Vehicle braking control method and device, storage medium and vehicle

Abstract

The invention discloses a vehicle braking control method and device, a storage medium and a vehicle, and relates to the technical field of vehicle control. The method comprises the following steps: acquiring position data and vehicle parameters of a target vehicle during driving; road section information of a target road section is determined based on the position data and preset map data, and the target road section is a downhill road section where the target vehicle is about to drive in the driving direction; according to the vehicle parameters and the road section information, a target gear is obtained through calculation, and the target gear is used for controlling the target vehicle to brake and run at the constant speed in the target road section; and the gearbox gear of the target vehicle is controlled to be adjusted to the target gear. The technical problem that in the prior art, vehicle gearbox gear control lags behind, and the braking strategy accuracy is poor, so that the vehicle running safety is low is solved.

Description

Technical Field

[0001] The present invention relates to the field of vehicle control technology, and in particular to a vehicle braking control method, device, storage medium and vehicle. Background Art

[0002] During vehicle driving, the driver will face various complex road conditions. In the case of engine braking. On the one hand, traditional engine braking requires the driver to manually downshift, and the manual gear shifting operation is cumbersome, and it is difficult for the driver to quickly and accurately determine the required gear, which easily causes the vehicle to downshift in time, resulting in low vehicle driving safety. On the other hand, when the vehicle drives to a section where engine braking is required, the vehicle load and the road section slope are obtained through the on-board sensor. Based on the vehicle load and the road section slope, the braking power required for the vehicle to brake at a constant speed when engine braking is required is calculated, thereby obtaining the gear required for the vehicle to brake at a constant speed. The high dependence on the on-board sensor leads to poor accuracy of the vehicle braking strategy, and the required gear can only be calculated after the vehicle enters the section where engine braking is required. It is easy for the engine speed to be too high, which will cause the engine to have no downshift space, making it difficult for the vehicle to brake at a constant speed, resulting in low vehicle driving safety.

[0003] To address the above-mentioned problems, no effective solution has been proposed yet. Summary of the invention

[0004] The embodiments of the present invention provide a vehicle braking control method, device, storage medium and vehicle to at least solve the technical problem in the related art that the vehicle transmission gear control lag and the poor accuracy of the braking strategy lead to low vehicle driving safety.

[0005] According to one aspect of an embodiment of the present invention, a vehicle braking control method is provided, comprising: obtaining position data and vehicle parameters of a target vehicle during driving; determining section information of a target section based on the position data and preset map data, wherein the target section is a downhill section on which the target vehicle is to travel in the driving direction; calculating a target gear position using the vehicle parameters and the section information, wherein the target gear position is used to control the target vehicle to travel under constant speed braking within the target section; and controlling the gear position of the target vehicle's transmission to be adjusted to the target gear position.

[0006] Optionally, the location data includes at least the current driving location; determining the section information of the target section based on the location data and preset map data includes: determining the target section according to the current driving location, map data and a preset distance threshold; obtaining the section information of the target section from the map data, wherein the section information includes: a target distance between the section starting point of the target section and the current driving location and an average slope of the target section.

[0007] Optionally, determining the target section according to the current driving position, map data and a preset distance threshold includes: determining a range to be searched according to the current driving position and the preset distance threshold; and obtaining the target section from the map data based on the range to be searched, wherein the target section is a downhill section.

[0008] Optionally, calculating the target gear using vehicle parameters and road section information includes: in response to the target distance being less than a first preset threshold, calculating the gearbox ratio of the target vehicle using vehicle parameters and road section information; based on the gearbox ratio, selecting the target gear from a gear ratio mapping table corresponding to the target vehicle.

[0009] Optionally, the vehicle parameters include: preset braking speed, rear axle speed ratio, mechanical transmission efficiency, wheel radius, vehicle mass, engine braking maximum torque and vehicle frontal area, wherein the engine braking maximum torque and preset braking speed are determined by the engine constant speed braking mode set for the target vehicle.

[0010] Optionally, the gearbox ratio of the target vehicle is calculated using vehicle parameters and road section information, including: using the vehicle mass, the vehicle's frontal area, a preset braking speed and the average slope of the road section to calculate the vehicle resistance data; using the engine braking maximum torque, rear axle speed ratio, mechanical transmission efficiency, wheel radius and vehicle resistance data to calculate the gearbox ratio.

[0011] Optionally, the vehicle resistance data includes: rolling resistance, air resistance and slope resistance; the vehicle resistance data is calculated using the vehicle mass, the vehicle's frontal area, a preset braking speed and the average slope of the road section, including: rolling resistance is calculated using the vehicle mass, the rolling resistance coefficient of the target vehicle and the average slope of the road section; air resistance is calculated using the vehicle's frontal area, a preset braking speed, the air resistance coefficient and a second preset threshold; slope resistance is calculated using the vehicle mass and the average slope of the road section.

[0012] Optionally, the vehicle braking control method further includes: acquiring a lowest gear position allowed by a gearbox of the target vehicle; and updating the target gear position to the lowest gear position in response to the target gear position being lower than the lowest gear position.

[0013] According to another aspect of an embodiment of the present invention, a vehicle braking control device is also provided, including: an acquisition module, used to acquire position data and vehicle parameters of a target vehicle during driving; a determination module, used to determine section information of a target section based on the position data and preset map data, wherein the target section is a downhill section on which the target vehicle is to travel in the driving direction; a calculation module, used to calculate a target gear position using the vehicle parameters and section information, wherein the target gear position is used to control the target vehicle to travel under constant speed braking within the target section; and a control module, used to control the gear position of the target vehicle to be adjusted to the target gear position.

[0014] According to another aspect of an embodiment of the present invention, a vehicle is provided, comprising an on-board memory and an on-board processor, wherein a computer program is stored in the on-board memory, and the on-board processor is configured to run the computer program to execute any one of the above-mentioned vehicle braking control methods.

[0015] In an embodiment of the present invention, the position data and vehicle parameters of the target vehicle during driving are obtained; based on the position data and preset map data, the section information of the target section is determined, wherein the target section is a downhill section to be driven by the target vehicle in the driving direction; the target gear is calculated using the vehicle parameters and the section information, wherein the target gear is used to control the target vehicle to drive at a constant speed in the target section; and the gearbox gear of the target vehicle is controlled to be adjusted to the target gear. Thus, the embodiment of the present invention achieves the purpose of using the position data, vehicle parameters and preset map data of the vehicle during driving, so that the vehicle can predictably calculate the appropriate gear before entering the downhill section and control the vehicle to automatically adjust the gear to ensure the driving safety of the vehicle, thereby achieving the technical effect of controlling the vehicle to automatically adjust to the appropriate gear in advance when the vehicle needs to brake to improve the driving safety of the vehicle, thereby solving the technical problem of low driving safety of the vehicle due to the lag in the gearbox control of the vehicle and the poor accuracy of the braking strategy in the related technology. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation of the present invention. In the drawings:

[0017] Figure 1 is a hardware structure block diagram of an optional vehicle terminal for a vehicle braking control method according to an embodiment of the present invention;

[0018] Figure 2 is a flow chart of a vehicle braking control method according to an embodiment of the present invention;

[0019] Figure 3is a schematic diagram of an optional method for calculating the gear position of a vehicle during constant speed braking according to an embodiment of the present invention;

[0020] Figure 4 is a schematic diagram of an optional vehicle downhill braking control process according to an embodiment of the present invention;

[0021] Figure 5 4 is a structural block diagram of a vehicle braking control device according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0023] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0024] According to an embodiment of the present invention, a method embodiment of a vehicle braking control method is provided. It should be noted that the steps shown in the flowchart of the accompanying drawings can be executed in a computer system such as a set of computer executable instructions, and although a logical order is shown in the flowchart, in some cases, the steps shown or described can be executed in an order different from that herein.

[0025] Figure 1 is a hardware structure block diagram of an optional computing terminal for a vehicle braking control method according to an embodiment of the present invention, such as Figure 1As shown, a computing terminal (for example, a computer terminal, a mobile smart terminal, a vehicle terminal, or a cloud computing virtual terminal, etc.) may include: one or more processors 102, a memory 104, and a transmission device 106 configured to implement a communication function, wherein each processor 102 may include but is not limited to a processing component such as a microprocessor (Microcontroller Unit, referred to as MCU) or a programmable logic device (Field Programmable Gate Array, referred to as FPGA).

[0026] The computing terminal may further include: a display device 110, an input / output device 108, a Universal Serial Bus (USB) port (the USB port may be used as one of the ports of a computer bus, not shown in the figure), a network interface (not shown in the figure), a power supply (not shown in the figure) and a camera (not shown in the figure). A person skilled in the art may understand that Figure 1 The structure of the computing terminal shown is only for illustration and does not impose strict limitations on the structure of the computing terminal. Figure 1 More or fewer components as shown, or with Figure 1 Different configurations are shown.

[0027] It should be noted that the one or more processors 102 and / or other data processing circuits may be embodied in whole or in part as software, hardware, firmware or any other combination thereof. In addition, the data processing circuit may be a single independent processing module, or may be integrated in whole or in part into any of the other components in the vehicle terminal (or mobile device).

[0028] The memory 104 may be configured to store software programs and modules of application software, such as the program instructions / data storage device corresponding to the vehicle braking control method in the embodiment of the present invention. The processor 102 executes various functional applications and data processing by running the software programs and modules stored in the memory 104, that is, to implement the above-mentioned vehicle braking control method. The memory 104 may include a high-speed random access memory, and may also include a non-volatile memory, such as one or more magnetic storage devices, flash memory, or other non-volatile solid-state memory. In some examples, the memory 104 may further include a memory remotely arranged relative to the processor 102, and these remote memories may be connected to the vehicle terminal via a network. Examples of the above-mentioned network include, but are not limited to, the Internet, an intranet, a local area network, a mobile communication network, and combinations thereof.

[0029] The transmission device 106 is configured to receive or send data via a network. The specific example of the above network may include a wireless network provided by a communication provider of the vehicle terminal. In one example, the transmission device 106 includes a network adapter (Network Interface Controller, referred to as NIC), which can be connected to other network devices through a base station so as to communicate with the Internet. In one example, the transmission device 106 can be a radio frequency (RF) module, which is configured to communicate with the Internet wirelessly.

[0030] Under the above operating environment, the embodiment of the present invention provides the following Figure 2 The vehicle braking control method shown, Figure 2 is a flow chart of a vehicle braking control method according to an embodiment of the present invention. Figure 2 As shown, the method includes the following steps S201 to S204.

[0031] Step S201, obtaining the position data and vehicle parameters of the target vehicle during driving.

[0032] The target vehicle may be a vehicle with an assisted driving function. The target vehicle may also be a vehicle with an automatic driving function. The location data may be used to indicate the current location of the target vehicle in a high-precision map. The high-precision map may be a high-precision map in the on-board system of the target vehicle. The high-precision map may also be a high-precision map deployed in a cloud system. The vehicle number parameter may be the current status information of the target vehicle, such as the constant speed brake handle status, real-time vehicle speed, real-time gear position, engine water temperature, engine oil temperature, and vehicle load.

[0033] It should be noted that the above-mentioned constant speed brake handle state can be used to indicate whether the constant speed brake mode of the target vehicle is turned on.

[0034] The specific implementation method of obtaining the position data and vehicle parameters of the target vehicle during driving can be: obtaining the position data of the target vehicle during driving in real time through the Global Positioning System (GPS) in the on-board system of the target vehicle, and obtaining the vehicle parameters of the target vehicle during driving in real time through the vehicle controller VCU of the target vehicle.

[0035] It is easy to understand that in the embodiment of the present invention, the real-time acquisition of the position data of the target vehicle during driving can reflect the current position of the target vehicle in the high-precision map in real time, thereby making full use of the high-precision map information, obtaining the information of the driving section ahead in advance, and being able to predictably calculate the gear required for the target vehicle to pass the driving section ahead at a constant speed, thereby improving the stability of the engine. Compared with the solution that only relies on the vehicle load and slope information to calculate the target gear, the engine stability of the above scheme provided by the embodiment of the present invention is higher. In addition, in the embodiment of the present invention, the vehicle parameters of the target vehicle during driving are obtained, not only the vehicle load is considered, but also the current state information of multiple vehicles such as the constant speed brake handle state, vehicle speed, gear, etc. Compared with the solution that only relies on the vehicle load and slope information to calculate the target gear, the target gear calculated by the above scheme provided by the embodiment of the present invention is more targeted and more accurate.

[0036] Step S202, determining the section information of the target section based on the position data and the preset map data, wherein the target section is a downhill section on which the target vehicle is to travel in the travel direction.

[0037] The above-mentioned preset map data can be geographic information data pre-defined in the map, such as: road section name, geographical location of the road section, road section length, road section width, average road section slope, traffic rules to be followed when passing the road section, etc.

[0038] The specific implementation method of determining the section information of the target section based on the location data and the preset map data can be: obtaining the geographic information data pre-defined in the map through a high-precision map, and determining the section information of the target vehicle to be driven in the driving direction according to the location data and the pre-defined geographic information data, thereby determining the section information of the downhill section to be driven in the driving direction of the target vehicle.

[0039] In an exemplary application scenario, when there is a downhill section within n kilometers ahead of the current position of the target vehicle, after obtaining the position data of the target vehicle during driving, combined with the downhill section data pre-defined in the map, the downhill section length and the average slope of the downhill section corresponding to the downhill section within n kilometers ahead of the current position of the target vehicle in the high-precision map are obtained.

[0040] It is easy to understand that in the embodiment of the present invention, by utilizing the position data of the target vehicle during driving and the downhill section data pre-defined in the high-precision map, the downhill section length and the average slope of the downhill section corresponding to the downhill section can be obtained in advance before the target vehicle enters the downhill section. The high-precision map information can be fully utilized, the target gear can be predictably calculated, and the safety of the target vehicle's driving can be improved. Compared with the solution that only relies on vehicle load and slope information to calculate the target gear, the above solution provided by the embodiment of the present invention is safer.

[0041] Step S203, using the vehicle parameters and the road section information, calculate the target gear position, wherein the target gear position is used to control the target vehicle to travel at a constant speed and brake in the target road section.

[0042] The specific implementation method of calculating the target gear position using vehicle parameters and road section information can be: pre-storing a transmission gear ratio mapping table in a storage device of the target vehicle, using vehicle parameters and road section information to calculate the gear information of the target gear that controls the target vehicle to travel at a constant speed by braking in the target road section, finding the corresponding position of the gear information of the target gear in the gear ratio mapping table, and obtaining the target gear position.

[0043] It is easy to understand that in the embodiment of the present invention, by utilizing the current status information and downhill section information of multiple vehicles, the target gear position required for the target vehicle to pass the upcoming driving section at a constant speed can be calculated in advance before the target vehicle enters the downhill section. The target gear position can be calculated in time, thereby avoiding the untimely gear shifting caused by calculating the target gear position after the vehicle enters the downhill section, thereby avoiding the situation where the engine speed of the vehicle is too high during the downhill process and it is difficult to brake at a constant speed, thereby improving the stability of the engine and the safety of vehicle driving.

[0044] Step S204, controlling the gearbox gear of the target vehicle to be adjusted to the target gear.

[0045] The specific implementation method of controlling the target vehicle's transmission gear to be adjusted to the target gear can be: based on the target vehicle's transmission current gear state information and the target gear information, determine whether the transmission current gear is the target gear; if the transmission current gear is not the target gear, automatically adjust the target vehicle's transmission gear to the target gear before the vehicle enters a downhill section.

[0046] It is easy to understand that in the embodiment of the present invention, before the target vehicle enters the downhill section, the target gear required for the target vehicle to pass the front section to be driven at a constant speed is calculated in advance, and the gearbox gear of the target vehicle is adjusted to the target gear. The gear shifting operation can be intervened in advance when the engine speed of the target vehicle is low, thereby avoiding the situation where the engine speed of the vehicle is too high during the downhill process and it is difficult to brake at a constant speed, thereby improving the stability of the engine and the safety of vehicle driving.

[0047] Through the above steps S201 to S204, the position data and vehicle parameters of the target vehicle during driving are obtained; based on the position data and the preset map data, the section information of the target section is determined, wherein the target section is the downhill section to be driven by the target vehicle in the driving direction; the target gear is calculated using the vehicle parameters and the section information, wherein the target gear is used to control the target vehicle to drive at a constant speed in the target section; the gearbox gear of the target vehicle is controlled to be adjusted to the target gear. It can be understood that the scheme provided by the embodiment of the present invention, based on the vehicle controller VCU, the positioning system, and the high-precision map, calculates in advance the target gear required for the target vehicle to pass the forward section to be driven at a constant speed before the target vehicle is about to enter the downhill section, intervenes in advance in the gear shifting when the engine speed is low, and makes full use of the geographic information data in the high-precision map to ensure the stability of the engine operation during the vehicle's driving on the downhill section, thereby improving the safety of vehicle driving. Therefore, the embodiment of the present invention achieves the purpose of utilizing the vehicle's position data, vehicle parameters and preset map data during driving, so that the vehicle can predictably calculate the appropriate gear and control the vehicle to automatically adjust the gear before entering a downhill section, thereby ensuring the safety of vehicle driving. This achieves the technical effect of controlling the vehicle to automatically adjust to the appropriate gear in advance when the vehicle needs to brake to improve the safety of vehicle driving, and further solves the technical problem in the related technology that the vehicle transmission gear control lags and the poor accuracy of the braking strategy lead to low vehicle driving safety.

[0048] The above method of the embodiment of the present invention is further introduced below.

[0049] Optionally, the location data at least includes the current driving location; in the above step S202, determining the section information of the target section based on the location data and preset map data may also include the following execution steps:

[0050] Step S221, determining a target road section according to the current driving position, map data and a preset distance threshold;

[0051] Step S222, obtaining the section information of the target section from the map data, wherein the section information includes: a target distance between the section starting point of the target section and the current driving position and an average section slope of the target section.

[0052] The above-mentioned average slope of the road section can be used to represent the ratio of the height change of the target road section to the horizontal distance change. The average slope of the road section can be obtained by calculating the slope of each of the multiple measuring sections in the target road section and calculating the average value of the slopes of the multiple measuring sections.

[0053] It should be noted that the above-mentioned location data may also include the current road slope and the current road altitude.

[0054] The preset distance threshold may be a distance threshold predefined in a map, and the preset distance threshold is used to represent the farthest distance between the current driving position of the target vehicle and the target road section.

[0055] The target road section is determined based on the current driving position, map data and preset distance threshold. Since the amount of information data contained in all road section information of the road section to be driven by the vehicle in the high-precision map is relatively large, a distance threshold is predefined in the map, and the road section information of the vehicle's current driving position within the preset distance threshold in the map is obtained, and the target road section of the vehicle's current driving position within the preset distance threshold in the map is determined, and then the road section information of the target road section is obtained. This road section information can be regarded as the road section information of the vehicle's current driving position within the preset distance threshold in the map.

[0056] Through the technical solutions provided by the above steps S221 to S222, the embodiments of the present invention consider reducing the data volume of the acquired road section information by setting a preset distance threshold, which can reduce the cost of storing data and improve the efficiency of acquiring the road section information of the target road section.

[0057] Optionally, in the above step S221, determining the target road section according to the current driving position, map data and a preset distance threshold may further include the following execution steps:

[0058] S2211, determining a range to be searched according to the current driving position and a preset distance threshold;

[0059] S2212: Based on the range to be searched, a target road section is searched from the map data, wherein the target road section is a downhill road section.

[0060] The above-mentioned range to be searched may be a range within a preset distance threshold along the direction in which the target vehicle is to travel, starting from the current driving position of the target vehicle.

[0061] In an exemplary application scenario, the preset distance threshold is n kilometers. According to the current driving position of the target vehicle, taking the current driving position of the target vehicle as the starting point, the road section within the range of n kilometers along the direction in which the target vehicle is to travel is searched from the map data to obtain the downhill section.

[0062] Through the technical solution provided by the above steps S2211 to S2212, the embodiment of the present invention determines the target section based on the current driving position, map data and preset distance threshold, and uses the current driving position and preset distance threshold to define a range to be searched. By limiting the search range, it is faster and more accurate to find the downhill section from the map data.

[0063] Optionally, in the above step S203, the target gear position is calculated using the vehicle parameters and the road section information, and the following steps may also be included:

[0064] S231, in response to the target distance being less than a first preset threshold, calculating a gearbox ratio of the target vehicle using vehicle parameters and road section information;

[0065] S232, based on the transmission ratio of the gearbox, selecting a target gear from a gear ratio mapping table corresponding to the target vehicle.

[0066] The first preset threshold value can be used to indicate the minimum value of the target distance when starting to calculate the target gear. The gear ratio of the gearbox can be the proportional relationship between the torque and the rotational speed provided by different internal gear combinations, and the gear ratio can be used to indicate the vehicle power transmission efficiency. The gear ratio mapping table can be used to indicate the relationship between different gears of the gearbox and the engine speed of the vehicle, and the gear speed mapping table can be obtained by testing the engine speed at different gears of the gearbox and performing data statistics on the test results.

[0067] Since it takes a certain amount of calculation time to calculate and select the target gear after the vehicle enters the target road section, it is very likely that the engine speed will be too high and the engine will have no room to downshift. Therefore, in an embodiment of the present invention, when the target distance is less than the first preset threshold, the vehicle parameters and road section information are used to calculate the gearbox transmission ratio of the target vehicle in advance, and the target gear is selected from the gear transmission ratio mapping table corresponding to the target vehicle.

[0068] Through the technical solution provided by the above steps S231 to S232, the embodiment of the present invention sets a first preset threshold value, and determines whether the target distance between the starting point of the target section in the high-precision map and the current driving position is less than the first preset threshold value. It can make full use of the high-precision map information, and pre-calculate the gearbox transmission ratio of the target vehicle before the vehicle enters the target section to obtain the target gear position, so as to control the gear shifting of the target vehicle in time and improve the safety of vehicle driving.

[0069] Optionally, in the above-mentioned vehicle braking control method, the vehicle parameters include: preset braking speed, rear axle speed ratio, mechanical transmission efficiency, wheel radius, vehicle mass, maximum engine braking torque and vehicle frontal area, wherein the braking force data and preset braking speed are determined by the engine constant speed braking mode set for the target vehicle.

[0070] The above-mentioned engine constant speed braking mode may include the following two modes: a constant speed braking function activation mode and a constant speed braking function deactivation mode.

[0071] It should be noted that the above vehicle parameters may also include: constant speed brake handle status, real-time vehicle speed, real-time gear position, engine water temperature, engine oil temperature, and vehicle load.

[0072] Through the technical solution provided above, in the embodiment of the present invention, the target gear is calculated by considering the use of multiple vehicle parameters and road section information, the gear selection is optimized, the engine is ensured to run within the optimal speed range, and the target gear of the vehicle under constant speed braking in the target road section can be calculated more specifically and accurately, and the target gear can be calculated according to the actual road section conditions. For example, the slope of different downhill sections is different, and the corresponding gearbox transmission ratio required for the vehicle to drive at constant speed in different downhill sections is also different. The actual downhill section slope is taken into account in the process of calculating the target gear in the embodiment of the present invention, and the target gear can be calculated more flexibly. Therefore, the embodiment of the present invention can avoid the problem of poor accuracy of the braking strategy when the target gear is calculated based only on the vehicle load and the road section slope in the related art, and can formulate a more targeted, more accurate and more flexible vehicle braking strategy.

[0073] Optionally, in the above step S231, the transmission ratio of the gearbox of the target vehicle is calculated by using the vehicle parameters and the road section information, and the following steps may also be included:

[0074] S2311, using the vehicle mass, the vehicle frontal area, the preset braking speed and the average slope of the road section, calculate the vehicle resistance data;

[0075] S2312, calculates the gearbox ratio using the engine brake maximum torque, rear axle speed ratio, mechanical transmission efficiency, wheel radius and vehicle resistance data.

[0076] The preset braking speed can be used to indicate the speed at which the vehicle can travel downhill at a constant speed after braking. The vehicle resistance data can be a variety of resistance data that affect the vehicle's constant speed braking.

[0077] In order to more accurately calculate the gearbox ratio corresponding to the vehicle's constant speed braking on the target road section, and further consider the impact of environmental factors on the vehicle's constant speed braking, the vehicle resistance data is calculated using the vehicle mass, vehicle frontal area, preset braking speed and average road section slope. Furthermore, the gearbox ratio is calculated using the engine braking maximum torque, rear axle speed ratio, mechanical transmission efficiency, wheel radius and vehicle resistance data.

[0078] Through the technical solutions provided by the above steps S2311 to S2312, the embodiment of the present invention calculates the vehicle resistance data affecting the vehicle's constant speed braking driving by using the vehicle mass, the vehicle's frontal area, the preset braking speed and the average slope of the road section, and more comprehensively considers the factors affecting the vehicle's constant speed braking driving. Therefore, the embodiment of the present invention can more accurately calculate the gearbox transmission ratio.

[0079] Optionally, the vehicle resistance data includes rolling resistance, air resistance and slope resistance; in the above step S2311, the vehicle resistance data is calculated using the vehicle mass, the vehicle frontal area, the preset braking speed and the average slope of the road section, and the following steps may also be included:

[0080] S23111, calculate the rolling resistance using the vehicle mass, the rolling resistance coefficient of the target vehicle and the average slope of the road section;

[0081] S23112, calculating air resistance using the frontal area of ​​the vehicle, a preset braking speed, an air resistance coefficient, and a second preset threshold;

[0082] S23113, using the vehicle mass and the average slope of the road section, calculate the slope resistance.

[0083] The rolling resistance may be used to represent the resistance encountered by the wheels during rolling. The second preset threshold may be a fixed value set in advance. The air resistance may be used to represent the resistance generated by the interaction between the shape of the vehicle and the air flow. The slope resistance may be used to represent the resistance generated by the inclination angle of the slope when the vehicle moves on a ramp.

[0084] In order to calculate the vehicle resistance data more accurately, the rolling resistance is calculated using the vehicle mass, the rolling resistance coefficient of the target vehicle and the average slope of the road section. The air resistance is calculated using the vehicle's frontal area, the preset braking speed, the air resistance coefficient and the second preset threshold. The slope resistance is calculated using the vehicle mass and the average slope of the road section.

[0085] Through the technical solutions provided by the above steps S23111 to S23113, the embodiment of the present invention can more accurately predict the movement of the vehicle in the target section and optimize the braking control strategy of the target vehicle by calculating the various vehicle resistances during the constant speed braking process of the vehicle, so that the above solution of the embodiment of the present invention can more accurately calculate the vehicle resistance data.

[0086] Optionally, the vehicle braking control method may further include the following method steps:

[0087] S2001, obtaining the lowest gear position allowed by the gearbox of the target vehicle;

[0088] S2002: In response to the target gear being lower than the lowest gear, updating the target gear to the lowest gear.

[0089] Since the target gear is lower than the lowest gear of the target vehicle, it is easy to cause a transmission system failure and make it difficult to control the vehicle engine, and the formulated vehicle braking strategy is less safe. Therefore, in the embodiment of the present invention, the lowest gear allowed by the gearbox of the target vehicle is obtained, and further, in response to the target gear being lower than the lowest gear, the target gear is updated to the lowest gear.

[0090] Through the technical solution provided by the above steps S2001 to S2002, the embodiment of the present invention obtains the lowest gear allowed by the gearbox of the target vehicle, and when the target gear is lower than the lowest gear, sets the target gear to the lowest gear, thereby protecting the vehicle's transmission system and preventing damage to mechanical components. The above solution of the embodiment of the present invention can improve the safety of the vehicle's constant speed braking strategy.

[0091] The above vehicle braking control method can be applied to the scene of vehicle assisted driving. Taking the scene of constant speed braking of the vehicle as an example, a method is provided. Figure 3 The schematic diagram of the gear position calculation method process for a vehicle with constant speed braking is shown in FIG. Figure 3 As shown, in the scene of constant speed braking of the vehicle, the vehicle controller of the vehicle with assisted driving function obtains the vehicle information such as constant speed braking handle signal, vehicle speed, brake pedal opening, gear position, engine water temperature, engine oil temperature and road information such as road slope, road altitude and current driving position through the vehicle communication system. The vehicle communication system includes but is not limited to the controller area network (Controller Area Network, referred to as CAN) bus, local interconnect network (Local Interconnect Network, referred to as LIN) bus and hard line sensor, etc. The constant speed braking handle signal is used to determine whether the constant speed braking mode of the vehicle is turned on. When the constant speed braking mode of the vehicle is turned on, the engine braking torque required for the constant speed braking of the vehicle is calculated by the torque calculation module in the vehicle controller based on the road information and vehicle information. Further, based on the braking torque, the gear calculation module in the vehicle controller calculates the gear position of the gearbox required for the constant speed braking of the vehicle, and the gear position torque control module in the vehicle controller sets the gear position of the constant speed braking of the vehicle to the target gear position. Therefore, the embodiment of the present invention accurately calculates the target gear required for constant speed braking of the vehicle in the scenario of constant speed braking of the vehicle based on various vehicle information and the road slope of the downhill section, thereby improving the stability of the vehicle engine and enhancing the safety of vehicle driving in the scenario of constant speed braking of the vehicle.

[0092] The above vehicle braking control method can be applied to a scene where the vehicle engine braking is required. Taking the scene of a downhill section as an example, a method is provided as follows: Figure 4 The schematic diagram of the vehicle downhill braking control process is shown in FIG. Figure 4As shown in the figure, in the downhill section scenario, after the target vehicle positioning system successfully locates, when there is a downhill section within n kilometers ahead of the current driving position of the target vehicle, the distance S between the starting point of the downhill section and the current driving position is obtained. rest and the average slope of the downhill section i down , when S rest When S is less than a first preset threshold, the gear calculation module starts to calculate the target gear. The first preset threshold can be set to a fixed value of 20m. rest When the vehicle resistance data is less than 20m, the vehicle resistance data may include: rolling resistance F f , air resistance F w , Slope resistance F i Using braking force data, rear axle ratio, mechanical transmission efficiency, wheel radius, rolling resistance F f , air resistance F w and slope resistance F i , calculate the gearbox transmission ratio, select the target gear from the gear ratio mapping table corresponding to the target vehicle based on the gearbox transmission ratio, and determine whether the target gear is lower than the lowest gear. When the target gear is lower than the lowest gear, set the constant speed downhill gear to the lowest gear; when the target gear is not lower than the lowest gear, set the constant speed downhill gear to the target gear.

[0093] The above-mentioned constant speed downhill gear position can be used to represent the actual gear position of the target vehicle when traveling in the target road section.

[0094] The above rolling resistance F f It can be calculated by the following formula (1).

[0095] F f =mgfcosα Formula (1)

[0096] In the above formula (1), m represents the mass of the vehicle, g represents the acceleration due to gravity, f represents the rolling resistance coefficient, and α represents the average slope of the road section.

[0097] The above air resistance F w It can be calculated by the following formula (2).

[0098]

[0099] In the above formula (2), C d represents the air resistance coefficient, A represents the windward area, V set Indicates the set vehicle speed for constant downhill driving.

[0100] The above slope resistance F i It can be calculated by the following formula (3).

[0101] F i= mgi down Formula (3)

[0102] In the above formula (3), m represents the mass of the vehicle, and g represents the acceleration due to gravity.

[0103] When the vehicle is in a constant speed braking state, the vehicle has no driving force. At this time, the vehicle needs wheel end engine braking force F when it is going downhill at a constant speed. Ebrk and rolling resistance F f , air resistance F w , Slope resistance F i The sum of the three resistances reaches equilibrium, and the equivalent dynamic equation is expressed as the following equation (4).

[0104] F Ebrk =F f ++F w +F i Formula (4)

[0105] The wheel end engine braking force F Ebrk It can be calculated by the following formula (5):

[0106]

[0107] In the above formula (5), T Ebrk Indicates the maximum braking force of the engine brake, i g represents the transmission ratio of the gearbox, i0 represents the rear axle speed ratio, η t represents the mechanical transmission efficiency, and r represents the tire radius.

[0108] By using the above equations (4) and (5), the following equation (6) can be obtained.

[0109]

[0110] From this, we can get the formula (7) for calculating the gearbox transmission ratio required for constant speed downhill driving:

[0111]

[0112] It should be noted that the constant speed downhill gear is set as the current gear of the target vehicle when at least one of the following conditions exists: the positioning system of the target vehicle is not positioned, the distance S between the starting point of the downhill section and the current driving position is rest Not less than 20m, and the driver's constant speed brake handle switch is not turned on.

[0113] Therefore, on the one hand, the embodiment of the present invention accurately calculates the various resistances that affect the constant speed braking of the vehicle in the downhill section by utilizing the vehicle parameters and the average slope of the downhill section, accurately calculates the transmission ratio of the gearbox, and selects a more accurate target gear, thereby improving the accuracy of the vehicle constant speed braking strategy formulated in the downhill section scenario, thereby improving the safety of vehicle driving in the downhill section scenario; on the other hand, the embodiment of the present invention considers the feasibility of the calculated target gear by judging whether the target gear is lower than the lowest gear allowed by the gearbox of the target vehicle, thereby being able to protect the vehicle's transmission system and improving the safety of vehicle driving in the downhill section scenario.

[0114] According to an embodiment of the present invention, a device embodiment of a vehicle brake control device is also provided, and the vehicle brake control device is configured to implement the above method embodiment and multiple optional implementations of the method embodiment, and the technical content described above is not repeated in the device embodiment. It should be noted that in the following related descriptions of the device embodiment, a "module" can be configured to be software, hardware, or a combination of software and hardware that implements a specified function.

[0115] Figure 5 is a structural block diagram of a vehicle brake control device according to an embodiment of the present invention. Figure 5 As shown, the device comprises:

[0116] The acquisition module 501 is used to acquire the position data and vehicle parameters of the target vehicle during driving;

[0117] A determination module 502, configured to determine the section information of a target section based on the position data and preset map data, wherein the target section is a downhill section on which the target vehicle is to travel in the travel direction;

[0118] The calculation module 503 is used to calculate the target gear position by using the vehicle parameters and the road section information, wherein the target gear position is used to control the target vehicle to travel at a constant speed and brake in the target road section;

[0119] The control module 504 is used to control the gearbox gear of the target vehicle to be adjusted to the target gear.

[0120] Optionally, in the above-mentioned vehicle braking control device, the position data at least includes the current driving position.

[0121] Optionally, the above-mentioned determination module 502 is also used to: determine the target section based on the current driving position, map data and a preset distance threshold; obtain section information of the target section from the map data, wherein the section information includes: the target distance between the starting point of the target section and the current driving position and the average slope of the target section.

[0122] Optionally, the determination module 502 is further used to: determine a range to be searched according to a current driving position and a preset distance threshold; and search for a target road section from map data based on the range to be searched, wherein the target road section is a downhill road section.

[0123] Optionally, the above-mentioned calculation module 503 is also used to: in response to the target distance being less than a first preset threshold, calculate the gearbox ratio of the target vehicle using vehicle parameters and road section information; based on the gearbox ratio, select the target gear from the gear speed mapping table corresponding to the target vehicle.

[0124] Optionally, in the above-mentioned vehicle braking control device, the vehicle parameters include: braking force data, preset braking speed, rear axle speed ratio, mechanical transmission efficiency, wheel radius, vehicle mass, engine braking maximum torque and vehicle frontal area, wherein the engine braking maximum torque and preset braking speed are determined by the engine constant speed braking mode set for the target vehicle.

[0125] Optionally, the above-mentioned calculation module 503 is also used to: calculate the vehicle resistance data using the vehicle mass, the vehicle's frontal area, the preset braking speed and the average slope of the road section; calculate the gearbox transmission ratio using the engine braking maximum torque, the rear axle speed ratio, the mechanical transmission efficiency, the wheel radius and the vehicle resistance data.

[0126] Optionally, in the above-mentioned vehicle braking control device, the vehicle resistance data includes: rolling resistance, air resistance and slope resistance.

[0127] Optionally, the above-mentioned calculation module 503 is also used to: calculate the rolling resistance using the vehicle mass, the rolling resistance coefficient of the target vehicle and the average slope of the road section; calculate the air resistance using the vehicle's frontal area, a preset braking speed, the air resistance coefficient and a second preset threshold; calculate the slope resistance using the vehicle mass and the average slope of the road section.

[0128] Optionally, in addition to all the above modules, the vehicle braking control device also includes an update module 505 (not shown in the figure), which is used to: obtain the lowest gear allowed by the gearbox of the target vehicle; in response to the target gear being lower than the lowest gear, update the target gear to the lowest gear.

[0129] It should be noted that the above modules can be implemented by software or hardware. For the latter, it can be implemented in the following ways, but not limited to: the above modules are all located in the same processor; or the above modules are located in different processors in any combination.

[0130] Through the device technical solutions corresponding to the above-mentioned acquisition module, determination module, calculation module, and control module, the embodiment of the present invention obtains the position data and vehicle parameters of the target vehicle during driving through the acquisition module; determines the section information of the target section based on the position data and preset map data through the determination module, wherein the target section is a downhill section to be driven by the target vehicle in the driving direction; calculates the target gear position by using the vehicle parameters and the section information through the calculation module, wherein the target gear position is used to control the target vehicle to drive at a constant speed and brake in the target section; and controls the gear position of the gearbox of the target vehicle to be adjusted to the target gear position through the control module.

[0131] In the above-mentioned vehicle braking control device provided by the embodiment of the present invention, the position data and vehicle parameters of the target vehicle during driving are obtained; based on the position data and the preset map data, the section information of the target section is determined, wherein the target section is the downhill section to be driven by the target vehicle in the driving direction; the target gear is calculated by using the vehicle parameters and the section information, wherein the target gear is used to control the target vehicle to brake at a constant speed in the target section; and the gearbox gear of the target vehicle is controlled to be adjusted to the target gear. Thus, the embodiment of the present invention achieves the purpose of using the position data, vehicle parameters and preset map data of the vehicle during driving, so that the vehicle can predictably calculate the appropriate gear before entering the downhill section and control the vehicle to automatically adjust the gear to ensure the driving safety of the vehicle, thereby achieving the technical effect of controlling the vehicle to automatically adjust to the appropriate gear in advance when the vehicle needs to brake to improve the driving safety of the vehicle, thereby solving the technical problem of low driving safety of the vehicle due to the lag in the gear control of the vehicle gearbox and the poor accuracy of the braking strategy in the related technology.

[0132] According to another aspect of an embodiment of the present invention, a vehicle is provided, comprising an on-board memory and an on-board processor, wherein a computer program is stored in the on-board memory, and the on-board processor is configured to run the computer program to execute any one of the aforementioned vehicle braking control methods.

[0133] Optionally, in this embodiment, the above-mentioned on-board processor can be configured to perform the following steps through a computer program: obtain the position data and vehicle parameters of the target vehicle during driving; determine the section information of the target section based on the position data and preset map data, wherein the target section is a downhill section where the target vehicle is to travel in the driving direction; calculate the target gear position using the vehicle parameters and section information, wherein the target gear position is used to control the target vehicle to travel under constant speed braking in the target section; control the gear position of the target vehicle to be adjusted to the target gear position.

[0134] Optionally, the specific examples in this embodiment may refer to the examples described in the above embodiment and its optional implementation manners, which will not be described in detail here.

[0135] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0136] In the several embodiments provided by the present invention, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0137] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0138] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0139] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product. The computer software product is stored in a storage medium, including several instructions for a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: various media that can store program codes, such as USB flash drives, ROM, RAM, mobile hard disks, magnetic disks or optical disks.

[0140] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A vehicle braking control method, characterized in that: include: Obtaining the location data and vehicle parameters of the target vehicle while driving; Determining the section information of the target section based on the position data and the preset map data, wherein the target section is a downhill section on which the target vehicle is to travel in the travel direction; Calculating a target gear position using the vehicle parameters and the road section information, wherein the target gear position is used to control the target vehicle to travel at a constant speed and brake within the target road section; The gearbox gear of the target vehicle is controlled to be adjusted to the target gear.

2. The vehicle braking control method according to claim 1, characterized in that: The position data at least includes the current driving position; Determining the section information of the target section based on the location data and the preset map data includes: Determining the target road section according to the current driving position, the map data and a preset distance threshold; The section information of the target section is acquired from the map data, wherein the section information includes: a target distance between a section start point of the target section and the current driving position and an average section slope of the target section.

3. The vehicle braking control method according to claim 2, characterized in that: Determining the target road section according to the current driving position, the map data and a preset distance threshold comprises: Determine a range to be searched according to the current driving position and the preset distance threshold; Based on the range to be searched, the target road section is searched from the map data, wherein the target road section is a downhill road section.

4. The vehicle braking control method according to claim 2, characterized in that: Calculating the target gear position using the vehicle parameters and the road section information includes: In response to the target distance being less than a first preset threshold, calculating a gearbox ratio of the target vehicle using the vehicle parameters and the road section information; Based on the gearbox transmission ratio, the target gear is selected from a gear transmission ratio mapping table corresponding to the target vehicle.

5. The vehicle braking control method according to claim 4, characterized in that: The vehicle parameters include: preset braking speed, rear axle speed ratio, mechanical transmission efficiency, wheel radius, vehicle mass, engine braking maximum torque and vehicle frontal area, wherein the engine braking maximum torque and preset braking speed are determined by the engine constant speed braking mode set for the target vehicle.

6. The vehicle braking control method according to claim 5, characterized in that: Calculating the gearbox ratio of the target vehicle using the vehicle parameters and the road section information includes: The vehicle resistance data is calculated using the vehicle mass, the vehicle frontal area, the preset braking speed and the average slope of the road section; The gearbox transmission ratio is calculated using the engine brake maximum torque, the rear axle speed ratio, the mechanical transmission efficiency, the wheel radius and the vehicle resistance data.

7. The vehicle braking control method according to claim 6, characterized in that: The vehicle resistance data includes rolling resistance, air resistance and slope resistance; the vehicle resistance data calculated by using the vehicle mass, the vehicle frontal area, the preset braking speed and the average slope of the road section includes: The rolling resistance is calculated using the vehicle mass, the rolling resistance coefficient of the target vehicle and the average slope of the road section; The air resistance is calculated using the frontal area of ​​the vehicle, the preset braking speed, the air resistance coefficient and the second preset threshold; The slope resistance is calculated using the vehicle mass and the average slope of the road section.

8. The vehicle braking control method according to claim 1, characterized in that: The method further comprises: Obtaining the lowest gear position allowed by the gearbox of the target vehicle; In response to the target gear being lower than the lowest gear, the target gear is updated to the lowest gear.

9. A vehicle brake control device, characterized in that: include: An acquisition module is used to acquire the position data and vehicle parameters of the target vehicle during driving; A determination module, configured to determine the section information of a target section based on the position data and preset map data, wherein the target section is a downhill section on which the target vehicle is to travel in a travel direction; A calculation module, used to calculate a target gear position by using the vehicle parameters and the road section information, wherein the target gear position is used to control the target vehicle to travel at a constant speed and brake within the target road section; A control module is used to control the gearbox gear of the target vehicle to be adjusted to the target gear.

10. A vehicle, characterized in that: The vehicle brake control method comprises an on-board memory and an on-board processor, wherein the on-board memory stores a computer program, and the on-board processor is configured to run the computer program to execute the vehicle brake control method according to any one of claims 1 to 8.

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