Vehicle speed control system, electronic device, vehicle, method and program product

Abstract

The present disclosure provides a vehicle speed control system, an electronic device, a vehicle, a vehicle speed control method, a storage medium and a program product. The system can execute: obtaining multiple planning time periods and constraint parameters corresponding to the vehicle's driving conditions, each planning time period including multiple planning time points; based on the constraint parameters, calculating the expected acceleration and expected jerk of the vehicle at each planning time point in each planning time period, and calculating the speed cost value corresponding to each planning time period based on the expected acceleration and expected jerk and the length of the planning time period; determining a target time period in each planning time period based on the size of the speed cost value corresponding to each planning time period; based on the constraint parameters, calculating the expected speed of the vehicle at each planning time point in the target time period, and fitting the target speed change curve based on the expected speed at each planning time point.

Description

Technical Field

[0001] The present disclosure relates to the field of computer technology, and more particularly to a vehicle speed control system, an electronic device, a vehicle, a vehicle speed control method, a storage medium, and a computer program product. Background Art

[0002] The vigorous development of autonomous driving technology is inseparable from the reasonable vehicle speed control ability. Efficient and stable speed control can not only ensure the safe operation of the vehicle, but also improve the comfort of the vehicle.

[0003] However, the current speed control method of autonomous driving can usually only control the speed change of the vehicle with a constant acceleration, and has poor flexibility. Although it can be used on highways with simple road conditions, using this method to control the speed of the vehicle in streets with relatively complex road conditions is prone to "sudden acceleration" and "sudden deceleration" control situations, and has poor adaptability to complex road conditions. Summary of the invention

[0004] In order to solve one of the above technical problems, the present disclosure provides a vehicle speed control system, an electronic device, a vehicle speed control method, a storage medium and a computer program product.

[0005] According to a first aspect of the present disclosure, a vehicle speed control system is provided. The vehicle speed control system includes a processor memory, wherein the memory stores a computer program. When the computer program is executed by the processor, the vehicle speed control system performs the following process: obtaining a plurality of planning time periods and constraint parameters corresponding to the vehicle's driving conditions, wherein each planning time period includes a plurality of planning time points, and the constraint parameters include at least one of a displacement constraint parameter, a speed constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter; based on the constraint parameters, calculating the expected acceleration and the expected jerk of the vehicle at each of the planning time points in each of the planning time periods, and calculating the expected acceleration and the expected jerk of the vehicle at each of the planning time points in each of the planning time periods; and calculating the expected acceleration and the expected jerk of the vehicle at each of the planning time points in each of the planning time periods. The speed cost value corresponding to each of the planned time periods is calculated based on the expected acceleration and the expected jerk and the length of the planned time period; a target time period is determined in each of the planned time periods based on the size of the speed cost value corresponding to each of the planned time periods; based on the constraint parameters, the expected speed of the vehicle at each of the planned time points in the target time period is calculated, and a target speed change curve is obtained based on the expected speed fitting at each of the planned time points; wherein the target speed change curve is used to control the speed of the vehicle in the driving condition, the driving condition represents the target speed and / or target displacement that the vehicle is expected to achieve, and the size of the speed cost value represents the smoothness of the speed change of the vehicle within the planned time period.

[0006] In an optional implementation manner, the displacement constraint parameters include: a starting point displacement, a process displacement and an end point displacement.

[0007] In an optional implementation manner, the speed constraint parameters include: maximum speed, minimum speed, starting speed, process speed and terminal speed.

[0008] In an optional implementation, the acceleration constraint parameters include: maximum acceleration, minimum acceleration, starting point acceleration, process acceleration and end point acceleration.

[0009] In an optional implementation, the jerk constraint parameters include: maximum jerk, minimum jerk, starting point jerk and end point jerk.

[0010] In an optional embodiment, the driving condition includes a first condition, a second condition and a third condition; the first condition represents the condition in which the vehicle reaches a target displacement after the planned time period; the second condition represents the condition in which the vehicle reaches a target speed and a target displacement after the planned time period; the third condition represents the condition in which the vehicle reaches a target speed after the planned time period; wherein the constraint parameters corresponding to the first condition and the second condition include the displacement constraint parameters, the speed constraint parameters, the acceleration constraint parameters and the jerk constraint parameters, and the constraint parameters corresponding to the third condition include the speed constraint parameters, the acceleration constraint parameters and the jerk constraint parameters.

[0011] In an optional implementation, when calculating the speed cost value corresponding to each planning time period based on the expected acceleration and the expected jerk at each planning time point of each planning time period and the duration of the planning time period, the speed control system of the vehicle executes: obtaining the planning time interval between two adjacent planning time points in each planning time period; for each planning time period, calculating a first sum of products based on the expected acceleration at each planning time point and the planning time interval; for each planning time period, calculating a second sum of products based on the expected jerk at each planning time point and the planning time interval; for each planning time period, calculating a square value of the duration based on the duration of the planning time period; for each planning time period, adding the first sum of products, the second sum of products, and the square value of the duration corresponding to the planning time period to obtain the speed cost value corresponding to the planning time period; wherein the first sum of products is the sum of the products of the squares of the expected acceleration at each planning time point and the planning time interval; and the second sum of products is the sum of the products of the squares of the expected jerk at each planning time point and the planning time interval.

[0012] In an optional embodiment, the driving conditions include multiple types. When obtaining multiple planned time periods and constraint parameters corresponding to the driving conditions of the vehicle, the speed control system of the vehicle executes: determining the current driving condition of the vehicle among the multiple driving conditions, and obtaining multiple planned time periods and constraint parameters corresponding to the current driving condition of the vehicle; or obtaining the corresponding multiple planned time periods and constraint parameters for each of the driving conditions of the vehicle.

[0013] According to a second aspect of the present disclosure, there is provided an electronic device, which is applied to a vehicle and includes a processor and a memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, the electronic device performs the following process: obtaining a plurality of planned time periods and constraint parameters corresponding to the vehicle's driving conditions, each of the planned time periods including a plurality of planned time points, the constraint parameters including at least one of a displacement constraint parameter, a speed constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter; based on the constraint parameters, calculating the expected acceleration and the expected jerk of the vehicle at each of the planned time points in each of the planned time periods, and calculating the expected acceleration and the expected jerk of the vehicle at each of the planned time points in each of the planned time periods; The speed and the expected acceleration and the length of the planned time period are used to calculate the speed cost value corresponding to each of the planned time periods; based on the size of the speed cost value corresponding to each of the planned time periods, a target time period is determined in each of the planned time periods; based on the constraint parameters, the expected speed of the vehicle at each of the planned time points in the target time period is calculated, and a target speed change curve is obtained based on the expected speed fitting at each of the planned time points; wherein the target speed change curve is used to control the speed of the vehicle in the driving condition, the driving condition represents the target speed and / or target displacement that the vehicle is expected to achieve, and the size of the speed cost value represents the smoothness of the speed change of the vehicle within the planned time period.

[0014] A third aspect of the present disclosure provides a vehicle, the vehicle comprising the electronic device according to any one embodiment of the present disclosure.

[0015] A fourth aspect of the present disclosure provides a vehicle speed control method, which includes: obtaining multiple planning time periods and constraint parameters corresponding to the vehicle's driving conditions, each of the planning time periods includes multiple planning time points, and the constraint parameters include at least one of a displacement constraint parameter, a speed constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter; based on the constraint parameters, calculating the expected acceleration and expected jerk of the vehicle at each of the planning time points in each of the planning time periods, and calculating the speed cost value corresponding to each of the planning time points based on the expected acceleration and the expected jerk at each of the planning time points in each of the planning time periods and the length of the planning time period; determining a target time period in each of the planning time periods based on the size of the speed cost value corresponding to each of the planning time periods; based on the constraint parameters, calculating the expected speed of the vehicle at each of the planning time points in the target time period, and fitting a target speed change curve based on the expected speed at each of the planning time points; wherein the target speed change curve is used to control the speed of the vehicle in the driving condition, the driving condition characterizes the target speed and / or target displacement that the vehicle is expected to achieve, and the size of the speed cost value characterizes the smoothness of the speed change of the vehicle in the planning time period.

[0016] A fifth aspect of the present disclosure provides a computer-readable storage medium having a computer program stored thereon. When the computer program is executed by a processor, the vehicle speed control method of any embodiment of the present disclosure is executed.

[0017] A sixth aspect of the present disclosure provides a computer program product, which includes a computer program. When the computer program is executed by a processor, the vehicle speed control method of any embodiment of the present disclosure is executed. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] The accompanying drawings illustrate exemplary embodiments of the present disclosure and together with the description serve to explain the principles of the present disclosure. These drawings are included to provide a further understanding of the present disclosure and are incorporated in and constitute a part of this specification.

[0019] Figure 1 It is a schematic diagram of a scenario in which a vehicle speed control system according to some embodiments of the present disclosure is applied to an electronic device of the vehicle.

[0020] Figure 2 The present invention is a flowchart of a vehicle speed control system according to some embodiments of the present invention for controlling the vehicle speed.

[0021] Figure 3 It is a schematic diagram of the planning time periods and planning time points of some embodiments of the present disclosure.

[0022] Figure 4 is a schematic diagram of the structure of a vehicle speed control system according to some embodiments of the present disclosure.

[0023] Figure 5 The present invention is a flowchart of a vehicle speed control system according to some embodiments of the present invention for controlling the vehicle speed.

[0024] Figure 6 It is a flowchart of a vehicle speed control method according to some embodiments of the present disclosure.

[0025] Figure 7 It is a flowchart of a vehicle speed control method according to some embodiments of the present disclosure.

[0026] Figure 8 It is a flowchart of a vehicle speed control method according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0027] The present disclosure is further described in detail below in conjunction with the accompanying drawings and implementations. It is understood that the specific implementations described herein are only used to explain the relevant content, rather than to limit the present disclosure. It should also be noted that, for ease of description, only the parts related to the present disclosure are shown in the accompanying drawings.

[0028] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in the present disclosure can be combined with each other. The technical solution of the present disclosure will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0029] Unless otherwise specified, the exemplary embodiments / embodiments shown will be understood as providing exemplary features of various details of some ways in which the technical concept of the present disclosure can be implemented in practice. Therefore, unless otherwise specified, the features of the various embodiments / embodiments can be combined, separated, interchanged and / or rearranged without departing from the technical concept of the present disclosure.

[0030] The use of cross-hatching and / or shading in the accompanying drawings is generally used to make the boundaries between adjacent components clear. As such, unless otherwise specified, the presence or absence of cross-hatching or shading does not convey or indicate any preference or requirement for the specific materials, material properties, dimensions, proportions, commonalities between the components shown, and / or any other characteristics, attributes, properties, etc. of the components. In addition, in the accompanying drawings, the sizes and relative sizes of the components may be exaggerated for clarity and / or descriptive purposes. When the exemplary embodiments can be implemented differently, the specific process sequence can be performed in a different order than described. For example, two successively described processes can be performed substantially simultaneously or in an order opposite to the described order. In addition, the same figure numbers represent the same components.

[0031] When a component is referred to as being "on" or "over," "connected to," or "coupled to" another component, the component may be directly on, directly connected to, or directly coupled to the other component, or intervening components may be present. However, when a component is referred to as being "directly on," "directly connected to," or "directly coupled to" another component, there are no intervening components. For this purpose, the term "connected" may refer to a physical connection, an electrical connection, etc., with or without intervening components.

[0032] The terms used herein are for the purpose of describing specific embodiments, and are not intended to be restrictive. As used herein, unless the context clearly indicates otherwise, the singular forms "one (kind, person)" and "(the)" are also intended to include plural forms. In addition, when the terms "comprise" and / or "include" and their variations are used in this specification, it is explained that there are stated features, integral bodies, steps, operations, parts, assemblies and / or their groups, but one or more other features, integral bodies, steps, operations, parts, assemblies and / or their groups are not excluded from existence or addition. It should also be noted that, as used herein, the terms "substantially", "approximately" and other similar terms are used as approximate terms and not as degree terms, so that they are used to explain the inherent deviations of the measured values, calculated values ​​and / or the values ​​provided that will be recognized by those of ordinary skill in the art.

[0033] The current speed control method of vehicle 1000 can usually only control the speed change of vehicle 1000 with a constant acceleration, and has poor flexibility. Although it can be used on highways with simple road conditions, using this method to control the speed of vehicle 1000 in blocks with relatively complex road conditions is prone to "sudden acceleration" and "sudden deceleration" control situations, and has poor adaptability to complex road conditions.

[0034] Based on the above problems, the present disclosure provides a speed control system 100 of a vehicle 1000 . Figure 1The application scenario of the speed control system 100 of the vehicle 1000 according to the embodiment of the present disclosure is shown, in which the speed control system 100 of the vehicle 1000 performs speed control of the vehicle 1000. In this application scenario, the speed control system 100 of the vehicle 1000 can be applied to the electronic device 200 of the vehicle 1000.

[0035] See also Figure 2 , Figure 2 A schematic flowchart showing the speed control system 100 of the vehicle 1000 according to the embodiment of the present disclosure performing speed control of the vehicle 1000 is shown.

[0036] During the process of automatic driving, the vehicle 1000 determines the current driving condition of the vehicle 1000 according to the road environment in which it is located or the instructions input by humans. The driving condition represents the target speed and / or target displacement that the vehicle 1000 is expected to achieve. For example, the current road environment is a highway, and there are no obstacles in front of the vehicle 1000. Based on the current road environment, the vehicle 1000 determines that the current driving condition is a cruising condition, which represents that the vehicle 1000 is expected to reach a constant target speed.

[0037] After determining the current driving condition of the vehicle 1000, the speed control system 100 of the vehicle 1000 can obtain the constraint parameters corresponding to the driving condition. The constraint parameters include at least one of a displacement constraint parameter, a speed constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter. Jerk is a physical quantity that describes the speed of acceleration change, and represents the rate of change of acceleration over time.

[0038] For example, the current scenario is that the current speed of the vehicle 1000 is 80 km / h, the current driving condition of the vehicle 1000 is the cruising condition, and the target speed of the cruising condition is 100 km / h. During the speed control process in which the speed of the vehicle 1000 changes from 80 km / h to 100 km / h, it is considered that the vehicle 1000 travels from the starting point at a speed of 80 km / h and a certain acceleration to the end point, and the speed at the end point is 100 km / h and the acceleration is 0. During this process, there is no restriction on the initial displacement and final displacement of the vehicle 1000, and there is no displacement constraint parameter; during the speed control process, the starting speed of the vehicle 1000 is 80 km / h, and the terminal speed is 100 km / h. The speed at the next moment is affected by the speed at the previous moment, and there are restrictions on the maximum and minimum driving speeds on the highway, and these restrictions constitute the speed constraint parameters of the vehicle 1000; during the speed control process, the starting acceleration of the vehicle 1000 is a certain acceleration, and the terminal acceleration is 0. The acceleration at the next moment is affected by the acceleration at the previous moment, and the maximum and minimum acceleration of the vehicle 1000 are restricted based on the hardware performance and comfort index of the vehicle 1000, and these restrictions constitute the acceleration constraint parameters to which the vehicle 1000 is subject; during the speed control process, the starting jerk and terminal jerk of the vehicle 1000 are both 0, and the hardware performance and comfort index of the vehicle 1000 constitute restrictions on the maximum and minimum jerk of the vehicle 1000, and these restrictions constitute the jerk constraint parameters to which the vehicle 1000 is subject.

[0039] Furthermore, after determining the current driving condition of the vehicle 1000, the speed control system 100 obtains a plurality of planned time periods corresponding to the driving condition. The planned time period represents the estimated time required for the vehicle 1000 to change from the current speed and / or displacement to the expected target speed and / or target displacement. For example, when the current speed of the vehicle 1000 is 80 km / h, it is determined that the current driving condition of the vehicle 1000 is a cruising condition, and the target speed of the cruising condition is 100 km / h. The planned time period in this scenario is the estimated time required for the vehicle 1000 to change from 80 km / h to 100 km / h.

[0040] The speed control system 100 of the vehicle 1000 can calculate the speed change curve corresponding to any planned time period based on the constraint parameters corresponding to the driving conditions. The speed change curve reflects the change in the speed of the vehicle 1000 planned to meet the current driving conditions in the corresponding planned time period. The speed change curve can be used by the speed control system 100 to control the speed of the vehicle 1000. For example, based on the change in the speed of the vehicle 1000 in the speed change curve, the jerk of the vehicle 1000 is changed at a specific moment in the planned time period, so that the acceleration and speed of the vehicle 1000 change accordingly. In this way, the speed control system 100 of the vehicle 1000 can control the speed of the vehicle 1000 to illustrate various complex road conditions.

[0041] For each planned time period, the corresponding speed change curve can be calculated respectively; each speed change curve can be used as the basis for the speed control system 100 of the vehicle 1000 to control the speed of the vehicle 1000. In each planned time period and the speed change curves corresponding to each planned time period, a relatively optimal speed change curve can be obtained as the basis for the speed control system 100 of the vehicle 1000 to actually control the speed of the vehicle 1000. Among them, the relatively optimal speed change curve is the curve with the smoothest speed change among the various speed change curves. In the curve with the smoothest speed change, there are relatively few changes in which the speed increases or decreases suddenly. In this way, based on the relatively optimal speed change curve, the speed change of the vehicle 1000 is controlled, and it is not easy to have the control situation of "sudden acceleration" or "sudden deceleration", and it has better adaptability to complex road conditions.

[0042] The speed control system 100 of the vehicle 1000 of the present disclosure can calculate the speed cost value of the speed change curve, and measure the smoothness of the speed change curve by the speed cost value of the speed change curve to determine a relatively optimal speed change curve.

[0043] Specifically, the magnitude of the speed cost value represents the smoothness of the speed change of the vehicle 1000 within the planning time period. The smaller the speed cost value, the smoother the speed change of the vehicle 1000 within the planning time period; the larger the speed cost value, the less smooth the speed change of the vehicle 1000 within the planning time period.

[0044] Based on the constraint parameters and a planning time period, the speed cost corresponding to the planning time period can be calculated. The speed cost corresponding to the planning time period can represent the smoothness of the speed change curve corresponding to the planning time period relative to the speed change curve corresponding to the planning time period. Assuming that the speed cost is recorded as cost, the speed cost cost can be calculated by the following formula 1.

[0045] Formula 1: cost = costopt +ω t ·T 2

[0046] Among them, T 2 Characterizes the square of the planning time period. ω t The weight that represents the square of the planning time period. opt Characterizes the constraint cost value and reflects the influence of constraint parameters on the smoothness of the speed change curve.

[0047] The speed control system 100 of the vehicle 1000 of the present disclosure can calculate the constraint cost value cost based on the assumption of local linearization and the calculation formula of the quadratic programming problem. opt .

[0048] Please combine Figure 3 Specifically, when calculating the speed change curve, n planning time points are determined in the planning time period T, denoted as t i , i = 1, 2, 3, ..., n. Two adjacent planning time points t i There is a fixed time interval between them, which is recorded as dt. In this way, each planning time point t i The instantaneous velocity, instantaneous acceleration, and instantaneous jerk can be calculated using the calculation formulas for linear velocity, linear acceleration, and linear jerk, respectively. At each planning time point t i The instantaneous acceleration of the previous planning time point t i-1 The instantaneous acceleration of each planning time point t i The instantaneous speed is the same as the previous planning time point t i-1 The instantaneous acceleration is related to the instantaneous jerk. For each planning time point t within the planning time period T i By fitting the instantaneous speed of the vehicle 1000, a speed change curve can be obtained, which corresponds to the planned time period T and represents the change of the speed of the vehicle 1000 within the planned time period T.

[0049] At the same time, when the speed change curve passes through each planning time point t i Based on the instantaneous speed fitting, the speed cost value cost corresponding to the speed change curve, the constraint cost value cost opt The calculation of each planning time point t i The instantaneous acceleration is related to the instantaneous jerk and represents the planning time point t i The constraint relationship between instantaneous acceleration and instantaneous jerk on velocity change.

[0050] Based on this, the constraint cost opt The specific calculation can be obtained by the following formula 2.

[0051] Formula 2:

[0052] Among them, j i Representation of planning time point t i The instantaneous acceleration, ω j Characterizes the weight of the sum of squared accelerations. i Representation of planning time point t i The instantaneous acceleration, ω a Represents the weight of the sum of squared accelerations. dt represents the time points t between two adjacent planning points i The time interval between.

[0053] Under different driving conditions, the acceleration a i and jerk j t The value of is subject to different constraints and can be calculated using the constraint parameters corresponding to the driving condition.

[0054] Assume that the current driving condition of the vehicle 1000 is a cruising condition, in which the vehicle 1000 is expected to reach a certain target speed from the current speed.

[0055] like Figure 3 As shown, assuming that under cruising conditions, it is estimated that the vehicle 1000 takes 5 seconds, 6 seconds or 7 seconds to reach the target speed, 5 seconds, 6 seconds and 7 seconds are three different planning time periods respectively. Figure 3 It indicates that the corresponding speed cost value is calculated when 5 seconds is used as the planning time period.

[0056] During the calculation, n planning time points are determined within the planning time period. The larger the value of n, that is, the more planning time points, the more accurate the calculation of the speed change curve and speed cost value corresponding to the planning time period; the smaller the value of n, that is, the fewer the number of planning time points, the higher the calculation efficiency of the speed change curve and speed cost value corresponding to the planning time period. The value of n can be a fixed value, or it can take different values ​​based on the length of the planning time period, and there is no restriction here. For example, the number of n is twice the length of the planning time period (in seconds) plus 1 more. When the planning time period is 5 seconds, the value of n is 11.

[0057] After determining n planned time points, the time interval dt between every two adjacent planned time points can be determined. The time interval dt can be calculated using the following formula 3.

[0058] Formula 3:

[0059] In the case of planning time period T = 5, n = 11, the time interval

[0060] When calculating the speed cost corresponding to the planned time period T, it is necessary to calculate the speed cost of each planned time point t i The acceleration a i and jerk j i In the cruising condition, the vehicle 1000 is subject to the following constraints: upper and lower limit constraints, endpoint constraints, and continuity constraints.

[0061] The upper and lower limit constraints refer to the upper and lower limits of the acceleration and jerk of the vehicle 1000 constrained by the performance of the vehicle 1000. Among them, the performance of the vehicle 1000 includes the hardware acceleration capability of the vehicle 1000, the physical limitations of the acceleration actuator of the vehicle 1000, the acceleration and jerk limitations specified by the comfort index of the vehicle 1000, etc., which are not listed here one by one. The upper and lower limit constraints specifically specify that the acceleration of the vehicle 1000 needs to satisfy greater than or equal to the minimum acceleration, and less than or equal to the maximum acceleration; and specify that the jerk of the vehicle 1000 needs to satisfy greater than or equal to the minimum jerk, and less than or equal to the maximum jerk. When the driving condition is the cruising condition, the upper and lower limit constraints of the cruising condition can be specifically shown as shown in Formula 4.

[0062] Formula 4:

[0063] Among them, a min Characterizes the minimum acceleration, a max Characterizes the maximum acceleration, j min Characterizes the minimum jerk, j max Characterizes the maximum jerk.

[0064] The endpoint constraint refers to the restrictions on the speed, acceleration, and jerk of the vehicle 1000 at the start and end times of the driving condition. The start and end times of the driving condition refer to the start and end times of the planned time period corresponding to the driving condition, respectively.

[0065] At the starting point of the driving condition, the speed, acceleration, and jerk of the vehicle 1000 are the actual speed, acceleration, and jerk of the vehicle 1000 when entering the driving condition, and these parameters can be detected by the sensors of the vehicle 1000. At the end point of the driving condition, the speed, acceleration, and jerk of the vehicle 1000 should meet the expected speed, acceleration, and jerk corresponding to the driving condition. When the driving condition is a cruising condition, the endpoint constraints of the cruising condition can be specifically shown in Formulas 5 and 6.

[0066] Formula 5:

[0067] Among them, v1 represents the starting speed, v crepresents the real-time speed of the vehicle 1000 at the starting point of the cruising condition, a1 represents the starting acceleration, a c j1 represents the real-time acceleration of the vehicle 1000 at the starting point of the cruising condition, and j1 represents the starting point jerk. The speed control system 100 of the vehicle 1000 controls the speed and acceleration of the vehicle 1000 by regulating the jerk of the vehicle 1000. At the starting point of the cruising condition, the speed control system 100 of the vehicle 1000 has not yet performed speed control, so the starting point acceleration j1=0.

[0068] Formula 6:

[0069] Among them, v n Represents the terminal speed, which is the nth time point in the planning time period, v t Characterizes the target speed that the vehicle 1000 is expected to reach in the cruising condition, a n Characterizes the terminal acceleration, j n Characterizes the terminal jerk. At the end of the cruising condition, the expectation for the vehicle 1000 is to reach the target speed v t , and maintain the target speed v t , so the terminal acceleration a that the vehicle 1000 is expected to reach at the end of the cruising condition is n and the terminal jerk j n Both are 0.

[0070] The continuity constraint refers to the constraint imposed on the vehicle 1000 at any planned time point between the starting point and the end point, that is, at any planned time point between the first planned time point and the nth planned time point. The speed control system 100 of the vehicle 1000 disclosed in the present invention calculates the speed and acceleration of the vehicle 1000 at each planned time point other than the endpoints (the starting point and the end point) based on the local linearization assumption. Specifically, at any planned time point other than the endpoints, the changes in the speed and acceleration of the vehicle 1000 are regarded as changes in the speed and acceleration corresponding to the linear displacement, and the speed formula for linear speed change driving is used to calculate the speed and acceleration of the vehicle 1000. When the driving condition is a cruising condition, the continuity constraint of the cruising condition can be specifically shown as Formula 7.

[0071] Formula 7:

[0072] Among them, v i Characterizes the speed at the i-th planning time point, v i+1 Represents the speed at the i+1th planning time point, a i Characterizes the acceleration at the i-th planning time point, a i+1 Represents the acceleration at the i+1th planning time point, j irepresents the acceleration at the i-th planning time point, and dt represents the time interval between two adjacent planning time points.

[0073] Combining the constraints of Formula 4, Formula 5, Formula 6 and Formula 7 above, we can construct a quadratic programming problem to solve the speed v of vehicle 1000 at the i-th planning time point: i , acceleration a i and jerk j i . For each planning time point in the planning time period, the speed v i By fitting, a speed change curve corresponding to the planned time period can be obtained, which represents the expected speed change of the vehicle 1000 in the planned time period to meet the constraint condition of the end point.

[0074] The speed control system 100 of the vehicle 1000 can control the speed change of the vehicle 1000 in the planned time period based on the speed change curve. For example, the speed control system 100 controls the speed of the vehicle 1000 so that the actual speed v of the vehicle 1000 at the i-th planned time point in the planned time period is si and the calculated speed v at the i-th planning time point i The speed control system 100 controls the speed of the vehicle 1000 in a manner that may include controlling the traction and / or braking force of the vehicle 1000 to change the acceleration of the vehicle 1000 , thereby controlling the speed of the vehicle 1000 .

[0075] Furthermore, the speed control system 100 of the vehicle 1000 can control the acceleration of the vehicle 1000 so that the actual acceleration a of the vehicle 1000 at the i-th planned time point in the planned time period is si and the calculated acceleration a at the i-th planning time point i The same, so that the actual speed v of vehicle 1000 at the i-th planning time point in the planning time period si and the calculated speed v at the i-th planning time point i same.

[0076] Further, when the speed control system 100 of the vehicle 1000 changes the acceleration of the vehicle 1000 by controlling the traction force and / or braking force of the vehicle 1000, the increase / decrease range of the traction force and / or braking force at the i-th planning time point in the planning time period is equal to the calculated acceleration j at the i-th planning time point. i In direct proportion to the acceleration j i When it is a positive number, the acceleration j i The larger the jerk j is, the greater the increase in the traction force of the vehicle 1000 controlled by the speed control system 100 is; iThe smaller the jerk j is, the smaller the increase in the traction force of the vehicle 1000 controlled by the speed control system 100 is. i When it is a negative number, the acceleration j i The larger the jerk j is, the greater the increase in the braking force of the vehicle 1000 controlled by the speed control system 100 is; i The smaller the value is, the smaller the increase in the braking force of the vehicle 1000 controlled by the speed control system 100 is.

[0077] The speed v of each planning time point in the planning time period i and acceleration a i Substituting formula 1 and formula 2 for calculation, we can get the speed cost value cost corresponding to the planned time period, that is, the speed cost value cost corresponding to the speed change curve corresponding to the same planned time period. The speed cost value cost represents the smoothness of the speed change curve.

[0078] Assuming that the cruising condition is under operation, the constraint conditions (constraint parameters) of the cruising condition are obtained, and three different planning time periods of 5 seconds, 6 seconds and 7 seconds are obtained, which are recorded as T5, T6 and T7 respectively, and the respective planning time points of the planning time periods T5, T6 and T7 are obtained. The speed change curve and speed cost value corresponding to the planning time period T5 are recorded as curve 5 and cost5 respectively, the speed change curve and speed cost value corresponding to the planning time period T6 are recorded as curve 6 and cost6 respectively, and the speed change curve and speed cost value corresponding to the planning time period T7 are recorded as curve 7 and cost7 respectively.

[0079] In one example, the speed change curves and speed cost values ​​corresponding to different planned time periods T5, T6 and T7 can be calculated respectively according to the constraints, and the speed change curve with the smallest speed cost value can be selected as the planned target speed change curve, which is applied to the speed control system 100 of the vehicle 1000 to control the speed of the vehicle 1000 in a cruising condition.

[0080] In one example, in order to reduce the amount of calculation and save computing resources, before calculating the speed change curve corresponding to the planning time period according to the constraint conditions, the speed cost values ​​corresponding to the different planning time periods T5, T6 and T7 can be calculated first, the minimum speed cost value is determined as the target cost value, the planning time period corresponding to the target cost value is recorded as the target time period, and then the target speed change curve is calculated according to the target time period corresponding to the target cost value, and the target speed change curve is used as the planning result and applied to the speed control system 100 of the vehicle 1000 to control the speed change of the vehicle 1000 in the cruising condition. For example, cost6 is the minimum speed cost value, then the speed change curve of the planning time period T6 is calculated according to the constraint conditions of the cruising condition, and the obtained curve 6 is used as the target speed change curve to be applied to the speed control system 100 of the vehicle 1000 to control the speed of the cruising condition.

[0081] In summary, the speed control system 100 disclosed in the present invention can plan the expected speed change of the vehicle 1000 based on the formal operating condition of the vehicle 1000 when the road condition is relatively complex and the vehicle 1000 may adopt one of a variety of operating conditions as the driving condition, and obtain the relatively smoothest target speed change curve. Based on the target speed change curve, the speed of the vehicle 1000 in the driving condition can be controlled to avoid the control situations of "sudden acceleration" and "sudden deceleration" to adapt to various complex road conditions.

[0082] See also Figure 4 , Figure 4 1 is a schematic diagram of the structure of the speed control system 100 of the vehicle 1000 provided in an embodiment of the present disclosure. The speed control system 100 of the vehicle 1000 includes a processor 10 and a memory 20, and the memory 20 stores a computer program. When the computer program is executed by the processor 10, the speed control system 100 of the vehicle 1000 performs the following process:

[0083] Acquire multiple planning time periods and constraint parameters corresponding to the driving conditions of the vehicle 1000, each planning time period including multiple planning time points;

[0084] Based on the constraint parameters, the expected acceleration and the expected jerk of the vehicle 1000 at each planning time point in each planning time period are calculated, and based on the expected acceleration and the expected jerk at each planning time point in each planning time period and the length of the planning time period, the speed cost value corresponding to each planning time period is calculated;

[0085] Based on the magnitude of the speed cost value corresponding to each planning time period, a target time period is determined in each planning time period;

[0086] Based on the constraint parameters, the expected speed of the vehicle 1000 at each planned time point in the target time period is calculated, and the target speed variation curve is obtained based on the expected speed fitting at each planned time point.

[0087] The driving condition represents the target speed and / or target displacement that the vehicle 1000 is expected to reach. In one example, the vehicle 1000 is preset with a plurality of different driving conditions, and the vehicle 1000 can judge the road environment in which it is located based on the data such as speed, acceleration, positioning information, and vehicle distance information collected by the sensor, and determine the current driving condition of the vehicle 1000. Alternatively, a corresponding instruction can be manually input into the speed control system 100 of the vehicle 1000, so that the speed control system 100 of the vehicle 1000 obtains the driving condition of the vehicle 1000 based on the corresponding instruction.

[0088] The planning time period is the estimated time required for the vehicle 1000 to reach the expected target speed and / or target displacement in the driving condition. Each driving condition corresponds to at least two different planning time periods.

[0089] The planned time period corresponding to the driving condition may be a pre-configured time period. For example, a certain driving condition may be pre-configured with planned time periods T5, T6, and T7, which are 5 seconds, 6 seconds, and 7 seconds, respectively.

[0090] The planned time period corresponding to the driving condition may be a time sampled near a reference time based on a reference time calculated in real time based on the driving condition of the vehicle 1000 and the current driving parameters. The current driving parameters of the vehicle 1000 may include one or more of the current driving speed and current acceleration of the vehicle 1000. For example, a driving condition characterizes that the target displacement expected to be achieved by the vehicle 1000 is 10m, the current driving speed of the vehicle 1000 is 2m / s, and the current acceleration is 0. The above parameters are input into the deceleration model of the vehicle 1000 for simulation calculation, and the reference time obtained is 5 seconds. The preset sampling time interval is 1 second, and the number of samples is 3. According to the above conditions, the planned time periods T4, T5 and T6 can be sampled, which are 4 seconds, 5 seconds and 6 seconds respectively.

[0091] Each planning time period includes multiple planning time points. The number of planning time points can be a fixed value, or a different number of planning time points can be taken based on the length of the planning time period. There is no limitation here.

[0092] The constraint parameters include at least one of a displacement constraint parameter, a speed constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter. The constraint parameters of different driving conditions are obtained based on the constraint conditions of different driving conditions. For example, assuming that a certain driving condition represents that the vehicle 1000 is expected to reach a certain target displacement and target speed, the constraint conditions of the condition include the starting displacement limit and the end displacement limit, the starting speed limit and the end speed limit, the starting acceleration limit and the end acceleration limit, the starting jerk limit and the end jerk limit of the vehicle 1000 in the driving condition. At the same time, based on the software and hardware performance of the vehicle 1000, the speed, acceleration, and jerk of the vehicle 1000 have minimum and maximum value restrictions. Moreover, when the speed of vehicle 1000 changes within the planned time period, the acceleration at a later time point is affected by the acceleration and jerk at a previous time point, the speed at a later time point is affected by the speed, acceleration and jerk at the previous time point, and the displacement at a later time point is affected by the displacement, speed, acceleration and jerk at the previous time point, that is, the displacement, speed, acceleration and jerk at a later time point are subject to corresponding restrictions.

[0093] The constraints corresponding to different driving conditions may represent different restrictions. For example, assuming that a certain driving condition represents that the vehicle 1000 is expected to reach a certain target speed, the displacement of the vehicle 1000 in this condition is not restricted, and the constraint parameters of this condition include speed constraint parameters, acceleration constraint parameters, and jerk constraint parameters.

[0094] The magnitude of the speed cost value represents the smoothness of the speed change of the vehicle 1000 in the planning time period. The target cost value is determined from the speed cost values ​​corresponding to each planning time period, that is, the speed cost value that meets the required smoothness is found.

[0095] The target speed variation curve is used to control the speed of the vehicle 1000 in driving conditions.

[0096] The speed control system 100 of the vehicle 1000 can calculate the corresponding speed cost value and speed change curve for a planning time period based on the constraint parameters corresponding to the driving condition. The speed control system 100 of the vehicle 1000 disclosed in the present invention first calculates the corresponding speed cost value for each planning time period, and determines the target time period in each planning time period based on the size of the speed cost value. The smoothness represented by the target cost value is the ideal speed change smoothness under the driving condition. At this time, the target cost value uniquely corresponds to a planning time period. The speed control system 100 of the vehicle 1000 calculates the corresponding speed change curve for the planning time period corresponding to the target cost value based on the constraint parameters corresponding to the driving condition, which is recorded as the target speed change curve. The smoothness of the speed change of the target speed change curve is the smoothness represented by the target cost value. In this way, the speed control system 100 of the vehicle 1000 can obtain a target speed change curve with an ideal speed change smoothness, so as to control the speed of the vehicle 1000 in the driving condition based on the target speed change curve, and avoid the control situation of "sudden acceleration" and "sudden deceleration" to adapt to various complex road conditions.

[0097] In an optional embodiment, the jerk constraint parameters include: maximum jerk, minimum jerk, start jerk and end jerk. The start and end point refer to the start time and end time of the planned time period, respectively. The start jerk and end point jerk are the jerks of the vehicle 1000 at the start time and end time of the planned time period, respectively.

[0098] In one example, the speed control system 100 of the vehicle 1000 has not yet controlled the speed and acceleration of the vehicle 1000 to change at the beginning of the time period, and the jerk of the vehicle 1000 is 0 at this time; the speed control system 100 of the vehicle 1000 has completed the control of the speed and acceleration of the vehicle 1000 at the end of the time period, and the speed and acceleration of the vehicle 1000 no longer change, and the jerk of the vehicle 1000 is 0 at this time.

[0099] In one example, the start time of the planning time period is the time at which the first planning time point is located; the end time of the planning time period is the time at which the nth planning time point is located. In other words, the starting jerk defines the value of the jerk at the first planning time point, and the ending jerk defines the value of the jerk at the nth planning time point.

[0100] The maximum jerk and the minimum jerk are the upper and lower limits of the jerk based on the acceleration and deceleration performance of the hardware and software of the vehicle 1000 and the comfort index of the vehicle 1000, that is, there is a minimum step length and a maximum step length for the increase or decrease of the acceleration of the vehicle 1000. The expected jerk at the second planning time point, the nth planning time point, and each planning time point between the second planning time point and the n-1th planning time point should be greater than or equal to the minimum jerk and less than or equal to the maximum jerk.

[0101] In an optional embodiment, the acceleration constraint parameters include: maximum acceleration, minimum acceleration, starting acceleration, process acceleration and end acceleration. The starting acceleration and end acceleration are the accelerations of the vehicle 1000 at the beginning and end of the planned time period, respectively.

[0102] In one example, the start time of the planning time period is the time at which the first planning time point is located; the end time of the planning time period is the time at which the nth planning time point is located. In other words, the starting acceleration defines the value of the acceleration at the first planning time point, and the ending acceleration defines the value of the acceleration at the nth planning time point.

[0103] Process acceleration refers to the acceleration of the vehicle 1000 at any time between the start time and the end time of the planned time period. When the start time of the planned time period is the time at which the first planned time point is located, and the end time of the planned time period is the time at which the nth planned time point is located, the process acceleration includes the expected acceleration of the second planned time point, the nth planned time point, and each planned time point between the second planned time point and the n-1th planned time point. The expected acceleration of the latter planned time point is related to the expected acceleration of the previous planned time point, the expected jerk of the previous planned time point, and the time interval between two adjacent planned time points.

[0104] The maximum acceleration and the minimum acceleration are the upper and lower limits of the acceleration based on the acceleration and deceleration performance of the hardware and software of the vehicle 1000 and the comfort index of the vehicle 1000, that is, there is a minimum step length and a maximum step length for the increase or decrease of the speed of the vehicle 1000. The expected acceleration at the second planning time point, the nth planning time point, and each planning time point between the second planning time point and the n-1th planning time point should be greater than or equal to the minimum acceleration and less than or equal to the maximum acceleration.

[0105] In an optional implementation, the speed constraint parameters include: maximum speed, minimum speed, starting speed, process speed and terminal speed.

[0106] In one example, the start time of the planning time period is the time at which the first planning time point is located; the end time of the planning time period is the time at which the nth planning time point is located. In other words, the starting speed defines the speed value at the first planning time point, and the ending speed defines the speed value at the nth planning time point.

[0107] The process speed refers to the speed of the vehicle 1000 at any time between the start time and the end time of the planned time period. When the start time of the planned time period is the time at which the first planned time point is located, and the end time of the planned time period is the time at which the nth planned time point is located, the process speed includes the expected speeds at the second planned time point, the nth planned time point, and each planned time point between the second planned time point and the n-1th planned time point. The expected speed at the latter planned time point is related to the expected speed at the previous planned time point, the expected acceleration at the previous planned time point, the expected jerk at the previous planned time point, and the time interval between two adjacent planned time points.

[0108] The maximum speed is usually the maximum driving speed specified by the speed limit of the road. For example, if vehicle 1000 is driving on a road with a speed limit of 80 km / h, the maximum speed of vehicle 1000 in any driving condition is 80 km / h. The minimum speed is 0, which indicates that the planned speed is greater than or equal to 0, that is, only the forward movement or stop of vehicle 1000 is considered during the planning time period, and the reverse movement of vehicle 1000 is not considered. The expected acceleration at the second planning time point, the nth planning time point, and each planning time point between the second planning time point and the n-1th planning time point should be greater than or equal to the minimum acceleration and less than or equal to the maximum acceleration.

[0109] In an optional embodiment, the displacement constraint parameters include: starting displacement, process displacement and end displacement. When the driving condition represents the target displacement that the vehicle 1000 is expected to achieve, the starting displacement is 0, and the end displacement is equal to the target displacement, that is, the difference between the end displacement and the starting displacement is the target displacement, so that the vehicle 1000 is speed-controlled at the beginning of the planned time period and reaches the target displacement at the end of the planned time period. The process displacement is the displacement of the vehicle 1000 at the planned time point between the beginning and end of the planned time period, that is, the displacement of the i-th planned time point, i=2,...,n-1.

[0110] In an optional embodiment, the driving conditions of the vehicle 1000 include a first operating condition, a second operating condition and a third operating condition.

[0111] The first working condition represents the working condition in which the vehicle 1000 reaches the target displacement after a planned time period. For example, in an application scenario in which the vehicle 1000 is expected to reach the target parking position after a displacement of a known length, the speed control system 100 of the vehicle 1000 can plan the speed of the vehicle 1000 during this period based on the first working condition. The displacement of a known length is the target displacement.

[0112] For example, when the vehicle 1000 is 500m away from the parking place, the speed control system 100 of the vehicle 1000 takes 500m as the target displacement, obtains three planning time periods based on the first working condition, determines the target time period from the three planning time periods, calculates the target speed change curve of the vehicle 1000 in the target time period, and can inform the speed of the vehicle 1000 based on the target speed curve in the target time period. Assuming that the target time period is 20 seconds, the vehicle 1000 can decelerate according to the target speed curve, decelerate to a speed of 0 after 20 seconds, and the displacement reaches 500m.

[0113] The constraint parameters corresponding to the first working condition include displacement constraint parameters, velocity constraint parameters, acceleration constraint parameters and jerk constraint parameters.

[0114] Specifically, the jerk constraint parameter of the first working condition is shown in Formula 8:

[0115] Formula 8:

[0116] Where j1 is the expected acceleration at the first planning time point, that is, the starting point jerk; j n is the expected acceleration at the nth planning time point, i.e., the terminal jerk; j i is the expected acceleration at the i-th planning time point, i.e., the process jerk, i = 2, ..., n-1; j min is the minimum jerk; j max is the maximum jerk.

[0117] The acceleration constraint parameters of the first working condition are shown in Formula 9:

[0118] Formula 9:

[0119] Among them, a1 is the expected acceleration at the first planning time point, that is, the starting acceleration; a c is the actual acceleration at the first planning time point; a n is the expected acceleration at the nth planning time point, i.e., the terminal acceleration; a i is the expected acceleration at the i-th planning time point, i.e., process acceleration, i = 2, ..., n-1; dt is the time interval between two adjacent planning time points. min is the minimum acceleration; amax is the maximum acceleration.

[0120] The speed constraint parameters of the first working condition are shown in formula 10:

[0121] Formula 10:

[0122] Among them, v1 is the expected speed at the first planning time point, that is, the starting speed; v c is the actual speed at the first planning time point; v n is the expected speed at the nth planning time point, i.e., the terminal speed; v i is the expected speed at the i-th planning time point, i.e., the process speed, i = 2, ..., n-1; v min is the minimum speed, v min =0;v max is the maximum speed.

[0123] The displacement constraint parameters of the first working condition are shown in formula 11:

[0124] Formula 11:

[0125] Among them, s1 is the expected displacement at the first planning time point, that is, the displacement of the starting point; s n is the expected displacement at the nth planning time point, i.e., the end point displacement; s e is the target displacement; s i is the expected displacement at the i-th planning time point, that is, the process displacement, i=2,...,n-1.

[0126] The second operating condition represents the operating condition in which the vehicle 1000 reaches the target speed and the target displacement after a planned time period.

[0127] For example, there is a ramp section 100m ahead of the vehicle 1000, the speed limit of the ramp section is 40km / h, and the vehicle 1000 is expected to reach the entrance of the ramp section after driving 100m, and the vehicle speed reaches 40km / h. In this scenario, the speed control system 100 of the vehicle 1000 takes 100m as the target displacement and 40km / h as the target speed, and performs speed planning of the vehicle 1000 based on the second working condition.

[0128] The constraint parameters corresponding to the second working condition include displacement constraint parameters, velocity constraint parameters, acceleration constraint parameters and jerk constraint parameters.

[0129] Specifically, the jerk constraint parameter of the second working condition is the same as the jerk constraint parameter of the first working condition, as shown in the above formula 8, and will not be repeated here.

[0130] The acceleration constraint parameters of the second working condition are the same as those of the first working condition, as shown in Formula 9 above, and will not be repeated here.

[0131] The speed constraint parameters of the second working condition are shown in Formula 12:

[0132] Formula 12:

[0133] Among them, v f is the target speed.

[0134] The displacement constraint parameters of the second working condition are the same as those of the first working condition, as shown in Formula 9 above, and will not be repeated here.

[0135] The third operating condition represents the condition in which the vehicle 1000 reaches the target speed after a planned time period.

[0136] For example, the vehicle 1000 is expected to reach a driving speed of 80 km / h. In this scenario, the speed control system 100 of the vehicle 1000 takes 80 km / h as the target speed and performs speed planning of the vehicle 1000 based on the second operating condition.

[0137] The constraint parameters corresponding to the third working condition include a speed constraint parameter, an acceleration constraint parameter and a jerk constraint parameter.

[0138] Specifically, the jerk constraint parameter of the third working condition is the same as the jerk constraint parameter of the first working condition, as shown in the above formula 8, and will not be repeated here.

[0139] The acceleration constraint parameters of the third working condition are the same as those of the first working condition, as shown in Formula 9 above, and will not be repeated here.

[0140] The speed constraint parameters of the third working condition are the same as those of the second working condition, as shown in the above formula 12, and will not be repeated here.

[0141] The above three driving conditions are three examples of driving conditions of the vehicle 1000. The driving conditions of the vehicle 1000 are not limited to the above three examples of the first condition, the second condition and the third condition, and are not limited here.

[0142] After obtaining the driving condition of the vehicle 1000, the speed control system 100 of the vehicle 1000 obtains multiple planning time periods corresponding to the driving condition and constraint parameters corresponding to the driving condition. For any planning time period among the multiple planning time periods, the constraint parameters corresponding to the driving condition can be used to construct a quadratic programming problem, and the expected acceleration a at each planning time point (i.e., the i-th planning time point, i=1, ..., n) in the planning time period can be obtained by solving the problem. i and expected acceleration j iExpected acceleration a i and expected acceleration j i It is used to calculate the speed cost value corresponding to the planned time period, so as to determine the target time period in multiple planned time periods according to the size of the speed cost value in the subsequent steps. The speed control system 100 applied to the vehicle 1000 controls the speed of the vehicle 1000 in this driving condition.

[0143] In an optional embodiment, the speed control system 100 of the vehicle 1000 performs the following steps to obtain:

[0144] Obtain the planning time interval between two adjacent planning time points in each planning time period;

[0145] For each planning time period, a first product sum is calculated based on the expected acceleration at each planning time point and the planning time interval;

[0146] For each planning time period, calculating a second product sum based on the expected acceleration at each planning time point and the planning time interval;

[0147] For each planned time period, the square value of the duration is calculated based on the duration of the planned time period;

[0148] For each planning time period, the first product sum, the second product sum, and the square value of the duration corresponding to the planning time period are added together to obtain the speed cost value corresponding to the planning time period;

[0149] The first product sum is the sum of the products of the square of the expected acceleration at each planned time point and the planned time interval; the second product sum is the sum of the products of the square of the expected acceleration at each planned time point and the planned time interval.

[0150] Specifically, assuming that the speed cost is recorded as cost, the speed cost cost can be calculated by the above-mentioned formula 1 and formula 2. The above-mentioned formula 1 and formula 2 can be integrated into the following formula 13.

[0151] Formula 13:

[0152] in, represents the first product sum, and dt represents two adjacent planning time points t i The planning time interval between i Representation of planning time point t i The expected acceleration, ω j Characterizes the weight of the sum of squared jerk. Characterize the second product sum, a i Representation of planning time point t i The expected acceleration, ω aCharacterizes the weight of the sum of squared accelerations. 2 Characterizes the square value of the planning time period. ω t The weight that represents the square value of the duration of the planning time period.

[0153] In an optional embodiment, when obtaining the speed cost values ​​corresponding to each planning time period, the planning time period with the smallest speed cost value is determined as the target time period. In this way, it can be ensured that the target speed change curve obtained by the speed control system 100 of the vehicle 1000 in the target time period is the smoothest speed change curve among the speed change curves corresponding to each planning time period.

[0154] For the target time period, the constraint parameters corresponding to the driving condition can be used to construct a quadratic programming problem to solve the expected speed v at each planning time point (i.e., the i-th planning time point, i=1, ..., n) in the target time period. i , the expected speed v at each planning time point i The target speed variation curve can be obtained by fitting, and the target speed variation curve is applied to the speed control system 100 of the vehicle 1000 to control the speed of the vehicle 1000 in the driving condition.

[0155] In an optional implementation, if the expected speed v at each planning time point in the target time period cannot be solved based on the constraint parameters and the target time period, i , then the planning time period with the second smallest speed cost value is determined as the new target time period, replacing the old target time period for the expected speed v i Calculate. And so on, until we can solve the expected speed v i And the target time period with the minimum speed cost.

[0156] See also Figure 2 In an optional embodiment, when acquiring multiple planning time periods and constraint parameters corresponding to the driving condition of the vehicle 1000, the speed control system 100 of the vehicle 1000 executes:

[0157] The current driving condition of the vehicle 1000 is determined among multiple driving conditions, and multiple planning time periods and constraint parameters corresponding to the current driving condition of the vehicle 1000 are obtained.

[0158] For example, the vehicle 1000 is preset with a variety of different driving conditions, and the speed control system 100 of the vehicle 1000 can judge the road environment of the vehicle 1000 based on the data such as speed, acceleration, positioning information, and vehicle distance information collected by the sensor, and determine the current driving condition of the vehicle 1000. Alternatively, the speed control system 100 of the vehicle 1000 can be manually input with corresponding instructions, so that the speed control system 100 of the vehicle 1000 obtains the driving condition of the vehicle 1000 based on the corresponding instructions.

[0159] In this process, the target speed change curve acquired by the speed control system 100 of the vehicle 1000 is a speed change curve corresponding to the current driving condition of the vehicle 1000.

[0160] See also Figure 5 In another optional embodiment, when acquiring multiple planning time periods and constraint parameters corresponding to the driving condition of the vehicle 1000, the speed control system 100 of the vehicle 1000 executes:

[0161] For various driving conditions of the vehicle 1000, multiple corresponding planning time periods and constraint parameters are obtained respectively.

[0162] For example, the vehicle 1000 is preset with a first operating condition, a second operating condition and a third operating condition, and each driving operating condition corresponds to three planned time periods. The speed control system 100 of the vehicle 1000 calculates the three speed cost values ​​corresponding to the three planned time periods corresponding to the first operating condition based on the constraint parameters corresponding to the first operating condition; calculates the three speed cost values ​​corresponding to the three planned time periods corresponding to the second operating condition based on the constraint parameters corresponding to the second operating condition; calculates the three speed cost values ​​corresponding to the three planned time periods corresponding to the third operating condition based on the constraint parameters corresponding to the third operating condition; and finally determines the planned time period corresponding to the smallest speed cost value among the nine speed cost values ​​as the target time period. Assuming that the target time period is the planned time period corresponding to the first operating condition, the target speed change curve corresponding to the target time period is calculated based on the constraint parameters corresponding to the first operating condition. In this way, the smoothest target speed change curve in the current environment can be obtained based on the various driving operating conditions preset by the vehicle 1000.

[0163] See also Figure 1 The embodiment of the present disclosure further provides an electronic device 200, which is applied to the vehicle 1000 and includes a processor 10 and a memory 20, wherein the memory 20 stores a computer program. When the computer program is executed by the processor 10, the electronic device 200 performs the following process:

[0164] Acquire multiple planning time periods and constraint parameters corresponding to the driving conditions of the vehicle 1000, each planning time period includes multiple planning time points, and the constraint parameters include at least one of a displacement constraint parameter, a speed constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter;

[0165] Based on the constraint parameters, the expected acceleration and the expected jerk of the vehicle 1000 at each planning time point in each planning time period are calculated, and based on the expected acceleration and the expected jerk at each planning time point in each planning time period and the length of the planning time period, the speed cost value corresponding to each planning time period is calculated;

[0166] Based on the magnitude of the speed cost value corresponding to each planning time period, a target time period is determined in each planning time period;

[0167] Based on the constraint parameters, the expected speed of the vehicle 1000 at each planned time point in the target time period is calculated, and the target speed change curve is obtained based on the expected speed fitting at each planned time point.

[0168] Among them, the target speed change curve is used to control the speed of the vehicle 1000 in the driving condition. The driving condition represents the target speed and / or target displacement that the vehicle 1000 is expected to achieve, and the size of the speed cost value represents the smoothness of the speed change of the vehicle 1000 within the planned time period.

[0169] The principle of solving the problem by the electronic device 200 in the embodiment of the present disclosure is similar to that of the speed control system 100 of any vehicle 1000 in the embodiment of the present disclosure, and the repeated parts are not repeated here.

[0170] See also Figure 1 The embodiment of the present disclosure further provides a vehicle 1000 , the vehicle 1000 includes an electronic device 200 according to the embodiment of the present disclosure, and the electronic device 200 is used to control the speed of the vehicle 1000 .

[0171] Based on the same inventive concept, the embodiment of the present disclosure also provides a speed control method of vehicle 1000 corresponding to the speed control system 100 of vehicle 1000. Since the principle of solving the problem by the speed control method of vehicle 1000 in the embodiment of the present disclosure is similar to the speed control system 100 of the above-mentioned vehicle 1000 in the embodiment of the present disclosure, the implementation of the method can refer to the implementation of the device, and the repeated parts will not be repeated.

[0172] Figure 6 is a flow chart of a speed control method of a vehicle 1000 according to some embodiments of the present disclosure. Figure 6 , the speed control method M100 of the vehicle 1000 provided in the present disclosure may include step S110, step S120, step S130 and step S140.

[0173] S110: Acquire multiple planned time periods and constraint parameters corresponding to the driving conditions of the vehicle 1000.

[0174] Wherein, each planning time period includes a plurality of planning time points, and the constraint parameters include at least one of a displacement constraint parameter, a velocity constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter;

[0175] S120: Based on the constraint parameters, calculate the expected acceleration and expected jerk of the vehicle 1000 at each planning time point in each planning time period, and calculate the speed cost value corresponding to each planning time period based on the expected acceleration and expected jerk at each planning time point in each planning time period and the length of the planning time period.

[0176] S130: Determine a target time period in each planned time period based on the speed cost value corresponding to each planned time period.

[0177] S140: Based on the constraint parameters, the expected speed of the vehicle 1000 at each planned time point in the target time period is calculated, and a target speed variation curve is obtained based on the expected speed fitting at each planned time point.

[0178] Among them, the target speed change curve is used to control the speed of the vehicle 1000 in the driving condition. The driving condition represents the target speed and / or target displacement that the vehicle 1000 is expected to achieve, and the size of the speed cost value represents the smoothness of the speed change of the vehicle 1000 within the planned time period.

[0179] See also Figure 7 In some implementations, step S120 includes step S121, step S122, step S123, step S124, and step S125.

[0180] S121: Obtain the planned time interval between two adjacent planned time points in each planned time period.

[0181] S122: For each planned time period, a first product sum is calculated based on the expected acceleration at each planned time point and the planned time interval.

[0182] S123: For each planned time period, a second product sum is calculated based on the expected acceleration at each planned time point and the planned time interval.

[0183] S124: For each planned time period, a square value of the duration is calculated based on the duration of the planned time period.

[0184] S125: For each planned time period, the first product sum, the second product sum, and the square value of the duration corresponding to the planned time period are added together to obtain a speed cost value corresponding to the planned time period.

[0185] The first product sum is the sum of the products of the square of the expected acceleration at each planned time point and the planned time interval; the second product sum is the sum of the products of the square of the expected acceleration at each planned time point and the planned time interval.

[0186] See also Figure 8 In some implementations, step S110 includes step S111 or step S112.

[0187] S111: Determine the current driving condition of the vehicle 1000 among multiple driving conditions, and obtain multiple planning time periods and constraint parameters corresponding to the current driving condition of the vehicle 1000.

[0188] S112: For various driving conditions of the vehicle 1000, a plurality of corresponding planning time periods and constraint parameters are obtained respectively.

[0189] The disclosed embodiment also provides a computer-readable storage medium, in which execution instructions are stored, and when the execution instructions are executed by the processor 10, they are used to implement the above-mentioned method. "Readable storage medium" can be any device that can contain, store, communicate, propagate or transmit programs for use with an instruction execution system, device or equipment or in combination with these instruction execution systems, devices or equipment. More specific examples of readable storage media include the following: an electrical connection portion (electronic device) having one or more wirings, a portable computer disk box (magnetic device), a random access memory 20 (RAM), a read-only memory 20 (ROM), an erasable and editable read-only memory 20 (EPROM or flash memory 20), an optical fiber device, and a portable read-only memory 20 (CDROM), etc.

[0190] The embodiments of the present disclosure also provide a computer program product, including a computer program / instruction, which, when executed by the computer program / instruction processor 10, implements the question answering method provided in the embodiments of the present disclosure.

[0191] The method in the embodiment of the present disclosure can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer programs or instructions. When the computer program or instruction is loaded and executed on a computer, the process or function of the present application is executed in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, a network device, a user device, a core network device, an OAM or other programmable device.

[0192] The computer program or instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer program or instructions may be transmitted from one website, computer, server 110 or data center to another website, computer, server 110 or data center by wired or wireless means. The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server 110, data center, etc. that integrates one or more available media. The available medium may be a magnetic medium, such as a floppy disk, a hard disk, or a magnetic tape; it may also be an optical medium, such as a digital video disk; it may also be a semiconductor medium, such as a solid-state drive. The computer-readable storage medium may be a volatile or non-volatile storage medium, or may include both volatile and non-volatile types of storage media.

[0193] In the description of this specification, the description with reference to the terms "one embodiment / method", "some embodiments / methods", "example", "specific example", or "some examples" etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment / method or example are included in at least one embodiment / method or example of the present application. In this specification, the schematic representations of the above terms are not necessarily the same embodiment / method or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments / methods or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments / methods or examples described in this specification and the features of the different embodiments / methods or examples, unless they are contradictory.

[0194] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In the description of this application, the meaning of "plurality" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined.

[0195] Those skilled in the art should understand that the above embodiments are only for the purpose of clearly illustrating the present disclosure and the technical solutions of the present disclosure, rather than limiting them. The protection scope of the present disclosure is not limited thereto. Although the present disclosure is described in detail with reference to the above embodiments, those skilled in the art should understand that any person skilled in the art who is familiar with the present technical field can still modify the technical solutions recorded in the above embodiments within the technical scope disclosed in the present disclosure or can easily think of changes, or make equivalent replacements for some of the technical features therein; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present disclosure, and should be included in the protection scope of the present disclosure. Therefore, the protection scope of the present disclosure shall be based on the protection scope of the claims.

Claims

1. A vehicle speed control system, characterized in that: The invention comprises a processor memory, wherein the memory stores a computer program, and when the computer program is executed by the processor, the speed control system of the vehicle performs the following process: Acquire multiple planning time periods and constraint parameters corresponding to the driving conditions of the vehicle, each of the planning time periods includes multiple planning time points, and the constraint parameters include at least one of a displacement constraint parameter, a speed constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter; Based on the constraint parameters, the expected acceleration and the expected jerk of the vehicle at each of the planned time points in each of the planned time periods are calculated, and based on the expected acceleration and the expected jerk at each of the planned time points in each of the planned time periods and the length of the planned time period, the speed cost value corresponding to each of the planned time periods is calculated; Determining a target time period in each of the planned time periods based on the magnitude of the speed cost value corresponding to each of the planned time periods; Based on the constraint parameters, the expected speed of the vehicle at each of the planned time points in the target time period is calculated, and a target speed change curve is obtained based on the expected speed fitting at each of the planned time points; The target speed change curve is used to control the speed of the vehicle in the driving condition, the driving condition represents the target speed and / or target displacement that the vehicle is expected to achieve, and the speed cost value represents the smoothness of the speed change of the vehicle in the planned time period; When calculating the speed cost value corresponding to each planning time period based on the expected acceleration and the expected jerk at each planning time point of each planning time period and the duration of the planning time period, the speed control system of the vehicle executes: Obtaining a planned time interval between two adjacent planned time points in each planned time period; For each of the planned time periods, calculating a first product sum based on the expected acceleration at each of the planned time points and the planned time interval; For each of the planned time periods, calculating a second product sum based on the expected jerk at each of the planned time points and the planned time interval; For each of the planned time periods, calculating a square value of the duration based on the duration of the planned time period; For each of the planned time periods, add the first product sum, the second product sum, and the square value of the duration corresponding to the planned time period to obtain the speed cost value corresponding to the planned time period; The first product sum is the sum of the products of the square of the expected acceleration at each of the planned time points and the planned time interval; the second product sum is the sum of the products of the square of the expected acceleration at each of the planned time points and the planned time interval.

2. The vehicle speed control system according to claim 1, characterized in that: The displacement constraint parameters include: starting point displacement, process displacement and end point displacement; The speed constraint parameters include: maximum speed, minimum speed, starting speed, process speed and terminal speed; The acceleration constraint parameters include: maximum acceleration, minimum acceleration, starting point acceleration, process acceleration and end point acceleration; The jerk constraint parameters include: maximum jerk, minimum jerk, starting point jerk and end point jerk.

3. The vehicle speed control system according to claim 1, characterized in that: The driving conditions include a first condition, a second condition and a third condition; The first operating condition represents the operating condition in which the vehicle reaches the target displacement after the planned time period; The second operating condition represents the operating condition in which the vehicle reaches the target speed and the target displacement after the planned time period; The third operating condition represents the operating condition in which the vehicle reaches the target speed after the planned time period; Among them, the constraint parameters corresponding to the first working condition and the second working condition include the displacement constraint parameter, the velocity constraint parameter, the acceleration constraint parameter and the jerk constraint parameter, and the constraint parameters corresponding to the third working condition include the velocity constraint parameter, the acceleration constraint parameter and the jerk constraint parameter.

4. The vehicle speed control system according to claim 1, characterized in that: The driving conditions include multiple types. When obtaining multiple planning time periods and constraint parameters corresponding to the driving conditions of the vehicle, the speed control system of the vehicle executes: Determining the current driving condition of the vehicle among the multiple driving conditions, and obtaining a plurality of planning time periods and constraint parameters corresponding to the current driving condition of the vehicle; or For each of the driving conditions of the vehicle, a plurality of corresponding planning time periods and constraint parameters are obtained respectively.

5. An electronic device, characterized in that: The electronic device is applied to a vehicle and includes a processor and a memory, wherein the memory stores a computer program. When the computer program is executed by the processor, the electronic device performs the following process: Acquire multiple planning time periods and constraint parameters corresponding to the driving conditions of the vehicle, each of the planning time periods includes multiple planning time points, and the constraint parameters include at least one of a displacement constraint parameter, a speed constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter; Based on the constraint parameters, the expected acceleration and the expected jerk of the vehicle at each of the planned time points in each of the planned time periods are calculated, and based on the expected acceleration and the expected jerk at each of the planned time points in each of the planned time periods and the length of the planned time period, the speed cost value corresponding to each of the planned time periods is calculated; Determining a target time period in each of the planned time periods based on the magnitude of the speed cost value corresponding to each of the planned time periods; Based on the constraint parameters, the expected speed of the vehicle at each of the planned time points in the target time period is calculated, and a target speed change curve is obtained based on the expected speed fitting at each of the planned time points; The target speed change curve is used to control the speed of the vehicle in the driving condition, the driving condition represents the target speed and / or target displacement that the vehicle is expected to achieve, and the speed cost value represents the smoothness of the speed change of the vehicle in the planned time period; When calculating the speed cost value corresponding to each planning time period based on the expected acceleration and the expected jerk at each planning time point of each planning time period and the duration of the planning time period, the speed control system of the vehicle executes: Obtaining a planned time interval between two adjacent planned time points in each planned time period; For each of the planned time periods, calculating a first product sum based on the expected acceleration at each of the planned time points and the planned time interval; For each of the planned time periods, calculating a second product sum based on the expected jerk at each of the planned time points and the planned time interval; For each of the planned time periods, calculating a square value of the duration based on the duration of the planned time period; For each of the planned time periods, add the first product sum, the second product sum, and the square value of the duration corresponding to the planned time period to obtain the speed cost value corresponding to the planned time period; The first product sum is the sum of the products of the square of the expected acceleration at each of the planned time points and the planned time interval; the second product sum is the sum of the products of the square of the expected acceleration at each of the planned time points and the planned time interval.

6. A vehicle, characterized in that: The vehicle comprises the electronic device as claimed in claim 5.

7. A vehicle speed control method, characterized in that: include: Acquire multiple planning time periods and constraint parameters corresponding to the driving conditions of the vehicle, each of the planning time periods includes multiple planning time points, and the constraint parameters include at least one of a displacement constraint parameter, a speed constraint parameter, an acceleration constraint parameter, and a jerk constraint parameter; Based on the constraint parameters, the expected acceleration and the expected jerk of the vehicle at each of the planned time points in each of the planned time periods are calculated, and based on the expected acceleration and the expected jerk at each of the planned time points in each of the planned time periods and the length of the planned time period, the speed cost value corresponding to each of the planned time periods is calculated; Determining a target time period in each of the planned time periods based on the magnitude of the speed cost value corresponding to each of the planned time periods; Based on the constraint parameters, the expected speed of the vehicle at each of the planned time points in the target time period is calculated, and a target speed change curve is obtained based on the expected speed fitting at each of the planned time points; The target speed change curve is used to control the speed of the vehicle in the driving condition, the driving condition represents the target speed and / or target displacement that the vehicle is expected to achieve, and the speed cost value represents the smoothness of the speed change of the vehicle in the planned time period; When calculating the speed cost value corresponding to each planning time period based on the expected acceleration and the expected jerk at each planning time point of each planning time period and the duration of the planning time period, the speed control system of the vehicle executes: Obtaining a planned time interval between two adjacent planned time points in each planned time period; For each of the planned time periods, calculating a first product sum based on the expected acceleration at each of the planned time points and the planned time interval; For each of the planned time periods, calculating a second product sum based on the expected jerk at each of the planned time points and the planned time interval; For each of the planned time periods, calculating a square value of the duration based on the duration of the planned time period; For each of the planned time periods, add the first product sum, the second product sum, and the square value of the duration corresponding to the planned time period to obtain the speed cost value corresponding to the planned time period; The first product sum is the sum of the products of the square of the expected acceleration at each of the planned time points and the planned time interval; the second product sum is the sum of the products of the square of the expected acceleration at each of the planned time points and the planned time interval.

8. A readable storage medium, characterized in that: The readable storage medium stores a computer program, which is used to implement the method according to claim 7 when executed by a processor.

9. A computer program product, characterized in that The computer program product comprises a computer program, which is used to implement at least the method according to claim 7 when executed by a processor.

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