DYNAMIC GAP ADJUSTMENT UNDER DIFFERENT TRAFFIC CONDITIONS

Abstract

A computer-implemented method that, when executed by computing hardware, causes the computing hardware to perform operations that include collecting sensor data from a sensor system of a host vehicle, evaluating sensor data, determining ambient road conditions and a behavior of a lead vehicle, receiving a first following gap selected by the driver, calculating a second following gap based on the ambient road conditions and the behavior of the lead vehicle, adjusting a host vehicle acceleration profile using the second following gap while maintaining at least the first gap between the host vehicle and a lead vehicle,monitoring the behavior of roadway actors in one or more adjacent lanes and adjusting the second gap based on the behavior of the roadway actors in the one or more adjacent lanes.

Description

INTRODUCTION

[0001] The invention relates to a computer-implemented method. The present disclosure generally relates to methods for controlling a vehicle with an advanced driver assistance system.

[0002] The document DE 10 2013 214 308 A1 discloses a computer-implemented method according to the preamble of claim 1. The documents DE 10 2019 211 592 A1, DE 10 2010 020 047 A1, DE 11 2022 000 979 T5, DE 10 2010 032 086 A1 and DE 10 2022 208 272 A1 describe related methods.

[0003] Generally, a host vehicle may be equipped with an advanced driver assistance system (ADAS) that helps maintain control of the host vehicle. Some features or aspects of the ADAS are configured to maintain a set distance between a host vehicle and a lead vehicle. Existing systems are configured so that the host vehicle tracks the lead vehicle or mimics its behavior, which can result in harsh or jerky acceleration profiles that negatively impact the driving experience of one or more passengers in the host vehicle.

[0004] It is an object of the invention to address deficiencies in existing systems and methods. SUMMARY

[0005] The above object is achieved by the features of claim 1. Advantageous further developments emerge from the subclaims.

[0006] A computer-implemented method is provided that, when executed by computing hardware, causes the computing hardware to perform operations.The operations include collecting sensor data from a sensor system of a host vehicle, evaluating the sensor data, determining ambient roadway conditions and behavior of a lead vehicle, receiving a first following gap selected by a driver, calculating a second following gap based on the ambient roadway conditions and behavior of the lead vehicle, adjusting an acceleration profile of the host vehicle using the second following gap while maintaining at least the first following gap between the host vehicle and the lead vehicle, monitoring the behavior of roadway actors in one or more adjacent lanes, and adjusting the second following gap based on the behavior of the roadway actors in the one or more adjacent lanes.

[0007] Determining the ambient road conditions and the behavior of the lead vehicle further includes evaluating a host vehicle speed, a first target following distance time, and a rate of change of the host vehicle with a road condition assessment module. The road condition assessment module is configured to provide an adjusted time gap. Calculating the second following gap further includes evaluating the adjusted time gap, the first following gap, and a minimum allowable gap with a buffer evaluation module. The buffer evaluation module is configured to provide a second target following distance time. Calculating the second following gap further includes evaluating the second target following distance time and a vibration gain with a prediction logic module.

[0008] According to at least one aspect, the second following gap may be continuously calculated according to the ambient road conditions and the behavior of the lead vehicle. The second following gap may be reduced when one or more road actors merge between the lead vehicle and the host vehicle. The second following gap may be increased when road conditions are highly variable. The second following gap may be maintained when road conditions are consistent.

[0009] In another configuration, a system is provided that includes computing hardware and memory hardware in communication with the computing hardware. The memory hardware stores instructions that, when executed in the computing hardware, cause the computing hardware to perform operations.The operations include collecting sensor data from a sensor system of a host vehicle, evaluating the sensor data, determining ambient roadway conditions and behavior of a lead vehicle, receiving a first following gap selected by a driver, calculating a second following gap based on the ambient roadway conditions and behavior of the lead vehicle, adjusting an acceleration profile of the host vehicle using the second following gap while maintaining at least the first following gap between the host vehicle and the lead vehicle, monitoring the behavior of roadway actors in one or more adjacent lanes, and adjusting the second following gap based on the behavior of the roadway actors in the one or more adjacent lanes.

[0010] The system may include one or more of the following optional aspects or steps. For example, the second following gap may be continuously calculated according to the ambient road conditions and the behavior of the lead vehicle. The second following gap may be decreased when one or more road actors merge between the lead vehicle and the host vehicle. The second following gap may be increased when road conditions are highly variable. The second following gap may be maintained when road conditions are consistent.

[0011] In yet another configuration, a computer-implemented method is provided that, when executed by computing hardware, causes the computing hardware to perform operations. The operations include determining a traffic condition status, deactivating a buffer management system if the traffic condition status indicates that consistent traffic surrounds a host vehicle, activating the buffer management system if the traffic condition status indicates that variable traffic surrounds the host vehicle, determining whether lane actor merges are present between the host vehicle and a leader vehicle, and creating either (i) a first buffer if the lane actor merges are present, or (ii) a second buffer if the lane actor merges are not present.

[0012] The method may include one or more of the following optional aspects or steps. For example, the first buffer may further include a preferred follow-up removal time and a cut-in buffer time. The cut-in buffer may be absorbed if one or more thresholds are met and rebuilt if the one or more thresholds are not met.

[0013] In at least one aspect, the second buffer may further include a preferred follow-off time and a no-cut-in buffer time. The no-cut-in buffer time may be absorbed if one or more thresholds are met and rebuilt if the one or more thresholds are not met. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The drawings described here are for illustrative purposes only; they show: Fig. 1 is a schematic diagram of a vehicle environment including a vehicle management system according to principles of the present disclosure; Fig. 2 is an enlarged schematic diagram showing an example of the vehicle management system of Fig. 1 according to the principles of the present disclosure; Fig. 3 a flowchart showing operations of the vehicle management system of Fig. 2 shows; and Fig. 4 a flowchart showing operations of the vehicle management system of Fig. 2 shows.

[0015] In all drawings, corresponding reference symbols designate corresponding parts. DETAILED DESCRIPTION

[0016] Example configurations will now be described more fully with reference to the accompanying drawings. Example configurations are provided so that this disclosure will be thorough and will fully convey the scope of the disclosure to those skilled in the art. Specific details, such as examples of specific components, devices, and methods, are set forth to provide a thorough understanding of configurations of the present disclosure. Those skilled in the art will appreciate that example configurations may be embodied in many different forms.

[0017] The terminology used herein is for the purpose of describing certain example configurations only and is not intended to be limiting. As used herein, the singular articles "a," "an," and "the" are intended to include the plural forms unless the context clearly indicates otherwise. The terms "comprises," "including," "containing," and "having" are inclusive and therefore specify the presence of features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more additional features, steps, operations, elements, components, and / or groups thereof.The method steps, processes, and operations described herein should not be construed as necessarily requiring their performance in the particular order discussed or illustrated, unless specifically identified as an order of performance. Additional or alternative steps may be employed.

[0018] When an element or layer is described as being "on," "engaging with," "connected to," "attached to," or "coupled to" another element or layer, it may be directly on, engaging with, connected to, attached to, or coupled to the other element or layer, or there may be intervening elements or layers. Conversely, when an element is described as being "directly on," "directly engaging with," "directly connected to," "directly attached to," or "directly coupled to" another element or layer, there need not be any intervening elements or layers. Other words used to describe the relationship between elements should be interpreted in a similar way (e.g., "between," "adjacent," etc.).As used herein, the term “and / or” includes any combination of one or more of the associated listed elements.

[0019] The terms "first," "second," "third," etc., may be used herein to describe various elements, components, regions, layers, and / or sections. These elements, components, regions, layers, and / or sections are not intended to be limited by these terms. These terms may be used solely to distinguish one element, component, region, layer, or section from another region, layer, or section. Terms such as "first," "second," and other numerical terms do not imply a sequence or order unless clearly indicated by the context.Thus, a first element, component, region, layer, or section discussed below may be referred to as a second element, component, region, layer, or section without departing from the teachings of the example configurations.

[0020] In this application, including the definitions below, the term "module" may be replaced with the term "circuit." The term "module" may refer to, be part of, or include an application-specific integrated circuit (ASIC); a digital, analog, or mixed analog / digital discrete circuit; a digital, analog, or mixed analog / digital integrated circuit; a combinational logic circuit; a field-programmable gate array (FPGA); a processor (shared, dedicated, or group) that executes code; memory (shared, dedicated, or group) that stores code executed by a processor; other suitable hardware components that provide the described functionality; or a combination of some or all of the above, such as in a system on a chip.

[0021] The term "code" as used above may include software, firmware, and / or microcode and may refer to programs, routines, functions, classes, and / or objects. The term "shared processor" includes a single processor that executes some or all of the code from multiple modules. The term "group processor" includes a processor that, in combination with additional processors, executes some or all of the code from multiple modules. The term "shared memory" includes a single memory that stores some or all of the code from multiple modules. The term "group memory" includes memory that, in combination with additional memory, stores some or all of the code from one or more modules. The term "memory" may be a subset of the term "computer-readable medium."The term "computer-readable medium" encompasses non-transitory electrical and electromagnetic signals propagating through a medium and can therefore be considered tangible and non-transitory storage. Non-limiting examples of non-transitory storage include tangible computer-readable medium, including non-volatile memory, magnetic storage, and optical storage.

[0022] The devices and methods described in this application may be implemented, in part or in whole, by one or more computer programs executed by one or more processors. The computer programs include processor-executable instructions stored on at least one non-transitory, tangible, computer-readable medium. The computer programs may also include and / or access stored data.

[0023] A software application (i.e., a software resource) may refer to computer software that causes a computing device to perform a task. In certain examples, a software application may be referred to as an "application," an "app," or a "program." Example applications include, but are not limited to, system diagnostic applications, system management applications, system maintenance applications, word processing applications, spreadsheet applications, messaging applications, media streaming applications, social networking applications, and gaming applications.

[0024] Non-transitory memory may be physical devices used to store programs (e.g., sequences of instructions) or data (e.g., program state information) on a temporary or permanent basis for use by a computing device. Non-transitory memory may be volatile and / or non-volatile addressable semiconductor memory. Examples of non-volatile memory include, but are not limited to, flash memory and read-only memory (ROM) / programmable read-only memory (PROM) / erasable programmable read-only memory (EPROM) / electronically erasable programmable read-only memory (EEPROM) (which, for example, is typically used for firmware such as boot programs).Examples of volatile memory include, but are not limited to, random access memory (RAM), dynamic random access memory (DRAM), static random access memory (SRAM), phase change memory (PCM), and disk or tape.

[0025] These computer programs (also known as programs, software, software applications, or code) contain machine instructions for a programmable processor and may be implemented in a high-level procedural and / or object-oriented programming language and / or assembly / machine language. As used herein, the terms "machine-readable medium" and "computer-readable medium" refer to a computer program product, a non-transitory computer-readable medium, an apparatus, and / or a device (e.g., magnetic disks, optical disks, memories, programmable logic devices (PLDs)) used to provide machine instructions and / or data to a programmable processor, which contains a machine-readable medium that embodies machine instructions as a machine-readable signal.The term “machine-readable signal” refers to a signal used to provide machine instructions and / or data to a programmable processor.

[0026] Various implementations of the systems and techniques described herein may be realized in digital electronics and / or optical circuitry, integrated circuitry, specially designed ASICs (Application Specific Integrated Circuits), computer hardware, firmware, software, and / or combinations thereof. These various implementations may include implementation in one or more computer programs executable and / or interpretable in a programmable system including at least one programmable processor, which may be special-purpose or general-purpose and coupled to receive data and instructions from and send data and instructions to a memory system, at least one input device, and at least one output device.

[0027] The processes and logic sequences described in this application text may be performed by one or more programmable processors, also referred to as data processing hardware, which execute one or more computer programs to perform functions by operating on input data and generating outputs. The processes and logic sequences may also be performed by special-purpose logic circuitry, such as an FPGA (field-programmable gate array) or an ASIC (application-specific integrated circuit). Processors suitable for executing a computer program include, by way of example, both general-purpose and special-purpose microprocessors and one or more processors of any type of digital computer. Generally, a processor will receive instructions and data from read-only memory and / or random access memory.The essential elements of a computer are a processor for executing instructions and one or more memory devices for storing instructions and data. Generally, a computer also includes, or is operatively coupled to, receiving data from and / or sending data to one or more mass storage devices for storing data, e.g., magnetic disks, magneto-optical disks, or optical disks. However, a computer is not required to include such devices. Computer-readable media suitable for storing computer program instructions and data include all forms of non-volatile memory, media, and storage devices, including, by way of example, semiconductor memory devices, e.g., EPROM, EEPROM, and flash memory devices; magnetic disks, e.g., internal hard disks or removable disks; magneto-optical disks, and CD-ROM and DVD-ROM disks.The processor and memory may be supplemented by or incorporated into special-purpose logic circuitry.

[0028] To provide interaction with a user, one or more aspects of the disclosure may be implemented in a computer having a display device, e.g., a CRT (cathode ray tube), an LCD (liquid crystal display monitor), or a touch screen for displaying information to the user, and optionally a keyboard and a pointing device, e.g., a mouse or trackball, with which the user can provide input to the computer. Other types of devices may also be used to provide interaction with a user; e.g., feedback provided to the user may be any form of sensory feedback, e.g.,visual feedback, auditory feedback, or haptic feedback; and input may be received from the user in any form including auditory, verbal, or tactile input. Additionally, a computer may interact with a user by sending documents to and receiving documents from a device used by the user; e.g., by sending web pages to an internet browser on a user's client device in response to requests received from the internet browser.

[0029] With reference to Fig. 1, an example vehicle operating environment 10 is provided to illustrate the principles of the present disclosure. The vehicle operating environment 10 includes a vehicle service center 20. For illustrative purposes, the vehicle operating environment 10 is shown as including a single vehicle service center 20. However, in further examples, the vehicle operating environment 10 may include multiple vehicle service centers 20 in communication via a network 40 (e.g., the Internet, cellular networks).

[0030] The vehicle operating environment 10 includes a host vehicle 100, a lead vehicle 102, and one or more nearby roadway actors 104. The host vehicle 100 includes a vehicle management system 110 that includes a sensor system 120, a computing system 130, a vehicle control module 140, and an advanced driver assistance system (ADAS) 200. The vehicle management system 110 may be configured to collect information related to ambient traffic conditions and adjust control of the host vehicle 100 accordingly.

[0031] As the host vehicle 100 maneuvers through the environment 10, the sensor system 120 includes various sensor subsystems 122, 122a-122b configured to collect sensor data 123, 123a-123b related to characteristics of the environment 10 and / or a status of the host vehicle 100. The sensor subsystems 122 may include an ADAS sensor subsystem 122a configured to measure or obtain vehicle operating and / or vehicle position data 123a. The ADAS sensor subsystem 122a may include an inertial measurement unit (IMU) 124, one or more wheel speed sensors 125, one or more cameras 126, and other sensors for obtaining vehicle data 123a. The sensor subsystems 122 may also include a vehicle exterior sensor subsystem 122d configured to measure or receive external environmental data 123b, such as surrounding objects (e.g., vehicles, pedestrians). The vehicle exterior sensor subsystem 122b may, for example,an RGB camera and / or an infrared camera and / or a thermal camera and / or a radar and / or an external microphone.

[0032] While the sensor system 120 collects the sensor data 123, a computing system 130 is configured to process, store, and / or communicate the sensor data 123 within the vehicle operating environment 10. To perform computing tasks related to the sensor data 123, the computing system 130 of the host vehicle 100 includes computing hardware 132 and storage hardware 134. The computing hardware 132 is configured to execute instructions stored in the storage hardware 134 to perform computing tasks related to the operation and management of the host vehicle 100. Generally, the computing system 130 refers to one or more locations of computing hardware 132 and / or storage hardware 134.

[0033] In certain examples, the computing system 130 is a local system located within the host vehicle 100. When located within the host vehicle 100, the computing system 130 may be centralized (i.e., located at a single location / area of the host vehicle 100), decentralized (i.e., located at various locations within the host vehicle 100), or a hybrid combination of both (e.g., with a majority of centralized hardware and a minority of decentralized hardware). To illustrate some differences, a decentralized computing system 130 may allow processing to occur at one activity location, while a centralized computing system 130 may allow a central processing hub that communicates with systems located at various locations within the host vehicle 100.

[0034] Additionally or alternatively, computing system 130 includes computing resources located remotely from host vehicle 100. For example, computing system 130 may communicate with a remote vehicle computing system 30 (e.g., a remote computer / server or a cloud-based environment) via network 40. Similar to computing system 130, remote vehicle computing system 30 includes remote computing resources such as remote computing hardware 32 and remote storage hardware 34. Here, sensor data 123 or other processed data (e.g., local data processing by computing system 130) may be stored in remote vehicle computing system 30 and accessible to computing system 130.In certain examples, the computing system 130 is configured to use the remote resources 32, 34 as an extension of the computing resources 132, 134 such that resources of the computing system 130 may be located in resources of the remote vehicle computing system 30.

[0035] With reference to Fig. 1 and Fig. 2, the vehicle management system 110 includes the advanced driver assistance system (ADAS) 200, which may monitor and control one or more electronic aspects of the host vehicle 100 and one or more subsystems of the host vehicle 100. For example, as discussed in more detail below, the ADAS 200 may communicate with the vehicle control module 140 to adjust an acceleration profile of the host vehicle 100 based on ambient traffic conditions, the behavior of the host vehicle 102, or the behavior of one or more nearby roadway actors 104.

[0036] Typically, certain features of an ADAS 200 (e.g., adaptive cruise control) allow drivers to select a first or preferred following gap (e.g., near, medium, far) 202 ( Fig. 1) that can be used by the ADAS 200 to maintain a specific distance or time period 204 between the host vehicle 100 and the lead vehicle 102. In stop-and-go traffic conditions, existing systems may generate harsh or jerky acceleration and deceleration profiles because existing vehicles are typically configured to follow or mimic the behavior of the lead vehicle 102. According to at least one aspect of the present disclosure, the ADAS 200 may include one or more modules to evaluate and / or store sensor data 123 of the sensor system 120 and provide commands to one or more of the systems (e.g., the vehicle control module 140) of the host vehicle 100 to provide a more comfortable driving experience by minimizing motion profile extremes while providing overall conformity to the driver's preferred following gap 202.For example, the ADAS 200 may include a road condition assessment module 220, a buffer evaluation module 240, and a predictive logic module 260.

[0037] In general, the ADAS 200 may be configured to calculate an absorption range or a second following gap 206 that allows for a buffer distance or time 208 between the host vehicle 100 and the lead vehicle 102. The second following gap 206 may be continuously and instantaneously adjusted while the host vehicle 100 is traveling. The second following gap 206 may be desirable to provide a more comfortable driving experience, e.g., in highly unstable traffic conditions and / or when one or more of the nearby roadway actors 104 merge between the host vehicle 100 and the lead vehicle 102. Note that throughout the description, the first following gap 202 and the second following gap 206 may be collectively referred to as the following gap 210.

[0038] With reference to Fig. 2, the road condition assessment module 220 may be configured to evaluate road conditions (i.e., traffic conditions) and determine whether the road conditions are consistent (i.e., steady and smooth driving) or highly variable (i.e., stop-and-go). In other words, the road condition assessment module 220 may be configured to consider the road conditions surrounding the host vehicle 100, the behavior of the lead vehicle 102, measures of average speed and acceleration profiles, the variability of traffic conditions, the period of time, and the frequency of changes in conditions. In at least one aspect, the road condition assessment module 220 may calculate an adjusted time gap 222 based on a host vehicle speed 127, a first target following distance time (i.e., an initial target following distance time) 128, and a host vehicle rate of change 129.In one example, the adjusted time gap 222 may be determined using a lookup table 221 with the host vehicle speed 127, the first desired following distance time 128, and the rate of change 129.

[0039] The buffer evaluation module 240 may be configured to determine a second target following distance time (i.e., an adjusted target following distance time) 242. In certain cases, the second target following distance time will increase the following gap 210 between the host vehicle 100 and the leader vehicle 102, and in other cases, will decrease the following gap 210 between the host vehicle 100 and the leader vehicle 102. In at least one aspect, the second target following distance time 242 may be determined by summing the adjusted time gap 222, a driver-selected gap 244, and a minimum allowable following gap 246.

[0040] Based on the observed behavior of the ambient roadway conditions and the behavior of the host vehicle 102, the predictive logic module 260 may receive the second target following distance time 242 and adjust or change it accordingly. Specifically, a (target) vibration gain 264 is applied to the second target following distance time 242 to determine a third or final target following distance time 262. The third target following distance time 262 is predictive in nature and may help prevent sudden movement (i.e., a jolt) during acceleration and deceleration events.

[0041] With continued reference to Fig. 2, the vehicle control module 140 may be configured to receive the third target following distance time 262 and communicate commands 142 to one or more systems of the host vehicle 100. In certain cases, the third target following distance time 262 may be referred to as a following gap modifier, as the third target following distance time 262 may be used to reduce rough or jerky motion while maintaining a satisfactory following distance between the host vehicle 100 and the lead vehicle 102.

[0042] With reference to Fig. 3, a method 300 is provided for dynamically adjusting the following gap 210 based on the ambient roadway conditions and the behavior of the host vehicle 102. At 302, the method 300 is initiated. Practically speaking, the method 300 is initiated when the driver or the host vehicle 100 activates one or more ADAS features (e.g., adaptive cruise control).

[0043] In 304, sensor data 123 may be collected from one or more sensors of the sensor subsystems 122.

[0044] At 306, the sensor data 123 may be evaluated. For example, the sensor data 123 may be evaluated by the computer system 130, which may be configured with a perception system that may use the sensor data 123, for example, to identify surrounding objects such as vehicles (i.e., the lead vehicle and / or the one or more nearby roadway actors 104) or pedestrians.

[0045] At 308, the ambient road conditions and the behavior of the host vehicle 102 may be determined using the road condition assessment module 220 of the ADAS 200. In general, the road condition assessment module 220 may be configured to determine whether the ambient road conditions and / or the behavior of the host vehicle 102 are consistent or highly variable.

[0046] At 310, the first follow-up gap 202 may be selected by the driver of the host vehicle 100 and received at the ADAS 200. Note that this step may also occur simultaneously or shortly after the method 300 is initiated at 302.

[0047] At 312, the second following gap 206 may be calculated based on the ambient road conditions and the behavior of the host vehicle 102. If the road conditions are highly variable, the second following gap 206 may be increased. If the road conditions are consistent, the second following gap may be maintained.

[0048] At 314, the acceleration profile of the host vehicle 100 may be adjusted with the second following gap 206 while at least maintaining the first following gap 202 between the host vehicle 100 and the lead vehicle 102.

[0049] At 316, the behavior of one or more nearby roadway actors 104 is monitored to determine whether one or more of the nearby roadway actors 104 is merging between the host vehicle 100 and the lead vehicle 102.

[0050] At 318, if one or more of the near lane actors 104 merge between the host vehicle 100 and the lead vehicle 102, the second following gap 206 may be adjusted (e.g., decreased) based on this behavior. In other words, the second following gap may be used to absorb sudden changes in the following gap distance and remove harsh or jerky deceleration profiles of the host vehicle 100.

[0051] In 320 the procedure 300 ends.

[0052] With reference to Fig. 4, a method 400 is provided for dynamically adjusting the follow-up distance time based on vehicle dynamics of a next vehicle in the path (e.g., the host vehicle 102). At 410, the method 400 is initiated. Practically speaking, the method 400 is initiated when the driver or operator powers on the host vehicle 100.

[0053] At 420, a traffic condition status may be evaluated to determine whether conditions surrounding host vehicle 100 are consistent or highly variable (i.e., stop-and-go traffic). The traffic condition status may be determined based on one or more conditions.

[0054] In 422, if the traffic condition status indicates that the traffic conditions are not highly variable, a buffer management system may remain inactive.

[0055] At 424, if the traffic condition status indicates that traffic conditions are highly variable, the buffer management system may be activated. One or more additional conditions may be necessary for the buffer management system to control the host vehicle 100. For example, a speed of the host vehicle may need to be less than a threshold, a number of surrounding roadway actors may need to be greater than a threshold, and / or one or more ADAS features (e.g., adaptive cruise control) may need to be activated.

[0056] At 430, a merge status may be determined, representing whether one or more lane actors 102 are merging between the host vehicle 100 and the lead vehicle 102. For example, if a number of lane actor merges exceeds a threshold, the method 400 may proceed to 440, where a first buffer or follow-through removal time may be generated. Additionally or alternatively, if a time period since the last lane actor merge is less than a threshold, the method 400 may proceed to 440, where the first buffer or follow-through removal time may be generated.

[0057] At 442, the first buffer may be generated, taking into account one or more lane actor merges. According to one aspect, the first buffer time may include a driver's preferred follow-distance time and a merge buffer time. The merge buffer time may be a calibrated time period.

[0058] At 444, one or more conditions may be evaluated to determine whether the first buffer should be absorbed. For example, if the lead vehicle 102 decelerates abruptly, the first buffer may be absorbed (i.e., removed) to allow the host vehicle 100 to use a less aggressive deceleration profile than the lead vehicle 102. In one aspect, the first buffer is to be absorbed if one or more of the following thresholds are met: the speed of the host vehicle 100 relative to the lead vehicle 102 is less than a first buffer threshold, the speed of the lead vehicle 102 relative to the roadway is less than a second buffer threshold, the acceleration of the lead vehicle 102 relative to the host vehicle 100 is less than a third buffer threshold, or the speed of the host vehicle 100 relative to the roadway is less than a fourth buffer threshold.

[0059] In 446, the first buffer is absorbed and the preferred follow-up removal time is maintained.

[0060] At 448, one or more conditions may be evaluated to determine whether the first buffer should be increased. For example, if the lead vehicle 102 abruptly accelerates and moves away from the host vehicle 100, the first buffer may be rebuilt. In one aspect, the first buffer should be rebuilt if one or more of the following thresholds are met: the speed of the host vehicle 100 relative to the lead vehicle 102 is greater than the first buffer threshold, the magnitude speed of the lead vehicle 102 relative to the roadway is greater than the second buffer threshold, the acceleration of the lead vehicle 102 relative to the host vehicle 100 is greater than the third buffer threshold, or the speed of the host vehicle 100 relative to the roadway is greater than the fourth buffer threshold.

[0061] In 442 the first buffer can be rebuilt.

[0062] Returning to 430, if the number of lane actor merges is less than the threshold, the method 400 may proceed to 450, where a second buffer or follow-up removal time may be generated. Additionally or alternatively, if a time period since the last lane actor merge is greater than the threshold, the method 400 may proceed to 450, where the second buffer or follow-up removal time may be generated.

[0063] At 452, the second buffer may be generated under the assumption that no lane actor merges are present. According to one aspect, the second buffer time may include a preferred follow-up distance time of a non-merge buffer time. The non-merge buffer time may be a calibrated time period.

[0064] At 454, one or more conditions may be evaluated to determine whether the second buffer should be absorbed. For example, if the lead vehicle 102 decelerates abruptly, the second buffer may be absorbed (i.e., removed) to allow the host vehicle 100 to use a less aggressive deceleration profile than the lead vehicle 102. In one aspect, the second buffer should be absorbed if one or more of the following thresholds are met: the speed of the host vehicle 100 relative to the lead vehicle 102 is less than a fifth buffer threshold, the magnitude speed of the lead vehicle 102 relative to the roadway is less than a sixth buffer threshold, the acceleration of the lead vehicle 102 relative to the host vehicle 100 is less than a seventh buffer threshold, or the speed of the host vehicle 100 relative to the roadway is less than an eighth buffer threshold.

[0065] In 456, the second buffer is absorbed and the preferred follow-up removal time is maintained.

[0066] At 458, one or more conditions may be evaluated to determine whether the second buffer should be rebuilt (i.e., increased). For example, if the lead vehicle 102 abruptly accelerates and moves away from the host vehicle 100, the second buffer may be rebuilt. In one aspect, the second buffer should be rebuilt if one or more of the following thresholds are met: the speed of the host vehicle 100 relative to the lead vehicle 102 is greater than the fifth buffer threshold, the magnitude speed of the lead vehicle 102 relative to the roadway is greater than the sixth buffer threshold, the acceleration of the lead vehicle 102 relative to the host vehicle 100 is greater than the seventh buffer threshold, or the speed of the host vehicle 100 relative to the roadway is greater than the eighth buffer threshold.

Claims

[1] A computer-implemented method (300) that, when executed by data processing hardware (132), causes the data processing hardware (132) to perform operations comprising: Collecting (304) sensor data (132) from a sensor system (122) of a host vehicle (100); Evaluating (306) the sensor data (123); Determining (308) ambient roadway conditions and a behavior of a lead vehicle (102); Receiving (310) a first subsequent gap (202) selected by a driver; Calculating (312) a second follow-up gap (206) based on the ambient roadway conditions and the behavior of the lead vehicle (102); adjusting (314) an acceleration profile of the host vehicle (100) using the second following gap (206) while maintaining at least the first following gap (202) between the host vehicle (100) and the lead vehicle (102); Monitoring (316) the behavior of roadway actors (104) in one or more adjacent lanes; and adjusting (318) the second following gap (206) based on the behavior of the roadway actors (104) in the one or more adjacent lanes, wherein determining (308) the ambient road conditions and the behavior of the lead vehicle (102) further comprises evaluating a host vehicle speed (127), a first target following distance time (128), and a rate of change (129) of the host vehicle (100) with a road condition assessment module (220), wherein the road condition assessment module (220) is configured to provide an adjusted time gap (222), wherein calculating (312) the second sequential gap (206) further comprises evaluating the adjusted time gap (222), the first sequential gap (202) and a minimum allowable gap with a buffer evaluation module (240), wherein the buffer evaluation module (240) is configured to provide a second target follow-up distance time (242), characterized by , that calculating (312) the second following gap (206) further comprises evaluating the second target following distance time (242) and a vibration gain (264) with a prediction logic module (260), wherein the predictive logic module (260) applies the vibration gain (264) to the second target following distance time (242) to determine a third target following distance time (262) based on the observed behavior of the ambient roadway conditions and the behavior of the host vehicle (102). [2] The method (300) of claim 1, wherein the second following gap (206) is continuously calculated according to the ambient roadway conditions and the behavior of the lead vehicle (102). [3] The method (300) of claim 2, wherein the second following gap (206) is reduced when one or more lane actors (104) merge between the lead vehicle (102) and the host vehicle (100). [4] The method (300) of claim 3, wherein the second following gap (206) is increased when the road conditions are highly variable. [5] The method (300) of claim 4, wherein the second following gap (206) is maintained when the road conditions are consistent.

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