteristics and the ride height of the vehicle; and Adjusting, in response to determining that the vehicle is experiencing power hop, a torque of the vehicle to contain power hop. [2] The method of claim 1, wherein the wheel pressure characteristics comprise a wheel pressure amplitude and a wheel pressure duration, the wheel pressure amplitude being the second derivative with respect to time of the wheel speed. [3] The method of claim 2, further comprising: Determining whether an absolute value of a change in wheel pressure amplitude within a predetermined period of time is greater than a predetermined amplitude threshold; and Setting a wheel speed flag on in response to determining that the absolute value of the change in wheel pressure amplitude within the predetermined time period is greater than the predetermined amplitude threshold. [4] The method of claim 3, further comprising: Determining whether a change in the ride height of the vehicle within the specified time period is less than a specified ride height threshold; and Setting a ride height flag to on in response to determining that the change in ride height of the vehicle within the specified time period is less than the specified ride height threshold. [5] The method of claim 4, further comprising determining whether an anti-lock braking system (ABS) of the vehicle is inactive. [6] The method of claim 5, further comprising determining whether the derivative with respect to time of a throttle position is equal to or greater than zero. [7] The method of claim 6, further comprising: Determine that the vehicle’s ABS is inactive; Determining that the derivative with respect to time of the throttle position is equal to or greater than zero; Determine that the wheel speed flag is set to On; Determine that the ride height flag is set to On; Setting a power hop flag on in response to: (a) determining that the vehicle's ABS is inactive; (b) determining that the derivative with respect to time of the throttle position is equal to or greater than zero; (c) determining that the wheel speed flag is set on; and (d) determining that the ride height flag is set on. [8] The method of claim 7, wherein the torque of the vehicle is adjusted in response to setting the power hop flag to on to curb the power hop. [9] The method of claim 1, wherein the vehicle includes a plurality of sensors, the plurality of sensors including at least one wheel speed sensor, at least one ride height sensor, and at least one inertial measurement unit (IMU), the wheel speed is determined using the at least one wheel speed sensor of the vehicle, and the ride height is determined using the at least one ride height sensor of the vehicle, and the method further comprises: Determining that the at least one wheel speed sensor is unavailable; Determining that the at least one ride height sensor is unavailable; and In response to determining that the at least one wheel speed sensor is unavailable and determining that the at least one ride height sensor is unavailable, using a machine learning process to determine that the vehicle is experiencing power hop using sensor data from the at least one IMU. [10] The method of claim 9, wherein adjusting the torque of the vehicle to mitigate power hop comprises considering a wheel slip limit.

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