A method and system for determining a longitudinal target acceleration of a vehicle

Abstract

The application provides a method and system for determining a longitudinal target acceleration of a vehicle, and relates to the technical field of vehicle control. The method comprises the following steps: in the case that a cruise mode is turned on, determining a current time target vehicle speed of each of a plurality of cruise scenarios according to a target distance, a current vehicle speed, and preconfigured parameter values of the plurality of cruise scenarios; determining a current time target vehicle speed in the cruise mode according to the current time target vehicle speed of each of the plurality of cruise scenarios; determining a current speed deviation according to the current vehicle speed and the current time target vehicle speed in the cruise mode, and determining a current comfort acceleration according to the current speed deviation; determining a current emergency braking acceleration according to the current vehicle speed and the target distance; determining a current time target acceleration in the cruise mode from the current comfort acceleration and the current emergency braking acceleration, and the current time target acceleration in the cruise mode is used for longitudinal acceleration control of the vehicle. The application aims to improve the comfort of automatic parking of the vehicle.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, specifically to a method and system for determining the longitudinal target acceleration of a vehicle. Background Technology

[0002] With the increasing popularity of intelligent driving technology, Automatic Parking Assist (APA) and Automated Valet Parking (AVP) have become key functions for enhancing user experience. During vehicle longitudinal motion control, the accuracy and rationality of the target acceleration calculation directly determine the efficiency and safety of parking. In existing technologies, determining the longitudinal target acceleration typically relies on feedback adjustment based on the deviation between the current vehicle speed and the target speed. Some solutions combine simple distance thresholds to assist in speed limiting or braking decisions, and the control parameters are mostly fixed configurations.

[0003] However, such conventional methods have certain limitations in practical applications. On the one hand, due to their relatively simple control strategies, they are difficult to fully cope with complex and ever-changing dynamic traffic scenarios; on the other hand, when the vehicle's operating conditions change or when it faces sudden risks, the continuity and smoothness of acceleration control may be affected, thereby impacting the driving experience. Summary of the Invention

[0004] In view of this, this application provides a method and system for determining the longitudinal target acceleration of a vehicle. It aims to solve or partially solve the problems existing in the prior art.

[0005] The first aspect of this application provides a method for determining the longitudinal target acceleration of a vehicle, the method comprising: When cruise mode is enabled, the target speed for each of the various cruise scenarios is determined based on the target distance, current vehicle speed, and pre-configured parameter values ​​for each cruise scenario. The target distance is the distance from the vehicle to the target location or obstacle. The various cruise scenarios include at least two of the following: following vehicle scenario, yielding to other vehicles scenario, and yielding to pedestrian scenario. Determine the target vehicle speed at the current moment under cruise mode based on the target vehicle speed at the current moment for each of the various cruise scenarios. Based on the current vehicle speed and the target vehicle speed at the current moment in cruise mode, determine the current vehicle speed deviation, and based on the current vehicle speed deviation, determine the current comfort acceleration; Determine the current emergency braking acceleration based on the current vehicle speed and target distance; The target acceleration at the current moment in cruise mode is determined from the current comfort acceleration and the current emergency braking acceleration. The target acceleration at the current moment in cruise mode is used to control the longitudinal acceleration of the vehicle.

[0006] Optionally, when cruise mode is enabled, the target speed for each of the various cruise scenarios is determined based on the target distance, current vehicle speed, and pre-configured parameter values ​​for each scenario, including: When cruise mode is enabled, the remaining available distance for each cruise scenario is determined based on the target distance, current vehicle speed, and the pre-configured safe distance for each cruise scenario. Based on the current vehicle speed, the pre-configured acceleration for each of the various cruise scenarios, and the current remaining available distance, determine the target vehicle speed for each of the various cruise scenarios at the current moment.

[0007] Optionally, the target acceleration for the current moment in cruise mode can be determined from the current comfort acceleration and the current emergency braking acceleration, including: Determine the current safe distance based on the current vehicle speed; If the target distance is less than the current safe distance, the current state of emergency braking is set to active; if the target distance is not less than the current safe distance, the current state of emergency braking is set to deactivated. If the emergency braking is currently active and the current emergency braking acceleration is less than the current comfort acceleration, the current emergency braking acceleration will be determined as the target acceleration for the current moment in cruise mode. If the current state of emergency braking is deactivated, or if the current emergency braking acceleration is not less than the current comfort acceleration, the current comfort acceleration is determined as the target acceleration at the current moment in cruise mode.

[0008] Optionally, the target acceleration for the current moment in cruise mode can be determined from the current comfort acceleration and the current emergency braking acceleration, including: If the current vehicle speed is greater than the vehicle speed threshold, obtain the target acceleration at the previous moment. If the emergency braking is currently active and the current emergency braking acceleration is less than the current comfort acceleration, the target acceleration for the current moment in cruise mode is determined based on the emergency braking filter coefficient, the current emergency braking acceleration, and the previous target acceleration. If the emergency braking is currently deactivated, or if the current emergency braking acceleration is not less than the current comfort acceleration, the target acceleration for the current moment in cruise mode is determined based on the comfort filter coefficient, the current comfort acceleration, and the target acceleration of the previous moment, with the comfort filter coefficient being less than the emergency braking filter coefficient.

[0009] Optionally, the current emergency braking acceleration can be determined based on the current vehicle speed and target distance, including: Determine the current safe distance based on the current vehicle speed; Determine the current emergency braking coefficient based on the difference between the current safe distance and the target distance; Determine the current emergency braking acceleration based on the current vehicle speed, target distance, and current emergency braking coefficient.

[0010] Optionally, determine the current comfort acceleration based on the current vehicle speed deviation, including: Determine the initial proportional coefficient based on the vehicle speed type of the current vehicle speed; The initial proportional coefficient is adjusted based on at least one of the following: current speed deviation, road length, current remaining available distance of the target cruise scenario, whether the vehicle is in the starting phase, and acceleration deviation. The adjusted proportional coefficient is obtained. The target cruise scenario is the cruise scenario corresponding to the target vehicle speed at the current moment in cruise mode. The acceleration deviation is the deviation between the comfort acceleration of two adjacent historical moments. The current comfort acceleration should be determined based at least on the adjusted proportional coefficient and the current vehicle speed deviation.

[0011] Optionally, the current comfort acceleration may be determined based at least on the adjusted proportional coefficient and the current vehicle speed deviation, including: Determine the initial integral coefficient based on the vehicle speed type of the current vehicle speed; Based on the current vehicle speed deviation, query the correspondence between the vehicle speed deviation and the integral compensation coefficient, and determine the current integral compensation coefficient; The cumulative amount of points in the current integration period is determined based on the current integration compensation coefficient, integration period, current vehicle speed deviation, and cumulative amount of points in the previous integration period. The current comfort acceleration is determined based on the accumulated points of the current integration cycle, the initial integration coefficient, the adjusted proportional coefficient, and the current vehicle speed deviation.

[0012] Optional, also includes: Determine the initial maximum acceleration based on the road length; Determine the vehicle speed type coefficient based on the current vehicle speed type; Determine the vehicle speed deviation coefficient based on the current vehicle speed deviation; Determine the road slope coefficient based on the road gradient; The initial maximum acceleration is adjusted based on at least one of the road gradient coefficient, vehicle speed deviation coefficient, and vehicle speed type coefficient to obtain the adjusted maximum acceleration. Determine the target acceleration for the current moment in cruise mode from the current comfort acceleration and the current emergency braking acceleration, including: Using the adjusted maximum acceleration as the upper limit, the target acceleration for the current moment in cruise mode is determined from the current comfort acceleration and the current emergency braking acceleration.

[0013] Optional, also includes: When the target vehicle speed is zero and the vehicle is stationary at the current moment in cruise mode, the target acceleration at the current moment in cruise mode is limited to a first acceleration range, which is used to keep the vehicle stationary. When the distance between the vehicle and the target location or obstacle is less than a preset distance, the target acceleration at the current moment in cruise mode is limited to not exceed the target acceleration at the previous moment.

[0014] A second aspect of this application provides a system for determining the longitudinal target acceleration of a vehicle, the system comprising: The first target speed determination module is used to determine the target speed at the current moment for each of the various cruise scenarios when cruise mode is enabled, based on the target distance, current speed, and pre-configured parameter values ​​for each of the various cruise scenarios. The target distance is the distance from the vehicle to the target location or obstacle. The various cruise scenarios include at least two of the following: following vehicle scenario, yielding to other vehicles scenario, and yielding to pedestrian scenario. The second target vehicle speed determination module is used to determine the target vehicle speed at the current moment in cruise mode based on the target vehicle speed at the current moment in various cruise scenarios. The comfort acceleration determination module is used to determine the current vehicle speed deviation based on the current vehicle speed and the target vehicle speed at the current moment in cruise mode, and to determine the current comfort acceleration based on the current vehicle speed deviation. The emergency braking acceleration determination module is used to determine the current emergency braking acceleration based on the current vehicle speed and the target distance. The target acceleration determination module is used to determine the target acceleration at the current moment in cruise mode from the current comfort acceleration and the current emergency braking acceleration. The target acceleration at the current moment in cruise mode is used to control the longitudinal acceleration of the vehicle.

[0015] The method for determining the longitudinal target acceleration of a vehicle provided in this application has the following advantages: The method for determining the longitudinal target acceleration of a vehicle provided in this application firstly determines the current target vehicle speed for each of the various cruise scenarios when cruise mode is activated, based on the target distance, current vehicle speed, and pre-configured parameter values ​​for each of the various cruise scenarios. The target distance is the distance from the vehicle to the target location or obstacle. The various cruise scenarios include at least two of the following: following vehicle scenario, yielding to other vehicles scenario, and yielding to pedestrian scenario. Based on the current target vehicle speed for each of the various cruise scenarios, the current target vehicle speed in cruise mode is determined. Based on the current vehicle speed and the current target vehicle speed in cruise mode, the current speed deviation is determined, and based on the current speed deviation, the current comfort acceleration is determined. Based on the current vehicle speed and the target distance, the current emergency braking acceleration is determined. From the current comfort acceleration and the current emergency braking acceleration, the current target acceleration in cruise mode is determined, and the current target acceleration in cruise mode is used for longitudinal acceleration control of the vehicle.

[0016] The method provided in this application calculates the target vehicle speed for various cruise scenarios, such as following other vehicles, yielding to other vehicles, and yielding to pedestrians, and selects the minimum value as the target vehicle speed in cruise mode. This achieves differentiated speed control for different risk scenarios, thereby effectively ensuring safety during parking cruise. Simultaneously, this application processes comfort acceleration calculated based on vehicle speed deviation and emergency braking acceleration based on distance judgment separately, and determines the final target acceleration through fusion logic. This allows the vehicle to maintain a smooth and comfortable acceleration and deceleration experience during normal driving, while prioritizing emergency braking to ensure safety when there is a collision risk. This hierarchical adaptive control mechanism effectively solves the problems of insufficient safety or poor comfort in complex parking scenarios, thereby improving the overall vehicle operating efficiency and user experience in automatic parking scenarios. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the description of the embodiments of this application will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 A flowchart illustrating a method for determining the longitudinal target acceleration of a vehicle, as shown in one embodiment of this application; Figure 2 This is a flowchart illustrating the determination of target velocity in a method for determining the longitudinal target acceleration of a vehicle, as shown in one embodiment of this application. Figure 3 Another flowchart illustrating a method for determining the longitudinal target acceleration of a vehicle, as shown in one embodiment of this application; Figure 4 This is a schematic diagram illustrating a system for determining the longitudinal target acceleration of a vehicle, as shown in one embodiment of this application. Detailed Implementation

[0019] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0020] This embodiment provides a method for determining the longitudinal target acceleration of a vehicle, applicable to longitudinal motion control of vehicles in scenarios such as Automated Valet Parking (AVP) and Automatic Parking Assist (APA). Automated Valet Parking is a long-distance automated parking scenario, such as when a driver drives to the entrance of an underground parking garage in a shopping mall or office building, and the user instructs the vehicle to automatically start from that location, find an empty parking space in the garage, avoid pedestrians and vehicles, and finally park and lock the car. Automatic Parking Assist is a short-distance automated parking scenario, such as when a driver finds a parking space, but the space is too narrow and the driver does not want to park manually; in this case, the vehicle system completes the reverse parking or parallel parking maneuver on behalf of the driver (or assists the driver).

[0021] refer to Figure 1 , Figure 1 This is a flowchart illustrating a method for determining the longitudinal target acceleration of a vehicle, as shown in one embodiment of this application. Figure 1 As shown, the method includes: Step S101: With cruise mode enabled, determine the target speed for each of the various cruise scenarios at the current moment based on the target distance, current vehicle speed, and pre-configured parameter values ​​for each cruise scenario; the target distance is the distance from the vehicle to the target location or obstacle; the various cruise scenarios include at least two of the following: following vehicle scenario, yielding to other vehicles scenario, and yielding to pedestrian scenario.

[0022] In this embodiment, during the parking process in cruise control mode, the vehicle may encounter different dynamic obstacle situations (such as dynamic obstacle situations in a following vehicle scenario, dynamic obstacle situations in a yielding vehicle scenario, and dynamic obstacle situations in a pedestrian yielding scenario). Therefore, during automatic parking in cruise control mode, this application simultaneously calculates the target vehicle speed for multiple cruise scenarios. The target vehicle speed at a given moment is the vehicle's expected safe speed at that moment. These multiple cruise scenarios include at least two of the following: a following vehicle scenario, a yielding vehicle scenario, and a pedestrian yielding scenario.

[0023] Specifically, this application pre-configures the values ​​of corresponding pre-configured parameters for each cruise scenario. When cruise mode is enabled, the target speed of the vehicle at the current moment in the i-th cruise scenario is calculated based on the target distance of the vehicle, the current vehicle speed, and the values ​​of the pre-configured parameters for the i-th cruise scenario, where i is a positive integer from 1 to N, and N is the total number of cruise scenarios. The target speed at the current moment for each cruise scenario can be calculated using the same implementation method.

[0024] The target distance is the distance from the vehicle to the target location or obstacle. During cruise control, the target distance is the distance from the vehicle to the obstacle ahead; when the vehicle is located in a parking space and begins to park, the target distance is the distance from the vehicle to the final parking position (i.e., the target location).

[0025] Step S102: Determine the target vehicle speed at the current moment in cruise mode based on the target vehicle speed at the current moment for each of the various cruise scenarios.

[0026] In this embodiment, such as Figure 2 As shown, to ensure safety in complex parking environments, based on the target vehicle speed calculated in step S101 for each cruise scenario, the target vehicle speed with the smallest value is selected from all the target vehicle speeds for all cruise scenarios as the final target vehicle speed for the cruise mode. This is because during automatic parking, the speed limit requirements for any single scenario must be strictly adhered to, and selecting the minimum value ensures that the vehicle remains within a safe speed range in all potentially risky scenarios. When cruise control is not activated, the speed calculation method for normal parking scenarios is used to calculate the target speed.

[0027] If Distance To Collision (DTC) is activated, this step further includes a secondary comparison between the calculated current collision avoidance target speed and the smallest selected current target speed. The smaller of the two target speeds is then chosen as the final current target speed in cruise mode to further ensure collision avoidance safety. The calculation of the current collision avoidance target speed will be explained in subsequent implementation methods.

[0028] Furthermore, to ensure the smoothness of the target vehicle speed change, this application applies a first-order low-pass filter to the target vehicle speed at the current moment in the final determined cruise mode. This avoids potential longitudinal vibrations caused by sudden changes in the target vehicle speed. Finally, the target vehicle speed obtained after the first-order low-pass filtering is determined as the target vehicle speed at the current moment in cruise mode. When the vehicle is stationary or in the process of dynamic gear shifting, no filtering is performed.

[0029] Step S103: Determine the current speed deviation based on the current vehicle speed and the target vehicle speed at the current moment in cruise mode, and determine the current comfort acceleration based on the current speed deviation.

[0030] In this embodiment, the difference between the target vehicle speed at the current moment in cruise mode, as determined in step S102, and the vehicle's current actual speed (i.e., current speed), is calculated to obtain the current speed deviation. The calculation expression is as follows: ,in, This represents the current vehicle speed deviation. The target vehicle speed at the current moment in cruise mode; This represents the vehicle's current speed. This deviation reflects the difference between the expected safe speed and the vehicle's current actual speed. Based on this current speed deviation, the current comfort acceleration is calculated. The calculation of comfort acceleration aims to ensure smooth vehicle operation and avoid sudden acceleration or deceleration.

[0031] In this embodiment, for the current vehicle speed deviation, this application sets an upper limit and a lower limit to constrain the value of the current vehicle speed deviation. Specifically, when the calculated current vehicle speed deviation is greater than the upper limit, the current vehicle speed deviation is updated to the upper limit; when the calculated current vehicle speed deviation is less than the lower limit, the current vehicle speed deviation is updated to the lower limit. This means that when the vehicle speed deviation is large (e.g., due to emergency braking), this method will not amplify the control output indefinitely, but will compensate for the magnitude of the vehicle speed deviation and set an upper limit. This prevents instantaneous overload of acceleration commands due to excessive vehicle speed deviation. In cruise mode (non-stop phase), the vehicle does not need to react drastically to small speed fluctuations. Therefore, a lower limit is introduced, allowing a certain degree of vehicle speed deviation to exist, without necessarily eliminating it completely. This reduces the system's sensitivity, avoids frequent acceleration and deceleration during long-distance cruise, and improves comfort.

[0032] Step S104: Determine the current emergency braking acceleration based on the current vehicle speed and target distance.

[0033] In this embodiment, comfort acceleration is used to ensure smooth vehicle movement and avoid sudden acceleration or deceleration. However, in actual driving, unexpected dangerous situations or nearby obstacles may be encountered. To cope with these situations, this application calculates both the current comfort acceleration and the current emergency braking acceleration. Specifically, based on kinematic relationships and considering the current vehicle speed and target distance, an acceleration value (usually a negative value) is calculated that can safely stop or decelerate the vehicle to a safe speed within the current distance, and this value is used as the current emergency braking acceleration.

[0034] Step S105: Determine the target acceleration at the current moment in cruise mode from the current comfort acceleration and the current emergency braking acceleration. The target acceleration at the current moment in cruise mode is used to control the longitudinal acceleration of the vehicle.

[0035] In this embodiment, a selection or fusion is made between the current comfort acceleration calculated in step S103 and the current emergency braking acceleration calculated in step S104, outputting the final target acceleration for the current moment in cruise mode. This output is then sent to the vehicle's brake actuators (such as the IBCU Integrated Brake Control Unit) and power actuators (VCUVehicle Control Unit) for longitudinal acceleration control. To balance driving smoothness and safety, the preferred acceleration command is determined based on the current safety status. Typically, if no emergency avoidance logic is triggered, comfort acceleration is prioritized to ensure passenger experience; once a close proximity or collision risk is detected, emergency braking acceleration is switched to ensure parking safety. Before output, the target acceleration for the current moment in cruise mode undergoes smoothing filtering to avoid vehicle jerking caused by step signals from the actuators. The final determined target acceleration directly controls the vehicle's longitudinal torque, achieving precise stopping or speed maintenance along the parking path. Figure 3 As shown, the method provided in this application mainly includes three parts: acquiring input data for calculating vehicle speed deviation and target acceleration; calculating target acceleration based on the acquired input data; and outputting target acceleration based on the determined target acceleration at the current moment, which is then sent to the vehicle's brake actuator (such as IBCU Integrated BrakeControl Unit) and power actuator (VCU Vehicle Control Unit) for longitudinal acceleration control of the vehicle.

[0036] The method provided in this application calculates the target vehicle speed for various cruise scenarios, such as following other vehicles, yielding to other vehicles, and yielding to pedestrians, and selects the minimum value as the target vehicle speed in cruise mode. This achieves differentiated speed control for different risk scenarios, thereby effectively ensuring safety during parking cruise. Simultaneously, this application processes comfort acceleration calculated based on vehicle speed deviation and emergency braking acceleration based on distance judgment separately, and determines the final target acceleration through fusion logic. This allows the vehicle to maintain a smooth and comfortable acceleration and deceleration experience during normal driving, while prioritizing emergency braking to ensure safety when there is a collision risk. This hierarchical adaptive control mechanism effectively solves the problems of insufficient safety or poor comfort in complex parking scenarios, thereby improving the overall vehicle operating efficiency and user experience in automatic parking scenarios.

[0037] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for determining the longitudinal target acceleration of a vehicle, wherein step S101 may include the following steps: Step S101_1: With cruise mode enabled, determine the current remaining available distance for each of the various cruise scenarios based on the target distance, current vehicle speed, and the pre-configured safe distances for each cruise scenario.

[0038] In this embodiment, the application pre-configures the values ​​of corresponding pre-configured parameters for each specific cruise scenario (such as following another vehicle, yielding to other vehicles, and yielding to pedestrians). These pre-configured parameters include a pre-configured safe distance and a pre-configured acceleration.

[0039] The pre-configured safe distance refers to the minimum distance that must be maintained to allow a vehicle to come to a complete stop or remain relatively stationary. This pre-configured safe distance is a static, fixed value, and corresponding pre-configured safe distances are set for different cruising scenarios. Among them, the static safe distance is the largest in the pedestrian yielding scenario (because pedestrians are vulnerable road users and their movement trajectory is unpredictable, requiring the greatest safety redundancy); the static safe distance is medium in the vehicle yielding scenario (because vehicles crossing laterally may suddenly accelerate or change lanes, posing a higher risk, but less than the risk to pedestrians); and the static safe distance is the smallest in the following scenario (because the movement trajectory of the vehicle in front is relatively controllable, and the risk is lower).

[0040] Pre-configured acceleration represents the maximum comfortable deceleration or acceleration capability allowed for a vehicle to safely adjust its speed (typically deceleration or maintenance) within the remaining usable distance. Different cruising scenarios correspond to different comfort levels and risk tolerances; therefore, the pre-configured acceleration value matching the cruising scenario can be obtained by looking up a table or configuring the settings. From a safety perspective, in this application, the pre-configured acceleration value is the lowest for the pedestrian yielding scenario, the medium for the vehicle yielding scenario, and the highest for the following scenario.

[0041] In this embodiment, when cruise mode is enabled, the current remaining available distance for each cruise scenario is first calculated based on the target distance, current vehicle speed, and the pre-configured safe distance for each cruise scenario.

[0042] The expression for calculating the current remaining available distance is:

[0043] in, This represents the current remaining available distance. Distance to target; Pre-configured safe distance for corresponding cruise scenarios; Current vehicle speed; This is the preset time interval.

[0044] The product of the current vehicle speed and the preset time interval is a dynamic safety distance value. This preset time interval can be dynamically adjusted based on the vehicle's actual acceleration, the relative speed of obstacles, and the current vehicle speed. The smaller the actual acceleration, the smaller the preset time interval; the greater the relative speed of obstacles, the larger the preset time interval; and the greater the current vehicle speed, the larger the preset time interval. This expression can be used to calculate the current remaining available distance for each cruise scenario.

[0045] After obtaining the current remaining available distance for each cruise scenario, the target vehicle speed for each cruise scenario at the current moment is calculated based on the current vehicle speed, the pre-configured acceleration for each cruise scenario, and the current remaining available distance.

[0046] The expression for calculating the target vehicle speed at the current moment is:

[0047] in, The target speed at the current moment; Current vehicle speed; This represents the current remaining available distance. This is the pre-configured acceleration for the corresponding cruise scenario. The target vehicle speed at the current moment can be calculated using this expression for each cruise scenario.

[0048] In this embodiment, the calculation of the target vehicle speed for collision avoidance at the current moment is the same as the calculation expression for the target vehicle speed at the current moment, except that the pre-configured safe distance setting is more stringent when DTC is activated (i.e., the reserved safety buffer is smaller or completely based on the physical braking limit) to ensure that a collision can be avoided within the shortest distance; and the pre-configured acceleration is also set more stringently, and the limit braking capacity or emergency deceleration should be taken here, because the purpose is to prevent collisions, so it is assumed that the vehicle has the maximum available safe deceleration capacity when calculating.

[0049] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for determining the longitudinal target acceleration of a vehicle, wherein step S105 may include the following steps: Step S105_1a: Determine the current safe distance based on the current vehicle speed; if the target distance is less than the current safe distance, determine the current state of emergency braking as active; if the target distance is not less than the current safe distance, determine the current state of emergency braking as deactivated.

[0050] In this embodiment, one possible implementation for determining the target acceleration at the current moment in cruise mode is as follows: First, based on the vehicle's current speed, determine the current safe distance. One possible calculation expression is: ,in, This is the current safe distance; This refers to the distance conversion factor; Current vehicle speed; This refers to the emergency braking time gap. This current safe distance is used to determine whether to activate emergency braking. Its value increases with the current vehicle speed, reflecting the need for a longer safe distance to ensure braking safety at high speeds. The emergency braking time gap is a preset reference time buffer amount to allow for the vehicle's perception, decision-making, and execution mechanisms to react before the emergency braking logic is triggered. Its value is a fixed calibration value. The distance conversion factor is a scaling factor used to convert vehicle speed information into a nominal safe distance value. This parameter can be set to 1.0 and adjusted according to road conditions or driving risk level (e.g., 1.2 under high driving risk levels).

[0051] If the target distance is less than the current safe distance, the current state of emergency braking is set to active. If the target distance is not less than the current safe distance, the current state of emergency braking is set to deactivated.

[0052] Step S105_2a: If the current state of emergency braking is active and the current emergency braking acceleration is less than the current comfort acceleration, the current emergency braking acceleration is determined as the target acceleration at the current moment in cruise mode; if the current state of emergency braking is deactivated, or if the current emergency braking acceleration is not less than the current comfort acceleration, the current comfort acceleration is determined as the target acceleration at the current moment in cruise mode.

[0053] In this embodiment, after obtaining the current state of emergency braking through step S105_1a, if the current state of emergency braking is active and the value of the current emergency braking acceleration (usually a negative deceleration) is less than the value of the current comfort acceleration (i.e., more inclined to decelerate or decelerate more forcefully), the current emergency braking acceleration is determined as the target acceleration at the current moment in cruise mode to ensure that the risk is reduced in the shortest possible time.

[0054] If the emergency braking is currently deactivated (in which case there is sufficient safe distance), or if the current emergency braking acceleration is not less than the current comfort acceleration (meaning that comfort control is sufficient to handle the current situation), then the current comfort acceleration is determined as the target acceleration for the current moment in cruise mode. This logic ensures that a comfortable driving experience is maintained as much as possible while meeting safety requirements.

[0055] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for determining the longitudinal target acceleration of a vehicle, wherein step S105 may include the following steps: Step S105_1b: If the current vehicle speed is greater than the vehicle speed threshold, obtain the target acceleration at the previous moment.

[0056] In this embodiment, to ensure control continuity during high-speed cruising or rapid approach to obstacles, parking control is based on historical data. When the current vehicle speed exceeds a preset speed threshold (e.g., 3 m / s), indicating that the vehicle is traveling at high speed, the target acceleration value from the previous moment is obtained as a reference. This step prepares for subsequent smoothing filtering, preventing abrupt changes in acceleration commands during sudden speed changes.

[0057] Step S105_2b: When the current state of emergency braking is active and the current emergency braking acceleration is less than the current comfort acceleration, determine the target acceleration at the current moment in cruise mode based on the emergency braking filter coefficient, the current emergency braking acceleration and the previous target acceleration. In this embodiment, the method for determining the current state of emergency braking (including the active state and the deactivated state) is the same as the method for step S105_1a in the previous embodiment.

[0058] When the current vehicle speed is greater than the speed threshold, emergency braking is currently active, and the current emergency braking acceleration is less than the current comfort acceleration, a weighted fusion of the current emergency braking acceleration and the previous target acceleration is performed using a large emergency braking filter coefficient (typically close to 1) to obtain the current target acceleration in cruise mode. A large emergency braking filter coefficient allows emergency braking control to respond quickly to risks encountered by the vehicle, thereby improving vehicle safety during parking. The specific calculation expression is as follows:

[0059] in, Accelerate the target at the current moment; This is the emergency braking filter coefficient, and its value is larger than that of the comfort filter coefficient. The target acceleration is the acceleration from the previous moment; if the current vehicle speed is greater than the vehicle speed threshold, the current state of emergency braking is active, and the current emergency braking acceleration is less than the current comfort acceleration, This refers to the current emergency braking acceleration.

[0060] If the current vehicle speed is greater than the vehicle speed threshold, the current emergency braking state is active, and the current emergency braking acceleration value is less than the current comfort acceleration value, but the vehicle is in the process of dynamic gear shifting, then the current emergency braking acceleration is directly used as the target acceleration at the current moment, without fusion processing.

[0061] Step S105_3b: If the current state of emergency braking is deactivated, or if the current emergency braking acceleration is not less than the current comfort acceleration, determine the current target acceleration in cruise mode based on the comfort filter coefficient, the current comfort acceleration, and the target acceleration of the previous moment, wherein the comfort filter coefficient is less than the emergency braking filter coefficient.

[0062] In this embodiment, when the current vehicle speed is greater than a speed threshold and the current state of emergency braking is deactivated (or, when the current vehicle speed is greater than a speed threshold and the current emergency braking acceleration is not less than the current comfort acceleration), a small comfort filter coefficient (e.g., 0.1-0.3) is used to weight and fuse the current comfort acceleration and the target acceleration from the previous moment to obtain the target acceleration at the current moment in cruise mode. Since the goal of comfort acceleration is smoothness rather than instantaneous response, a smaller filter coefficient can suppress abrupt changes in acceleration commands, making the vehicle's acceleration and deceleration process smoother. The specific calculation expression is as follows:

[0063] in, Accelerate the target at the current moment; The comfort filter coefficient; The target acceleration at the previous moment; when the current vehicle speed is greater than the vehicle speed threshold and the current state of emergency braking is deactivated (or, when the current vehicle speed is greater than the vehicle speed threshold and the current emergency braking acceleration is not less than the current comfort acceleration). Accelerate for current comfort.

[0064] If the current vehicle speed is greater than the vehicle speed threshold and the current state of emergency braking is deactivated (or, if the current vehicle speed is greater than the vehicle speed threshold and the current emergency braking acceleration is not less than the current comfort acceleration), but the vehicle is in the process of dynamic gear shifting, then the current comfort acceleration is directly used as the target acceleration at the current moment, without fusion processing.

[0065] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for determining the longitudinal target acceleration of a vehicle, wherein step S104 of the method may include the following steps: Step S104_1: Determine the current safe distance based on the current vehicle speed; determine the current emergency braking coefficient based on the distance difference between the current safe distance and the target distance.

[0066] In this embodiment, one possible implementation for determining the current emergency braking acceleration is as follows: First, based on the vehicle's current speed, determine the current safe distance. One possible calculation expression is: ,in, This is the current safe distance; This refers to the distance conversion factor; Current vehicle speed; This refers to the emergency braking time interval.

[0067] Then, the distance difference between the current safe distance and the target distance is calculated. This difference, calculated as the current safe distance minus the target distance, represents the depth to which the vehicle has intruded into or exceeded the safety boundary. A value of 0 indicates that the vehicle has just reached the safety boundary, while a larger value indicates that the vehicle is closer to the obstacle, the higher the risk, and the stronger the braking capability required. Based on this distance difference, the current emergency braking coefficient is dynamically adjusted. The larger the distance difference, the larger the emergency braking coefficient, thereby amplifying the braking effect.

[0068] Step S104_2: Determine the current emergency braking acceleration based on the current vehicle speed, target distance, and current emergency braking coefficient.

[0069] In this embodiment, the current emergency braking acceleration is finally calculated using the current vehicle speed, target distance, and the obtained current emergency braking coefficient. The specific calculation expression is as follows:

[0070] in, This represents the current emergency braking acceleration; k is the velocity-acceleration conversion coefficient, which is a fixed calibration value. This represents the current emergency braking coefficient. Distance to target; This represents the current vehicle speed.

[0071] Because the emergency braking coefficient dynamically increases with the degree of danger, the final emergency braking acceleration can be adaptively enhanced to ensure sufficient braking force can be provided even over a very short distance to avoid a collision.

[0072] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for determining the longitudinal target acceleration of a vehicle, wherein step S103 may include the following steps: Step S103_1: Determine the initial proportional coefficient based on the vehicle speed type to which the current vehicle speed belongs.

[0073] In this embodiment, the system first classifies vehicle speeds into multiple consecutive speed ranges (e.g., 10km / h-15km / h, 15km / h-20km / h, 20km / h-25km / h). Each speed range corresponds to a speed type; for example, 10km / h-15km / h corresponds to low speed, 15km / h-20km / h to medium speed, and 20km / h-25km / h to high speed. An initial proportional coefficient is predefined for each speed type, with higher speeds corresponding to smaller initial proportional coefficients. Therefore, based on the speed range the current vehicle speed falls into, the speed type is determined, and the initial proportional coefficient corresponding to that speed type is used as the initial proportional coefficient for the current speed.

[0074] Step S103_2: Adjust the initial proportional coefficient based on at least one of the following: current vehicle speed deviation, road length, current remaining available distance of the target cruise scenario, whether the vehicle is in the starting phase, and acceleration deviation, to obtain the adjusted proportional coefficient.

[0075] In this embodiment, the initial proportional coefficient corresponding to the current vehicle speed is then corrected in real time based on a variety of dynamic factors.

[0076] Specifically, this includes: 1) Adjusting the initial proportional coefficient based on the absolute value of the current vehicle speed deviation. When the absolute value of the current vehicle speed deviation is too large, the initial proportional coefficient is increased to accelerate the convergence speed of the error; when the absolute value of the current vehicle speed deviation is small, the initial proportional coefficient is maintained or decreased to avoid overshoot; 2) Adjusting the initial proportional coefficient based on the road length (remaining path length). When the remaining path length is long, driving comfort is prioritized, so the initial proportional coefficient is appropriately reduced to reduce acceleration steps; when the remaining path length is short and the vehicle is in the cruising phase, the initial proportional coefficient can be appropriately increased to ensure task efficiency; 3) Adjusting the initial proportional coefficient based on the current remaining available distance of the target cruising scenario (the target cruising scenario is the cruising scenario corresponding to the target vehicle speed at the current moment in cruise mode). When the current remaining available distance is too small, the initial proportional coefficient is increased to enhance braking or deceleration response; 4) Determining whether the vehicle is in the starting phase. If so, the initial proportional coefficient is significantly increased to improve the starting speed; 5) Introducing acceleration deviation (the deviation between the comfort acceleration of two adjacent historical moments). If the acceleration changes drastically, the initial proportional coefficient is reduced to suppress oscillations. These adjustment logics work together to adjust the initial proportional coefficient, resulting in the adjusted proportional coefficient, thereby achieving the purpose of adaptive PI control.

[0077] In addition, this application also adjusts the initial proportional coefficient based on the current remaining available distance of the target cruise scenario under extreme conditions (the target cruise scenario is the cruise scenario corresponding to the target vehicle speed at the current moment in cruise mode). Specifically, when the current remaining available distance is negative (indicating that the distance from the vehicle to the target location or obstacle is less than the safe distance, and the safety risk increases sharply), the initial proportional coefficient is significantly increased to enhance braking.

[0078] When the remaining available distance is positive, the specific calculation expression for the adjusted scaling factor is as follows: ,in, This is the adjusted scaling factor; This is the initial scaling factor; This is the vehicle speed deviation adjustment coefficient; This is a road length adjustment factor; This is the adjustment factor for the current remaining available distance. The larger the current remaining available distance, the larger the adjustment factor. Adjustment coefficients for the initial stage; This is the acceleration deviation adjustment factor. Optionally, at least one of these correction factors can be selected to participate in the adjustment of the initial proportional coefficient.

[0079] When the remaining available distance is negative, the specific calculation expression for the adjusted scaling factor is as follows: Optionally, at least one of these correction factors can be selected to participate in the adjustment of the initial scaling factor.

[0080] This is the braking enhancement coefficient, which is a progressive braking coefficient that gradually increases with the accumulation of braking activation time.

[0081] Step S103_3: Determine the current comfort acceleration based at least on the adjusted proportional coefficient and the current vehicle speed deviation.

[0082] In this embodiment, the current comfort acceleration is calculated using the deviation between the adjusted proportional coefficient obtained in step S103_2 and the current vehicle speed. The calculation expression is: ,in, Accelerate for current comfort.

[0083] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for determining the longitudinal target acceleration of a vehicle, wherein step S103_3 may include the following steps: Step S103_3_1: Determine the initial integral coefficient based on the vehicle speed type to which the current vehicle speed belongs.

[0084] In this embodiment, another alternative implementation for calculating the current comfort acceleration is as follows: Similar to proportional coefficients, this application predefines different initial integral coefficients for different vehicle speed types. Each vehicle speed type has its own predefined initial integral coefficient, with higher speeds corresponding to smaller initial integral coefficients. Therefore, based on the speed range within which the vehicle's current speed falls, the vehicle speed type is determined, and the initial integral coefficient corresponding to that speed type is used as the initial integral coefficient for the current speed.

[0085] Step S103_3_2: Based on the current vehicle speed deviation, query the correspondence between the vehicle speed deviation and the integral compensation coefficient, and determine the current integral compensation coefficient.

[0086] In this embodiment, the system incorporates a lookup table or function curve to describe the relationship between the magnitude of the vehicle speed deviation and the integral compensation coefficient. When the vehicle speed deviation is large, the integral action is suppressed; when the vehicle speed deviation approaches zero but a steady-state error exists, the integral compensation coefficient is increased to enhance the ability to eliminate the error. Based on the current vehicle speed deviation, the integral compensation coefficient corresponding to the current vehicle speed deviation is obtained by querying this correspondence in real time, and this integral compensation coefficient is used as the current integral compensation coefficient.

[0087] Step S103_3_3: Determine the cumulative integral amount for the current integral period based on the current integral compensation coefficient, integral period, current vehicle speed deviation, and cumulative integral amount for the previous integral period.

[0088] In this embodiment, the cumulative integral amount of the current integral period is calculated based on the current integral compensation coefficient, integral period, current vehicle speed deviation, and the cumulative integral amount of the previous integral period.

[0089] The formula for calculating the cumulative integral of the current integration period is:

[0090] in, This represents the accumulated points for the current scoring cycle. This represents the cumulative integral from the previous integration cycle. This represents the current vehicle speed deviation. For the integration period; This is the current integral compensation coefficient.

[0091] Step S103_3_4: Determine the current comfort acceleration based on the cumulative integral amount of the current integral cycle, the initial integral coefficient, the adjusted proportional coefficient, and the current vehicle speed deviation.

[0092] In this embodiment, the current comfort acceleration is calculated based on the cumulative integral of the current integral cycle, the initial integral coefficient, the adjusted proportional coefficient, and the current vehicle speed deviation. The specific calculation expression is as follows:

[0093] in, Accelerate for current comfort; This is the adjusted scaling factor; This represents the current vehicle speed deviation. These are the initial integration coefficients; This represents the integral accumulation for the current integral cycle. By introducing an adaptive proportional coefficient and a dynamically compensated integral coefficient, high-precision speed tracking and smooth acceleration control can be achieved.

[0094] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for determining the longitudinal target acceleration of a vehicle, wherein the method includes the following steps: Step S201: Determine the initial maximum acceleration based on the road length.

[0095] In this embodiment, and in another embodiment of this application, an adaptive constraint mechanism for maximum acceleration is added to optimize the control boundaries for long-distance cruising and short-distance parking.

[0096] Before calculating the target acceleration at the current moment in cruise mode, the remaining path length (road length) is first assessed. For long-distance AVP parking scenarios, the vehicle is allowed to operate at a larger maximum acceleration to improve traffic efficiency; for short-distance APA parking scenarios or when approaching the destination, the maximum acceleration is limited to ensure safety and comfort.

[0097] Based on the preset road length-maximum acceleration mapping table, and considering the remaining road length that the vehicle still needs to travel, the maximum acceleration corresponding to that road length is queried from the mapping table, and this maximum acceleration is determined as the current initial maximum acceleration.

[0098] Step S202: Determine the vehicle speed type coefficient based on the vehicle speed type to which the current vehicle speed belongs.

[0099] In this embodiment, a vehicle speed type coefficient is predefined for each vehicle speed type. The higher the vehicle speed, the larger the corresponding vehicle speed type coefficient. Therefore, based on the speed range in which the vehicle's current speed falls, the vehicle speed type to which the current speed belongs is determined, and then the vehicle speed type coefficient corresponding to that speed type is used as the vehicle speed type coefficient corresponding to the current speed.

[0100] For example, for high-speed cruising (>3m / s), the speed type coefficient is 1.0; for low-speed parking (<0.5m / s), the coefficient is corrected to 0.8 to prevent starting shock.

[0101] Step S203: Determine the vehicle speed deviation coefficient based on the current vehicle speed deviation; and determine the road slope coefficient based on the road slope.

[0102] In this embodiment, a dynamic correction factor is further introduced. A vehicle speed deviation coefficient is calculated based on the magnitude of the current speed deviation: the larger the current speed deviation, the smaller the vehicle speed deviation coefficient. This limits the acceleration output when the speed error is large, preventing further errors. Simultaneously, the current road slope information is obtained through the vehicle's built-in slope sensor. If it is a downhill section, acceleration is limited to prevent speeding due to gravity acceleration; if it is an uphill section, greater acceleration can be allowed to maintain climbing. Based on this, the vehicle speed deviation coefficient and the road slope coefficient are calculated respectively.

[0103] For example, if the current vehicle speed deviation is large (e.g., 1 m / s), the vehicle speed deviation coefficient is set to 0.9; if the road slope is detected to be -3% (downhill), the road slope coefficient is set to 0.7, and the upper limit of acceleration is forcibly reduced to adapt to the slope characteristics.

[0104] Step S204: Adjust the initial maximum acceleration based on at least one of the road gradient coefficient, vehicle speed deviation coefficient, and vehicle speed type coefficient to obtain the adjusted maximum acceleration.

[0105] In this embodiment, the initial maximum acceleration determined in step S201 is used as a benchmark, and is sequentially multiplied by various correction coefficients calculated in steps S202 and S203. Through this multi-dimensional weighted adjustment, an adjusted maximum acceleration adapted to the current specific working conditions is finally obtained. This value comprehensively reflects the influence of path length, velocity state, error conditions, and environmental slope, and is a dynamically changing control upper limit. The expression for calculating the maximum acceleration is: ,in, This is the initial maximum acceleration; For vehicle speed type coefficient; This is the vehicle speed deviation coefficient; This is the road gradient coefficient.

[0106] In this embodiment, for the calculated adjusted maximum acceleration, this application sets a calibrated upper limit value to constrain the adjusted maximum acceleration; that is, the calculated adjusted maximum acceleration cannot exceed the calibrated upper limit value. Specifically, in a parking scenario, when the vehicle is cruising towards the parking space, the calibrated upper limit value is a first upper limit value; when the vehicle has reached the parking space and begins to park, the calibrated upper limit value is a second upper limit value, and the first upper limit value is greater than the second upper limit value. In other words, a larger acceleration is allowed during cruising to improve driving efficiency, while the upper limit of acceleration is limited to a smaller value during actual parking to ensure safety and comfort.

[0107] For example, the initial maximum acceleration is 1.5 m / s². The vehicle speed type coefficient is 0.8, the deviation coefficient is 0.9, and the gradient coefficient is 1.0 (for flat roads). After adjustment, the maximum acceleration = 1.5 × 0.8 × 0.9 ≈ 1.08 m / s². This value is the maximum allowable acceleration limit at the current moment.

[0108] Step S205: Using the adjusted maximum acceleration as the upper limit, determine the target acceleration for the current moment in cruise mode from the current comfort acceleration and the current emergency braking acceleration.

[0109] In this embodiment, an absolute value limiting check is introduced based on the arbitration logic of the original step S105. The acceleration selected from comfort acceleration and emergency braking acceleration is compared with the adjusted maximum acceleration obtained in step S204. If the absolute value of the selected acceleration exceeds the upper limit, it is forcibly clamped to the adjusted maximum acceleration; otherwise, the original value is maintained. This process ensures that the final control command is always within the range allowed by the vehicle's dynamic capabilities and safety, preventing excessive acceleration shocks caused by algorithm calculation errors or extreme conditions, and ensuring that the vehicle does not exceed the safe acceleration limit.

[0110] In conjunction with the above embodiments, in one implementation, the present invention also provides a method for determining the longitudinal target acceleration of a vehicle, wherein the method includes the following steps: Step S301: When the target vehicle speed is zero and the vehicle is stationary in cruise mode at the current moment, the target acceleration in cruise mode at the current moment is limited to a first acceleration range, which is used to keep the vehicle stationary.

[0111] In this embodiment, the application further adds special processing logic for the parking state to ensure vehicle stability and prevent accidental movement when the vehicle is stationary. In cruise mode, when the target position is determined to have been reached (target speed = 0) and the wheel speed sensor confirms that the vehicle is actually completely stationary, the parking hold strategy is activated. At this time, the output of the target acceleration at the current moment is limited to a very small first acceleration range (e.g., [-0.1m / s², 0.1m / s²]) (i.e., the first acceleration range), or a reverse compensation torque is applied based on the slope information. The purpose of this range is to counteract any minor external forces that the vehicle may experience (such as road slope, wind resistance, or rolling tendency caused by uneven ground), ensuring the vehicle remains stationary and preventing rollback after automatic parking is completed.

[0112] For example, in a ramp parking scenario, the target vehicle speed has decreased to 0, and the sensors confirm the speed as 0 km / h. The system detects a 5% uphill slope and calculates the equilibrium acceleration required to maintain stillness to be approximately -0.2 m / s². The system limits the target acceleration to a first acceleration range near this value (e.g., -0.15 m / s² to -0.25 m / s²) to ensure the vehicle does not roll backward.

[0113] Step S302: When the distance between the vehicle and the target location or obstacle is less than a preset distance, limit the target acceleration at the current moment in cruise mode to not exceed the target acceleration at the previous moment.

[0114] In this embodiment, when the vehicle enters an area extremely close to the target (target location or obstacle) (e.g., less than 1m from the target location), to prevent the vehicle from undergoing a final acceleration and collision before stopping, this application executes special braking constraint logic. In this state, regardless of changes in the calculated values ​​of current comfort acceleration or emergency braking acceleration, the target acceleration at the current moment in cruise mode is limited to not exceeding the target acceleration value of the previous moment. If the currently calculated and selected acceleration value as the target acceleration at the current moment is larger than the previous moment (i.e., more inclined towards positive acceleration), then the target acceleration of the previous moment is forcibly taken as the target acceleration at the current moment; if it is a deceleration process, it is allowed to continue decreasing. This strategy ensures that at the end of the stop, only a deceleration trend or a zero acceleration trend is maintained, eliminating the risk of sudden acceleration before stopping.

[0115] For example, the vehicle is 0.5m from the target point, and the current calculated comfort acceleration is -1.0m / s² (forced acceleration), while the target acceleration at the previous moment was -0.8m / s². Since -1.0 < -0.8 (more negative), it does not violate the limit. If the current calculated value is +0.5m / s² (unexpected acceleration signal), while the previous value was -0.8m / s², the system determines that 0.5 > -0.8, triggers the limit, and forces an output of -0.8m / s². This ensures that there is no risk of collision due to a sudden increase in acceleration when approaching the stopping point.

[0116] In this embodiment, the method of this application includes two braking strategies: slow braking and emergency braking. Slow braking achieves smooth stopping through a progressive braking coefficient, which increases with the activation time, gradually decelerating the vehicle to a stop. Emergency braking employs a larger emergency braking coefficient to bring the vehicle to a rapid stop while limiting the minimum braking acceleration to avoid jerking caused by over-braking. Both modes utilize anti-acceleration-increase strategies to ensure the smoothness of the braking process.

[0117] Based on the same inventive concept, this application provides a system for determining the longitudinal target acceleration of a vehicle, such as... Figure 4 As shown, the system 400 includes: The first target vehicle speed determination module 401 is used to determine the target vehicle speed at the current moment for each of the various cruise scenarios when cruise mode is activated, based on the target distance, the current vehicle speed, and the pre-configured parameter values ​​for each of the various cruise scenarios. The target distance is the distance from the vehicle to the target location point or obstacle. The various cruise scenarios include at least two of the following: following vehicle scenario, yielding to vehicles scenario, and yielding to pedestrian scenario. The second target vehicle speed determination module 402 is used to determine the target vehicle speed at the current moment in the cruise mode based on the target vehicle speed at the current moment in each of the various cruise scenarios. The comfort acceleration determination module 403 is used to determine the current vehicle speed deviation based on the current vehicle speed and the target vehicle speed at the current moment in cruise mode, and to determine the current comfort acceleration based on the current vehicle speed deviation. Emergency braking acceleration determination module 403 is used to determine the current emergency braking acceleration based on the current vehicle speed and target distance; The target acceleration determination module 405 is used to determine the target acceleration at the current moment in cruise mode from the current comfort acceleration and the current emergency braking acceleration. The target acceleration at the current moment in cruise mode is used to control the longitudinal acceleration of the vehicle.

[0118] Optionally, the first target vehicle speed determination module 401 includes: The remaining available distance determination module is used to determine the current remaining available distance for various cruise scenarios when cruise mode is enabled, based on the target distance, current vehicle speed, and the pre-configured safe distance for each cruise scenario. The first target vehicle speed determination submodule is used to determine the target vehicle speed at the current moment for each of the various cruise scenarios based on the current vehicle speed, the pre-configured acceleration for each of the various cruise scenarios, and the current remaining available distance.

[0119] Optionally, the target acceleration determination module 405 includes: The safe distance determination module is used to determine the current safe distance based on the current vehicle speed; The emergency braking state determination module is used to determine the current state of emergency braking as active when the target distance is less than the current safe distance, and to determine the current state of emergency braking as inactive when the target distance is not less than the current safe distance. The first target acceleration determination module is used to determine the current emergency braking acceleration as the target acceleration at the current moment in cruise mode when the current emergency braking state is active and the current emergency braking acceleration is less than the current comfort acceleration. The second target acceleration determination module is used to determine the current comfort acceleration as the target acceleration at the current moment in cruise mode when the current state of emergency braking is deactivated, or when the current emergency braking acceleration is not less than the current comfort acceleration.

[0120] Optionally, the target acceleration determination module 405 includes: The data acquisition module is used to acquire the target acceleration at the previous moment when the current vehicle speed is greater than the vehicle speed threshold. The third target acceleration determination module is used to determine the target acceleration at the current moment in cruise mode based on the emergency braking filter coefficient, the current emergency braking acceleration, and the previous target acceleration when the current emergency braking state is active and the current emergency braking acceleration is less than the current comfort acceleration. The fourth target acceleration determination module is used to determine the target acceleration at the current moment in cruise mode based on the comfort filter coefficient, the current comfort acceleration, and the target acceleration at the previous moment, when the current emergency braking state is deactivated, or when the current emergency braking acceleration is not less than the current comfort acceleration. The comfort filter coefficient is less than the emergency braking filter coefficient.

[0121] Optionally, the emergency braking acceleration determination module 403 includes: The safe distance determination module is used to determine the current safe distance based on the current vehicle speed; The emergency braking coefficient determination module is used to determine the current emergency braking coefficient based on the distance difference between the current safe distance and the target distance. The emergency braking acceleration determination submodule is used to determine the current emergency braking acceleration based on the current vehicle speed, target distance, and current emergency braking coefficient.

[0122] Optional, the comfort acceleration determination module 403 includes: The initial proportional coefficient determination module is used to determine the initial proportional coefficient based on the vehicle speed type to which the current vehicle speed belongs. The adjusted proportional coefficient determination module is used to adjust the initial proportional coefficient based on at least one of the following: current vehicle speed deviation, road length, current remaining available distance of the target cruise scenario, whether the vehicle is in the starting phase, and acceleration deviation, to obtain the adjusted proportional coefficient. The target cruise scenario is the cruise scenario corresponding to the target vehicle speed at the current moment in cruise mode; the acceleration deviation is the deviation between the comfort acceleration of two adjacent historical moments. The comfort acceleration determination submodule is used to determine the current comfort acceleration based at least on the adjusted proportional coefficient and the current vehicle speed deviation.

[0123] Optional, comfort acceleration determination submodule, including: The initial integral coefficient determination module is used to determine the initial integral coefficient based on the vehicle speed type to which the current vehicle speed belongs. The integral compensation coefficient determination module is used to query the correspondence between the current vehicle speed deviation and the integral compensation coefficient based on the current vehicle speed deviation, and determine the current integral compensation coefficient. The integral accumulation determination module is used to determine the integral accumulation of the current integral period based on the current integral compensation coefficient, integral period, current vehicle speed deviation and integral accumulation of the previous integral period. The current comfort acceleration determination module is used to determine the current comfort acceleration based on the cumulative integral amount of the current integral cycle, the initial integral coefficient, the adjusted proportional coefficient, and the current vehicle speed deviation.

[0124] Optionally, the system 400 also includes: The initial maximum acceleration determination module is used to determine the initial maximum acceleration based on the road length. The vehicle speed type coefficient determination module is used to determine the vehicle speed type coefficient based on the vehicle speed type to which the current vehicle speed belongs. The vehicle speed deviation coefficient determination module is used to determine the vehicle speed deviation coefficient based on the current vehicle speed deviation. The road slope coefficient determination module is used to determine the road slope coefficient based on the road slope. The adjusted maximum acceleration determination module is used to adjust the initial maximum acceleration based on at least one of the road gradient coefficient, vehicle speed deviation coefficient, and vehicle speed type coefficient to obtain the adjusted maximum acceleration. The target acceleration determination module is used to determine the target acceleration at the current moment in cruise mode, based on the current comfort acceleration and the current emergency braking acceleration, with the adjusted maximum acceleration as the upper limit.

[0125] Optionally, the system 400 also includes: The first limiting module is used to limit the target acceleration in the current moment of cruise mode to a first acceleration range when the target vehicle speed is zero and the vehicle is stationary in cruise mode. The first acceleration range is used to keep the vehicle stationary. The second limiting module is used to limit the target acceleration at the current moment in cruise mode from not exceeding the target acceleration at the previous moment when the distance between the vehicle and the target location or obstacle is less than a preset distance.

[0126] It should be noted that, for the sake of simplicity, the method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments of this application are not limited to the described order of actions, because according to the embodiments of this application, some steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also understand that the embodiments described in the specification are all preferred embodiments, and the actions involved are not necessarily necessary for the embodiments of this application. As for the system embodiments, since they are basically similar to the method embodiments, the description is relatively simple; relevant details can be found in the descriptions of the method embodiments.

[0127] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on the differences from other embodiments. The same or similar parts between the various embodiments can be referred to each other.

[0128] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, embodiments of this application can take the form of entirely hardware embodiments, entirely software embodiments, or embodiments combining software and hardware aspects. Furthermore, embodiments of this application can take the form of computer program products implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0129] This application describes embodiments with reference to flowchart illustrations and / or block diagrams of methods, terminal devices (systems), and computer program products according to embodiments of this application. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing terminal device to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing terminal device, generate instructions for implementing the flowchart illustrations. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0130] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing terminal device to operate in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0131] These computer program instructions can also be loaded onto a computer or other programmable data processing terminal equipment, causing a series of operational steps to be performed on the computer or other programmable terminal equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable terminal equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0132] Although preferred embodiments of the present application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of the embodiments of the present application.

[0133] Finally, it should be noted that in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or terminal device that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or terminal device. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or terminal device that includes said element.

[0134] The present application provides a detailed description of a method and system for determining the longitudinal target acceleration of a vehicle. Specific examples have been used to illustrate the principles and implementation methods of the present application. The descriptions of the above embodiments are only for the purpose of helping to understand the method and its core ideas. At the same time, those skilled in the art will recognize that there will be changes in the specific implementation methods and application scope based on the ideas of the present application. Therefore, the content of this specification should not be construed as a limitation of the present application.

Claims

1. A method for determining the longitudinal target acceleration of a vehicle, characterized in that, include: When cruise mode is enabled, the target speed for each of the various cruise scenarios is determined based on the target distance, current vehicle speed, and pre-configured parameter values ​​for each cruise scenario. The target distance is the distance from the vehicle to the target location or obstacle. The various cruise scenarios include at least two of the following: following vehicle scenario, yielding to other vehicles scenario, and yielding to pedestrian scenario. Determine the target vehicle speed at the current moment under cruise mode based on the target vehicle speed at the current moment for each of the various cruise scenarios. Based on the current vehicle speed and the target vehicle speed at the current moment in cruise mode, determine the current vehicle speed deviation, and based on the current vehicle speed deviation, determine the current comfort acceleration; Determine the current emergency braking acceleration based on the current vehicle speed and target distance; The target acceleration at the current moment in cruise mode is determined from the current comfort acceleration and the current emergency braking acceleration. The target acceleration at the current moment in cruise mode is used to control the longitudinal acceleration of the vehicle.

2. The method for determining the longitudinal target acceleration of a vehicle according to claim 1, characterized in that, With cruise control enabled, the target speed for each of the various cruise scenarios is determined based on the target distance, current vehicle speed, and pre-configured parameter values ​​for each scenario, including: When cruise mode is enabled, the remaining available distance for each cruise scenario is determined based on the target distance, current vehicle speed, and the pre-configured safe distance for each cruise scenario. Based on the current vehicle speed, the pre-configured acceleration for each of the various cruise scenarios, and the current remaining available distance, determine the target vehicle speed for each of the various cruise scenarios at the current moment.

3. The method for determining the longitudinal target acceleration of a vehicle according to claim 1, characterized in that, Determine the target acceleration for the current moment in cruise mode from the current comfort acceleration and the current emergency braking acceleration, including: Determine the current safe distance based on the current vehicle speed; If the target distance is less than the current safe distance, the current state of emergency braking is set to active; if the target distance is not less than the current safe distance, the current state of emergency braking is set to deactivated. If the emergency braking is currently active and the current emergency braking acceleration is less than the current comfort acceleration, the current emergency braking acceleration will be determined as the target acceleration for the current moment in cruise mode. If the current state of emergency braking is deactivated, or if the current emergency braking acceleration is not less than the current comfort acceleration, the current comfort acceleration is determined as the target acceleration at the current moment in cruise mode.

4. The method for determining the longitudinal target acceleration of a vehicle according to claim 3, characterized in that, Determine the target acceleration for the current moment in cruise mode from the current comfort acceleration and the current emergency braking acceleration, including: If the current vehicle speed is greater than the vehicle speed threshold, obtain the target acceleration at the previous moment. If the emergency braking is currently active and the current emergency braking acceleration is less than the current comfort acceleration, the target acceleration for the current moment in cruise mode is determined based on the emergency braking filter coefficient, the current emergency braking acceleration, and the previous target acceleration. If the emergency braking is currently deactivated, or if the current emergency braking acceleration is not less than the current comfort acceleration, the target acceleration for the current moment in cruise mode is determined based on the comfort filter coefficient, the current comfort acceleration, and the target acceleration of the previous moment, with the comfort filter coefficient being less than the emergency braking filter coefficient.

5. The method for determining the longitudinal target acceleration of a vehicle according to claim 1, characterized in that, Based on the current vehicle speed and target distance, determine the current emergency braking acceleration, including: Determine the current safe distance based on the current vehicle speed; Determine the current emergency braking coefficient based on the difference between the current safe distance and the target distance; Determine the current emergency braking acceleration based on the current vehicle speed, target distance, and current emergency braking coefficient.

6. The method for determining the longitudinal target acceleration of a vehicle according to claim 1, characterized in that, Determine the current comfort acceleration based on the current vehicle speed deviation, including: Determine the initial proportional coefficient based on the vehicle speed type of the current vehicle speed; The initial proportional coefficient is adjusted based on at least one of the following: current speed deviation, road length, current remaining available distance of the target cruise scenario, whether the vehicle is in the starting phase, and acceleration deviation. The adjusted proportional coefficient is obtained. The target cruise scenario is the cruise scenario corresponding to the target vehicle speed at the current moment in cruise mode. The acceleration deviation is the deviation between the comfort acceleration of two adjacent historical moments. The current comfort acceleration should be determined based at least on the adjusted proportional coefficient and the current vehicle speed deviation.

7. The method for determining the longitudinal target acceleration of a vehicle according to claim 6, characterized in that, Determine the current comfort acceleration based at least on the adjusted proportional coefficient and the current vehicle speed deviation, including: Determine the initial integral coefficient based on the vehicle speed type of the current vehicle speed; Based on the current vehicle speed deviation, query the correspondence between the vehicle speed deviation and the integral compensation coefficient, and determine the current integral compensation coefficient; The cumulative amount of points in the current integration period is determined based on the current integration compensation coefficient, integration period, current vehicle speed deviation, and cumulative amount of points in the previous integration period. The current comfort acceleration is determined based on the accumulated points of the current integration cycle, the initial integration coefficient, the adjusted proportional coefficient, and the current vehicle speed deviation.

8. A method for determining the longitudinal target acceleration of a vehicle according to any one of claims 1-7, characterized in that, Also includes: Determine the initial maximum acceleration based on the road length; Determine the vehicle speed type coefficient based on the current vehicle speed type; Determine the vehicle speed deviation coefficient based on the current vehicle speed deviation; Determine the road slope coefficient based on the road gradient; The initial maximum acceleration is adjusted based on at least one of the road gradient coefficient, vehicle speed deviation coefficient, and vehicle speed type coefficient to obtain the adjusted maximum acceleration. Determine the target acceleration for the current moment in cruise mode from the current comfort acceleration and the current emergency braking acceleration, including: Using the adjusted maximum acceleration as the upper limit, the target acceleration for the current moment in cruise mode is determined from the current comfort acceleration and the current emergency braking acceleration.

9. A method for determining the longitudinal target acceleration of a vehicle according to any one of claims 1-7, characterized in that, Also includes: When the target vehicle speed is zero and the vehicle is stationary at the current moment in cruise mode, the target acceleration at the current moment in cruise mode is limited to a first acceleration range, which is used to keep the vehicle stationary. When the distance between the vehicle and the target location or obstacle is less than a preset distance, the target acceleration at the current moment in cruise mode is limited to not exceed the target acceleration at the previous moment.

10. A system for determining the longitudinal target acceleration of a vehicle, characterized in that, The system includes: The first target speed determination module is used to determine the target speed at the current moment for each of the various cruise scenarios when cruise mode is enabled, based on the target distance, current speed, and pre-configured parameter values ​​for each of the various cruise scenarios. The target distance is the distance from the vehicle to the target location or obstacle. The various cruise scenarios include at least two of the following: following vehicle scenario, yielding to other vehicles scenario, and yielding to pedestrian scenario. The second target vehicle speed determination module is used to determine the target vehicle speed at the current moment in cruise mode based on the target vehicle speed at the current moment in various cruise scenarios. The comfort acceleration determination module is used to determine the current vehicle speed deviation based on the current vehicle speed and the target vehicle speed at the current moment in cruise mode, and to determine the current comfort acceleration based on the current vehicle speed deviation. The emergency braking acceleration determination module is used to determine the current emergency braking acceleration based on the current vehicle speed and the target distance. The target acceleration determination module is used to determine the target acceleration at the current moment in cruise mode from the current comfort acceleration and the current emergency braking acceleration. The target acceleration at the current moment in cruise mode is used to control the longitudinal acceleration of the vehicle.

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