Downhill section deceleration determination method, controller, device and medium

Abstract

This application provides a method, controller, device, and medium for determining deceleration on downhill sections, relating to the field of vehicle control technology. It includes: acquiring vehicle operating state parameters, including planned deceleration, vehicle speed, and gradient angle; calculating a deceleration safety margin based on the difference between a preset upper limit of deceleration and the planned deceleration; determining a deceleration correction value based on vehicle speed, gradient angle, planned deceleration, and deceleration safety margin; and determining a target deceleration based on the deceleration correction value and the planned deceleration. The method of this application improves the smoothness, ride comfort, and braking safety of longitudinal control of the vehicle along the road direction, and is beneficial for enhancing the vehicle's adaptability to different downhill scenarios such as urban roads, highways, park roads, and underground parking garage ramps.

Description

Technical Field

[0001] This application relates to the field of vehicle control technology, and in particular to a method, controller, device and medium for determining deceleration on a downhill section. Background Technology

[0002] With the popularization of intelligent driving technology, longitudinal control of vehicles in complex road conditions has become the core of ensuring driving safety. On downhill sections, due to the effect of gravity, vehicles are prone to actual deceleration exceeding expectations or insufficient braking performance, directly affecting driving safety and passenger comfort.

[0003] In existing technologies, vehicles typically employ hill descent control or cruise control strategies on long downhill or steep slopes. A common method involves monitoring vehicle speed using wheel speed sensors. When the speed exceeds a preset threshold, the electronic stability program or braking system directly intervenes, applying a fixed braking force. Alternatively, an inertial measurement unit can be used to directly read the vehicle's pitch angle as slope information, linearly increasing braking pressure according to the slope to counteract the acceleration effect of gravity and maintain the driver's target speed.

[0004] However, existing technology can easily cause the actual deceleration to exceed the safety limit, leading to vehicle jerking or braking instability. Summary of the Invention

[0005] This application provides a method, controller, device, and medium for determining deceleration on downhill sections to solve the aforementioned technical problems. This solution addresses longitudinal deceleration control during vehicle downhill driving, comprehensively considering the correlation between vehicle operating parameters, and coordinating safety and adaptability in the planned deceleration. This results in a more reasonable target deceleration under different slopes and vehicle speeds, improving the stability and coordination of deceleration output in downhill scenarios.

[0006] In a first aspect, this application provides a method for determining deceleration on a downhill section, the method comprising:

[0007] Obtain the vehicle's operating status parameters, including: planned deceleration, vehicle speed, and slope angle;

[0008] Calculate the deceleration safety margin based on the difference between the preset deceleration upper limit and the planned deceleration;

[0009] The deceleration correction value is determined based on the vehicle speed, slope angle, planned deceleration, and deceleration safety margin.

[0010] The target deceleration is determined based on the deceleration correction value and the planned deceleration.

[0011] In one possible implementation, determining the deceleration correction value includes:

[0012] Calculate the adaptive threshold value based on vehicle speed and slope angle;

[0013] The deceleration correction value is determined based on vehicle speed, slope angle, adaptive threshold, planned deceleration, and deceleration safety margin.

[0014] In one possible implementation, determining the deceleration correction value includes:

[0015] Calculate the slope compensation deceleration based on the slope angle and gravitational acceleration;

[0016] The deceleration correction value is determined based on vehicle speed, slope compensation deceleration, adaptive threshold, planned deceleration, and deceleration safety margin.

[0017] In one possible implementation, determining the deceleration correction value includes:

[0018] When the preset conditions are met, the deceleration correction value is determined to be zero;

[0019] The preset conditions are: the vehicle speed is greater than the preset vehicle speed, and the absolute value of the slope compensation deceleration is greater than the first product of the absolute value of the planned deceleration and the adaptive threshold value.

[0020] In one possible implementation, it also includes:

[0021] When the preset conditions are not met, the slope correction coefficient is determined based on the slope compensation deceleration and the planned deceleration. The second product of the slope correction coefficient and the slope compensation deceleration is calculated, and the minimum value between the second product and the deceleration safety margin is taken as the deceleration correction value.

[0022] In one possible implementation, determining the ramp correction factor includes:

[0023] Add the absolute value of the planned deceleration to the absolute value of the slope compensation deceleration to obtain the first summation term;

[0024] The ratio of the absolute value of the ramp compensation deceleration to the first summation term is determined as the ramp correction factor.

[0025] In one possible implementation, calculating the ramp compensation deceleration includes:

[0026] Calculate the sine value of the slope angle;

[0027] The third product of gravitational acceleration and the sine value is used as the ramp compensation deceleration.

[0028] In one possible implementation, calculating the adaptive threshold value includes:

[0029] Calculate the fourth product of the vehicle speed and the preset vehicle speed coefficient;

[0030] Calculate the fifth product of the absolute value of the slope angle and the preset slope coefficient;

[0031] The adaptive threshold value is determined based on the fourth product, the fifth product, and the preset basic scaling factor.

[0032] In one possible implementation, determining the adaptive threshold value includes:

[0033] Add the preset constant 1, the fourth product, and the fifth product together to obtain the second summation term;

[0034] Multiply the second summation term by the preset basic scaling factor to obtain the adaptive threshold value.

[0035] In one possible implementation, acquiring the vehicle's operating status parameters includes:

[0036] The vehicle's actual acceleration and attitude information are obtained through an inertial measurement unit;

[0037] The slope angle is obtained based on the actual acceleration and attitude information.

[0038] In one possible implementation, it also includes:

[0039] Wheel speed is obtained through wheel speed sensors and converted into vehicle speed;

[0040] The planned deceleration is received through the autonomous driving planning module or the longitudinal control module.

[0041] In one possible implementation, after determining the target deceleration, the process further includes:

[0042] The target deceleration is input into a preset first-order low-pass filter for smoothing to obtain the smoothed target deceleration.

[0043] Generate total deceleration control commands based on the smoothed target deceleration.

[0044] Secondly, embodiments of this application provide a deceleration determination device for downhill sections, the device comprising:

[0045] The acquisition module is used to acquire the vehicle's operating status parameters, including: planned deceleration, vehicle speed, and slope angle.

[0046] The safety margin calculation module is used to calculate the deceleration safety margin based on the difference between the preset deceleration upper limit and the planned deceleration.

[0047] The correction value calculation module is used to determine the deceleration correction value based on vehicle speed, slope angle, planned deceleration, and deceleration safety margin.

[0048] The determination module is used to determine the target deceleration based on the deceleration correction value and the planned deceleration.

[0049] In one possible implementation, the correction value calculation module is specifically used for:

[0050] Calculate the adaptive threshold value based on vehicle speed and slope angle;

[0051] The deceleration correction value is determined based on vehicle speed, slope angle, adaptive threshold, planned deceleration, and deceleration safety margin.

[0052] In one possible implementation, the correction value calculation module is further configured to:

[0053] Calculate the slope compensation deceleration based on the slope angle and gravitational acceleration;

[0054] The deceleration correction value is determined based on vehicle speed, slope compensation deceleration, adaptive threshold, planned deceleration, and deceleration safety margin.

[0055] In one possible implementation, the correction value calculation module is further configured to:

[0056] When the preset conditions are met, the deceleration correction value is determined to be zero;

[0057] The preset conditions are: the vehicle speed is greater than the preset vehicle speed, and the absolute value of the slope compensation deceleration is greater than the first product of the absolute value of the planned deceleration and the adaptive threshold value.

[0058] In one possible implementation, the correction value calculation module is further configured to:

[0059] When the preset conditions are not met, the slope correction coefficient is determined based on the slope compensation deceleration and the planned deceleration. The second product of the slope correction coefficient and the slope compensation deceleration is calculated, and the minimum value between the second product and the deceleration safety margin is taken as the deceleration correction value.

[0060] In one possible implementation, the correction value calculation module is further configured to:

[0061] Add the absolute value of the planned deceleration to the absolute value of the slope compensation deceleration to obtain the first summation term;

[0062] The ratio of the absolute value of the ramp compensation deceleration to the first summation term is determined as the ramp correction factor.

[0063] In one possible implementation, the correction value calculation module is further configured to:

[0064] Calculate the sine value of the slope angle;

[0065] The third product of gravitational acceleration and the sine value is used as the ramp compensation deceleration.

[0066] In one possible implementation, the correction value calculation module is further configured to:

[0067] Calculate the fourth product of the vehicle speed and the preset vehicle speed coefficient;

[0068] Calculate the fifth product of the absolute value of the slope angle and the preset slope coefficient;

[0069] The adaptive threshold value is determined based on the fourth product, the fifth product, and the preset basic scaling factor.

[0070] In one possible implementation, the correction value calculation module is further configured to:

[0071] Add the preset constant 1, the fourth product, and the fifth product together to obtain the second summation term;

[0072] Multiply the second summation term by the preset basic scaling factor to obtain the adaptive threshold value.

[0073] In one possible implementation, the acquisition module is specifically used for:

[0074] The vehicle's actual acceleration and attitude information are obtained through an inertial measurement unit;

[0075] The slope angle is obtained based on the actual acceleration and attitude information.

[0076] In one possible implementation, the acquisition module is further configured to:

[0077] Wheel speed is obtained through wheel speed sensors and converted into vehicle speed;

[0078] The planned deceleration is received through the autonomous driving planning module or the longitudinal control module.

[0079] In one possible implementation, the determining module is further configured to:

[0080] The target deceleration is input into a preset first-order low-pass filter for smoothing to obtain the smoothed target deceleration.

[0081] Generate total deceleration control commands based on the smoothed target deceleration.

[0082] Thirdly, this application provides a controller, including: a processor;

[0083] The processor is used to execute the downhill deceleration determination method provided in the first aspect of the invention, and to generate a total deceleration control command based on the target deceleration, so as to control the vehicle according to the total deceleration control command.

[0084] Fourthly, embodiments of this application provide a device for determining deceleration on a downhill section, comprising: a processor and a memory;

[0085] The memory stores instructions that the computer executes;

[0086] The processor executes computer execution instructions stored in the memory, causing the processor to perform the method for determining deceleration on a downhill section provided by the first aspect of the invention.

[0087] Fifthly, this application provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement a method for determining deceleration on a downhill section, as described in the first aspect of the invention.

[0088] Sixthly, this application provides a computer program product, including a computer program, which, when executed by a processor, is used to implement a method for determining deceleration on a downhill section, as described in the first aspect of the invention.

[0089] Based on the implementation methods provided in the above aspects, this application can be further combined to provide more implementation methods.

[0090] This application provides a method, controller, device, and medium for determining deceleration on downhill sections. By acquiring the vehicle's operating status parameters and calculating the deceleration safety margin based on the difference between the preset deceleration upper limit and the planned deceleration, the deceleration correction value is determined by combining the vehicle speed, slope angle, planned deceleration, and deceleration safety margin. The target deceleration is then determined based on the deceleration correction value and the planned deceleration. This method can coordinate and constrain the planned deceleration and dynamically correct it on downhill sections, suppressing total deceleration overshoot and control oscillations, thereby improving the vehicle's control smoothness, response rationality, and adaptability during the switching of different slope scenarios and operating conditions. Attached Figure Description

[0091] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0092] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0093] Figure 1 A schematic diagram illustrating the application scenario of the downhill deceleration determination method provided in this application;

[0094] Figure 2 A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 1 ;

[0095] Figure 3 A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 2 ;

[0096] Figure 4 A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 3 ;

[0097] Figure 5 A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 4 ;

[0098] Figure 6 A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 5 ;

[0099] Figure 7 This is a schematic diagram of a downhill deceleration determination device provided in an embodiment of this application;

[0100] Figure 8 This is a schematic diagram of a downhill deceleration determination device provided in an embodiment of this application. Detailed Implementation

[0101] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0102] In the embodiments of this application, the terms "first" and "second" are used to distinguish identical or similar items with substantially the same function and effect. Those skilled in the art will understand that the terms "first" and "second" do not limit the quantity or execution order, and that "first" and "second" do not necessarily imply difference. It should be noted that in the embodiments of this application, the words "exemplary" or "for example" are used to indicate that something is being used as an example, illustration, or description. Any embodiment or design scheme described as "exemplary" or "for example" in this application should not be construed as being better or more advantageous than other embodiments or design schemes. Specifically, the use of "exemplary" or "for example" is intended to present the relevant concepts in a concrete manner. In the embodiments of this application, "at least one" refers to one or more, and "more than one" refers to two or more.

[0103] It should be noted that the phrase "at...time" in the embodiments of this application can refer to the instant at which a certain situation occurs, or to a period of time after the occurrence of a certain situation; the embodiments of this application do not specifically limit this. Furthermore, the method for determining deceleration on a downhill section provided in the embodiments of this application is merely an example; a method for determining deceleration on a downhill section may include more or fewer elements.

[0104] Longitudinal control technology for autonomous vehicles is widely used on downhill sections such as urban roads, highways, park roads, and underground parking garage ramps. The relevant system typically includes a planning module, onboard sensors, and a control execution unit. The planning module outputs the planned deceleration, the sensors provide operating status parameters such as vehicle speed and gradient angle, and the control execution unit generates vehicle deceleration control commands based on these parameters.

[0105] In existing technologies, a common approach is to calculate the slope compensation deceleration and braking control quantity separately based on vehicle speed, gradient, and planned deceleration, and then superimpose the two before outputting them to the vehicle actuators. This type of solution typically relies on fixed thresholds, empirically calibrated parameters, or feedback correction mechanisms to adjust the compensation quantity to meet the deceleration requirements under different slope conditions.

[0106] However, in downhill braking scenarios, the slope-compensated deceleration and the planned deceleration are calculated independently and then directly added together, lacking coordination constraints for real-time operating conditions. This can easily cause the total deceleration to exceed the expected range. Especially when the vehicle speed is high, the slope is steep, or the planned deceleration is already close to its upper limit, the additional compensation may cause excessive braking, control oscillations, and sudden changes in commands during operating condition transitions, thereby affecting vehicle ride smoothness, passenger comfort, and braking safety.

[0107] Meanwhile, relying on feedback correction or preset thresholds often results in insufficient response to changes in vehicle speed, gradient, and planned deceleration, making it difficult to meet the control requirements of different downhill scenarios and limiting adaptability to multiple operating conditions.

[0108] Based on this, this application proposes a method for determining deceleration on downhill sections, applicable to the field of vehicle control technology, aiming to solve the aforementioned technical problems of the prior art. After obtaining the vehicle's planned deceleration, speed, and gradient angle, this method calculates a deceleration safety margin based on the difference between a preset deceleration upper limit and the planned deceleration. Then, it combines the vehicle speed, gradient angle, planned deceleration, and deceleration safety margin to determine a deceleration correction value, and finally determines the target deceleration based on the deceleration correction value and the planned deceleration. This method can be deployed in a vehicle control architecture consisting of a planning layer, sensors, and a control layer. By coordinating the relationships between relevant deceleration metrics under downhill conditions, it makes the target deceleration more closely match the real-time operating state, thereby helping to suppress total deceleration overshoot and improve the vehicle's adaptability on different downhill sections.

[0109] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will now be described with reference to the accompanying drawings.

[0110] To facilitate understanding, the following will be combined with... Figure 1 The application scenarios applicable to the embodiments of this application will be described.

[0111] Figure 1 This diagram illustrates an application scenario for the downhill deceleration determination method provided in this application. Please refer to [link / reference]. Figure 1 The application scenarios include: vehicle 110 and downhill road section 120.

[0112] Vehicle 110 can be any type of motor vehicle, such as a passenger car, commercial vehicle (e.g., truck, bus), or autonomous vehicle. Downhill section 120 refers to a terrain environment with a specific slope angle. In this environment, vehicle 110 is subjected to the component of gravity along the slope direction, which will produce a natural acceleration tendency or affect braking performance. In this embodiment, when vehicle 110 travels to downhill section 120, the onboard control system (such as an autonomous driving controller or chassis domain controller) can acquire the vehicle's operating status parameters (including planned deceleration, vehicle speed, and slope angle) in real time, and calculate the target deceleration based on the method provided in this application to offset or compensate for the dynamic effects of the downhill slope, ensuring that the vehicle can decelerate or maintain a stable speed according to the expected safety strategy.

[0113] Figure 2 A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 1 .like Figure 2 As shown, the method includes:

[0114] S201. Obtain the vehicle's operating status parameters.

[0115] The operating status parameters include: planned deceleration, vehicle speed, and gradient angle.

[0116] In this embodiment, the operating state parameters characterize the vehicle's current driving condition and serve as the input basis for subsequently determining the deceleration safety margin, deceleration correction value, and target deceleration. The planned deceleration represents the current target deceleration requirement, the vehicle speed reflects the vehicle's current speed, and the slope angle characterizes the road gradient.

[0117] In practical implementation, the executing entity of this method can be the longitudinal control unit in the vehicle controller, or the whole vehicle controller that communicates with the planning layer and the execution layer.

[0118] In one possible implementation, the planned deceleration, vehicle speed, and gradient angle can be processed synchronously to ensure that all inputs used in subsequent calculations belong to the same real-time operating condition. Based on the above analysis, after obtaining the vehicle's operating state parameters, a set of operating state parameters corresponding to the current control cycle can be generated, triggering the calculation of subsequent deceleration safety margins.

[0119] S202. Calculate the deceleration safety margin based on the difference between the preset deceleration upper limit and the planned deceleration.

[0120] In this embodiment, the deceleration safety margin is used to characterize the available deceleration margin between the preset deceleration upper limit and the planned deceleration, providing a safety boundary for the constraint of subsequent deceleration correction values.

[0121] The preset deceleration upper limit corresponds to the upper limit of the total deceleration that the vehicle is allowed to output under the current control strategy. This upper limit can be given by the vehicle calibration parameter table, or it can be preset in combination with the braking system capability, ride comfort boundary and scenario control level.

[0122] The planned deceleration reflects the current proposed deceleration requirements. Therefore, by subtracting the preset deceleration upper limit from the planned deceleration, we can obtain the remaining space that can still be allocated to the ramp correction portion without exceeding the total deceleration boundary. In this embodiment, the deceleration safety margin can be expressed as the preset deceleration upper limit minus the planned deceleration.

[0123] Specifically, the formula for calculating the deceleration safety margin is as follows:

[0124] S safe =a max -a plan

[0125] Among them, S safeTo provide a safety margin for deceleration, a max The preset upper limit for deceleration can be -0.4g, where g is the acceleration due to gravity, and a plan To slow down the planned pace.

[0126] Based on the above analysis, it can be seen that by establishing a direct relationship between the planned deceleration and the upper limit of the total deceleration, the subsequent correction calculations can always be controlled within the available boundary, thus ensuring that the target deceleration will not exceed the preset range due to the independent superposition of downhill corrections.

[0127] S203. Determine the deceleration correction value based on vehicle speed, slope angle, planned deceleration, and deceleration safety margin.

[0128] In this embodiment, the deceleration correction value is used to dynamically correct the planned deceleration so that the additional deceleration under downhill conditions does not deviate from the current vehicle state.

[0129] The process of determining the deceleration correction value can be combined with the vehicle speed, slope angle, planned deceleration, and deceleration safety margin for joint calculation, rather than directly and independently adding the slope-related correction amount to the planned deceleration.

[0130] In practice, the current downhill conditions characterized by vehicle speed and slope angle can be used as a basis to determine the correction results by combining the planned deceleration and deceleration safety margin, so that the deceleration correction value is linked with the real-time conditions and that the deceleration correction value never exceeds the boundary established by step S202, that is, it does not exceed the limit of the deceleration safety margin.

[0131] When the vehicle is in a downhill scenario with high speed, steep gradient, or already high planned deceleration, the deceleration correction value can be limited accordingly to reduce sudden changes in total deceleration. Regardless of the specific implementation method, the core of step S203 is to simultaneously incorporate vehicle speed, gradient angle, planned deceleration, and deceleration safety margin into the same correction link, so that the correction amount is linked with real-time operating conditions, and the deceleration correction value never exceeds the boundary established by step S202.

[0132] Based on the above analysis, it can be seen that this step can suppress the excessive superposition of high vehicle speed, steep gradient, and already high planned deceleration, and reduce the sudden change in total deceleration.

[0133] S204. Determine the target deceleration based on the deceleration correction value and the planned deceleration.

[0134] In this embodiment, the target deceleration is used as the final output deceleration control result, which is then used by the vehicle actuator to generate braking force or driving force adjustment commands. Specifically, the deceleration correction value obtained in step S203 can be combined with the planned deceleration in step S201 to obtain the target deceleration. This combination can be done by direct addition, so that the basic deceleration requirement and the correction amount under downhill conditions together form the final control quantity. If the deceleration correction value is zero, then the target deceleration equals the planned deceleration.

[0135] If the deceleration correction value does not reach the upper limit of the deceleration safety margin, the target deceleration is increased by the corresponding deceleration correction value based on the planned deceleration. Specifically, the formula for calculating the target deceleration is as follows:

[0136] a total =a plan +a final

[0137] Among them, a total To decelerate the target, a final This is the deceleration correction value.

[0138] If the deceleration correction value exceeds the deceleration safety margin, the increase in the target deceleration is limited to the allowable range of the deceleration safety margin, so that the final result does not exceed the preset deceleration upper limit.

[0139] Based on the above analysis, it can be seen that by combining the constrained deceleration correction value with the planned deceleration into a single target deceleration and outputting it to the execution layer, the deceleration command in the downhill scenario can be kept consistent with the real-time operating conditions, while the total deceleration can be kept within the preset boundary.

[0140] Based on the above analysis, this application provides a method for determining deceleration on downhill sections. The method includes acquiring vehicle operating state parameters, including planned deceleration, vehicle speed, and gradient angle; calculating a deceleration safety margin based on the difference between a preset deceleration upper limit and the planned deceleration; determining a deceleration correction value based on vehicle speed, gradient angle, planned deceleration, and deceleration safety margin; and determining a target deceleration based on the deceleration correction value and the planned deceleration. In this embodiment, by incorporating the planned deceleration, vehicle speed, gradient angle, and preset deceleration upper limit constraints into the same calculation chain, and using the deceleration safety margin as the correction boundary, the downhill deceleration correction value is coordinated. The target deceleration is not obtained by directly superimposing independent quantities, but rather formed under real-time operating condition constraints. Therefore, in downhill scenarios with high vehicle speed, steep gradient, or planned deceleration close to the preset deceleration upper limit, the deceleration correction value can be limited by changes in the deceleration safety margin, and the output amplitude and trend of the target deceleration remain under control.

[0141] Figure 3 A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 2 .like Figure 3 As shown in S203, based on vehicle speed, slope angle, planned deceleration, and deceleration safety margin, determine the deceleration correction value, including:

[0142] S31. Calculate the adaptive threshold value based on vehicle speed and slope angle.

[0143] The adaptive threshold value is adjusted according to vehicle speed and slope angle to ensure that the threshold can adapt to different downhill road conditions.

[0144] In practical implementation, the controller receives the vehicle speed signal from the vehicle speed sensor and the slope angle signal from the attitude sensor or slope estimation module, and calculates the adaptive threshold value based on a preset mapping relationship, lookup table relationship, or function expression. The mapping relationship can be established offline using calibration data. When the vehicle speed increases, the adaptive threshold value can be adjusted according to the corresponding relationship. When the slope angle changes, the adaptive threshold value is corrected synchronously, so that the adaptive threshold value reflects the current downhill intensity and vehicle motion state.

[0145] In some optional implementations, S31 above, calculating the adaptive threshold value based on vehicle speed and slope angle, includes:

[0146] S311. Calculate the fourth product of the vehicle speed and the preset vehicle speed coefficient.

[0147] S312. Calculate the fifth product of the absolute value of the slope angle and the preset slope coefficient.

[0148] S313. Determine the adaptive threshold value based on the fourth product, the fifth product, and the preset basic scaling factor.

[0149] Among them, the preset speed coefficient is a pre-calibrated proportional parameter used to characterize the influence of speed changes on the adaptive threshold adjustment. The preset slope coefficient is a proportional parameter related to slope changes, used to adjust the contribution of slope to the adaptive threshold. The preset base proportional coefficient is a fixed benchmark parameter used to set the overall benchmark for the adaptive threshold, ensuring that the adaptive threshold maintains a stable basic scale under different speeds and slope conditions.

[0150] In actual calculations, after receiving the vehicle speed and slope angle, the controller first multiplies the vehicle speed by a preset speed coefficient to obtain a fourth product reflecting the speed's influence. Then, it multiplies the absolute value of the slope angle by a preset slope coefficient to obtain a fifth product reflecting the slope's influence. Subsequently, the controller combines the fourth and fifth products with a preset base proportional coefficient to calculate an adaptive threshold value. This adaptive threshold value serves as the basis for subsequent deceleration correction, slope compensation constraints, or command limits, and its value adjusts synchronously as vehicle speed or slope increases. Each coefficient can be set during calibration based on the vehicle's wheelbase, braking response characteristics, and downhill scenario requirements.

[0151] By incorporating both vehicle speed and gradient factors into the threshold calculation, the resulting adaptive threshold value can vary with operating conditions and, together with a preset base proportional coefficient, form a stable constraint boundary. This makes the subsequent deceleration correction value calculation more consistent with real-time downhill scenarios. With this approach, the adaptive threshold value is not fixed, providing more suitable constraints at higher vehicle speeds or steeper gradients. Consequently, the generation of total deceleration control commands is more continuous, and the control results better reflect the vehicle's current operating state.

[0152] In some optional implementations, S313 above, determining the adaptive threshold value based on the fourth product, the fifth product, and a preset base scaling factor, includes:

[0153] S3131. Add the preset constant 1, the fourth product and the fifth product to obtain the second summation term.

[0154] S3132. Multiply the second summation term by the preset basic proportional coefficient to obtain the adaptive threshold value.

[0155] The second summation term characterizes the synthesis result of the vehicle speed-related term, the slope-related term, and the constant term. This synthesis result serves as an intermediate quantity for subsequent scaling in determining the adaptive threshold value. The preset base scaling coefficient can be a pre-calibrated scaling parameter stored in the vehicle controller. Its value can be set according to the vehicle model's braking response characteristics, longitudinal control calibration results, and slope scenario adaptation requirements.

[0156] In practical implementation, after receiving the vehicle speed and gradient angle, the controller can first generate a fourth product and a fifth product. The fourth product is obtained by multiplying the vehicle speed by a preset speed coefficient, and the fifth product is obtained by multiplying the absolute value of the gradient angle by a preset gradient coefficient. These two products are then added to a preset constant 1 to form a second summation term. Subsequently, this second summation term is multiplied by a preset base proportional coefficient to output an adaptive threshold value. This adaptive threshold value, as a threshold that varies with vehicle speed and gradient, can be input into subsequent deceleration coordination calculations to characterize the boundary range within which corrections can be triggered under different downhill conditions.

[0157] Specifically, the formula for calculating the adaptive threshold is as follows:

[0158]

[0159] in, For adaptive threshold, To preset the basic scaling factor, for example, it can be 0.2, k v / 100 is the preset vehicle speed coefficient, and v is the vehicle speed. To preset the slope coefficient, The slope angle is denoted by .

[0160] The preset speed coefficient and preset gradient coefficient can be pre-calibrated proportional parameters, such as k. v / 100=0.3 / 100=0.003; =0.02.

[0161] In one embodiment, both the preset vehicle speed coefficient and the preset gradient coefficient can be calibrated using a real vehicle or a high-precision vehicle dynamics simulation platform. The specific calibration process may include the following steps:

[0162] First, a calibration environment must be set up and testing equipment configured. In real-vehicle testing, a high-precision Differential Global Positioning System (GPS) is required for accurate speed measurement, with an accuracy of, for example, ±0.1 kilometers per hour (km / h). A gyroscope or tilt sensor is also needed for accurate slope angle measurement, with an accuracy of, for example, ±0.1 degrees. Brake pressure sensors and accelerometers are also required. If a simulation platform is used, a high-precision vehicle dynamics model must be established to simulate the output signals of the aforementioned sensors.

[0163] Next, the preset speed coefficient is calibrated. A fixed slope (e.g., a slope angle of 5 degrees) can be selected, and multiple different test speeds can be set (e.g., 20 km / h, 40 km / h, 60 km / h, 80 km / h, 100 km / h). A fixed planned deceleration is applied at each test speed, for example, -0.8 meters per second squared (m / s²). 2 In this process, it is necessary to determine the actual critical threshold α at the current vehicle speed. actual .

[0164] Specifically, this can be achieved by obtaining the absolute value of the slope compensation deceleration at the current slope. With the absolute value of the applied planned deceleration The ratio of the two is calculated to obtain the value of the ratio of the two. Record the actual critical thresholds at different vehicle speeds, and use the formula... The data is fitted to determine the preset vehicle speed coefficient k. v / 100. In typical calibration results, k v The value range can be 0.3±0.05.

[0165] Next, the preset slope coefficient is calibrated. A fixed vehicle speed (e.g., 60 km / h) is selected, and multiple different slope angles (e.g., 2 degrees, 4 degrees, 6 degrees, 8 degrees, 10 degrees) are set, while a fixed planned deceleration is applied. During this process, the actual critical threshold α under the current slope needs to be determined. actual .

[0166] Specifically, this can be achieved by obtaining the absolute value of the slope compensation deceleration at the current slope. With the absolute value of the applied planned deceleration The ratio of the two is calculated to obtain the value of the ratio of the two. Record the actual critical thresholds under different slopes, and use the formula... The data is fitted to determine the preset slope coefficient. In typical calibration results, The value range can be 0.02 ± 0.005 per degree.

[0167] Finally, joint verification and fine-tuning were performed. The calibrated preset vehicle speed coefficient and preset gradient coefficient were substituted into the complete adaptive threshold calculation formula. In the process, real vehicle or simulation verification is carried out in a wider range of working conditions, and the preset vehicle speed coefficient and preset slope coefficient are fine-tuned according to the verification results until the system performance meets the design requirements under all working conditions.

[0168] During operation, the adaptive threshold value is jointly determined by the vehicle speed term, the gradient term, and a preset basic proportional coefficient. When the vehicle speed increases or the gradient angle increases, the second summation term changes accordingly, and the adaptive threshold value is adjusted accordingly to match the current road gradient and vehicle operating state. This adaptive threshold value can further participate in the determination process of the deceleration correction value, thereby keeping the coordination relationship between the slope compensation deceleration and the planned deceleration within the preset constraint range.

[0169] After adopting the above implementation method, the adaptive threshold no longer depends on a single fixed threshold, but can change synchronously with vehicle speed and slope angle. Therefore, the deceleration correction process can have a more stable adaptability to downhill conditions, and the subsequent target deceleration generation results are more in line with the real-time operating state.

[0170] S32. Determine the deceleration correction value based on vehicle speed, slope angle, adaptive threshold, planned deceleration, and deceleration safety margin.

[0171] During operation, the vehicle controller can dynamically update the adaptive threshold value based on real-time vehicle speed and slope angle. This adaptive threshold value is then used to constrain the superposition relationship between the planned deceleration and the slope compensation deceleration, outputting a deceleration correction value. Thus, the deceleration correction value can adaptively change with operating conditions and limit the compensation amplitude on downhill sections, ensuring that the final target deceleration remains within a preset range.

[0172] After adopting the above method, the determination of the deceleration correction value no longer depends on a fixed threshold, but is determined by the vehicle speed and the slope angle. The adaptive threshold value is used to limit the slope compensation deceleration, so the correction amount can match the real-time operating conditions better, reduce the overshoot after deceleration superposition, and improve the consistency and smoothness of control commands under different slope sections.

[0173] In some optional implementations, the above-mentioned step S32, determining the deceleration correction value based on vehicle speed, slope angle, adaptive threshold, planned deceleration, and deceleration safety margin, includes:

[0174] S321. Calculate the slope compensation deceleration based on the slope angle and gravitational acceleration.

[0175] Among them, gravitational acceleration is used as the physical reference quantity for conversion. The commonly used standard gravitational acceleration value on the Earth's surface can be taken. By combining the slope angle and gravitational acceleration, the slope compensation deceleration corresponding to the current slope can be obtained.

[0176] Vehicle speed can be obtained from wheel speed sensors, wheel speed fusion signals, or on-board speed estimation modules. The adaptive threshold value can be generated based on the coupling relationship between the current vehicle speed and the slope angle, and is used to limit the trigger range for slope compensation deceleration to participate in the correction.

[0177] In some optional implementations, S321 above, calculating the ramp compensation deceleration based on the slope angle and gravitational acceleration, includes:

[0178] S3211. Calculate the sine value of the slope angle.

[0179] S3212. The third product of gravitational acceleration and the sine value is used as the ramp compensation deceleration.

[0180] Among them, the sine value is a dimensionless quantity obtained by trigonometric function operation of the slope angle, and the third product is an intermediate result obtained by multiplying the gravitational acceleration by the sine value of the slope angle.

[0181] In practice, after receiving the slope angle signal, the vehicle controller can perform a sine calculation on the slope angle through the trigonometric function calculation module, and multiply the calculation result by the preset or real-time calibrated gravity acceleration parameter to obtain the slope compensation deceleration.

[0182] Specifically, the formula for calculating ramp compensation deceleration is as follows:

[0183]

[0184] Among them, a slope Here, g is the deceleration due to the ramp, and g is the acceleration due to gravity.

[0185] The gravitational acceleration parameter can be taken as the standard gravitational acceleration at the Earth's surface, or it can be corrected according to the gravity environment of the area where the vehicle is deployed. The calculated slope compensation deceleration can be used as the basic input for subsequent deceleration correction and total deceleration control command generation, and participates in the generation of target deceleration on downhill sections.

[0186] This method directly uses the sine value of the slope angle and gravitational acceleration to generate slope compensation deceleration, establishing a correspondence between the slope compensation deceleration and the slope geometry. This provides a definite physical quantity input for subsequent deceleration coordination. As a result, the compensation calculation process in slope scenarios is more explicit, and the output results can be easily synthesized with the planned deceleration to form a total deceleration control command.

[0187] S322. Determine the deceleration correction value based on vehicle speed, slope compensation deceleration, adaptive threshold value, planned deceleration, and deceleration safety margin.

[0188] In practice, after receiving the vehicle's real-time speed, real-time slope angle, and planned deceleration, the controller can first calculate the slope compensation deceleration based on the slope angle and gravitational acceleration. Then, the slope compensation deceleration, along with the vehicle speed, adaptive threshold, planned deceleration, and deceleration safety margin, are input into the correction formula, and the deceleration correction value is output.

[0189] The correction formula can be implemented by looking up a table, segmented mapping, or arithmetic operations, so that when the vehicle speed increases, the gradient increases, or the planned deceleration approaches the upper limit, the correction result can be kept within a controllable range by adaptive threshold values ​​and safety margin constraints.

[0190] This method first generates a slope-compensated deceleration under downhill conditions, then adjusts the planned deceleration by combining real-time vehicle speed and threshold constraints. This ensures that the deceleration correction value matches the current road gradient and vehicle operating state, making the subsequent target deceleration more consistent with the longitudinal control requirements of the vehicle along the road direction. Because the deceleration safety margin is involved in the constraints, the correction result will not directly exceed the preset control boundary, thus making the braking command smoother and exhibiting better adaptability to different gradients and vehicle speeds.

[0191] In some optional implementations, S322 above, determining the deceleration correction value based on vehicle speed, slope-compensated deceleration, adaptive threshold, planned deceleration, and deceleration safety margin, includes:

[0192] S3221. When the preset conditions are met, the deceleration correction value is determined to be zero.

[0193] The preset conditions are: the vehicle speed is greater than the preset vehicle speed, and the absolute value of the slope compensation deceleration is greater than the first product of the absolute value of the planned deceleration and the adaptive threshold value.

[0194] Specifically, the preset vehicle speed is used to characterize the speed threshold that triggers the judgment. When the real-time vehicle speed exceeds the threshold, it indicates that the vehicle is in a high-speed operating condition.

[0195] In actual implementation, after the controller obtains the vehicle speed, slope angle and planned deceleration, it can first determine the adaptive threshold value based on the vehicle speed and slope angle, then calculate the slope compensation deceleration based on the slope angle and gravitational acceleration, then calculate the first product of the absolute value of the planned deceleration and the adaptive threshold value, and compare the absolute value of the slope compensation deceleration with the first product.

[0196] When the detected vehicle speed exceeds the preset speed and the absolute value of the slope compensation deceleration exceeds the first product, the controller can directly set the deceleration correction value to zero without adding any additional correction, and then output the control result corresponding to the planned deceleration. In practical applications, this controller can also be implemented using an on-board domain controller, a brake control unit, or a computing platform with longitudinal control capabilities; this application embodiment does not limit this.

[0197] This approach directly suppresses deceleration correction values ​​at high vehicle speeds and when gradient compensation deceleration is excessive, thus preventing the target deceleration from introducing additional corrections. By incorporating vehicle speed thresholds, gradient compensation intensity, and adaptive thresholds into the decision criteria, the control output can remain stable under steep slope and high-speed conditions, and the deceleration coordination relationship under different gradient scenarios can be more clearly defined.

[0198] By adopting the above method, the deceleration correction value can be quickly set to zero when the preset conditions are met, reducing the excessive braking command caused by the superposition of slope compensation deceleration and planned deceleration, making the control output more in line with the current driving state, and improving the consistency and smoothness of deceleration control on downhill sections.

[0199] S3222. When the preset conditions are not met, determine the slope correction coefficient based on the slope compensation deceleration and the planned deceleration, calculate the second product of the slope correction coefficient and the slope compensation deceleration, and take the minimum value between the second product and the deceleration safety margin as the deceleration correction value.

[0200] The slope correction factor is used to scale the slope compensation deceleration, and its value is matched to the relative relationship between the slope compensation deceleration and the planned deceleration. The second product is an intermediate value obtained by multiplying the slope correction factor by the slope compensation deceleration, which serves as a candidate deceleration correction amount for subsequent comparisons.

[0201] In practical implementation, after determining that the preset conditions are not met, the controller can first determine a slope correction coefficient based on the relationship between the current slope compensation deceleration and the planned deceleration. This slope correction coefficient reflects the degree of coordination between the compensation requirements and the planned requirements. Then, the slope correction coefficient is multiplied by the slope compensation deceleration to obtain a second product. Subsequently, the controller can compare the second product with the deceleration safety margin and select the smaller one as the deceleration correction value for output, thus forming a constrained compensation result. In this process, the slope correction coefficient can be obtained from a calibration table, function mapping, or piecewise calculation.

[0202] It should be noted that comparing the second product with the deceleration safety margin and selecting the smaller one as the deceleration correction value output here means taking the absolute value of both the second product and the deceleration safety margin, and then comparing their numerical values.

[0203] Specifically, the formula for calculating the deceleration correction value is as follows:

[0204]

[0205] Where K is the slope correction factor.

[0206] In this embodiment, the second product, as a proportionally scaled compensation amount, together with the deceleration safety margin, forms a limiting comparison relationship, ensuring that the output deceleration correction value is always constrained by the deceleration safety margin and does not exceed its range. Therefore, the deceleration correction value can meet the gradient compensation requirements while remaining within the allowable range, and forms coordinated control with the upper-level planned deceleration, thereby making the longitudinal deceleration control of downhill sections more stable and consistent.

[0207] Figure 4A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 3 .like Figure 4 As shown in S3222, determine the slope correction coefficient based on the slope compensation deceleration and the planned deceleration, including:

[0208] S401. Add the absolute value of the planned deceleration to the absolute value of the slope compensation deceleration to obtain the first summation term.

[0209] S402. The ratio of the absolute value of the ramp compensation deceleration to the first summation term is determined as the ramp correction coefficient.

[0210] The first summation term is used to synthesize the two types of deceleration requirements and serves as an intermediate quantity for subsequent normalization calculations.

[0211] In its implementation, after receiving the planned deceleration output by the planning module, the vehicle controller can simultaneously acquire the slope compensation deceleration calculated by the inertial measurement unit or based on the slope angle and gravitational acceleration, and take the absolute values ​​of each for calculation. The controller can add the two to obtain a first summation term, and then divide the absolute value of the slope compensation deceleration by the first summation term to obtain a slope correction coefficient between zero and one. This slope correction coefficient can be calculated in real time by an arithmetic unit, which can be integrated into the vehicle domain controller, brake controller, or a separate longitudinal control chip, using fixed-point or floating-point arithmetic.

[0212] When the slope is steep, the proportion of the slope compensation deceleration in the first summation term increases, resulting in a larger slope correction coefficient. When the planned deceleration dominates, the slope correction coefficient decreases accordingly. The controller adjusts the slope compensation deceleration proportionally to ensure it remains consistent with the planned deceleration during subsequent deceleration corrections, and outputs the calculation results to the target deceleration generation module.

[0213] Specifically, the formula for calculating the slope correction factor is as follows:

[0214]

[0215] Through the above calculation method, the slope correction coefficient can dynamically change with the relative relationship between the planned deceleration and the slope compensation deceleration, so that the participation of the slope compensation deceleration is matched with the current downhill working condition. This makes the subsequent deceleration correction value more in line with the real-time longitudinal control requirements of the vehicle and improves the adaptability and control consistency under different slope conditions.

[0216] Figure 5 A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 4 .like Figure 5As shown, S201, acquire the vehicle's operating status parameters, including:

[0217] S501. Obtain the vehicle's actual acceleration and attitude information through the inertial measurement unit.

[0218] S502. Based on the actual acceleration and attitude information, the slope angle is obtained.

[0219] S503: Obtain wheel speed through wheel speed sensor and convert wheel speed into vehicle speed.

[0220] S504 receives the planned deceleration through the automatic driving planning module or the longitudinal control module.

[0221] The inertial measurement unit (IMU) can be integrated into the vehicle chassis, body controller, or independent sensor module. It typically consists of an accelerometer, a gyroscope, and necessary signal processing circuitry. It is used to output the vehicle's acceleration components in the longitudinal, lateral, and vertical directions, as well as attitude information such as pitch, roll, and yaw angles.

[0222] After acquiring the actual acceleration and attitude information, the slope angle of the current road segment can be obtained based on the attitude transformation relationship between the vehicle coordinate system and the geographic coordinate system. Specifically, the actual acceleration components and attitude information can be fused, and combined with the projection relationship of gravitational acceleration in the vehicle coordinate system, the tilt angle of the vehicle along the road slope can be calculated, thus obtaining the slope angle value. This slope angle can be used as the input of the operating state parameters in the subsequent deceleration determination process, providing basic data for the calculation of control quantities under downhill conditions.

[0223] In this way, the actual acceleration and attitude information output by the inertial measurement unit can be directly used to obtain the slope angle, eliminating the reliance on external slope sensors and enabling the slope angle to be updated in real time with changes in vehicle attitude. When using this slope angle in subsequent deceleration calculations, the control quantity can be more closely aligned with the vehicle's current road conditions, and the continuity and consistency of obtaining operating state parameters for downhill sections can be improved.

[0224] Furthermore, the wheel speed sensor is a speed acquisition component located near the vehicle wheels. Its output signal represents the wheel rotation frequency or angular velocity, and the wheel speed can be converted into vehicle speed by the on-board controller according to the effective rolling circumference of the tire, the transmission ratio, or the calibration conversion factor.

[0225] In practice, wheel speed sensors can be magnetoelectric, Hall effect, or encoder sensors. They are installed near the wheel hubs or brake components of each wheel. The collected wheel speeds are filtered by the vehicle controller to form a stable vehicle speed signal, which is then used as an input parameter in the deceleration determination process for downhill sections.

[0226] The planned deceleration can be generated by the autonomous driving planning module based on road curvature, the speed of vehicles ahead, and traffic constraints, and sent to the longitudinal control module via the vehicle communication bus, or directly received by the longitudinal control module from the upper-level control commands, so that the planned deceleration can be used as the basis for subsequent deceleration safety margin calculation and deceleration correction calculation.

[0227] Specifically, wheel speed sensors first acquire wheel rotation speeds in real time and convert them into vehicle speed. Then, the autonomous driving planning module or longitudinal control module provides the planned deceleration. Subsequently, the vehicle speed and the planned deceleration are sent to the downhill section deceleration determination logic for collaborative processing, thereby forming a target deceleration suitable for the current slope conditions. Since the vehicle speed is derived from the direct conversion of wheel speed signals, and the planned deceleration comes from the upper-level output of the control system, both can be updated in real time, thus maintaining the continuity and consistency of deceleration input.

[0228] After adopting the above implementation method, both vehicle speed and planned deceleration can be stably obtained in the vehicle control link, and the vehicle speed conversion relationship is clear, which is convenient to participate in deceleration correction together with slope-related parameters. This ensures that the output target deceleration maintains a good matching relationship with the current downhill conditions and reduces deceleration deviation caused by unstable input sources.

[0229] Figure 6 A flowchart illustrating a method for determining deceleration on a downhill section, provided in this application embodiment. Figure 5 .like Figure 6 As shown, after determining the target deceleration based on the deceleration correction value and the planned deceleration in S204, the following steps are also included:

[0230] S601. Input the target deceleration into a preset first-order low-pass filter for smoothing to obtain the smoothed target deceleration.

[0231] S602. Generate total deceleration control command based on the smoothed target deceleration.

[0232] The total deceleration control command is the actual control output for the braking system or power system. The controller can generate the total deceleration control command based on the smoothed target deceleration and send it to the vehicle actuators.

[0233] In this embodiment, after obtaining the target deceleration, the controller first performs filtering operations on the input to a preset first-order low-pass filter, converting the deceleration signal, which may have abrupt changes, into a smooth, continuously changing signal. The final total deceleration control command is then formed based on this smooth signal. This total deceleration control command can be further converted into a braking pressure request, regenerative braking request, or torque request, and sent by the vehicle controller to the corresponding execution unit to complete the longitudinal deceleration adjustment. The time constant of the filter can be set according to the vehicle type, control cycle, and braking system response characteristics. In practical applications, other equivalent low-pass implementations can also be selected for the filter; this embodiment does not specifically limit this.

[0234] After adopting this method, the variation range of the total deceleration control command is smoothly constrained, the sudden change of the command is suppressed, the deceleration output of the vehicle in the downhill condition is more continuous, the oscillation and impact during the control execution process are reduced, and the connection between the target deceleration and the actuator is more stable.

[0235] In a specific scenario of a downhill section of a highway, assuming a vehicle speed v = 80 km / h and a gradient angle θ = -6 degrees, the planned deceleration a is... plan =-0.9m / s 2 Gradient compensation deceleration a slope =g×sinθ=-1.02m / s 2 .

[0236] The adaptive threshold value is:

[0237]

[0238] Accordingly, m / s 2 .

[0239] because Then the deceleration correction value a final =0, the final target deceleration is -0.9 m / s². 2 .

[0240] In another specific urban road gentle slope cruising scenario, assuming the vehicle speed v = 50 km / h and the slope angle θ = -0.7 degrees (downhill), the planned deceleration a plan =-0.6m / s 2 The acceleration due to gravity is g = 9.8 m / s². 2 .

[0241] The ramp compensation deceleration is:

[0242]

[0243] The adaptive threshold value is: =0.2×(1+0.3×50 / 100+0.02×0.7)=0.2328.

[0244] Accordingly, m / s 2 .

[0245] because If the preset conditions are not met, the deceleration correction value is not 0. At this time, the deceleration correction value K = 0.120 / (0.120+0.6) = 0.167.

[0246] Then K×a slope =0.167×(-0.120)=-0.020m / s 2 .

[0247] The final target deceleration is a total =a plan +a final =-0.6+(-0.020)=-0.620m / s 2 .

[0248] The method in this application embodiment can effectively suppress the deceleration overshoot caused by directly superimposing the planned deceleration and the slope compensation deceleration in traditional methods. At the start of the slope, after dynamic proportional threshold judgment and slope correction coefficient calculation, the deceleration correction value is significantly reduced. After a first-order inertial smooth transition, the total deceleration stabilizes at -0.620 m / s². 2 The target deceleration slope exhibits a smooth transition near the starting point, without any abrupt changes.

[0249] Furthermore, embodiments of this application also provide a controller, including: a processor.

[0250] The processor is used to execute the downhill deceleration determination method provided above, and to generate a total deceleration control command based on the target deceleration, so as to control the vehicle according to the total deceleration control command.

[0251] When the processor is deployed in the vehicle control architecture, it can invoke the downhill deceleration determination method to jointly process the planned deceleration output by the planning module and the vehicle speed and slope angle provided by the sensors. It then forms a deceleration safety margin based on the difference between the preset deceleration upper limit and the planned deceleration, and combines the vehicle speed, slope angle, planned deceleration, and deceleration safety margin to determine the target deceleration. The processor can further generate a total deceleration control command based on the target deceleration and apply it to the vehicle. This prevents the downhill compensation requirement from being simply and independently superimposed with the planned deceleration requirement, thus coordinating and constraining the total deceleration. This suppresses deceleration overshoot, excessive braking, and sudden command changes during high speeds, steep slopes, or changes in operating conditions, thereby improving the smoothness of vehicle longitudinal control, ride comfort, and braking safety. Therefore, it helps improve the vehicle's adaptability to different downhill scenarios such as urban roads, highways, park roads, and underground parking garage ramps.

[0252] This application embodiment can divide the downhill deceleration determination device or main control device into functional modules according to the above method example. For example, each function can be divided into a separate functional module, or two or more functions can be integrated into one processing unit. The integrated unit can be implemented in hardware or as a software functional module. It should be noted that the module division in this embodiment is illustrative and only represents one logical functional division; other division methods may be used in actual implementation.

[0253] Figure 7 This is a schematic diagram of a downhill deceleration determination device provided in an embodiment of this application. Figure 7 As shown, the device includes: an acquisition module 710, a safety margin calculation module 720, a correction value calculation module 730, and a determination module 740.

[0254] The acquisition module 710 is used to acquire the vehicle's operating status parameters, including: planned deceleration, vehicle speed, and slope angle.

[0255] The safety margin calculation module 720 is used to calculate the deceleration safety margin based on the difference between the preset deceleration upper limit and the planned deceleration.

[0256] The correction value calculation module 730 is used to determine the deceleration correction value based on vehicle speed, slope angle, planned deceleration, and deceleration safety margin.

[0257] The determination module 740 is used to determine the target deceleration based on the deceleration correction value and the planned deceleration.

[0258] In one possible implementation, the correction value calculation module 730 is specifically used for:

[0259] Calculate the adaptive threshold value based on vehicle speed and slope angle.

[0260] The deceleration correction value is determined based on vehicle speed, slope angle, adaptive threshold, planned deceleration, and deceleration safety margin.

[0261] In one possible implementation, the correction value calculation module 730 is further configured to:

[0262] Calculate the slope compensation deceleration based on the slope angle and gravitational acceleration.

[0263] The deceleration correction value is determined based on vehicle speed, slope compensation deceleration, adaptive threshold, planned deceleration, and deceleration safety margin.

[0264] In one possible implementation, the correction value calculation module 730 is further configured to:

[0265] When the preset conditions are met, the deceleration correction value is determined to be zero.

[0266] The preset conditions are: the vehicle speed is greater than the preset vehicle speed, and the absolute value of the slope compensation deceleration is greater than the first product of the absolute value of the planned deceleration and the adaptive threshold value.

[0267] In one possible implementation, the correction value calculation module 730 is further configured to:

[0268] When the preset conditions are not met, the slope correction coefficient is determined based on the slope compensation deceleration and the planned deceleration. The second product of the slope correction coefficient and the slope compensation deceleration is calculated, and the minimum value between the second product and the deceleration safety margin is taken as the deceleration correction value.

[0269] In one possible implementation, the correction value calculation module 730 is further configured to:

[0270] Add the absolute value of the planned deceleration to the absolute value of the slope compensation deceleration to obtain the first summation term.

[0271] The ratio of the absolute value of the ramp compensation deceleration to the first summation term is determined as the ramp correction factor.

[0272] In one possible implementation, the correction value calculation module 730 is further configured to:

[0273] Calculate the sine of the slope angle.

[0274] The third product of gravitational acceleration and the sine value is used as the ramp compensation deceleration.

[0275] In one possible implementation, the correction value calculation module 730 is further configured to:

[0276] Calculate the fourth product of the vehicle speed and the preset vehicle speed coefficient;

[0277] Calculate the fifth product of the absolute value of the slope angle and the preset slope coefficient.

[0278] The adaptive threshold value is determined based on the fourth product, the fifth product, and the preset basic scaling factor.

[0279] In one possible implementation, the correction value calculation module 730 is further configured to:

[0280] Add the preset constant 1, the fourth product, and the fifth product to obtain the second summation term.

[0281] Multiply the second summation term by the preset basic scaling factor to obtain the adaptive threshold value.

[0282] In one possible implementation, the acquisition module 710 is specifically used for:

[0283] The vehicle's actual acceleration and attitude information are obtained through an inertial measurement unit.

[0284] The slope angle is obtained based on the actual acceleration and attitude information.

[0285] In one possible implementation, the acquisition module 710 is further configured to:

[0286] Wheel speed is obtained through wheel speed sensors and converted into vehicle speed.

[0287] The planned deceleration is received through the autonomous driving planning module or the longitudinal control module.

[0288] In one possible implementation, the determining module 740 is further configured to:

[0289] The target deceleration is input into a preset first-order low-pass filter for smoothing to obtain the smoothed target deceleration.

[0290] Generate total deceleration control commands based on the smoothed target deceleration.

[0291] The downhill deceleration determination device provided in this embodiment can execute the downhill deceleration determination method of the above embodiment. Its implementation principle and technical effect are similar, and will not be described again in this embodiment.

[0292] In the specific implementation of the aforementioned downhill deceleration determination device, each module can be implemented as a processor. The processor can execute computer execution instructions stored in the memory, causing the processor to execute the aforementioned downhill deceleration determination method.

[0293] Figure 8 This is a schematic diagram of a downhill deceleration determination device provided in an embodiment of this application. Figure 8 As shown, the downhill deceleration determination device includes at least one processor 810 and a memory 820. The downhill deceleration determination device also includes a communication component 830. The processor 810, memory 820, and communication component 830 are connected via a bus 840.

[0294] In the specific implementation process, at least one processor 810 executes computer execution instructions stored in memory 820, causing at least one processor 810 to execute a downhill deceleration determination method as executed by the downhill deceleration determination device.

[0295] The specific implementation process of processor 810 can be found in the above method embodiments, and its implementation principle and technical effect are similar. It will not be repeated here.

[0296] In the above embodiments, it should be understood that the processor can be a Central Processing Unit (CPU), or other general-purpose processors, digital signal processors (DSPs), application-specific integrated circuits (ASICs), etc. The general-purpose processor can be a microprocessor or any conventional processor. The steps of the method disclosed in this invention can be directly implemented by a hardware processor, or implemented by a combination of hardware and software modules within the processor.

[0297] The memory may include high-speed RAM, and may also include non-volatile storage (NVM), such as at least one disk storage.

[0298] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus, etc. Buses can be categorized as address buses, data buses, control buses, etc. For ease of illustration, the buses shown in the accompanying drawings are not limited to a single bus or a single type of bus.

[0299] The above description of the functions implemented by the downhill deceleration determination device and the main control device illustrates the solution provided by the embodiments of the present invention. It is understood that, in order to achieve the above functions, the downhill deceleration determination device or the main control device includes hardware structures and / or software modules corresponding to the execution of each function. By combining the units and algorithm steps of the various examples described in the embodiments of the present invention, the embodiments of the present invention can be implemented in hardware or a combination of hardware and computer software. Whether a function is executed by hardware or by computer software driving hardware 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 implementation should not be considered beyond the scope of the technical solution of the embodiments of the present invention.

[0300] This application also provides a computer-readable storage medium storing computer-executable instructions, which, when executed by a processor, are used to implement the above-described method for determining deceleration on a downhill section.

[0301] The aforementioned readable storage medium can be implemented by any type of volatile or non-volatile storage device or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The readable storage medium can be any available medium accessible to a general-purpose or special-purpose computer.

[0302] An exemplary readable storage medium is coupled to a processor, enabling the processor to read information from and write information to the readable storage medium. Alternatively, the readable storage medium can be an integral part of the processor. Both the processor and the readable storage medium can reside in an Application Specific Integrated Circuit (ASIC). Alternatively, the processor and the readable storage medium can exist as discrete components in a downhill deceleration determination device or a main control device.

[0303] This application also provides a computer program product, which includes a computer program stored in a readable storage medium. At least one processor of the downhill deceleration determination device can read the computer program from the readable storage medium, and the at least one processor executes the computer program to cause the downhill deceleration determination device to perform the solution provided in the above embodiments.

[0304] Those skilled in the art will understand that all or part of the steps of the above method embodiments can be implemented by hardware related to program instructions. The aforementioned program can be stored in a computer-readable storage medium. When the program is executed, it performs the steps of the above method embodiments; and the aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disk, or optical disk.

[0305] The technical solutions of this application have been described above with reference to the preferred embodiments shown in the accompanying drawings. However, it is readily understood by those skilled in the art that the scope of protection of this application is obviously not limited to these specific embodiments. The above embodiments are only used to illustrate the technical solutions of this application and are not intended to limit them. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. These modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this application.

Claims

1. A method of determining deceleration for a downhill section of a road, characterized by, include: Obtain the vehicle's operating status parameters, including: planned deceleration, vehicle speed, and slope angle; Calculate the deceleration safety margin based on the difference between the preset deceleration upper limit and the planned deceleration; The deceleration correction value is determined based on the vehicle speed, the slope angle, the planned deceleration, and the deceleration safety margin. The target deceleration is determined based on the deceleration correction value and the planned deceleration.

2. The method of claim 1, wherein, The determination of the deceleration correction value includes: Calculate the adaptive threshold value based on the vehicle speed and the slope angle; The deceleration correction value is determined based on the vehicle speed, the slope angle, the adaptive threshold, the planned deceleration, and the deceleration safety margin.

3. The method of claim 2, wherein, The determination of the deceleration correction value includes: Calculate the ramp compensation deceleration based on the slope angle and gravitational acceleration. The deceleration correction value is determined based on the vehicle speed, the slope compensation deceleration, the adaptive threshold, the planned deceleration, and the deceleration safety margin.

4. The method of claim 3, wherein, The determination of the deceleration correction value includes: When the preset conditions are met, the deceleration correction value is determined to be zero; The preset conditions are: the vehicle speed is greater than the preset vehicle speed, and the absolute value of the slope compensation deceleration is greater than the first product of the absolute value of the planned deceleration and the adaptive threshold value.

5. The method of claim 4, wherein, Also includes: When the preset conditions are not met, the slope correction coefficient is determined based on the slope compensation deceleration and the planned deceleration. The second product of the slope correction coefficient and the slope compensation deceleration is calculated, and the minimum value between the second product and the deceleration safety margin is taken as the deceleration correction value.

6. The method of claim 5, wherein, Determine the ramp correction factor, including: Add the absolute value of the planned deceleration to the absolute value of the slope compensation deceleration to obtain the first summation term; The ratio of the absolute value of the ramp compensation deceleration to the first summation term is determined as the ramp correction coefficient.

7. The method of claim 3, wherein, The calculation of ramp compensation deceleration includes: Calculate the sine value of the slope angle; The third product of the gravitational acceleration and the sine value is used as the ramp compensation deceleration.

8. The method of claim 2, wherein, The calculation of the adaptive threshold includes: Calculate the fourth product of the vehicle speed and the preset vehicle speed coefficient; Calculate the fifth product of the absolute value of the slope angle and the preset slope coefficient; The adaptive threshold value is determined based on the fourth product, the fifth product, and the preset basic scaling factor.

9. The method of claim 8, wherein, Determining the adaptive threshold value includes: Add the preset constant 1, the fourth product, and the fifth product to obtain the second summation term; The adaptive threshold value is obtained by multiplying the second summation term by the preset basic scaling factor.

10. The method according to any one of claims 1 to 9, characterized in that, The acquisition of vehicle operating status parameters includes: The vehicle's actual acceleration and attitude information are obtained through an inertial measurement unit; The slope angle is obtained based on the actual acceleration and attitude information.

11. The method of claim 10, wherein, Also includes: The wheel speed is obtained by a wheel speed sensor, and the wheel speed is converted into the vehicle speed; The planned deceleration is received by the automatic driving planning module or the longitudinal control module.

12. The method of claim 1, wherein, After determining the target deceleration, the method further includes: The target deceleration is input into a preset first-order low-pass filter for smoothing to obtain the smoothed target deceleration. Generate a total deceleration control command based on the smoothed target deceleration.

13. A controller characterized by comprising: include: processor; The processor is configured to execute the downhill deceleration determination method as described in any one of claims 1 to 12, and to generate a total deceleration control command based on the target deceleration, so as to control the vehicle according to the total deceleration control command.

14. A downgrade section deceleration determination device characterized by comprising: include: A processor, and a memory communicatively connected to the processor; The memory stores computer-executed instructions; The processor executes computer execution instructions stored in the memory to implement the downhill deceleration determination method as described in any one of claims 1 to 12.

15. A computer readable storage medium, characterized in that, The computer-readable storage medium stores computer-executable instructions, which, when executed by a processor, are used to implement the downhill deceleration determination method as described in any one of claims 1 to 12.

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