A processing method for controlling brake percentage

Abstract

The embodiment of the present application relates to a kind of processing methods of controlling brake percentage, the method comprises: obtaining planning speed, planning acceleration, control acceleration, pitch angle, real-time vehicle speed and driving gear mark;According to pitch angle, uphill and downhill acceleration identification is carried out;According to driving gear mark, planning acceleration, planning speed and real-time vehicle speed, whether it is confirmed to enter parking mode;If it is confirmed to enter parking mode, according to driving gear mark, real-time vehicle speed and uphill and downhill acceleration, target acceleration identification of parking mode is carried out;If it is confirmed not to enter parking mode, according to control acceleration and uphill and downhill acceleration, target acceleration identification of non-parking mode is carried out;According to real-time vehicle speed and target acceleration, brake percentage is obtained by inquiring first corresponding relation table.It can be divided into two stages of high-speed buffer brake and low-speed heavy brake in brake process, improve passenger comfort;Acceleration compensation of uphill and downhill acceleration can prevent the occurrence of hill slide.

Description

Technical Field

[0001] This invention relates to the field of data processing technology, and in particular to a method for controlling the percentage of braking force. Background Technology

[0002] The autonomous driving system includes working modules such as a positioning module, a planning module, a chassis module, and a control module. Among them, the positioning module can output the vehicle's real-time Euler angles (roll angle, pitch angle, yaw angle) pose and real-time vehicle speed; the planning module is used to plan the vehicle's driving speed and acceleration; the chassis module is used to provide feedback on the vehicle's real-time speed; the control module includes a longitudinal controller and a lateral controller, wherein the longitudinal controller is used to estimate the longitudinal acceleration / deceleration based on the outputs of the positioning module, planning module, and chassis module, and output the corresponding control acceleration (the control acceleration is greater than 0 during acceleration and less than 0 during deceleration).

[0003] When an autonomous driving system controls a vehicle to decelerate and brake, the conventional approach is to directly use the control acceleration, which is less than 0, output by the longitudinal controller as the target acceleration. Then, it queries a table that reflects the correspondence between real-time vehicle speed, target acceleration, and braking percentage, and controls the opening and closing of the vehicle's brake pedal based on the braking percentage obtained from the query.

[0004] However, in practical applications, we have found some problems with this conventional approach: 1) Some longitudinal controllers do not consider the gravitational acceleration component (also known as uphill / downhill acceleration) caused by the pitch angle of the vehicle's position when predicting control acceleration. Therefore, if the vehicle is on a slope (i.e., the pitch angle is not 0) when it is about to stop, it is easy for the vehicle to roll back on the slope, affecting vehicle safety; 2) In order to reduce the probability of rolling back, some longitudinal controllers simply output a large reverse control acceleration when the vehicle is about to stop. This can easily lead to excessive braking, affecting passenger comfort; 3) Some vehicles have a starting idle speed, that is, the vehicle speed gradually increases from 0 to about 5 km / h without pressing the accelerator or brake. In order to counteract this idle acceleration, some longitudinal controllers simply output a fixed reverse control acceleration. This fixed acceleration solution may also lead to either excessive braking affecting passenger comfort or insufficient braking causing the vehicle to roll back. Summary of the Invention

[0005] The purpose of this invention is to address the shortcomings of existing technologies by providing a method, electronic device, and computer-readable storage medium for controlling the percentage of braking force. First, the corresponding uphill / downhill acceleration is calculated based on the pitch angle output by the positioning module. Then, based on the vehicle gear position indicator, the planned speed and planned acceleration output by the planning module, and the real-time vehicle speed output by the positioning module or chassis module, it is determined whether to enter a parking mode. If parking mode is confirmed, it further judges whether the real-time vehicle speed is lower than a preset threshold. If it is not lower than the preset threshold, a braking acceleration parameter with a relatively small absolute value is set; if it is lower than the preset threshold, a braking acceleration parameter with a relatively large absolute value is set. The uphill / downhill acceleration is then used to adjust the obtained braking acceleration parameter. The system performs compensation to obtain the compensated acceleration parameters, and estimates the estimated acceleration parameters based on the target acceleration at the previous moment and the preset acceleration step size. When the driving gear is marked as D, the maximum value of the compensated acceleration parameter and the estimated acceleration parameter is taken as the target acceleration output; when the driving gear is marked as R, the minimum value of the compensated acceleration parameter and the estimated acceleration parameter is taken as the target acceleration output. If it is confirmed that the vehicle has not entered the parking mode, the control acceleration output by the control module is compensated using uphill and downhill acceleration, and the compensation result is taken as the target acceleration output. After obtaining the target acceleration output, the autonomous driving system looks up the corresponding braking percentage according to the real-time vehicle speed and the target acceleration. This invention allows for the braking process to be divided into two stages—high-speed gentle braking and low-speed heavy braking—based on the judgment of whether the real-time vehicle speed is below a preset threshold. This solves the problem of excessive braking that is common in conventional technical solutions, improves passenger comfort, and prevents vehicles with idling speed from rolling back or braking too suddenly when starting. Furthermore, by using acceleration compensation operations for uphill and downhill acceleration, it solves the problem of rolling back on slopes that is common in conventional technical solutions, thereby improving vehicle driving safety.

[0006] To achieve the above objectives, a first aspect of the present invention provides a method for controlling the braking percentage, the method comprising:

[0007] Obtain the planning velocity v at time k plan Planning acceleration a plan Controlling acceleration a control Pitch angle θ, real-time vehicle speed v vehicle and driving gear markings; the driving gear markings include D gear markings and R gear markings;

[0008] Based on the pitch angle θ, the uphill and downhill accelerations are identified and corresponding uphill and downhill accelerations a are generated. offset ;

[0009] Based on the vehicle gear position indicator and the planned acceleration a plan The planned speed vplan and the real-time vehicle speed v vehicle Confirm whether to enter parking mode;

[0010] If it is confirmed that parking mode has been entered, then based on the driving gear indicator and the real-time vehicle speed v vehicle and the acceleration a of the uphill and downhill slopes offset Target acceleration identification in parking mode generates target acceleration a at time k. target,k ;

[0011] If it is confirmed that the parking mode has not been entered, then according to the control acceleration a... control and the acceleration a of the uphill and downhill slopes offset Target acceleration identification in non-stop mode generates target acceleration a at time k. target,k ;

[0012] Query a preset first correspondence table reflecting the relationship between real-time vehicle speed, target acceleration, and braking percentage, and match the first vehicle speed range field in the first correspondence table with the real-time vehicle speed v. vehicle The first acceleration range field matches the target acceleration a. target,k The first braking percentage field of the first matching record is extracted as the braking percentage at the current time k; the first matching table includes multiple first matching records; the first matching record includes the first vehicle speed range field, the first acceleration range field, and the first braking percentage field.

[0013] Preferably, the step of identifying and generating corresponding uphill and downhill accelerations a based on the pitch angle θ is described. offset Specifically, it includes:

[0014] The corresponding uphill / downhill acceleration a is calculated based on the pitch angle θ and gravitational acceleration g. offset a offset = -sinθ*g; When the pitch angle θ is greater than 0, it is the downhill pitch angle, and the corresponding uphill and downhill acceleration a offset For downhill acceleration, a offset <0; When the pitch angle θ is less than 0, it is the uphill pitch angle, and the corresponding uphill / downhill acceleration a offset For uphill acceleration, a offset >0.

[0015] Preferably, the planned velocity v at the time of acquisition k plan Planning acceleration a plan Controlling acceleration a control Pitch angle θ, real-time vehicle speed v vehicle Before the gear position indicator, the method further includes:

[0016] Pre-set the first acceleration threshold D a1 Second acceleration threshold D a2 Third acceleration threshold D a3 First velocity threshold D v1 Second velocity threshold D v2 Third velocity threshold D v3 The acceleration step size Δa is set; the first acceleration threshold D after setting is... a1 The second acceleration threshold D a2 and the third acceleration threshold D a3 Both are greater than 0, and D a1 <D a2 <D a3 The first speed threshold D after setting v1 The second speed threshold D v2 and the third velocity threshold D v3 Both are greater than 0, and the first speed threshold D v1 and the second speed threshold D v2 All are much greater than the third velocity threshold D. v3 The acceleration step size Δa after setting is greater than 0.

[0017] Preferably, the step of determining the driving gear position based on the driving gear indicator and the planned acceleration a... plan The planned speed v plan and the real-time vehicle speed v vehicle Confirm whether to enter parking mode, specifically including:

[0018] When the driving gear is marked as D or R, if the planned acceleration a plan The absolute value is less than the first acceleration threshold D a1 And the planned speed v plan The absolute value is less than the first speed threshold D v1 And the real-time vehicle speed v vehicle The absolute value is less than the second speed threshold D v2 If the planned acceleration a is not specified, then the parking mode is confirmed to be entered; otherwise, if the planned acceleration a is not specified, the parking mode is entered. plan The absolute value is greater than or equal to the first acceleration threshold D a1 , or the planned speed v plan The absolute value is greater than or equal to the first speed threshold D v1 , or the real-time vehicle speed v vehicle The absolute value is greater than or equal to the second speed threshold D v2 If so, it confirms that parking mode has not been entered.

[0019] Preferably, the step of determining the driving gear position based on the real-time vehicle speed v... vehicle and the acceleration a of the uphill and downhill slopes offset Target acceleration identification in parking mode generates target acceleration a at time k. target,k Specifically, it includes:

[0020] When the vehicle gear is marked as D, obtain the target acceleration a at the previous moment k-1. target,k-1 ; and based on the real-time vehicle speed v vehicle The acceleration a on the uphill and downhill slopes offset and the target acceleration a target,k-1 The target acceleration a is generated by identifying the target acceleration during the forward movement mode. target,k And save;

[0021] When the vehicle gear position is marked as R, the target acceleration a at the previous moment k-1 is obtained. target,k-1 ; and based on the real-time vehicle speed v vehicle The acceleration a on the uphill and downhill slopes offset and the target acceleration a target,k-1 The target acceleration a is generated by identifying the parking target acceleration in reverse mode. target,k And save it.

[0022] Furthermore, the step of basing the real-time vehicle speed v vehicle The acceleration a on the uphill and downhill slopes offset and the target acceleration a target,k-1 The target acceleration a is generated by identifying the target acceleration during the forward movement mode. target,k And save, specifically including:

[0023] For the real-time vehicle speed v vehicle Is the absolute value less than the third velocity threshold D? v3 Perform identification; if the real-time vehicle speed v vehicle The absolute value is less than the third velocity threshold D v3 Then set the first acceleration parameter a s1 The third acceleration threshold D a3 negative numbers, a s1 =-D a3 Conversely, if the real-time vehicle speed v vehicle The absolute value is greater than or equal to the third velocity threshold D. v3 Then set the first acceleration parameter a s1 The second acceleration threshold D a2 negative numbers, a s1 =-D a2 ;

[0024] According to the aforementioned uphill and downhill acceleration a offset The absolute value of the first acceleration parameter a s1 Acceleration compensation is performed to generate the corresponding second acceleration parameter a. s2 ,a s2 =a s1 -|a offset |;

[0025] Based on the acceleration step size Δa and the target acceleration a at the previous time k-1. target,k-1 Estimate the target acceleration at the current time k to generate the corresponding third acceleration parameter a. s3 a s3 =a target,k-1 -Δa;

[0026] From the second acceleration parameter a s2 and the third acceleration parameter a s3 The maximum value is taken as the target acceleration a at the current time k. target,k And save, a target,k =max(a s2 ,a s3 ).

[0027] Furthermore, the step of basing the real-time vehicle speed v vehicle The acceleration a on the uphill and downhill slopes offset and the target acceleration a target,k-1 The target acceleration a is generated by identifying the parking target acceleration in reverse mode. target,k And save, specifically including:

[0028] For the real-time vehicle speed v vehicle Is the absolute value less than the third velocity threshold D? v3 Perform identification; if the real-time vehicle speed v vehicle The absolute value is less than the third velocity threshold D v3 Then set the fourth acceleration parameter a s4 The third acceleration threshold D a3 a s4 =D a3 Conversely, if the real-time vehicle speed v vehicle The absolute value is greater than or equal to the third velocity threshold D. v3 Then set the fourth acceleration parameter a s4 The second acceleration threshold D a2 a s4 =D a2 ;

[0029] According to the aforementioned uphill and downhill acceleration a offsetThe absolute value of the fourth acceleration parameter a s4 Acceleration compensation is performed to generate the corresponding fifth acceleration parameter a. s5 ,a s5 =a s4 +|a offset |;

[0030] Based on the acceleration step size Δa and the target acceleration a at the previous time k-1. target,k-1 Estimate the target acceleration at the current time k to generate the corresponding sixth acceleration parameter a. s6 a s6 =a target,k-1 +Δa;

[0031] From the fifth acceleration parameter a s5 and the sixth acceleration parameter a s6 The minimum value is taken as the target acceleration a at the current time k. target,k And save, a target,k =min(a s5 ,a s6 ).

[0032] Preferably, the step of controlling acceleration a control and the acceleration a of the uphill and downhill slopes offset Target acceleration identification in non-stop mode generates target acceleration a at time k. target,k Specifically, it includes:

[0033] According to the control acceleration a control and the acceleration a of the uphill and downhill slopes offset The sum is set to the target acceleration a at the current time k. target,k And save, a target,k =a control +a offset .

[0034] A second aspect of the present invention provides an electronic device, including: a memory, a processor, and a transceiver;

[0035] The processor is used to couple with the memory, read and execute instructions in the memory to implement the steps of the method described in the first aspect above;

[0036] The transceiver is coupled to the processor, and the processor controls the transceiver to send and receive messages.

[0037] A third aspect of the present invention provides a computer-readable storage medium storing computer instructions that, when executed by a computer, cause the computer to perform the instructions described in the first aspect.

[0038] This invention provides a method for controlling the percentage of braking force, an electronic device, and a computer-readable storage medium. First, the corresponding uphill and downhill accelerations are calculated based on the pitch angle output by the positioning module. Then, based on the vehicle gear position indicator, the planned speed and planned acceleration output by the planning module, and the real-time vehicle speed output by the positioning module or chassis module, it is determined whether to enter a parking mode. If parking mode is confirmed, it further judges whether the real-time vehicle speed is lower than a preset threshold. If it is not lower than the preset threshold, a braking acceleration parameter with a smaller absolute value is set; if it is lower than the preset threshold, a braking acceleration parameter with a larger absolute value is set. The obtained braking acceleration parameter is then compensated using uphill and downhill accelerations to obtain a supplementary braking force. The system calculates the acceleration parameters and estimates an estimated acceleration parameter based on the target acceleration from the previous moment and a preset acceleration step size. When the vehicle is marked as D gear, the maximum value of the compensated acceleration parameter and the estimated acceleration parameter is taken as the target acceleration output. When the vehicle is marked as R gear, the minimum value of the compensated acceleration parameter and the estimated acceleration parameter is taken as the target acceleration output. If it is confirmed that the vehicle has not entered parking mode, the system uses uphill and downhill acceleration to compensate for the control acceleration output by the control module and takes the compensation result as the target acceleration output. After obtaining the target acceleration output, the autonomous driving system looks up the corresponding braking percentage based on the real-time vehicle speed and the target acceleration. This invention allows for the braking process to be divided into two stages: high-speed gentle braking and low-speed heavy braking, based on whether the real-time vehicle speed is below a preset threshold. This solves the problem of excessive braking that is common in conventional technical solutions, improves passenger comfort, and prevents vehicles with idling speed from rolling back or braking too suddenly when starting. Furthermore, by using acceleration compensation for uphill and downhill acceleration, the invention addresses the problem of rolling back on slopes that is common in conventional technical solutions, thus improving vehicle driving safety. Attached Figure Description

[0039] Figure 1 This is a schematic diagram of a method for controlling the braking percentage provided in Embodiment 1 of the present invention;

[0040] Figure 2 This is a schematic diagram of positive and negative pitch angles provided in Embodiment 1 of the present invention;

[0041] Figure 3 This is a schematic diagram of the structure of an electronic device provided in Embodiment 2 of the present invention. Detailed Implementation

[0042] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0043] Embodiment 1 of the present invention provides a method for controlling the braking percentage, such as... Figure 1 The schematic diagram shows a method for controlling the braking percentage provided in Embodiment 1 of the present invention. This method mainly includes the following steps:

[0044] Step 1, obtain the planned velocity v at time k. plan Planning acceleration a plan Controlling acceleration a control Pitch angle θ, real-time vehicle speed v vehicle and driving gear position markings;

[0045] The driving gear markings include the D gear marking and the R gear marking.

[0046] Here, the control acceleration a at time k of the longitudinal controller output of the autonomous driving system is... control At that time, the control acceleration a at time k is obtained from the planning module. control The corresponding planned speed v plan and planning acceleration a plan And obtain the control acceleration a at time k from the positioning module. control The corresponding pitch angle θ is obtained from the positioning module or chassis module, and the control acceleration a at time k is obtained. control The corresponding real-time vehicle speed v vehicle The system then obtains the vehicle's current gear position indication; this indication should include at least the driving gear (D) and reverse gear (R) indications. If the vehicle is in motion, the real-time vehicle speed v is also considered. vehicle The vehicle speed is generated by the vehicle's autonomous driving system through throttle and brake control; if the vehicle has a start-up idle function and is in a starting state and the vehicle's autonomous driving system has not yet performed any operation on the throttle or brake, then the real-time vehicle speed v is... vehicle This refers to the vehicle speed generated by the vehicle's idling acceleration. In addition, some vehicles will subdivide the driving gear markings into D1, D2...Dn gears, and some vehicles will also provide a sport gear, or S gear. In this case, all the subdivided driving gear markings (D1, D2...Dn gears, S gear) can be regarded as D gear markings.

[0047] It should be noted that the method in this embodiment of the invention obtains the planned velocity v at time k. planPlanning acceleration a plan Controlling acceleration a control Pitch angle θ, real-time vehicle speed v vehicle Before the driving gear indicator, it also includes: pre-setting the first acceleration threshold D a1 Second acceleration threshold D a2 Third acceleration threshold D a3 First velocity threshold D v1 Second velocity threshold D v2 Third velocity threshold D v3 Set the acceleration step size Δa; the first acceleration threshold D after setting. a1 Second acceleration threshold D a2 and the third acceleration threshold D a3 Both are greater than 0, and D a1 <D a2 <D a3 The first speed threshold D after setting v1 Second velocity threshold D v2 and the third velocity threshold D v3 All are greater than 0, and the first velocity threshold D v1 Second velocity threshold D v2 All are much greater than the third velocity threshold D v3 The set acceleration step size Δa is greater than 0.

[0048] Here, in this embodiment of the invention, a set of empirical thresholds is preset before step 1: the first acceleration threshold D a1 Second acceleration threshold D a2 Third acceleration threshold D a3 First velocity threshold D v1 Second velocity threshold D v2 Third velocity threshold D v3 And the acceleration step size Δa, for use in subsequent steps. Wherein, the first acceleration threshold D... a1 Second acceleration threshold D a2 The default value is a small acceleration, such as D. a1 0.1 m / s 2 D a2 0.4 m / s 2 The third acceleration threshold D a3 Compared to the first and second acceleration thresholds, this would be a large acceleration, for example, D. a3 1.5m / s 2 First velocity threshold D v1 Second velocity threshold D v2 The default value is a small velocity value, and the two values ​​can be equal, for example, D. v1 0.5m / s, Dv2 The third velocity threshold D is 0.5 m / s. v3 Compared to the first and second speed thresholds, it is a small speed value that is much smaller than both and close to 0, for example, D. v3 The acceleration step size is 0.01 m / s; the acceleration step size Δa is a preset empirical step size value, which should be greater than 0.

[0049] Step 2: Based on the pitch angle θ, identify the uphill and downhill accelerations and generate the corresponding uphill and downhill accelerations a. offset ;

[0050] Specifically, this includes: calculating and generating the corresponding uphill and downhill accelerations a based on the pitch angle θ and gravitational acceleration g. offset a offset = -sinθ*g;

[0051] Where the pitch angle θ is greater than 0, it is the downhill pitch angle, and the corresponding uphill and downhill acceleration a offset For downhill acceleration, a offset <0; When the pitch angle θ is less than 0, it is the uphill pitch angle, and the corresponding uphill and downhill acceleration a offset For uphill acceleration, a offset >0.

[0052] Here, based on the principle of pitch angle θ, if a right-handed coordinate system is constructed with the right side of the vehicle body as the positive X-axis and the front of the vehicle as the positive Y-axis, then the pitch angle θ is the rotation angle of the vehicle along the X-axis. The pitch angle θ is positive if it is below the horizontal plane and negative if it is above the horizontal plane. As is known from basic physics, when an object is on a slope, it will generate a gravitational acceleration component along the slope direction, influenced by gravity. In this embodiment of the invention, the uphill / downhill acceleration 'a'... offset In reality, it is the reverse cancellation of the gravitational acceleration component caused by the pitch angle of the vehicle's position; when the vehicle is on a slope, the pitch angle θ can be regarded as the angle between the slope and the horizontal plane.

[0053] by Figure 2 Taking the schematic diagram of positive and negative pitch angles provided in Embodiment 1 of the present invention as an example, when the front of the vehicle is downward, the pitch angle θ is positive and θ>0, and the driving direction is downward. Then, the direction of the corresponding gravitational acceleration component is downward along the slope, and the acceleration a on the slope is downward. offset The direction is upward along the slope and the value is negative; when the front of the car is upward, the pitch angle θ is negative and θ<0, and the direction of travel is upward. Therefore, the direction of the corresponding gravitational acceleration component is downward along the slope, and the acceleration a is the acceleration when going uphill or downhill. offset The direction is upward along the slope, and the value is positive.

[0054] Step 3, based on the vehicle gear position markings and the planned acceleration a plan Planning speed v plan and real-time vehicle speed v vehicleConfirm whether parking mode has been entered; if parking mode has been entered, proceed to step 4; if parking mode has not been entered, proceed to step 5.

[0055] Step 31, based on the vehicle gear position markings and the planned acceleration a plan Planning speed v plan and real-time vehicle speed v vehicle Confirm whether to enter parking mode;

[0056] Specifically, this includes: when the driving gear is marked as D or R, if the planned acceleration a plan The absolute value is less than the first acceleration threshold D a1 And the planned speed v plan The absolute value is less than the first velocity threshold D v1 And the real-time vehicle speed v vehicle The absolute value is less than the second velocity threshold D v2 If the acceleration a is not specified, then the parking mode is confirmed; otherwise, if the planned acceleration a is not specified, the parking mode is confirmed. plan The absolute value is greater than or equal to the first acceleration threshold D a1 Or the planned speed v plan The absolute value is greater than or equal to the first velocity threshold D v1 or real-time vehicle speed v vehicle The absolute value is greater than or equal to the second velocity threshold D v2 If so, it confirms that parking mode has not been entered;

[0057] Here, when the driving gear is marked as D or R, if |a plan | <D a1 And |v plan | <D v1 And |v vehicle | <D v2 This indicates that the planned speed, real-time speed, and planned acceleration of the current vehicle are all very small. In this case, the embodiment of the present invention will default to entering parking mode; conversely, if |a plan |≥D a1 or |v plan |≥D v1 or |v vehicle |≥D v2 They will not enter parking mode;

[0058] Step 32: If it is confirmed that the parking mode has been entered, proceed to step 4; if it is confirmed that the parking mode has not been entered, proceed to step 5.

[0059] Step 4, based on the vehicle gear position indicator and real-time vehicle speed v vehicle and acceleration a on slope offset Target acceleration identification in parking mode generates target acceleration a at time k. target,kProceed to step 6;

[0060] Specifically, this includes: Step 41, when the vehicle gear position is marked as D, obtaining the target acceleration a at the previous moment k-1. target,k-1 And based on the real-time vehicle speed v vehicle Acceleration a on slopes offset and target acceleration a target,k-1 The target acceleration a is generated by identifying the target acceleration during the parking process in forward mode. target,k Save the file; proceed to step 6.

[0061] Specifically, this includes: Step 411, when the vehicle gear position is marked as D, obtaining the target acceleration a at the previous moment k-1. target,k-1 ;

[0062] Step 412, based on the real-time vehicle speed v vehicle Acceleration a on slopes offset and target acceleration a target,k -1 Performs target acceleration recognition in forward mode to generate corresponding target acceleration a. target,k And save;

[0063] Specifically, this includes: Step 4121, setting the real-time vehicle speed v vehicle Is the absolute value less than the third velocity threshold D? v3 Perform identification; if the real-time vehicle speed v vehicle The absolute value is less than the third velocity threshold D v3 Then set the first acceleration parameter a s1 The third acceleration threshold D a3 negative numbers, a s1 =-D a3 Conversely, if the real-time vehicle speed v vehicle The absolute value is greater than or equal to the third velocity threshold D v3 Then set the first acceleration parameter a s1 The second acceleration threshold D a2 negative numbers, a s1 =-D a2 ;

[0064] Here, the real-time vehicle speed v vehicle This represents a positive forward driving speed; as mentioned earlier, the third speed threshold D... v3 It is a small speed value close to 0; the embodiment of the present invention uses a third speed threshold D. v3 This serves as a dividing line between high-speed gentle braking and low-speed heavy braking; if the real-time vehicle speed v vehicle The absolute value is greater than or equal to the third velocity threshold D v3This indicates that the vehicle is currently in a high-speed, gradual braking phase. In this case, the embodiment of the present invention will set a braking acceleration parameter with a relatively small absolute value, namely the first acceleration parameter a. s1 =-D a2 If the real-time vehicle speed v vehicle The absolute value is less than the third velocity threshold D v3 This indicates that the vehicle is currently in a low-speed, heavy braking phase. In this case, the embodiment of the present invention will set a braking acceleration parameter with a relatively large absolute value, namely the first acceleration parameter a. s1 =-D a3 The first acceleration parameter a obtained s1 It is a negative number;

[0065] Step 4122, based on the acceleration a of the uphill and downhill slopes offset The absolute value of the first acceleration parameter a s1 Acceleration compensation is performed to generate the corresponding second acceleration parameter a. s2 ,

[0066] a s2 =a s1 -|a offset |;

[0067] Here, the second acceleration parameter a is obtained. s2 It is a negative number;

[0068] In principle, it is based on the acceleration a of going uphill and downhill. offset The compensation method should be: a s2 =a s1 +a offset However, in practical applications, it has been found that while this method can indeed enhance the compensation acceleration parameter, i.e., the second acceleration parameter a, when parking on a downhill slope, it is not ideal. s2 It is more conducive to controlling the vehicle's rollback on downhill slopes and can effectively shorten the braking process of high-speed slow braking, but it will weaken the compensating acceleration parameter, i.e., the second acceleration parameter a, when stopping on an uphill slope. s2 This could result in insufficient braking force when going uphill, causing the vehicle to roll back uphill, and prolonging the braking process of high-speed slow braking.

[0069] To solve this problem, embodiments of the present invention use uphill / downhill acceleration a offset The absolute value of the braking acceleration parameter obtained is the first acceleration parameter a. s1 The compensation acceleration parameter, i.e., the second acceleration parameter a, is obtained by performing compensation. s2 The acceleration compensation method of this embodiment of the invention, when stopping on a downhill slope, is similar to a s2 =a s1 +a offset The equivalent is still based on the acceleration a of going uphill and downhill. offset For the first acceleration parameter a s1Enhanced compensation was implemented, and the acceleration a during uphill parking is also based on the uphill and downhill acceleration. offset For the first acceleration parameter a s1 Enhanced compensation has been implemented to ensure that the vehicle can prevent rolling back uphill when parking on an incline and to effectively shorten the braking process of high-speed slow braking.

[0070] Step 4123, based on the acceleration step size Δa and the target acceleration a at the previous moment k-1. target,k-1 Estimate the target acceleration at the current time k to generate the corresponding third acceleration parameter a. s3 ,

[0071] a s3 =a target,k-1 -Δa;

[0072] Here, the larger the preset acceleration step size Δa, the greater the increase in braking deceleration, and the faster the braking; the smaller the preset acceleration step size Δa, the greater the increase in braking deceleration, and the slower the braking; the resulting third acceleration parameter a s3 It is a negative number;

[0073] Step 4124, from the second acceleration parameter a s2 and the third acceleration parameter a s3 The maximum value is taken as the target acceleration a at the current time k. target,k And save it.

[0074] a target,k =max(a s2 ,a s3 );

[0075] Here, the second acceleration parameter a s2 and the third acceleration parameter a s3 All are negative numbers, the selected target acceleration a target,k In reality, it is the acceleration with the smaller absolute value of the two. This is done to prevent excessive deceleration in a single step from causing too sudden braking. After step 4124, we will proceed to step 6.

[0076] Step 42: When the gear position is marked as R, obtain the target acceleration a at the previous moment k-1. target,k-1 And based on the real-time vehicle speed v vehicle Acceleration a on slopes offset and target acceleration a target,k-1 Reverse parking target acceleration recognition to generate corresponding target acceleration 'a' target,k And save;

[0077] Specifically, this includes: Step 421, when the vehicle gear position is marked as R, obtaining the target acceleration a at the previous moment k-1. target,k-1 ;

[0078] Step 422, based on the real-time vehicle speed v vehicle Acceleration a on slopes offset and target acceleration a target,k-1 Reverse parking target acceleration recognition to generate corresponding target acceleration 'a' target,k And save;

[0079] Specifically, this includes: step 4221, setting the real-time vehicle speed v vehicle Is the absolute value less than the third velocity threshold D? v3 Perform identification; if the real-time vehicle speed v vehicle The absolute value is less than the third velocity threshold D v3 Then set the fourth acceleration parameter a s4 The third acceleration threshold D a3 a s4 =D a3 Conversely, if the real-time vehicle speed v vehicle The absolute value is greater than or equal to the third velocity threshold D v3 Then set the fourth acceleration parameter a s4 The second acceleration threshold D a2 a s4 =D a2 ;

[0080] Here, the real-time vehicle speed v vehicle This represents a negative reverse speed; as mentioned earlier, the third speed threshold D... v3 It is a small speed value close to 0; the embodiment of the present invention uses a third speed threshold D. v3 This serves as a dividing line between high-speed gentle braking and low-speed heavy braking; if the real-time vehicle speed v vehicle The absolute value is greater than or equal to the third velocity threshold D v3 This indicates that the vehicle is currently in a high-speed, gradual braking phase. In this case, the embodiment of the present invention will set a braking acceleration parameter with a relatively small absolute value, namely the fourth acceleration parameter a. s4 =D a2 If the real-time vehicle speed v vehicle The absolute value is less than the third velocity threshold D v3 This indicates that the vehicle is currently in a low-speed, heavy braking phase. In this case, the embodiment of the present invention will set a braking acceleration parameter with a relatively large absolute value, namely the fourth acceleration parameter a. s4 =D a3 The fourth acceleration parameter a was obtained. s4 It is a positive number;

[0081] Step 4222, based on the acceleration a of the uphill and downhill slopes offset The absolute value of the fourth acceleration parameter a s4 Acceleration compensation is performed to generate the corresponding fifth acceleration parameter a.s5 ,

[0082] a s5 =a s4 +|a offset |;

[0083] Here, the embodiments of the present invention will use the uphill and downhill acceleration a. offset The absolute value of the braking acceleration parameter obtained is the fourth acceleration parameter a. s4 The compensation acceleration parameter, i.e., the fifth acceleration parameter a, is obtained by performing compensation. s5 The fifth acceleration parameter a was obtained. s5 It is a positive number; the reason for using the acceleration a of going uphill or downhill is to use the acceleration a of going uphill or offset The absolute value is compensated because when the driving gear is marked as R, the fourth acceleration parameter a s4 If the value is negative, use the acceleration a for uphill and downhill slopes. offset The absolute value through a s4 +|a offset | method for the fourth acceleration parameter a s4 Compensation can make the obtained compensated acceleration parameter, i.e., the fifth acceleration parameter a, more accurate. s5 The increase in absolute value and the strengthening of braking force make it easier to control the vehicle from rolling backward;

[0084] Step 4223, based on the acceleration step size Δa and the target acceleration a at the previous moment k-1. target,k-1 Estimate the target acceleration at the current time k to generate the corresponding sixth acceleration parameter a. s6 ,

[0085] a s6 =a target,k-1 +Δa;

[0086] Here, the larger the preset acceleration step size Δa, the greater the increase in braking deceleration, and the faster the braking; the smaller the preset acceleration step size Δa, the greater the increase in braking deceleration, and the slower the braking; the resulting sixth acceleration parameter a s6 It is a positive number;

[0087] Step 4224, from the fifth acceleration parameter a s5 and the sixth acceleration parameter a s6 The minimum value is taken as the target acceleration a at the current time k. target,k And save it.

[0088] a target,k =min(a s5 ,a s6 ).

[0089] Here, the fifth acceleration parameter a s5 and the sixth acceleration parameter as6 All are positive numbers, the selected target acceleration a target,k In reality, it is the acceleration with the smaller absolute value of the two. The reason for doing this is to prevent excessive deceleration in a single step from causing the problem of excessive braking. After step 4224, we will proceed to step 6.

[0090] Step 5, based on the control acceleration a control and acceleration a on slope offset Target acceleration identification in non-stop mode generates target acceleration a at time k. target,k ;

[0091] Specifically, this includes: based on the control acceleration a control and acceleration a on slope offset The sum is set to the target acceleration a at the current time k. target,k And save it.

[0092] a target,k =a control +a offset .

[0093] Here, in this embodiment of the invention, when it is confirmed that the parking mode has not been entered, the uphill / downhill acceleration 'a' will be used. offset The control acceleration a output by the control module control Perform compensation and use the compensation result as the target acceleration a at the current time k. target,k Output.

[0094] Step 6: Query the preset first correspondence table reflecting the relationship between real-time vehicle speed, target acceleration, and braking percentage, and match the first vehicle speed range field in the first correspondence table with the real-time vehicle speed v. vehicle The first acceleration range field matches the target acceleration a. target,k The first braking percentage field of the first matching record is extracted as the braking percentage at the current time k;

[0095] The first correspondence table includes multiple first correspondence records; each first correspondence record includes a first vehicle speed range field, a first acceleration range field, and a first braking percentage field.

[0096] Here, we obtain the target acceleration a at the current time k. target,k Then, based on the real-time vehicle speed v vehicle +Target acceleration a target,k The corresponding braking percentage is obtained by looking up a table. After obtaining the braking percentage at the current time k, the autonomous driving system will control the opening and closing of the vehicle's brake pedal based on this braking percentage.

[0097] Figure 3This is a schematic diagram of an electronic device provided in Embodiment 2 of the present invention. This electronic device can be the aforementioned terminal device or server, or it can be a terminal device or server connected to the aforementioned terminal device or server that implements the method of the embodiments of the present invention. Figure 3 As shown, the electronic device may include: a processor 301 (e.g., CPU), a memory 302, and a transceiver 303; the transceiver 303 is coupled to the processor 301, and the processor 301 controls the transmission and reception operations of the transceiver 303. The memory 302 may store various instructions for performing various processing functions and implementing the processing steps described in the foregoing method embodiments. Preferably, the electronic device involved in the embodiments of the present invention further includes: a power supply 304, a system bus 305, and a communication port 306. The system bus 305 is used to realize communication connections between components. The communication port 306 is used for communication between the electronic device and other peripherals.

[0098] exist Figure 3 The system bus 305 mentioned can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This system bus can be divided into address bus, data bus, control bus, etc. For ease of representation, Figure 3 The symbol is represented by a single thick line, but this does not imply that there is only one bus or one type of bus. The communication interface is used to enable communication between the database access device and other devices (e.g., clients, read-write libraries, and read-only libraries). Memory may include random access memory (RAM) and may also include non-volatile memory, such as at least one disk drive.

[0099] The processors mentioned above can be general-purpose processors, including central processing units (CPUs), network processors (NPs), graphics processing units (GPUs), etc.; they can also be digital signal processors (DSPs), application-specific integrated circuits (ASICs), field-programmable gate arrays (FPGAs), or other programmable logic devices, discrete gate or transistor logic devices, or discrete hardware components.

[0100] It should be noted that the embodiments of the present invention also provide a computer-readable storage medium storing instructions that, when run on a computer, cause the computer to perform the methods and processes provided in the above embodiments.

[0101] This invention also provides a chip for executing instructions, which is used to perform the processing steps described in the foregoing method embodiments.

[0102] This invention provides a method for controlling the percentage of braking force, an electronic device, and a computer-readable storage medium. First, the corresponding uphill and downhill accelerations are calculated based on the pitch angle output by the positioning module. Then, based on the vehicle gear position indicator, the planned speed and planned acceleration output by the planning module, and the real-time vehicle speed output by the positioning module or chassis module, it is determined whether to enter a parking mode. If parking mode is confirmed, it further judges whether the real-time vehicle speed is lower than a preset threshold. If it is not lower than the preset threshold, a braking acceleration parameter with a smaller absolute value is set; if it is lower than the preset threshold, a braking acceleration parameter with a larger absolute value is set. The obtained braking acceleration parameter is then compensated using uphill and downhill accelerations to obtain a supplementary braking force. The system calculates the acceleration parameters and estimates an estimated acceleration parameter based on the target acceleration from the previous moment and a preset acceleration step size. When the vehicle is marked as D gear, the maximum value of the compensated acceleration parameter and the estimated acceleration parameter is taken as the target acceleration output. When the vehicle is marked as R gear, the minimum value of the compensated acceleration parameter and the estimated acceleration parameter is taken as the target acceleration output. If it is confirmed that the vehicle has not entered parking mode, the system uses uphill and downhill acceleration to compensate for the control acceleration output by the control module and takes the compensation result as the target acceleration output. After obtaining the target acceleration output, the autonomous driving system looks up the corresponding braking percentage based on the real-time vehicle speed and the target acceleration. This invention allows for the braking process to be divided into two stages: high-speed gentle braking and low-speed heavy braking, based on whether the real-time vehicle speed is below a preset threshold. This solves the problem of excessive braking that is common in conventional technical solutions, improves passenger comfort, and prevents vehicles with idling speed from rolling back or braking too suddenly when starting. Furthermore, by using acceleration compensation for uphill and downhill acceleration, the invention addresses the problem of rolling back on slopes that is common in conventional technical solutions, thus improving vehicle driving safety.

[0103] Those skilled in the art will further recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, computer software, or a combination of both. To clearly illustrate the interchangeability of hardware and software, the components and steps of the various examples have been generally described in terms of functionality in the foregoing description. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementations should not be considered beyond the scope of this invention.

[0104] The steps of the methods or algorithms described in conjunction with the embodiments disclosed herein can be implemented in hardware, a software module executed by a processor, or a combination of both. The software module can be located in random access memory (RAM), main memory, read-only memory (ROM), electrically programmable ROM, electrically erasable programmable ROM, registers, hard disk, removable disk, CD-ROM, or any other form of storage medium known in the art.

[0105] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for controlling the percentage of braking force, characterized in that, The method includes: a planning speed v at the acquisition time point k plan , a planning acceleration a plan , a control acceleration a control , a pitch angle θ, a real-time vehicle speed v vehicle , and a driving range mark; the driving range mark includes a D range mark and an R range mark; According to the pitch angle θ, the uphill and downhill acceleration recognition is generated to correspond to the uphill and downhill acceleration a offset ; Based on the vehicle gear position indicator and the planned acceleration a plan The planned speed v plan and the real-time vehicle speed v vehicle Confirm whether to enter parking mode; If it is confirmed that parking mode has been entered, then based on the driving gear indicator and the real-time vehicle speed v vehicle and the acceleration a of the uphill and downhill slopes offset Target acceleration identification in parking mode generates target acceleration a at time k. target,k ; If it is confirmed that the parking mode has not been entered, then according to the control acceleration a... control and the acceleration a of the uphill and downhill slopes offset Target acceleration identification in non-stop mode generates target acceleration a at time k. target,k ; Query a preset first correspondence table reflecting the relationship between real-time vehicle speed, target acceleration, and braking percentage, and match the first vehicle speed range field in the first correspondence table with the real-time vehicle speed v. vehicle The first acceleration range field matches the target acceleration a. target,k The first braking percentage field of the first matching record is extracted as the braking percentage at the current time k; the first matching table includes multiple first matching records; the first matching record includes the first vehicle speed range field, the first acceleration range field, and the first braking percentage field.

2. The method for controlling the braking percentage according to claim 1, characterized in that, The uphill and downhill accelerations are identified and corresponding uphill and downhill accelerations a are generated based on the pitch angle θ. offset Specifically, it includes: The corresponding uphill / downhill acceleration a is calculated based on the pitch angle θ and gravitational acceleration g. offset a offset = -sinθ*g; When the pitch angle θ is greater than 0, it is the downhill pitch angle, and the corresponding uphill and downhill acceleration a offset For downhill acceleration, a offset <0; When the pitch angle θ is less than 0, it is the uphill pitch angle, and the corresponding uphill / downhill acceleration a offset For uphill acceleration, a offset >0.

3. The method for controlling the braking percentage according to claim 1, characterized in that, The planned velocity v at time k is obtained plan Planning acceleration a plan Controlling acceleration a control Pitch angle θ, real-time vehicle speed v vehicle Before the gear position indicator, the method further includes: Pre-set the first acceleration threshold D a1 Second acceleration threshold D a2 Third acceleration threshold D a3 First velocity threshold D v1 Second velocity threshold D v2 Third velocity threshold D v3 The acceleration step size Δa is set; the first acceleration threshold D after setting is... a1 The second acceleration threshold D a2 and the third acceleration threshold D a3 Both are greater than 0, and D a1 <D a2 <D a3 The first speed threshold D after setting v1 The second speed threshold D v2 and the third velocity threshold D v3 Both are greater than 0, and the first speed threshold D v1 and the second speed threshold D v2 All are much greater than the third velocity threshold D. v3 The acceleration step size Δa after setting is greater than 0.

4. The method for controlling the braking percentage according to claim 3, characterized in that, The method is based on the vehicle gear position mark and the planned acceleration a. plan The planned speed v plan and the real-time vehicle speed v vehicle Confirm whether to enter parking mode, specifically including: When the driving gear is marked as D or R, if the planned acceleration a plan The absolute value is less than the first acceleration threshold D a1 And the planned speed v plan The absolute value is less than the first speed threshold D v1 And the real-time vehicle speed v vehicle The absolute value is less than the second speed threshold D v2 If the planned acceleration a is not specified, then the parking mode is confirmed to be entered; otherwise, if the planned acceleration a is not specified, the parking mode is entered. plan The absolute value is greater than or equal to the first acceleration threshold D a1 , or the planned speed v plan The absolute value is greater than or equal to the first speed threshold D v1 , or the real-time vehicle speed v vehicle The absolute value is greater than or equal to the second speed threshold D v2 If so, it confirms that parking mode has not been entered.

5. The method for controlling the braking percentage according to claim 3, characterized in that, The information is based on the vehicle gear position indicator and the real-time vehicle speed v. vehicle and the acceleration a of the uphill and downhill slopes offset Target acceleration identification in parking mode generates target acceleration a at time k. target,k Specifically, it includes: When the vehicle gear is marked as D, obtain the target acceleration a at the previous moment k-1. target,k-1 ; and based on the real-time vehicle speed v vehicle The acceleration a on the uphill and downhill slopes offset and the target acceleration a target,k-1 The target acceleration a is generated by identifying the target acceleration during the forward movement mode. target,k And save; When the vehicle gear position is marked as R, the target acceleration a at the previous moment k-1 is obtained. target,k-1 ; and based on the real-time vehicle speed v vehicle The acceleration a on the uphill and downhill slopes offset and the target acceleration a target,k-1 The target acceleration a is generated by identifying the parking target acceleration in reverse mode. target,k And save it.

6. The method for controlling the braking percentage according to claim 5, characterized in that, According to the real-time vehicle speed v vehicle The acceleration a on the uphill and downhill slopes offset and the target acceleration a target,k-1 The target acceleration a is generated by identifying the target acceleration during the forward movement mode. target,k And save, specifically including: For the real-time vehicle speed v vehicle Is the absolute value less than the third velocity threshold D? v3 Perform identification; if the real-time vehicle speed v vehicle The absolute value is less than the third velocity threshold D v3 Then set the first acceleration parameter a s1 The third acceleration threshold D a3 negative numbers, a s1 =-D a3 Conversely, if the real-time vehicle speed v vehicle The absolute value is greater than or equal to the third velocity threshold D. v3 Then set the first acceleration parameter a s1 The second acceleration threshold D a2 negative numbers, a s1 =-D a2 ; According to the aforementioned uphill and downhill acceleration a offset The absolute value of the first acceleration parameter a s1 Acceleration compensation is performed to generate the corresponding second acceleration parameter a. s2 ,a s2 =a s1 -|a offset |; Based on the acceleration step size Δa and the target acceleration a at the previous time k-1. target,k-1 Estimate the target acceleration at the current time k to generate the corresponding third acceleration parameter a. s3 a s3 =a target,k-1 -Δa; From the second acceleration parameter a s2 and the third acceleration parameter a s3 The maximum value is taken as the target acceleration a at the current time k. target,k And save, a target,k =max(a s2 ,a s3 ).

7. The method for controlling the braking percentage according to claim 5, characterized in that, According to the real-time vehicle speed v vehicle The acceleration a on the uphill and downhill slopes offset and the target acceleration a target,k-1 The target acceleration a is generated by identifying the parking target acceleration in reverse mode. target,k And save, specifically including: For the real-time vehicle speed v vehicle Is the absolute value less than the third velocity threshold D? v3 Perform identification; if the real-time vehicle speed v vehicle The absolute value is less than the third velocity threshold D v3 Then set the fourth acceleration parameter a s4 The third acceleration threshold D a3 a s4 =D a3 Conversely, if the real-time vehicle speed v vehicle The absolute value is greater than or equal to the third velocity threshold D. v3 Then set the fourth acceleration parameter a s4 The second acceleration threshold D a2 a s4 =D a2 ; According to the aforementioned uphill and downhill acceleration a offset The absolute value of the fourth acceleration parameter a s4 Acceleration compensation is performed to generate the corresponding fifth acceleration parameter a. s5 ,a s5 =a s4 +|a offset |; Based on the acceleration step size Δa and the target acceleration a at the previous time k-1. target,k-1 Estimate the target acceleration at the current time k to generate the corresponding sixth acceleration parameter a. s6 a s6 =a target,k-1 +Δa; From the fifth acceleration parameter a s5 and the sixth acceleration parameter a s6 The minimum value is taken as the target acceleration a at the current time k. target,k And save, a target,k =min(a s5 ,a s6 ).

8. The method for controlling the braking percentage according to claim 1, characterized in that, The control acceleration a control and the acceleration a of the uphill and downhill slopes offset Target acceleration identification in non-stop mode generates target acceleration a at time k. target,k Specifically, it includes: According to the control acceleration a control and the acceleration a of the uphill and downhill slopes offset The sum is set to the target acceleration a at the current time k. target,k And save, a target,k =a control +a offset .

9. An electronic device, characterized in that, include: Memory, processor, and transceiver; The processor is configured to be coupled to the memory, read and execute instructions in the memory to implement the steps of the method according to any one of claims 1-8; The transceiver is coupled to the processor, and the processor controls the transceiver to send and receive messages.

10. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores computer instructions that, when executed by a computer, cause the computer to perform the instructions of any one of claims 1-8.

Images