Method, device and equipment for determining braking deceleration and storage medium

Abstract

The invention relates to a method for determining braking deceleration, which comprises the following steps of: acquiring a pedal travel generated by stepping an electronic brake pedal in an electronic mechanical braking system by a driver in a vehicle braking process; first wheel end braking force provided by brake assembly caliper clamping force of wheels of the vehicle is determined based on the pedal stroke by means of preset braking system braking parameters, and first wheel end braking force provided by brake assembly caliper clamping force of the wheels of the vehicle is recovered based on the pedal stroke by means of preset driving motor energy recovery parameters. Second wheel end braking force provided by torque generated by energy recovery of a driving motor of wheels of the vehicle is determined; determining the total braking force of front wheels based on the first wheel end braking force and the second wheel end braking force corresponding to the front wheels of the vehicle; and when the vehicle is under the function action of the electronic braking force distribution system, first rear wheel total braking force is determined based on the front wheel total braking force, and the braking deceleration of the vehicle is determined based on the front wheel total braking force and the first rear wheel total braking force. Therefore, the braking accuracy can be improved.

Description

Technical Field

[0001] This application relates to the field of vehicle braking technology, and in particular to a method, apparatus, device, and storage medium for determining braking deceleration. Background Technology

[0002] The braking system is a crucial component for ensuring safe vehicle operation. Its primary function is to generate braking force under the driver's control to achieve deceleration or stopping. With the development of new energy vehicles and intelligent driving technologies, traditional hydraulic or pneumatic braking systems have gradually revealed their shortcomings in terms of structural complexity, response speed, and control precision. They are also unable to meet the high requirements of Level 3 and above autonomous driving systems in terms of fail-safe braking.

[0003] Due to the differences in the functional structure and working principle of electromechanical braking systems, the methods for determining the intelligent deceleration of the original hydraulic and pneumatic braking systems are no longer applicable to current electromechanical braking systems. Further research and development are needed for the braking technology of electromechanical braking systems. Summary of the Invention

[0004] This application provides a method, apparatus, device, and storage medium for determining braking deceleration.

[0005] In a first aspect, embodiments of this application provide a method for determining braking deceleration, the method comprising:

[0006] Acquire the pedal travel generated by the driver's depressing of the electronic brake pedal in the electromechanical braking system during vehicle braking;

[0007] Using preset braking system parameters and based on pedal travel, the first wheel-end braking force provided by the caliper clamping force of the vehicle's wheel brake assembly is determined, and using preset drive motor energy recovery parameters and based on pedal travel, the second wheel-end braking force provided by the torque generated by the drive motor energy recovery of the vehicle's wheel is determined.

[0008] The total braking force of the front wheels is determined based on the braking force at the first wheel end and the braking force at the second wheel end corresponding to the front wheels of the vehicle.

[0009] When the vehicle is in the electronic brake force distribution system, the total braking force of the first rear wheel is determined based on the total braking force of the front wheels, and the braking deceleration of the vehicle is determined based on the total braking force of the front wheels and the total braking force of the first rear wheel.

[0010] Based on the aforementioned technical methods, the braking force at the first and second wheel ends of each wheel is calculated by firstly using any possible pedal travel of the electronic brake pedal, combined with preset braking system parameters and drive motor energy recovery parameters. Then, the braking forces of all wheels are combined to obtain the overall braking deceleration of the vehicle. In this way, on the one hand, the logical relationship between the electronic brake pedal travel and braking parameters enables precise modeling of the braking force of each wheel, which helps improve the accuracy of theoretical calculations and analysis. On the other hand, by simultaneously considering both traditional braking and energy recovery as braking force sources, the actual front wheel braking performance of the vehicle can be more comprehensively reflected. Therefore, under the function of the electronic brake force distribution system, the total rear wheel braking force determined based on the actual total front wheel braking force can effectively ensure the relationship between the front and rear wheels, avoiding tail-swing events caused by rear wheel lock-up, thereby improving the accuracy of braking deceleration.

[0011] Furthermore, based on the total braking force of the front wheels, the total braking force of the first rear wheels is determined, including: based on the total braking force of the front wheels, the braking stiffness of the front wheels is determined, and the braking stiffness of the front wheels is determined as the braking stiffness of the rear wheels; based on the braking stiffness of the rear wheels, the total braking force of the first rear wheels is determined.

[0012] Based on the above technical means, under the function of the electronic brake force distribution system, the front wheel braking stiffness determined based on the actual total braking force of the front wheels is more accurate than the theoretical simulation itself. Furthermore, the front wheel braking stiffness is directly used as the rear wheel braking stiffness to determine the first total braking force of the rear wheels of the vehicle, so that the front and rear wheels brake in a consistent manner, which can make the front and rear wheels lock up at the same time, thereby avoiding the fishtailing phenomenon caused by the rear wheels locking up first.

[0013] Furthermore, based on the total braking force of the front wheels, the front wheel braking stiffness is determined, including: determining a first parameter based on the vehicle's weight, center of gravity distance from the rear axle, and front and rear wheel track; determining a second parameter based on the vehicle's weight, center of gravity height, and front and rear wheel track; determining a third parameter based on the vehicle's weight, total front wheel braking force, and front and rear wheel track; and determining the front wheel braking stiffness based on the first, second, and third parameters.

[0014] Based on the aforementioned technical means, the front wheel braking stiffness is calculated based on the characteristics of the vehicle itself. However, the coefficient related to the friction between the tire and the ground is not taken into account. Furthermore, the coefficient related to the friction between the tire and the ground is relatively small. If the coefficient related to the friction between the tire and the ground is used to determine the total braking force of the front wheels, slippage is likely to occur. On the other hand, determining the total braking force of the front wheels with a smaller front wheel braking stiffness can effectively reduce the slippage rate.

[0015] Furthermore, based on the rear wheel braking stiffness, the total braking force of the first rear wheel is determined, including: determining the sixth parameter based on the vehicle's weight, center of gravity distance from the front axle, front wheel braking stiffness, and front and rear wheel track; determining the seventh parameter based on the ratio of the vehicle's weight, center of gravity height, rear wheel braking stiffness, and front and rear wheel track; and determining the total braking force of the first rear wheel based on the sixth and seventh parameters.

[0016] Based on the above technical means, in this embodiment of the application, the front wheel braking stiffness is directly determined as the rear wheel braking stiffness, and then the total braking force of the first rear wheel is determined based on the rear wheel braking stiffness, which ensures that the front and rear wheel braking stiffness are consistent and the braking pace is consistent, and can effectively prevent the rear wheels from locking up first.

[0017] Furthermore, the method also includes: when the vehicle is in the function of the anti-lock braking system, determining the total braking force of the second rear wheel based on the braking force at the first wheel end and the braking force at the second wheel end corresponding to the rear wheel of the vehicle; and determining the braking deceleration of the vehicle based on the total braking force of the front wheel and the total braking force of the second rear wheel.

[0018] Based on the aforementioned technical means, when the vehicle is under the function of the anti-lock braking system, the braking deceleration of the vehicle can be determined based on the second total braking force of the rear wheels, which is determined by the actual total braking force of the front wheels and the actual total braking force of the rear wheels, thus ensuring the controllability of the vehicle.

[0019] Furthermore, the preset braking system parameters include the braking coefficients corresponding to the vehicle's wheels; using the preset braking system parameters, based on the pedal travel, the first wheel-end braking force provided by the brake assembly caliper clamping force of the vehicle's wheels is determined, including: for the vehicle's wheels, determining the product of the braking coefficient corresponding to the wheel and the pedal travel as the clamping force of the brake assembly caliper corresponding to the wheel; for the vehicle's wheels, determining the first wheel-end braking force corresponding to the wheel based on the clamping force of the brake assembly caliper corresponding to the wheel and the corresponding wheel rotation ratio.

[0020] Based on the aforementioned technical methods, the braking coefficient corresponding to each wheel is introduced and multiplied by the pedal travel to obtain the caliper clamping force of that wheel. This is then combined with the wheel rotation ratio to calculate the braking force at the first wheel end. In this way, on the one hand, the differences in braking response between different wheels are taken into account, allowing for better matching of the braking requirements under actual vehicle operating conditions; on the other hand, by incorporating the physical characteristics of the wheel rotation ratio, the calculation of the braking force at the first wheel end is ensured to be more consistent with mechanical principles, thereby improving the accuracy of braking deceleration prediction.

[0021] Furthermore, the wheel rotation ratio includes the speed conversion factor and the wheel rolling radius corresponding to the wheel; based on the caliper clamping force of the brake assembly corresponding to the wheel and the corresponding wheel rotation ratio, the first wheel-end braking force corresponding to the wheel is determined, including: determining the actual caliper clamping force corresponding to the wheel as the product of the caliper clamping force of the brake assembly corresponding to the wheel and the corresponding brake braking efficiency; determining the wheel rotation ratio corresponding to the wheel as the ratio of the speed conversion factor to the corresponding wheel rolling radius; and determining the first wheel-end braking force corresponding to the wheel as the product of the wheel rotation ratio and the corresponding actual caliper clamping force.

[0022] Based on the aforementioned technical methods, a more refined braking model was constructed by introducing two key variables: brake efficiency and wheel rotation ratio. This approach, on the one hand, considers the impact of brake efficiency on the actual clamping force, improving physical realism and reliability; on the other hand, by defining the wheel rotation ratio through the ratio of the speed conversion factor to the rolling radius, the calculation of the braking force at the first wheel end more closely reflects actual kinematic characteristics, thereby enhancing the rationality and consistency of the braking deceleration calculation results.

[0023] Furthermore, the preset drive motor energy recovery parameters include the energy recovery braking coefficient corresponding to the vehicle's wheels; using the preset drive motor energy recovery parameters, based on the pedal travel, the second wheel-end braking force provided by the torque generated by the drive motor energy recovery of the vehicle's wheels is determined, including: for the vehicle's wheels, determining the torque generated by the drive motor energy recovery of the wheel based on the product of the wheel's energy recovery braking coefficient and the pedal travel; for the vehicle's wheels, determining the second wheel-end braking force corresponding to the wheel as the ratio of the wheel's torque to the corresponding wheel rolling radius.

[0024] Based on the aforementioned technical means, by introducing an energy recovery braking coefficient and combining it with pedal travel, the energy recovery torque of each wheel is calculated, and then further converted into the braking force at the second wheel end. In this way, based on preset drive motor energy recovery parameters and pedal travel, the energy recovery intensity can be adjusted, improving the driving experience. Furthermore, by normalizing the torque through the wheel rolling radius, the expression of the braking force at the second wheel end is consistent with that at the first wheel end, facilitating subsequent summation calculations and thus improving the coordination and consistency of the entire braking deceleration calculation process.

[0025] Furthermore, the method also includes: establishing a first logical relationship between pedal travel and braking force at the first wheel end based on the initial braking system braking parameters, and establishing a second logical relationship between pedal travel and braking force at the second wheel end based on the initial drive motor energy recovery parameters; establishing a third logical relationship between pedal travel and vehicle braking deceleration based on the first and second logical relationships; simulating vehicle braking based on the third logical relationship for different braking scenarios to obtain the simulation curve of the first relationship corresponding to the third logical relationship; and adjusting the initial braking system braking parameters and the initial drive motor energy recovery parameters based on the simulation curve of the first relationship to obtain the preset braking system braking parameters and the preset drive motor energy recovery parameters.

[0026] Based on the aforementioned technical methods, a multi-level logical relationship is constructed between pedal travel, braking force of each wheel, and vehicle braking deceleration. Simulation tools are then used to verify the performance of these relationships under different braking scenarios, thereby achieving adaptive parameter optimization. This approach allows for the identification of potential braking performance issues during the design phase, reducing real-vehicle testing costs. Furthermore, continuous parameter adjustments based on simulation feedback ensure that the braking system maintains stable and reliable performance under various complex operating conditions, thus improving product development efficiency and quality.

[0027] Furthermore, the method also includes: establishing a fourth logical relationship between pedal force and pedal travel based on the initial elastic coefficient of the electronic brake pedal; establishing a fifth logical relationship between pedal force and braking deceleration based on the fourth logical relationship; simulating vehicle braking based on the fifth logical relationship for different braking scenarios to obtain a second relationship simulation curve corresponding to the fifth logical relationship; adjusting the initial braking parameters based on the second relationship simulation curve to obtain preset braking parameters; wherein the initial braking parameters include at least one of the following: initial braking system braking parameters, initial drive motor energy recovery parameters, and initial elastic coefficient.

[0028] Based on the aforementioned technical methods, by introducing the logical relationship between pedal force and pedal travel, and further extending it to the relationship between pedal force and braking deceleration, the braking performance evaluation becomes more comprehensive. In this way, simulation analysis of the vehicle's braking response under different pedal force inputs can help optimize pedal feel design and improve the driver's operating experience.

[0029] Furthermore, after establishing the logical relationship between pedal force and pedal travel, the method also includes: simulating vehicle braking based on the sixth logical relationship between pedal force and pedal travel to obtain the third relationship simulation curve corresponding to the sixth logical relationship; and adjusting the initial elastic coefficient based on the third relationship simulation curve to obtain the preset elastic coefficient.

[0030] Based on the aforementioned technical methods, by introducing a relationship model between pedal force and pedal travel and conducting simulation analysis, the design of the pedal simulator becomes more scientific and reasonable. This effectively improves the smoothness of pedal force changes with travel, avoiding abrupt force changes during driving and enhancing driving comfort. Furthermore, by adjusting the elastic coefficient, the pedal simulator can better match the dynamic characteristics of the vehicle's braking system, thereby improving the consistency and stability of overall braking performance.

[0031] Furthermore, the initial drive motor energy recovery parameters include the initial axle energy recovery coefficient; the method also includes: establishing a seventh logical relationship between the pedal travel and the torque generated by the axle drive motor energy recovery based on the axle energy recovery coefficient; the axle is the front axle or rear axle of the vehicle; simulating the vehicle's braking based on the seventh logical relationship to obtain the fourth relationship simulation curve corresponding to the seventh logical relationship; and adjusting the initial axle energy recovery coefficient based on the fourth relationship simulation curve to obtain the preset drive motor energy recovery parameters.

[0032] Based on the aforementioned technical methods, by separately modeling the energy recovery system for the front or rear axle and combining it with pedal travel simulation analysis, the energy recovery strategy becomes more flexible and controllable. This allows for optimization of the energy recovery path for vehicles with different drive layouts, improving energy utilization during braking; furthermore, by continuously adjusting the energy recovery coefficient through simulation feedback, the system can improve the overall vehicle's energy efficiency and range while ensuring braking performance.

[0033] Furthermore, the method also includes: establishing an eighth logical relationship between the front wheel braking stiffness and the total front wheel braking force; establishing a ninth logical relationship between the clamping force of the caliper assembly corresponding to the front wheel of the vehicle and the braking force at the first wheel end based on preset braking system braking parameters; establishing a tenth logical relationship between the front wheel braking stiffness and the clamping force of the caliper assembly corresponding to the front wheel of the vehicle based on the eighth and ninth logical relationships; simulating the vehicle's braking based on the tenth logical relationship to obtain the fifth relationship simulation curve corresponding to the tenth logical relationship, and determining the caliper specifications corresponding to the front wheel based on the fifth relationship simulation curve.

[0034] Based on the aforementioned technical methods, by introducing a relationship model between front wheel braking stiffness and caliper clamping force, and combining it with simulation analysis, the selection of front wheel calipers can be made more precise. This ensures, on the one hand, that the front wheels can provide sufficient braking force under different braking conditions, avoiding brake failure or excessive wear caused by inappropriate caliper specifications; on the other hand, by continuously optimizing caliper selection through simulation feedback, the braking system can minimize hardware costs while meeting safety requirements, thereby improving the product's economy and competitiveness.

[0035] Furthermore, the method also includes: establishing an eleventh logical relationship between the rear wheel braking stiffness and the total braking force of the rear wheels; establishing a twelfth logical relationship between the clamping force of the caliper assembly corresponding to the rear wheels of the vehicle and the braking force at the first wheel end based on the preset braking system braking parameters; establishing a thirteenth logical relationship between the rear wheel braking stiffness and the clamping force of the caliper assembly corresponding to the rear wheels of the vehicle based on the eleventh and twelfth logical relationships; simulating the braking of the vehicle based on the thirteenth logical relationship to obtain the sixth relationship simulation curve corresponding to the thirteenth logical relationship, and determining the caliper specifications corresponding to the rear wheels based on the sixth relationship simulation curve.

[0036] Based on the aforementioned technical methods, by introducing a relationship model between rear wheel braking stiffness and caliper clamping force, and combining it with simulation analysis, the selection of rear wheel calipers can also be based on scientific evidence. This ensures, on the one hand, that the rear wheels can provide stable braking force under different braking conditions, avoiding braking imbalance or loss of control caused by inappropriate caliper specifications; on the other hand, by continuously optimizing caliper selection through simulation feedback, the braking system can minimize hardware costs while meeting safety requirements, thereby improving the product's economy and competitiveness.

[0037] Furthermore, the method also includes: establishing a fourteenth logical relationship between front wheel braking stiffness and front wheel dynamic axle load, and establishing a fifteenth logical relationship between front wheel dynamic axle load and rear wheel dynamic axle load based on the total load of the vehicle; establishing a sixteenth logical relationship between rear wheel dynamic axle load and rear wheel braking stiffness, and establishing a seventeenth logical relationship between front wheel braking stiffness and rear wheel braking stiffness based on the fourteenth, fifteenth, and sixteenth logical relationships; simulating vehicle braking based on the seventeenth logical relationship to obtain the simulation curve of the seventh relationship corresponding to the seventeenth logical relationship; and adjusting the initial braking system braking parameters and the initial drive motor energy recovery parameters based on the simulation curve of the seventh relationship to obtain the preset braking system braking parameters and the preset drive motor energy recovery parameters.

[0038] Based on the aforementioned technical methods, by introducing a relationship model between the dynamic axle load and braking stiffness of the front and rear wheels, and combining it with simulation analysis, the performance of the braking system in energy recovery mode becomes more balanced. This ensures, on the one hand, a more reasonable distribution of braking force between the front and rear wheels during energy recovery, avoiding vehicle handling instability caused by uneven energy recovery; on the other hand, by continuously optimizing braking and energy recovery parameters through simulation feedback, the system maintains good braking response and energy recovery efficiency under different driving scenarios, thereby improving the overall vehicle intelligence and user experience.

[0039] Secondly, embodiments of this application provide a braking deceleration determination device, which includes:

[0040] The acquisition module acquires the pedal travel generated by the driver pressing the electronic brake pedal in the electromechanical braking system during vehicle braking.

[0041] The determination module is used to determine the first wheel-end braking force provided by the clamping force of the brake assembly calipers of the vehicle's wheels based on the pedal travel using preset braking system braking parameters, and to determine the second wheel-end braking force provided by the torque generated by the energy recovery of the drive motor of the vehicle's wheels based on the pedal travel using preset drive motor energy recovery parameters.

[0042] The determination module is also used to determine the braking deceleration of the vehicle based on the first wheel-end braking force and the second wheel-end braking force of the wheels included in the vehicle.

[0043] Thirdly, embodiments of this application provide a device for determining braking deceleration, the device comprising: a processor, a memory, and a communication bus; the processor executes the running program stored in the memory to implement the above-mentioned method for determining braking deceleration.

[0044] Fourthly, embodiments of this application provide a computer-readable storage medium, characterized in that it stores a computer program thereon, which, when executed by a processor, implements the above-described method for determining braking deceleration.

[0045] The beneficial effects of this invention are:

[0046] (1) First, by acquiring the pedal travel of the electronic brake pedal, and combining it with the preset braking system parameters and drive motor energy recovery parameters, the first wheel-end braking force and the second wheel-end braking force of each wheel are calculated respectively. Then, the braking forces of all wheels are combined to obtain the overall braking deceleration of the vehicle. In this way, on the one hand, the logical relationship between the electronic brake pedal travel and the braking parameters enables accurate modeling of the braking force of each wheel of the vehicle, which is conducive to improving the accuracy of braking control; on the other hand, by considering both traditional braking and energy recovery as braking force sources, the actual front wheel braking performance of the vehicle can be more comprehensively reflected. Thus, under the function of the electronic brake force distribution system, the total braking force of the rear wheels determined based on the actual total braking force of the front wheels can effectively ensure the relationship between the front and rear wheels, avoid the tail-swing event caused by the rear wheels locking first, and thus improve the accuracy of braking deceleration.

[0047] (2) By constructing a multi-level logical relationship between pedal travel, braking force of each wheel, and vehicle braking deceleration, and by using simulation tools to verify the performance of these relationships under different braking scenarios, adaptive optimization of parameters can be achieved. In this way, on the one hand, potential braking performance problems can be identified in the design stage, reducing the cost of real vehicle testing; on the other hand, by continuously adjusting parameter configuration through simulation feedback, design parameters that achieve ideal performance can be found in a very short time, thereby improving product development efficiency and design accuracy, avoiding erroneous designs, and preventing the designed product from failing to meet the required braking performance.

[0048] (3) The constructed algorithm and logic are based on the measurable or test data of the product. The calculation formula has no correction parameters and is entirely based on the product design parameters. It conforms to kinematics and dynamics, and has high accuracy. The calculated results and expression methods can be obtained by testing with existing equipment. It can effectively carry out comparative evaluation and optimization analysis. At present, the electromechanical braking system products are still in the research stage and there are no products on the market. The analysis and evaluation method constructed in this application embodiment is also an analysis and evaluation means that is urgently needed in the research and development of electromechanical braking system component products at this stage.

[0049] (4) The constructed algorithm logic can be used for computer simulation. It can be integrated with simulations of acceleration, steering, etc. It can simulate the full working process of vehicle users driving on the road without the need for real vehicle verification. The performance of the whole vehicle can be analyzed with the help of computer. Attached Figure Description

[0050] Figure 1 A flowchart illustrating a method for determining braking deceleration provided in an embodiment of this application;

[0051] Figure 2 A schematic diagram of an exemplary electromechanical braking system provided for an embodiment of this application;

[0052] Figure 3 A schematic diagram of an exemplary electromechanical brake caliper assembly provided for an embodiment of this application;

[0053] Figure 4 A schematic diagram of an exemplary electronic brake pedal provided for an embodiment of this application;

[0054] Figure 5 A schematic diagram illustrating the working principle of an exemplary electromechanical braking system provided in this application embodiment;

[0055] Figure 6 A schematic flowchart illustrating an exemplary method for determining the total braking force of the first rear wheel, provided for an embodiment of this application;

[0056] Figure 7 A schematic diagram of an exemplary vehicle structure provided for an embodiment of this application;

[0057] Figure 8 This is an exemplary flowchart for determining the braking deceleration of a vehicle, provided as an embodiment of this application.

[0058] Figure 9 A schematic flowchart illustrating an exemplary method for determining the braking force at the first wheel end, provided for an embodiment of this application;

[0059] Figure 10 A schematic flowchart illustrating an exemplary method for determining the braking force at the second wheel end, provided for an embodiment of this application;

[0060] Figure 11 A schematic flowchart illustrating an exemplary method for determining braking system parameters and deceleration, provided for an embodiment of this application;

[0061] Figure 12 A basic functional logic diagram of an exemplary electronic braking system provided for embodiments of this application;

[0062] Figure 13 A simulation curve of an exemplary logical relationship provided for embodiments of this application. Figure 1 ;

[0063] Figure 14 A simulation curve of an exemplary logical relationship provided for embodiments of this application. Figure 2 ;

[0064] Figure 15 A simulation curve of an exemplary logical relationship provided for embodiments of this application. Figure 3 ;

[0065] Figure 16 A simulation curve of an exemplary logical relationship provided for embodiments of this application. Figure 4 ;

[0066] Figure 17 A simulation curve of an exemplary logical relationship provided for embodiments of this application. Figure 5 ;

[0067] Figure 18 A simulation curve of an exemplary logical relationship provided for embodiments of this application. Figure 6

[0068] Figure 19 A simulation curve of an exemplary logical relationship provided for embodiments of this application. Figure 7 ;

[0069] Figure 20A simulation curve of an exemplary logical relationship provided for embodiments of this application. Figure 8 ;

[0070] Figure 21 A schematic diagram of a braking deceleration determination device provided in an embodiment of this application;

[0071] Figure 22 This is a schematic diagram of a device for determining braking deceleration provided in an embodiment of this application. Detailed Implementation

[0072] The embodiments of the present invention will be described below with reference to the accompanying drawings and preferred embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be understood that the preferred embodiments are only for illustrating the present invention and not for limiting the scope of protection of the present invention.

[0073] Braking systems are mainly divided into hydraulic braking systems and pneumatic braking systems. Both of these systems require brake fluid or gas as the force transmission medium, and are large and complex to control. In order to adapt to and better realize the electric energy and L3 and above intelligent driving requirements of new energy vehicles, global automotive component suppliers and OEMs have successively been researching electromechanical braking systems that directly drive electric motors to provide torque and generate braking clamping force through mechanical transmission and gear shifting.

[0074] Currently, electromechanical braking systems are still in the functional prototype stage. Due to the differences in functional structure and operating principles, the existing matching analysis and optimization techniques for hydraulic and pneumatic braking systems are no longer applicable. The main reason is that hydraulic and pneumatic braking use brake fluid or gas as the braking force transmission medium, respectively, and adhere to hydraulic principles. In contrast, electromechanical braking primarily uses electrical energy as a power source, driving a motor via a program, and converting this energy into braking force through speed change and transmission. The two systems differ in structure, and consequently, in their operating methods.

[0075] This application provides a method for determining braking deceleration, implemented by a braking deceleration determination device. Figure 1 A flowchart illustrating a method for determining braking deceleration provided in an embodiment of this application is shown below. Figure 1 As shown, the process includes the following steps S101 to S103:

[0076] Step S101: Obtain the pedal travel generated by the driver pressing the electronic brake pedal in the electromechanical braking system during vehicle braking.

[0077] In embodiments of this application, the driver may be the person driving the vehicle. The driver brakes the vehicle by pressing the electronic brake pedal in the electromechanical braking system.

[0078] like Figure 2 As shown, the electromechanical braking system 20 includes: a left front brake assembly 21, a power supply 22, a right front brake assembly 23, a main controller 24, a power cable 25, a right rear brake assembly 26, a left rear brake assembly 27, and an electronic brake pedal 28, as shown. Figure 2 As shown, the electromechanical braking system has a simple structure; convenient and quick electronic control; powerful functions; supports the highest level of intelligent driving at present; and the braking energy is electric energy, so the braking energy used in new energy vehicles does not require additional conversion.

[0079] exist Figure 2 In the electromechanical braking system 20 shown, the core component is the electromechanical brake caliper assembly, which differs significantly from traditional brake calipers (hydraulic and pneumatic braking systems), such as... Figure 3 As shown, the electromechanical brake caliper assembly 30 comprises a transmission system 31, a motor 32, a caliper assembly 33, and a controller 34. Upon receiving a command from the main controller, the motor rotates forward or reverse, and the output torque is converted into clamping or releasing force of the caliper through the transmission system, thereby braking or releasing the brake.

[0080] in addition, Figure 2 The electronic brake pedal 28 in the system also differs from the traditional brake pedal, such as... Figure 4 As shown, the electronic brake pedal 28 comprises: a simulator 41, a base 42, a position sensor (built-in) 43, a controller (built-in) 44, a rotating shaft (built-in) 45, and a pedal arm 46. During braking, the movement stroke of the pedal arm 46 (pedal stroke) is reflected in the change of the electrical signal of the position sensor 43, which is processed by the controller and transmitted to the main controller 24.

[0081] In the embodiments of this application, the pedal travel is typically measured in millimeters, reflecting the braking intensity and demand. For example, the pedal travel is shorter when lightly pressed, and longer during emergency braking, thereby triggering a greater braking force response. Furthermore, the design of the electronic brake pedal also considers the feedback of the pedal to the driver's foot, allowing the driver to experience reasonable force feedback during pedaling and improving operational comfort.

[0082] In the embodiments of this application, after receiving the pedal travel signal, the main controller performs subsequent processing according to preset control logic. The pedal travel, as an input parameter of the entire braking process, directly affects the distribution of the brake assembly clamping force and energy recovery torque, and is the basis for calculating the vehicle's braking deceleration.

[0083] Step S102: Using preset braking system braking parameters and based on pedal travel, determine the first wheel-end braking force provided by the clamping force of the brake assembly calipers of the vehicle's wheels, and using preset drive motor energy recovery parameters and based on pedal travel, determine the second wheel-end braking force provided by the torque generated by the energy recovery of the drive motor of the vehicle's wheels.

[0084] In the embodiments of this application, the preset braking system parameters refer to the program parameters stored in the main controller of the electromechanical braking system for calculating the caliper clamping force. For example, the preset braking system parameters may include the braking system parameters of the vehicle's wheels. These braking system parameters are set by the control system and represent the proportional relationship of the clamping force that each brake assembly should apply under different pedal travel. For example, when the pedal travel increases, the loading coefficient can be a constant value, meaning that the clamping force of the brake assembly calipers increases accordingly, thereby generating a larger braking torque.

[0085] In the embodiments of this application, the brake assembly caliper clamping force refers to the force generated in the electromechanical braking system by the drive motor driving the transmission system, causing the calipers on the corresponding wheels to clamp the brake discs. Each vehicle wheel is equipped with a brake assembly caliper. After the driver depresses the pedal, generating a pedal travel, the brake assembly caliper clamping force corresponding to the pedal travel can be obtained based on preset braking system parameters. Therefore, the wheel-end braking force that can be provided is determined based on the clamping force of the wheel's brake assembly caliper.

[0086] In the embodiments of this application, the preset braking system braking parameters are program parameters that are pre-calibrated for the vehicle to determine the clamping force of the brake assembly caliper based on the pedal travel. In this way, during the braking process of the vehicle, after knowing the pedal travel, the clamping force of the brake assembly caliper can be directly obtained based on the calibrated braking system braking parameters, and then the wheel-end braking force that can be provided can be determined based on the clamping force of the brake assembly caliper.

[0087] In the embodiments of this application, the preset drive motor energy recovery parameters refer to the energy recovery control parameters stored in the drive motor controller. The preset drive motor energy recovery parameters determine the ability of the drive motor to reverse generate electricity and recover kinetic energy under different pedal strokes, thereby generating corresponding braking torque.

[0088] In the embodiments of this application, the torque generated by the energy recovery of the drive motor refers to the reverse torque generated during the braking process when the drive motor works in reverse to convert kinetic energy into electrical energy and store it in the battery. The process of the drive motor working in reverse to convert kinetic energy into electrical energy and store it in the battery also generates additional braking force to obtain the second wheel-end braking force.

[0089] In the embodiments of this application, the vehicle wheels can all have torque generated by the energy recovery of the drive motor. After the driver presses the pedal to generate the pedal travel, the braking deceleration determination device can obtain the torque generated by the energy recovery of the drive motor corresponding to the pedal travel based on the drive motor controller and the preset drive motor energy recovery parameters. Then, based on the torque generated by the energy recovery of the drive motor, the braking force generated on the wheel end, i.e. the second wheel end braking force, is determined.

[0090] like Figure 5 As shown, an exemplary braking implementation is as follows: Power supply 22 is wiredly connected to four brake assemblies (front brake assembly left 21, front brake assembly right 23, rear brake assembly right 26, and rear brake assembly left 27), electronic brake pedal 28, and main controller 24 to provide power. Main controller 24 is wiredly connected to electronic brake pedal 28 for wired signal transmission. The four brake assemblies are wirelessly connected to main controller 24 via CAN communication for wireless signal transmission. When the driver depresses the electronic brake pedal 28, the travel change signal of the pedal arm 46 is transmitted to the main controller 24 via a wired connection. Based on the travel distance, the main controller 24 sends braking commands and energy recovery requests to the caliper assembly controller and drive motor controller 51 via CAN wireless communication, according to the programmed requirements. The caliper controller drives the motor to engage the caliper brake and engage the caliper, while the drive motor controller 51 reverses to perform energy recovery and braking. Conversely, when the driver releases the electronic brake pedal 28, the release travel signal of the pedal arm 46 is transmitted to the main controller 24. The main controller 24 sends a release brake command to the caliper assembly controller and a release energy recovery command to the drive motor controller 51, according to the programmed requirements. The caliper assembly controller drives the motor to engage the caliper and engage the drive motor to release energy recovery and reverse braking. Wheel speed sensors are installed on the brake assembly, and the wheel speed signals are directly transmitted to the caliper controller via a wired connection. The caliper controller then transmits the signals to the main controller 24 via CAN communication. The main controller 24 performs calculations based on the wheel speed signal to determine the vehicle's operating status, and sends execution commands to the caliper assembly motor controller as needed to realize a series of functions such as the Anti-lock Braking System (ABS), Electronic Brakeforce Distribution (EBD), Electronic Stability Control (ESC), and Traction Control System (TCS).

[0091] Due to the need for braking safety, practical applications often require a dual redundancy design. Sensors, controllers, and wired and wireless connections are all configured in dual ways so that if one fails, the other can continue to work to maintain functionality.

[0092] Step S103: Determine the total braking force of the front wheels based on the braking force at the first wheel end and the braking force at the second wheel end corresponding to the front wheels of the vehicle.

[0093] In the embodiments of this application, the braking deceleration determining device determines the sum of the braking force at the first wheel end and the braking force at the second wheel end corresponding to the front wheel of the vehicle as the total braking force of the front wheel.

[0094] In the embodiments of this application, the total front wheel braking force refers to the sum of the total clamping forces generated by the left and right front wheels of the vehicle during braking. By separately collecting the wheel-end braking forces of the left and right front wheels, the system can accurately calculate the total front wheel braking force for further analysis of the vehicle's braking performance.

[0095] For example, the braking deceleration determination device can determine the total braking force of the front wheels by summing the braking force at the first wheel end and the braking force at the second wheel end corresponding to the front wheels of the vehicle. For example, see formula (1):

[0096] F f =F flμ +F frμ +N flμ +N frμ (1);

[0097] Among them, F f For the total braking force of the front wheels, N flμ Braking force at the second wheel end of the left front wheel, N frμ The braking force at the second wheel end of the right front wheel is provided by the torque generated by the energy recovery of the drive motor. fl F fr These are the clamping forces of the left caliper and the right caliper of the front brake assembly, respectively.

[0098] Step S104: Under the function of the electronic brake force distribution system, the total braking force of the first rear wheel is determined based on the total braking force of the front wheels, and the braking deceleration of the vehicle is determined based on the total braking force of the front wheels and the total braking force of the first rear wheels.

[0099] In the embodiments of this application, the calculation method for braking deceleration differs under different application scenarios. For example, when neither the front nor rear wheels of the vehicle are locked, the total braking force of the entire vehicle—the sum of the braking forces at the four wheel ends (left front wheel, right front wheel, left rear wheel, and right rear wheel)—divided by the total mass of the vehicle, yields the overall braking deceleration. If the rear wheels are close to locking while the front wheels are not, considering the requirements of GB21670-2012, the rear wheels must not lock up first. If the rear wheels are close to locking up, the increase in braking force under the action of EBD is limited, keeping the tires at a relatively low slippage and maintaining vehicle stability in the driving direction, preventing fishtailing. It is necessary to set the EBD's control of the rear wheels to be ideal, conforming to the ideal braking I-curve of braking theory, with the rear wheel slip ratio consistent with the front wheels, and the friction provided by the tires and road surface for vehicle deceleration also consistent. The braking force at the wheel ends of the rear wheels can be determined based on the first and second wheel-end braking forces of the front wheels, thereby determining the vehicle's braking deceleration.

[0100] In the embodiments of this application, firstly, the pedal travel serves as the initial input and forms the basis for all subsequent calculations. Secondly, based on the pedal travel and preset parameters, the braking forces at the first and second wheels of the vehicle—the left front wheel, the right front wheel, the left rear wheel, and the right rear wheel—are calculated respectively. Finally, the braking forces at the first and second wheels are added together, and combined with the vehicle's mass, the final braking deceleration is obtained. This entire process achieves closed-loop control from user input to system output, ensuring both safe and efficient braking performance.

[0101] Thus, by first acquiring the pedal travel of the electronic brake pedal, and combining it with preset braking system parameters and drive motor energy recovery parameters, the first and second wheel-end braking forces of each wheel are calculated separately. Then, the braking forces of all wheels are combined to obtain the overall braking deceleration of the vehicle. In this way, on the one hand, the logical relationship between the electronic brake pedal travel and braking parameters enables precise modeling of the braking force of each wheel, which helps improve the accuracy of braking control; on the other hand, by simultaneously considering both traditional braking and energy recovery braking sources, it can more comprehensively reflect the actual front wheel braking performance of the vehicle. Therefore, under the function of the electronic brake force distribution system, the total rear wheel braking force determined based on the actual total front wheel braking force can effectively ensure the relationship between the front and rear wheels, avoiding tail-swing events caused by rear wheel lock-up, thereby improving the accuracy of braking deceleration.

[0102] In some embodiments, when the braking deceleration determining device performs the step S104 above, "determining the total braking force of the first rear wheel based on the total braking force of the front wheels," as follows: Figure 6 As shown, the following steps S601 and S602 can also be performed:

[0103] Step S601: Based on the total braking force of the front wheels, determine the braking stiffness of the front wheels, and then determine the braking stiffness of the front wheels as the braking stiffness of the rear wheels.

[0104] In the embodiments of this application, the total braking force of the front wheels is substituted into the algorithm for determining the front wheel braking stiffness. For example, the determination of the front wheel braking stiffness can be implemented as follows: a first parameter is determined based on the vehicle's gravity, center of gravity distance from the rear axle, and front and rear wheel track; a second parameter is determined based on the vehicle's gravity, center of gravity height, and front and rear wheel track; a third parameter is determined based on the vehicle's gravity, total braking force of the front wheels, and front and rear wheel track; and the front wheel braking stiffness is determined based on the first, second, and third parameters.

[0105] The determination of the front wheel braking stiffness described above can be achieved using formula (2):

[0106]

[0107] Among them, Z f M represents the front wheel braking stiffness, M represents the total vehicle load (in kg), and L represents the front and rear wheel track width (see [reference]). Figure 7 In point 71), g is the acceleration due to gravity, taken as 9.8 m / s². 2 b is the distance from the center of mass to the rear axis, and H is the height of the center of mass (see [reference]). Figure 7 72), unit: m, As the first parameter, For the second parameter, This is the third parameter.

[0108] In the embodiments of this application, in order to prevent the rear wheels from locking up first and to maintain the ideal wheel slip ratio, the front wheel braking stiffness can be determined as the rear wheel braking stiffness.

[0109] Step S602: Determine the total braking force of the first rear wheel based on the rear wheel braking stiffness.

[0110] In the embodiments of this application, the braking deceleration determination device can substitute the rear wheel braking stiffness into the algorithm of the total braking force of the first rear wheel to determine the total braking force of the first rear wheel.

[0111] For example, the method for determining the total braking force of the rear wheels may be as follows: a sixth parameter is determined based on the vehicle's weight, center of gravity distance from the front axle, front wheel braking stiffness, and front and rear wheel track width; a seventh parameter is determined based on the vehicle's weight, center of gravity height, rear wheel braking stiffness, and the ratio of front and rear wheel track width; and the first total braking force of the rear wheels is determined based on the sixth and seventh parameters.

[0112] The method for achieving the total braking force of the first rear wheel as described above can be shown in formula (3):

[0113]

[0114] Among them, F r1 c is the total braking force of the first rear wheel, and c is the distance from the center of gravity to the front axle (see...). Figure 7 73), unit: m, H is the height of the vehicle's center of gravity (see 73). Figure 7 74 in the text), unit: m, The sixth parameter, This is the seventh parameter.

[0115] Accordingly, based on the total braking force of the front wheels and the total braking force of the first rear wheels, the method for determining the vehicle's braking deceleration can be found in formula (4):

[0116]

[0117] Where a is the braking deceleration and M is the total load of the vehicle.

[0118] Thus, under the function of the electronic brake-force distribution system, the front wheel braking stiffness determined based on the actual total front wheel braking force is more accurate than that of theoretical simulations. Furthermore, directly using the front wheel braking stiffness as the rear wheel braking stiffness to determine the first total rear wheel braking force ensures consistent braking between the front and rear wheels, enabling simultaneous wheel lock-up and preventing tail-swing caused by rear wheel lock-up. Moreover, the calculation of front wheel braking stiffness based on the vehicle's characteristics does not consider the coefficient related to tire-road friction, and this coefficient is relatively small. Using the coefficient related to tire-road friction to determine the total front wheel braking force could easily lead to slippage. Using a smaller front wheel braking stiffness to determine the total front wheel braking force effectively reduces the slippage rate. In addition, directly determining the front wheel braking stiffness as the rear wheel braking stiffness, and then using this rear wheel braking stiffness to determine the first total rear wheel braking force, ensures consistent front and rear wheel braking stiffness and synchronized braking, effectively preventing rear wheel lock-up.

[0119] In some embodiments, such as Figure 8 As shown, the method for determining braking deceleration can also perform the following steps S801 and S802:

[0120] Step S801: When the vehicle is in the function of the anti-lock braking system, determine the total braking force of the second rear wheel based on the braking force at the first wheel end and the braking force at the second wheel end corresponding to the rear wheel of the vehicle.

[0121] In the embodiments of this application, if the vehicle is under the function of the anti-lock braking system, the total braking force of the second rear wheel is determined based on the braking force at the first wheel end and the braking force at the second wheel end corresponding to the rear wheel of the vehicle. An exemplary implementation method is shown in formula (5):

[0122] F r2 =F rlμ +F rrμ +N rlμ +N rr μ (5);

[0123] Among them, F r2 For the second rear wheel total braking force, F rl F rr These are the clamping forces of the left caliper and the right caliper of the rear brake assembly, respectively, in N. rlμ N rrμ These are the braking forces at the second wheel end of the left rear wheel provided by the torque generated by the energy recovery of the drive motor, and the braking forces at the second wheel end of the right rear wheel provided by the torque generated by the energy recovery of the drive motor, respectively, in N.

[0124] Step S802: Determine the vehicle's braking deceleration based on the total braking force of the front wheels and the total braking force of the second rear wheels.

[0125] For example, the implementation can be seen in formula (6):

[0126]

[0127] Among them, F r2 It provides the total braking force for the second rear wheel.

[0128] In some embodiments, the preset braking system braking parameters include the braking coefficients corresponding to the vehicle wheels. When the braking deceleration determining device performs step S102 above, "using the preset braking system braking parameters and based on the pedal travel, to determine the first wheel-end braking force provided by the brake assembly caliper clamping force of the vehicle wheels," as... Figure 9 As shown, the process may include the following steps S901 and S902:

[0129] Step S901: For the vehicle's wheels, the product of the braking coefficient corresponding to the wheel and the pedal travel is determined as the clamping force of the brake assembly caliper corresponding to the wheel.

[0130] In the embodiments of this application, the preset braking system braking parameters include the braking coefficients corresponding to the vehicle's wheels, including the front left wheel, front right wheel, rear left wheel, and rear right wheel. Therefore, the preset braking system braking parameters include the braking coefficient (K1) of the front brake assembly left based on pedal travel, the braking coefficient (K2) of the front brake assembly right based on pedal travel, the braking coefficient (K3) of the rear brake assembly left based on pedal travel, and the braking coefficient (K4) of the rear brake assembly right based on pedal travel. Alternatively, the clamping force of the corresponding brake assembly caliper for the front wheels can be determined first. For example, for the front wheels of the vehicle, the product of the braking coefficient corresponding to the wheel and the pedal travel can be determined as the clamping force of the corresponding brake assembly caliper for the front wheels. Subsequently, when using the rear wheels, the product of the braking coefficient corresponding to the wheel and the pedal travel can be determined as the clamping force of the corresponding brake assembly caliper for the rear wheels.

[0131] In the embodiments of this application, the pedal travel (pedal arm movement) S is converted into the brake assembly caliper clamping force to brake the wheel. The logical relationship between the brake assembly caliper clamping force and the pedal travel S is given by formula (7):

[0132]

[0133] Wherein, K1, K2, K3, and K4 represent the braking coefficients based on pedal travel for the left and right sides of the front brake assembly, the left and right sides of the rear brake assembly, respectively. These braking coefficients are pre-calibrated software parameters stored in the main controller, and the unit is N / mm. fl F fr F rl F rr These are the clamping forces of the left caliper of the front brake assembly, the right caliper of the front brake assembly, the left caliper of the rear brake assembly, and the right caliper of the rear brake assembly.

[0134] Step S902: For the vehicle's wheels, determine the first wheel-end braking force corresponding to the wheel based on the clamping force of the brake assembly caliper corresponding to the wheel and the corresponding wheel rotation ratio.

[0135] In the embodiments of this application, the first wheel-end braking force is the force that ultimately acts on the wheel and produces a deceleration effect, and the unit of this force is Newtons (N). The first wheel-end braking force is calculated from the clamping force of the brake assembly caliper through the wheel rotation ratio, representing the actual braking force transmitted to the wheel by the braking system. By calculating the clamping force of the brake assembly caliper corresponding to a certain wheel and its corresponding wheel rotation ratio, the first wheel-end braking force corresponding to that wheel can be determined. This process can accurately quantify the actual role played by each wheel during braking, which is helpful for subsequent in-depth analysis of the overall braking performance of the vehicle.

[0136] Thus, by combining the clamping force of the brake assembly calipers with the wheel rotation ratio, the first wheel-end braking force of each wheel can be accurately calculated. This method of calculating the first wheel-end braking force of each wheel by combining the clamping force of the brake assembly calipers with the wheel rotation ratio achieves precise control of brake distribution.

[0137] In some embodiments, the wheel rotation ratio includes the speed conversion factor corresponding to the wheel and the wheel rolling radius. When performing the above step S902, the braking deceleration determining device may also perform the following steps: determining the actual caliper clamping force corresponding to the wheel as the product of the caliper clamping force of the brake assembly corresponding to the wheel and the corresponding brake braking performance; determining the wheel rotation ratio corresponding to the wheel as the ratio of the speed conversion factor corresponding to the wheel and the corresponding wheel rolling radius; and determining the first wheel end braking force corresponding to the wheel as the product of the wheel rotation ratio corresponding to the wheel and the corresponding actual caliper clamping force.

[0138] In the embodiments of this application, the braking deceleration determining device determines the actual caliper clamping force corresponding to the wheel as the product of the clamping force of the brake assembly caliper corresponding to the wheel and the corresponding brake braking performance. Here, considering that the clamping force of the brake assembly caliper may not necessarily provide the braking force at the wheel end, a parameter of the brake braking performance is set to determine the actual caliper clamping force corresponding to the wheel.

[0139] In the embodiments of this application, the ratio of the speed conversion factor to the wheel rolling radius reflects the wheel's response sensitivity to input signals (such as pedal travel). A higher ratio indicates a faster wheel response to pedal operation, which helps improve the driver's perception of braking response and control precision. As a component of the wheel rotation ratio, the ratio of the speed conversion factor to the wheel rolling radius provides a crucial input for subsequent braking force calculations. This approach considers different vehicle models, tire configurations, and driving conditions, thereby enabling a more flexible braking control strategy and expanding its application scenarios.

[0140] In the embodiments of this application, the first wheel-end braking force refers to the direct braking force borne by the wheel under current braking conditions. This value is equal to the product of the wheel rotation ratio and the actual caliper clamping force. The first wheel-end braking force directly determines the wheel's ability to decelerate during braking and is an important indicator in the evaluation of overall vehicle braking performance.

[0141] In this embodiment, the wheel rotation ratio is subdivided into a speed conversion factor and a wheel rolling radius. The actual caliper clamping force is defined as the product of the brake assembly caliper clamping force and the brake braking performance. Finally, the actual caliper clamping force is multiplied by the wheel rotation ratio to obtain the first wheel-end braking force, which can improve the accuracy of braking force calculation.

[0142] For example, the method for determining the first wheel-end braking force corresponding to a wheel based on the clamping force of the brake assembly caliper corresponding to the wheel and the corresponding wheel rotation ratio is shown in formula (8):

[0143]

[0144] Among them, F fl F fr F rl F rr These are the clamping forces of the left caliper in the front brake assembly, the right caliper in the front brake assembly, the left caliper in the rear brake assembly, and the right caliper in the rear brake assembly. F flμ F frμ F rlμ F rrμ These refer to the braking forces provided by the brake assembly calipers at the first wheel end of the front left wheel, the first wheel end of the front right wheel, the first wheel end of the rear left wheel, and the first wheel end of the rear right wheel, respectively, in μ. f μ r : These refer to the braking performance of the front brake and the braking performance of the rear brake, respectively. R f R r : These refer to the rolling radius of the front wheel and the rolling radius of the rear wheel, respectively. f r r These refer to the front wheel speed conversion factor and the rear wheel speed conversion factor, respectively.

[0145] In this way, the differences in braking response between different wheels can be taken into account, which can better match the braking requirements of the vehicle under actual working conditions. On the other hand, by combining the physical characteristics of the wheel rotation ratio, it can be ensured that the calculation of the braking force at the first wheel end is more in line with the mechanical principles, thereby improving the accuracy of braking deceleration prediction.

[0146] In some embodiments, the preset drive motor energy recovery parameters include the energy recovery braking coefficients corresponding to the vehicle's wheels. When the braking deceleration determining device performs the step S102 described above, "using the preset drive motor energy recovery parameters and based on the pedal travel, determine the second wheel-end braking force provided by the torque generated by the drive motor energy recovery of the vehicle's wheels," as... Figure 10 As shown, the following steps S1001 and S1002 can also be performed:

[0147] Step S1001: For the vehicle's wheels, determine the torque generated by the energy recovery of the drive motor corresponding to the wheel based on the product of the energy recovery braking coefficient of the wheel and the pedal travel.

[0148] In the embodiments of this application, for the wheels of a vehicle, the torque generated by the energy recovery of the drive motor corresponding to the wheel is determined based on the product of the energy recovery braking coefficient of the wheel and the pedal travel.

[0149] For example, the method for determining the torque generated by the energy recovery of the drive motor corresponding to the wheel based on the product of the energy recovery braking coefficient of the wheel and the pedal travel is shown in formula (9):

[0150]

[0151] Among them, M fl M fr M rl M rr These are the torques (M) generated by the energy recovery of the front axle drive motor. fl and M fr ) and the torque generated by energy recovery from the rear axle drive motor (M rl and M rr (Braking torque acting on the front and rear axles), unit: N·m, S is the pedal travel, n1 and n2 are the energy recovery braking coefficients of the front axle drive motor and the rear axle drive motor based on the pedal travel, respectively, formed by the main controller software, unit: N·m / mm.

[0152] Step S1002: For the vehicle's wheels, determine the ratio of the torque corresponding to the wheel to the corresponding wheel rolling radius as the braking force at the second wheel end corresponding to the wheel.

[0153] In the embodiments of this application, for the wheels of a vehicle, the ratio of the torque corresponding to the wheel to the rolling radius of the corresponding wheel is determined as the second wheel-end braking force corresponding to the wheel.

[0154] For example, the method of determining the braking force at the second wheel end corresponding to the wheel by the ratio of the torque corresponding to the wheel to the rolling radius of the corresponding wheel is shown in formula (10):

[0155]

[0156] Where, N flμ N frμ N rlμ N rrμ These are the braking forces provided by the torque generated by the energy recovery of the drive motor at the second wheel end of the front left, front right, rear left, and rear right wheels, respectively, in N; R f R r : These refer to the rolling radius of the front wheel and the rolling radius of the rear wheel, respectively, in meters.

[0157] Thus, by introducing an energy recovery braking coefficient and combining it with pedal travel, the energy recovery torque of each wheel is calculated, and then further converted into the braking force at the second wheel end. Based on the preset energy recovery parameters of the drive motor and the pedal travel, the energy recovery intensity can be adjusted to improve the driving experience. Furthermore, by normalizing the torque through the wheel rolling radius, the expression of the braking force at the second wheel end is consistent with that at the first wheel end, which facilitates subsequent summation calculations and improves the coordination and consistency of the entire braking deceleration calculation process.

[0158] like Figure 11 As shown, the exemplary method for determining the braking deceleration includes the following steps S1101 to S1113:

[0159] Step S1101: Determine the pedal travel.

[0160] Here, the device for determining braking deceleration can obtain the pedal force 111 generated by the driver pressing the electronic brake pedal in the electromechanical braking system during vehicle braking, and then determine the pedal stroke 113 based on the pedal force 111 and the preset elastic coefficient 112. The determination method is shown in formula (11):

[0161] F = S × K (11);

[0162] Where F is the pedal force and K is the preset elastic coefficient.

[0163] Step S1102: Determine the clamping force of the brake assembly calipers of the vehicle's wheels.

[0164] Here, the device for determining braking deceleration can input the pedal travel 113 and the preset braking system braking parameters 114 (K1, K2, K3, K4) into the above formula (1) to determine the clamping force 115 of the brake assembly calipers of the vehicle's wheels, and thus obtain F. fl F fr F rlF rr .

[0165] Step S1103: Determine the torque generated by the energy recovery of the drive motor of the vehicle's wheels.

[0166] Here, the braking deceleration determination device can input the pedal travel 113 and the preset drive motor energy recovery parameters 116 (n1, n2) into the above formula (9) to obtain the torque 117 generated by the energy recovery of the vehicle's wheel drive motor, and thus obtain M. fl M fr M rl M rr .

[0167] Step S1104: Determine the braking force at the first wheel end of the vehicle's wheels.

[0168] Here, the braking deceleration determination device measures the clamping force of the brake assembly calipers of the vehicle's wheels at 115 (F). fl F fr F rl F rr The input is entered into formula (8) to determine the braking force 118 (F) at the first wheel end of the vehicle's wheels. flμ F frμ F rlμ F rrμ ).

[0169] Step S1105: Determine the braking force at the second wheel end of the vehicle's wheels.

[0170] Here, the braking deceleration determination device uses the torque 117 (M) generated by the energy recovery of the vehicle's wheel drive motor. fl M fr M rl M rr The input is entered into the above formula (10) to determine the braking force 119 at the second wheel end of the vehicle's wheels.

[0171] (N flμ N frμ N rlμ N rrμ ).

[0172] Step S1106: Determine the total braking force of the front wheels.

[0173] Here, the braking deceleration determination device is based on the above formula (1), and the sum of the braking force at the first wheel end and the braking force at the second wheel end of the front wheel is determined as the total braking force of the front wheel 1110 (F). f ).

[0174] Step S1107: Determine the front wheel braking stiffness.

[0175] Here, the braking deceleration is determined based on the above formula (2), substituting the total braking force of the front wheels to obtain the front wheel braking stiffness 1111(Z f ).

[0176] Step S1108: Determine the total braking force of the first rear wheel.

[0177] Here, the device for determining braking deceleration is based on the above formula (3), substituting the total braking force of the front wheels as the total braking force of the rear wheels to obtain the first total braking force of the rear wheels 1112(F). r2 ).

[0178] Step S1109: Determine the total braking force of the second rear wheel.

[0179] Here, the braking deceleration determination device is based on the above formula (5), and the sum of the braking force at the first wheel end and the braking force at the second wheel end of the rear wheel is determined as the total braking force of the second rear wheel 1113(F). r1 ).

[0180] Step S1110: Is the total braking force of the first rear wheel greater than the total braking force of the second rear wheel?

[0181] Here, if yes, the second rear wheel total braking force 1113 is determined as the target rear wheel total braking force; if no, the first rear wheel total braking force 1112 is determined as the target rear wheel total braking force.

[0182] Step S1111: Determine the braking deceleration.

[0183] Here, the braking deceleration determination device substitutes the target total braking force of the rear wheels and the total braking force of the front wheels into the above formula (7) to obtain the braking deceleration.

[0184] Based on the active control principles of EBD and ABS, the total braking force of the front wheels, 1110 (F), is calculated using the pedal force input from the brake pedal and relevant parameters of the braking system. f ), with a total braking force of 1110 (F) from the front wheels f Substituting into formula (2), the front wheel braking stiffness 1112(Z) is calculated. f Based on the EBD ideal control principle, the rear wheel braking stiffness is the same as the front wheel at this time, and the front wheel braking stiffness is 1111(Z). f Substituting into formula (3), the total braking force of the first rear wheel 1112 (F) can be calculated. r1 Then, by using formula (7), the braking deceleration of the vehicle under EBD active control can be calculated.

[0185] If both the front and rear wheels lock up, the braking deceleration is related to the tire-road adhesion coefficient and the ABS execution efficiency. An exemplary relationship can be found in formula (12):

[0186]

[0187] Where a is the braking deceleration and u is the road adhesion coefficient. 'g' represents the ABS execution efficiency, and 'g' represents the acceleration due to gravity.

[0188] like Figure 12 As shown, after the driver 121 depresses the electronic brake pedal 28 with a pedal force F, the electronic brake pedal 28 sends a pedal stroke S to the main controller 24 and the drive motor controller 51. The main controller 24 calculates the clamping force 122 (F) of the left caliper of the front brake assembly based on the pedal stroke S and formula (7). fl Front brake assembly right caliper clamping force 123 (F) fr Rear brake assembly left caliper clamping force 124 (F) rl Rear brake assembly right caliper clamping force 125 (F) rr ), and then based on F fl F fr F rl F rr The braking force 126 (F) provided by the brake assembly caliper to the first wheel end of the left front wheel is calculated using the formula (8) above. flμ ), Braking force at the first wheel end of the right front wheel: 127 (F) frμ ), the first wheel-end braking force of the left rear wheel is 128 (F) rlμ ), Braking force at the first wheel end of the right rear wheel 129 (F) rrμ The drive motor controller 51 calculates the torque 1210 (M) generated by the energy recovery of the front axle drive motor based on the pedal travel S and formula (9). fl and M fr ) and the torque generated by energy recovery from the rear axle drive motor 1211 (M rl and M rr ); and further based on M fl M fr M rl M rr The braking force 1212 (N) provided by the torque generated by the energy recovery of the drive motor to the second wheel end of the left front wheel is calculated using the above formula (10). flμ ), Braking force at the second wheel end of the right front wheel: 1213 (N) frμ ), the braking force at the second wheel end of the left rear wheel is 1214 (N) rlμ ), Braking force at the second wheel end of the right rear wheel: 1215 (N) rrμ The second wheel-end braking force is used to determine the braking deceleration of vehicle 1216. Finally, the braking force at the first and second wheel-ends of the vehicle's wheels is used to determine the braking deceleration of vehicle 1216.

[0189] In some embodiments, the braking deceleration determination device may further perform the following steps: acquiring the pedal travel generated by the driver pressing the electronic brake pedal in the electromechanical braking system during vehicle braking; using initial braking system braking parameters, based on the pedal travel, determining the first wheel-end braking force provided by the brake assembly caliper clamping force of the vehicle's wheels, and using initial drive motor energy recovery parameters, based on the pedal travel, determining the second wheel-end braking force provided by the torque generated by the drive motor energy recovery of the vehicle's wheels; determining the vehicle's braking deceleration based on the first and second wheel-end braking forces of the wheels included in the vehicle; evaluating whether the braking performance requirements are met based on the logical relationship between braking deceleration and pedal travel, pedal force, and brake assembly caliper clamping force (see the first to seventeenth logical relationships discussed below, and the evaluation items shown in Table 1); if not, adjusting the relevant braking system parameters (initial braking system braking parameters, initial drive motor energy recovery parameters, and initial elastic coefficient) until the requirements are met, and then using the obtained braking system parameters (preset braking system braking parameters, preset drive motor energy recovery parameters, and preset elastic coefficient) for product design. This application models the braking force of each wheel of a vehicle by measuring the pedal travel, which helps to improve the accuracy of braking control. With the help of a computer and programming, the input parameters are automatically calculated and analyzed, improving design efficiency and accuracy, enhancing braking performance, and eliminating redundancy to save costs.

[0190] In this way, on the one hand, by establishing a logical relationship between the electronic brake pedal travel and braking parameters, precise modeling of the braking force of each wheel of the vehicle is achieved, which helps improve the accuracy of theoretical calculations and analysis. On the other hand, by simultaneously considering both traditional braking and energy recovery as braking force sources, the actual braking performance of the vehicle can be more comprehensively reflected. The results of theoretical calculations and analysis are closer to the actual dynamic braking situation of the vehicle, making them more valuable in the design process, avoiding erroneous designs, and preventing products from failing to meet braking performance requirements. All parameters are calculated based on measurable or testable data of the product. The calculation formulas have no correction parameters, fully conform to kinematics and dynamics, and have high accuracy. The calculated results and expressions can all be obtained through testing with existing equipment, allowing for effective comparative evaluation and optimization analysis.

[0191] In the embodiments of this application, ideally, neither the front nor rear wheels lock up; in cases where the front wheels don't lock up but the rear wheels are close to locking up, the EBD function controls wheel slip ratio and vehicle stability; and in cases where both the front and rear wheels lock up, the ABS function maintains vehicle stability. The driver applies any possible pedal travel in these three scenarios, and the functional and logical relationships between the braking system and vehicle parameters and the actual vehicle dynamic braking deceleration under ABS control are established. Simulations are built based on these functional relationships. The braking system and vehicle system parameters can be adjusted. Based on braking performance requirements, adjusting the parameters can obtain braking deceleration consistent with actual testing and meeting performance requirements.

[0192] In some embodiments, the device for determining braking deceleration may further perform the following steps: establishing a first logical relationship between pedal travel and braking force at the first wheel end based on initial braking system parameters, and establishing a second logical relationship between pedal travel and braking force at the second wheel end based on initial drive motor energy recovery parameters; establishing a third logical relationship between pedal travel and vehicle braking deceleration based on the first and second logical relationships; simulating vehicle braking based on the third logical relationship for different braking scenarios to obtain a simulation curve of the first relationship corresponding to the third logical relationship; and adjusting the initial braking system parameters and initial drive motor energy recovery parameters based on the simulation curve of the first relationship to obtain preset braking system parameters and preset drive motor energy recovery parameters.

[0193] In the embodiments of this application, a logical relationship between pedal travel and braking deceleration, namely a third logical relationship, is established based on the initial braking system braking parameters and the initial drive motor energy recovery parameters. For example, a logical relationship between pedal travel and braking deceleration is constructed based on the above formulas (1) to (11). Then, simulations are performed based on the third logical relationship for different braking scenarios. For example, braking scenarios may include no energy recovery under no-load conditions, energy recovery under no-load conditions, no energy recovery under full-load conditions, and the deceleration corresponding to the pedal travel under full-load conditions with energy recovery. Thus, the total vehicle load in the third logical relationship varies, and if there is no energy recovery, the total braking force at the second wheel end is not considered. An example simulation curve is shown below. Figure 13 As shown, simulation curves 131, 132, 133, 134, and 134 are shown for the braking deceleration corresponding to the pedal travel under no-load conditions and without energy recovery, respectively. The horizontal axis represents the pedal travel, and the vertical axis represents the braking deceleration.

[0194] like Figure 13As shown, the simulation curve of this first relationship can be used to evaluate whether the deceleration corresponding to the pedal travel meets the requirements of pedal feel, and to evaluate whether the braking deceleration formed by the main controller's loading of energy recovery and the loading of the brake changes smoothly with pedal travel, thus determining the rationality of the program parameters. The program parameters are K, K1, K2, K3, K4, n1, and n2 mentioned above. Figure 13 As shown, if the simulated braking deceleration curves 131 (no-load, no-energy-recovery pedal travel), 132 (no-load, energy-recovery pedal travel), 133 (full-load, no-energy-recovery pedal travel), and 134 (full-load, energy-recovery pedal travel) are not within the marked intervals of 135 and 136, then parameters K, K1, K2, K3, K4, n1, and n2 will be adjusted so that all data lines fall within the marked intervals of 135 and 136.

[0195] In this way, by constructing a multi-level logical relationship between pedal travel, braking force of each wheel, and vehicle braking deceleration, and by using simulation tools to verify the performance of these relationships under different braking scenarios, adaptive optimization of parameters can be achieved. This approach allows for the identification of potential braking performance issues during the design phase, reducing real-vehicle testing costs. Furthermore, by continuously adjusting parameter configurations through simulation feedback, the braking system can maintain stable and reliable performance under various complex operating conditions, thereby improving product development efficiency and quality.

[0196] In some embodiments, the device for determining braking deceleration may further perform the following steps: establishing a fourth logical relationship between pedal force and pedal travel based on the initial elastic coefficient of the electronic brake pedal; establishing a fifth logical relationship between pedal force and braking deceleration based on the fourth logical relationship; simulating vehicle braking based on the fifth logical relationship for different braking scenarios to obtain a second relationship simulation curve corresponding to the fifth logical relationship; adjusting the initial braking parameters based on the second relationship simulation curve to obtain preset braking parameters; wherein the initial braking parameters include at least one of the following: initial braking system braking parameters, initial drive motor energy recovery parameters, and initial elastic coefficient.

[0197] In the embodiments of this application, the braking deceleration determination device can establish a fifth logical relationship between pedal force and braking deceleration based on the above formulas (1) to (11), and then simulate the vehicle braking based on the fifth logical relationship to obtain the second relationship simulation curve corresponding to the fifth logical relationship; based on the second relationship simulation curve, for example, the second relationship simulation curve is as follows: Figure 14As shown, simulation curves for braking deceleration are presented: 141 for pedal force under no-load conditions and without energy recovery; 142 for pedal force under no-load conditions and with energy recovery; 143 for pedal force under full-load conditions and without energy recovery; and 144 for pedal force under full-load conditions and with energy recovery. The horizontal axis represents pedal force (N), and the vertical axis represents deceleration (g), where 1g = 9.8 m / s². 2 Generally through Figure 14 It can assess whether the braking deceleration corresponding to the pedal force meets the requirements of pedal feel, and can evaluate whether the braking deceleration formed by the main controller's loading of energy recovery and the loading of the brake changes smoothly with pedal force, in order to determine the rationality of the program parameters. When Figure 13 If the requirements are met, parameter K should usually be adjusted to adjust the pedal force F, ensuring all data lines fall within the double-dotted line range of 145 and 146. If the smoothness is not good, n1 and n2 need to be adjusted, while observing the results. Figure 13 Does it still meet the requirements? Figure 13 This does not meet the requirements; K, K1, K2, K3, and K4 need to be adjusted simultaneously.

[0198] In the embodiments of this application, based on the fifth logical relationship, the braking of the vehicle is simulated to obtain the second relationship simulation curve corresponding to the fifth logical relationship. The second relationship simulation curve can be the relationship curve between pedal force and deceleration without energy recovery and with braking efficiency of 70%, such as... Figure 15 As shown, the horizontal axis represents the pedal force (N), and the vertical axis represents the braking deceleration (g), where 1g = 9.8 m / s². 2 The simulation curve 151 shows the braking deceleration corresponding to the pedal force under no-load conditions, and the simulation curve 152 shows the braking deceleration corresponding to the pedal force under full load conditions. In the figure, 153 and 154 are the inflection points under no-load and full load conditions, respectively. This chart is used to evaluate whether there is an imbalance in the brake pedal force or the brake cannot lock up after the performance declines.

[0199] Thus, by introducing the logical relationship between pedal force and pedal travel, and further extending it to the relationship between pedal force and braking deceleration, braking performance evaluation becomes more comprehensive. This allows for simulation analysis of the vehicle's braking response under different pedal force inputs, helping to optimize pedal feel design and improve the driver's operating experience.

[0200] In some embodiments, after establishing the logical relationship between pedal force and pedal travel, the braking deceleration determination device may further perform the following steps: based on the sixth logical relationship between pedal force and pedal travel, simulate the braking of the vehicle to obtain the third relationship simulation curve corresponding to the sixth logical relationship; based on the third relationship simulation curve, adjust the initial elastic coefficient to obtain the preset elastic coefficient.

[0201] In the embodiments of this application, the device for determining the braking system parameters can establish a logical relationship between pedal force and pedal travel based on the above formula (11).

[0202] In the embodiments of this application, after establishing the logical relationship between pedal force and pedal travel, the braking deceleration determination device simulates the vehicle's braking based on the sixth logical relationship between pedal force and pedal travel, obtaining a third relationship simulation curve corresponding to the sixth logical relationship. An exemplary third relationship simulation curve is shown below. Figure 16 As shown, the graph presents the logical relationship between pedal force and pedal travel (161). The horizontal axis represents pedal travel in mm, and the vertical axis represents pedal force in N. This graph is generated by the simulator of the electronic brake pedal to show the relationship between pedal travel and pedal force. This graph is used to evaluate whether the pedal force corresponding to the pedal travel meets the requirements of pedal feel. It is compared with other graphs to evaluate whether the design of the two inflection points (162 and 163) is reasonable. When all evaluations meet the requirements, this graph will become one of the parameter inputs and performance target requirements for the electronic pedal design. All data lines must fall within the interval of the double-dotted line (164 and 165). Figure 16 It's a three-stage design with three different K values. Adjusting the K value changes the slope. Meanwhile, Figure 15 The positions of the two inflection points 153 and 154 in the text are related to... Figure 16 Corresponding to the 163 inflection point, it is also used to evaluate whether the design of the 163 inflection point position is reasonable. When Figure 15 The two inflection points (153 and 154) are below the dotted line at position 1.2, causing the brakes to fail to lock, which is unsafe and requires adjustment. Figure 16 The inflection point of 163 points shifted later. Figure 15 The two inflection points (153 and 154) will move upwards until they are above the dashed line to meet the performance requirements.

[0203] Therefore, by introducing a model relating pedal force to pedal travel and performing simulation analysis, the design of the pedal simulator becomes more scientific and reasonable. This effectively improves the smoothness of pedal force changes with travel, avoiding abrupt changes in force during driving and enhancing driving comfort. Furthermore, by adjusting the elastic coefficient, the pedal simulator can better match the dynamic characteristics of the vehicle's braking system, thereby improving the consistency and stability of overall braking performance.

[0204] In some embodiments, the initial drive motor energy recovery parameters include the initial axle energy recovery coefficient; the braking deceleration determination device may further perform the following steps: based on the axle energy recovery coefficient, establish a seventh logical relationship between the pedal travel and the torque generated by the axle drive motor energy recovery; the axle is the front axle or rear axle of the vehicle; based on the seventh logical relationship, simulate the vehicle's braking to obtain the fourth relationship simulation curve corresponding to the seventh logical relationship; based on the fourth relationship simulation curve, adjust the initial axle energy recovery coefficient to obtain the preset drive motor energy recovery parameters.

[0205] In the embodiments of this application, the braking deceleration determination device establishes a seventh logical relationship between the pedal travel and the torque generated by the energy recovery of the axle drive motor based on the above formula (9), and simulates the braking of the vehicle based on the seventh logical relationship to obtain the fourth relationship simulation curve corresponding to the seventh logical relationship. For example, see the fourth relationship simulation curve 171. Figure 17 As shown, the horizontal axis represents pedal travel (mm), and the vertical axis represents the torque generated by the energy recovery motor of the axle drive motor (N·m). This torque is the torque generated on the front or rear drive axle of the vehicle when the drive motor performs energy recovery under the control of the main controller program. Figure 13 Together, evaluate the rationality of the main controller's energy recovery control program parameter design. When all evaluations meet the requirements and design intent, this chart also serves as the design input for the main controller's energy recovery control program parameter design and provides a reference for vehicle calibration. This chart itself has no evaluation index requirements; adjusting n1 and n2 will change its behavior. Figure 13 and Figure 14 It will also change, and whether its design is reasonable needs to be considered jointly. Figure 13 and Figure 14 Does it meet the requirements?

[0206] Thus, by modeling the energy recovery system separately for the front or rear axle and conducting simulation analysis in conjunction with pedal travel, the energy recovery strategy becomes more flexible and controllable. This allows for optimization of the energy recovery path for vehicles with different drive layouts, improving energy utilization during braking; furthermore, by continuously adjusting the energy recovery coefficient through simulation feedback, the system can improve the overall vehicle's energy efficiency and range while ensuring braking performance.

[0207] In some embodiments, the braking deceleration determination device may further perform the following steps: establishing an eighth logical relationship between front wheel braking stiffness and total front wheel braking force based on a front wheel braking stiffness algorithm; establishing a ninth logical relationship between the clamping force of the caliper assembly corresponding to the front wheel of the vehicle and the braking force at the first wheel end based on preset braking system braking parameters; establishing a tenth logical relationship between front wheel braking stiffness and the clamping force of the caliper assembly corresponding to the front wheel of the vehicle based on the eighth and ninth logical relationships; simulating the braking of the vehicle based on the tenth logical relationship to obtain the fifth relationship simulation curve corresponding to the tenth logical relationship, and determining the caliper specification corresponding to the front wheel based on the fifth relationship simulation curve.

[0208] In the embodiments of this application, the braking deceleration determination device establishes the tenth logical relationship between the front wheel braking stiffness and the clamping force of the brake assembly caliper corresponding to the front wheel of the vehicle based on the above formulas (2) and (8), and then performs simulation to obtain the fifth relationship simulation curve, as shown in the figure. Figure 18 The figure shows the relationship curves between the tire-road adhesion coefficient (front wheel braking stiffness) and the brake assembly caliper clamping force when the front wheels lock up at 70% efficiency. The horizontal axis z represents the tire-road adhesion coefficient, and the vertical axis represents the brake assembly caliper clamping force (in N). Curve 181 shows the relationship curve corresponding to the clamping force of the front brake assembly caliper under no-load conditions; curve 182 shows the relationship curve corresponding to the clamping force of the brake assembly caliper under full load conditions. According to... Figure 18 Selecting the maximum permissible clamping force of the front caliper in an electronic caliper selection can assess whether the clamping capacity of the chosen caliper meets design requirements. The criterion is: the clamping force corresponding to position 1.2 in the chart must not exceed the maximum clamping force of the electronic caliper; otherwise, a larger caliper needs to be selected. The maximum clamping force of the electronic caliper and the braking deceleration can be directly obtained from the equipment.

[0209] Thus, by introducing a model relating front wheel braking stiffness to caliper clamping force and combining it with simulation analysis, the selection of front wheel calipers becomes more precise. This ensures, on the one hand, that the front wheels provide sufficient braking force under various braking conditions, avoiding brake failure or excessive wear caused by inappropriate caliper specifications; on the other hand, by continuously optimizing caliper selection through simulation feedback, the braking system can minimize hardware costs while meeting safety requirements, thereby improving the product's economic efficiency and competitiveness.

[0210] In some embodiments, the braking deceleration determination device may further perform the following steps: establishing an eleventh logical relationship between the rear wheel braking stiffness and the total rear wheel braking force; establishing a twelfth logical relationship between the clamping force of the brake assembly caliper corresponding to the rear wheel of the vehicle and the braking force at the first wheel end based on preset braking system braking parameters; establishing a thirteenth logical relationship between the rear wheel braking stiffness and the clamping force of the brake assembly caliper corresponding to the rear wheel of the vehicle based on the eleventh and twelfth logical relationships; simulating the braking of the vehicle based on the thirteenth logical relationship to obtain the sixth relationship simulation curve corresponding to the thirteenth logical relationship, and determining the caliper specification corresponding to the rear wheel based on the sixth relationship simulation curve.

[0211] In the embodiments of this application, the braking deceleration determination device establishes the tenth logical relationship between the front wheel braking stiffness and the clamping force of the brake assembly caliper corresponding to the front wheel of the vehicle based on the above formulas (2) and (8), and then performs simulation to obtain the fifth relationship simulation curve, as shown in the figure. Figure 18 The figure shows the relationship curves between the tire-road adhesion coefficient (front wheel braking stiffness) and the brake assembly caliper clamping force when the front wheels lock up at 70% efficiency. The horizontal axis z represents the tire-road adhesion coefficient, and the vertical axis represents the brake assembly caliper clamping force (in N). Curve 181 shows the relationship curve corresponding to the clamping force of the front brake assembly caliper under no-load conditions; curve 182 shows the relationship curve corresponding to the clamping force of the brake assembly caliper under full load conditions. According to... Figure 18 Selecting the maximum permissible clamping force of the front caliper in an electronic caliper selection can assess whether the clamping capacity of the selected front electronic caliper meets the design requirements. The judgment criteria are: Figure 18 When the horizontal axis z is 1.2, the clamping force of the brake assembly caliper on the vertical axis must not exceed the maximum clamping force of the electronic caliper; otherwise, a larger electronic caliper needs to be selected. The maximum clamping force of the electronic caliper and the braking deceleration can be directly obtained from the equipment.

[0212] Thus, by introducing a model relating rear wheel braking stiffness to caliper clamping force and combining it with simulation analysis, the selection of rear wheel calipers can also be based on scientific evidence. This ensures, on the one hand, that the rear wheels can provide stable braking force under different braking conditions, avoiding braking imbalance or loss of control caused by inappropriate caliper specifications; on the other hand, by continuously optimizing caliper selection through simulation feedback, the braking system can minimize hardware costs while meeting safety requirements, thereby improving the product's economy and competitiveness.

[0213] In some embodiments, the braking deceleration determination device may further perform the following steps: establishing a fourteenth logical relationship between the front wheel braking stiffness and the front wheel dynamic axle load, and establishing a fifteenth logical relationship between the front wheel dynamic axle load and the rear wheel dynamic axle load based on the total load of the vehicle; establishing a sixteenth logical relationship between the rear wheel dynamic axle load and the rear wheel braking stiffness, and establishing a seventeenth logical relationship between the front wheel braking stiffness and the rear wheel braking stiffness based on the fourteenth, fifteenth, and sixteenth logical relationships; simulating the vehicle braking based on the seventeenth logical relationship to obtain the seventh relationship simulation curve corresponding to the seventeenth logical relationship; and adjusting the initial braking system parameters and the initial drive motor energy recovery parameters based on the seventh relationship simulation curve to obtain the preset braking system braking parameters and the preset drive motor energy recovery parameters.

[0214] In the embodiments of this application, a fourteenth logical relationship is established between the front wheel braking stiffness and the front wheel dynamic axle load. For example, the fourteenth logical relationship is shown in formula (13):

[0215]

[0216] Where, N f denoted as the dynamic axle load of the front wheel, and z as the braking stiffness of the front wheel.

[0217] In the embodiments of this application, a fifteenth logical relationship between the dynamic axle load of the rear wheels and the dynamic axle load of the front wheels is established based on the total load of the vehicle. For example, the fifteenth logical relationship is shown in formula (14):

[0218] N r =MN f (14);

[0219] Where, N r This refers to the dynamic axle load of the rear wheels.

[0220] In the embodiments of this application, a sixteenth logical relationship is established between the total braking force of the front and rear wheels with energy recovery and the braking stiffness of the front and rear wheels. For example, the sixteenth logical relationship is shown in formula (15):

[0221]

[0222] Among them, Z r Z represents the rear wheel braking stiffness corresponding to the target total rear wheel braking force. r1 Z represents the rear wheel braking stiffness corresponding to the total braking force of the first rear wheel. 2r Z represents the rear wheel braking stiffness corresponding to the total braking force of the second rear wheel. f This refers to the front wheel braking stiffness corresponding to the total braking force of the front wheels.

[0223] In the embodiments of this application, such asFigure 20 As shown, curves 201, 202, and 203 represent the relationship between the braking stiffness of the front and rear wheels under no-load and rear wheel under full-load conditions, respectively. Intersection points 204 and 205 represent the synchronous adhesion coefficients under no-load and full-load conditions, respectively. The synchronous adhesion coefficients in this graph can be used to assess the rationality of the front and rear brake configuration. If the value at intersection point 204 is less than 0.6, it indicates that the front wheel braking force is too small or the rear wheel braking force is too large, making it prone to skidding in the event of ABS failure. If point 205 is greater than 1.2, it generally indicates that the front wheel braking force is too large or the rear wheel braking force is too small, making it difficult for the rear wheels to lock up and resulting in low utilization of the road adhesion coefficient.

[0224] Traditional algorithms require continuous data on the road surface adhesion coefficient as input. They obtain the braking stiffness of the front and rear wheels through a series of algorithms, then create a graph with braking stiffness on the x-axis and road surface adhesion coefficient on the y-axis. This approach results in both the continuous pedal travel (S) and the continuous road surface adhesion coefficient being used as inputs, but these two are not functionally related and cannot be correlated, making it impossible to program an automatic algorithm. The embodiments of this application, based on a braking stiffness algorithm, do not require the road surface adhesion coefficient as input. Instead, the front wheel braking stiffness is used as the y-axis, and the rear wheel braking stiffness as the x-axis; the intersection point represents the synchronous adhesion coefficient.

[0225] In the embodiments of this application, the receiving Figure 11 After obtaining the front wheel braking stiffness 1112 in step S1108, as follows Figure 11 As shown, the following steps S1112 and S1113 can also be performed:

[0226] Step S1112: Determine the dynamic axle loads of the front and rear wheels.

[0227] Here, based on the above formulas (13) and (14), the front wheel dynamic axle load 1114 and the rear wheel dynamic axle load 1115 can be determined.

[0228] Step S1113: Determine the braking stiffness.

[0229] Here, based on the above formula (15), the braking stiffness 1116 is determined: Z r Z r1 Z 2r Z f .

[0230] Thus, by introducing a model relating the dynamic axle load and braking stiffness of the front and rear wheels, and combining it with simulation analysis, the braking system achieves more balanced performance in energy recovery mode. This ensures, on the one hand, a more rational distribution of braking force between the front and rear wheels during energy recovery, avoiding vehicle instability caused by uneven energy recovery; on the other hand, continuous optimization of the brake assembly and energy recovery parameters through simulation feedback ensures the system maintains good braking response and energy recovery efficiency under different driving scenarios, thereby improving the overall vehicle intelligence and user experience.

[0231] In the embodiments of this application, when Figure 13 to Figure 20 After all braking process data is generated by algorithms and programs, conditional programs can be used to identify the specific performance results of feature points, making it easier for non-professionals or senior engineers who are not familiar with braking systems to understand and evaluate braking performance and braking capacity. Examples of evaluation items and results are shown in Table 1:

[0232] Table 1

[0233] Serial number Evaluation item Result 1 Front wheel lock-up clamping force (road surface u = 1.2, two people load, AK-unom) 38960 2 Rear wheel lock-up clamping force (road surface u = 1.2, two people load, AK-unom) 11854 3 Front wheel lock-up clamping force (road surface u = 1.2, full load, AK-unom) 41200 4 Rear wheel lock-up clamping force (road surface u = 1.2, full load, AK-unom) 16900 5 Front wheel lock-up clamping force (road surface u = 1.2, two people load, 70% degradation) 55600 6 Rear wheel lock-up clamping force (road surface u = 1.2, two people load, 70% degradation) 16934 7 Front wheel lock-up clamping force (road surface u = 1.2, full load, 70% degradation) 58800 8 Rear wheel lock-up clamping force (road surface u = 1.2, full load, 70% degradation6) 24122 9 Front wheel lock-up clamping force (road surface u = 1, two people load, AK-unom) 30680 10 Rear wheel lock-up clamping force (road surface u = 1, two people load, AK-unom) 11739 11 Front wheel lock-up clamping force (road surface u = 1, full load, AK-unom) 32480 12 Rear wheel lock-up clamping force (road surface u = 1, full load, AK-unom) 16420 13 Front wheel lock-up clamping force (road surface u = 1, two people load, 70% degradation) 43600 14 Rear wheel lock-up clamping force (road surface u = 1, two people load, 70% degradation) 16751 15 Front wheel lock-up clamping force (road surface u = 1, full load, 70% degradation) 46000 16 Rear wheel lock-up clamping force (road surface u = 1, full load, 70% degradation) 23400 17 Clamping force required for 20% slope + 10% (full load, 70% degradation) 15456 18 Clamping force required for 25% slope (full load, A 70% degradation) 17351 19 Clamping force required for 30% slope (full load, AK-unom) 15721

[0234] Here, AK-μnom refers to the general performance of the electronic caliper, and u is the road adhesion coefficient.

[0235] In the embodiments of this application, braking parameters K1, K2, K3, K4, n1, n2, etc., are introduced to parameterize the braking force and torque output relationship based on pedal travel S, determined by motor input / output characteristics, transmission efficiency, and motor driver program, thus enabling theoretical calculations and analyses. The braking force generated by energy recovery is incorporated into the entire braking force calculation, with a series of pedal travel S data used as input to establish the entire logical algorithm. All algorithms are correlated with pedal travel S, and the developed matching analysis tool is highly intelligent, fully correlated, and corresponding, facilitating matching and analysis.

[0236] Thus, the relationship between pedal force F, pedal travel S, and braking deceleration a was established. Simultaneously, the loading parameters (preset braking system braking parameters and preset drive motor energy recovery parameters) corresponding to the main controller's loading program for the drive motor and brake were introduced during parameter design. This described the different algorithms formed by the working principle of the electromechanical braking system, which differs from hydraulic and pneumatic braking systems. Through programming, a theoretical matching analysis tool for the electromechanical braking system can be obtained. Because this matching analysis tool not only incorporates traditional hardware parameters but also the braking force generated by energy recovery in new energy vehicles, and the associated parameters of the complete software control program related to braking performance, it can be used not only for comprehensive analysis of the braking performance and performance boundaries of the braking system during the design phase but also to provide reasonable calibration parameters for program calibration during actual vehicle matching calibration. It can analyze potential causes when braking performance problems occur and analyze feasible improvement solutions when braking performance needs to be improved, making its application very wide-ranging.

[0237] This application provides a method for determining braking deceleration. The method involves obtaining the pedal travel generated by the driver depressing the electronic brake pedal in the electromechanical braking system during vehicle braking. Using preset braking system parameters, based on the pedal travel, a first wheel-end braking force provided by the caliper clamping force of the vehicle's wheels is determined. Using preset drive motor energy recovery parameters, based on the pedal travel, a second wheel-end braking force provided by the torque generated by the drive motor's energy recovery is determined. Based on the first and second wheel-end braking forces corresponding to the front wheels, the total front-wheel braking force is determined. Under the function of the electronic brake-force distribution system, based on the total front-wheel braking force, a first rear-wheel total braking force is determined. Finally, based on the total front-wheel braking force and the first rear-wheel total braking force, the vehicle's braking deceleration is determined. This improves braking accuracy.

[0238] This application provides a braking deceleration determination device 210, such as... Figure 21 As shown, it includes:

[0239] The acquisition module 211 is used to acquire the pedal travel generated by the driver pressing the electronic brake pedal in the electromechanical braking system during the vehicle braking process.

[0240] The determining module 212 is used to determine the first wheel-end braking force provided by the clamping force of the brake assembly calipers of the vehicle's wheels based on the pedal travel using preset braking system braking parameters, and to determine the second wheel-end braking force provided by the torque generated by the energy recovery of the drive motor of the vehicle's wheels based on the pedal travel using preset drive motor energy recovery parameters.

[0241] The determination module 212 is also used to determine the total braking force of the front wheels based on the first wheel-end braking force and the second wheel-end braking force corresponding to the front wheels of the vehicle.

[0242] The determining module 212 is also used to determine the first rear wheel total braking force based on the total braking force of the front wheels when the vehicle is in the function of the electronic brake force distribution system, and to determine the vehicle's braking deceleration based on the total braking force of the front wheels and the first rear wheel total braking force.

[0243] In one embodiment of this application, the determining module 212 is further configured to determine the front wheel braking stiffness based on the total front wheel braking force, and determine the front wheel braking stiffness as the rear wheel braking stiffness; and determine the first rear wheel total braking force based on the rear wheel braking stiffness.

[0244] In one embodiment of this application, the determining module 212 is further configured to determine a first parameter based on the vehicle's gravity, center of gravity distance from the rear axle, and front and rear wheel track; and to determine a second parameter based on the vehicle's gravity, center of gravity height, and front and rear wheel track; to determine a third parameter based on the vehicle's gravity, total front wheel braking force, and front and rear wheel track; and to determine the front wheel braking stiffness based on the first, second, and third parameters.

[0245] In one embodiment of this application, the determining module 212 is further configured to determine a sixth parameter based on the vehicle's gravity, center of gravity distance from the front axle, front wheel braking stiffness, and front and rear wheel track; determine a seventh parameter based on the ratio of the vehicle's gravity, center of gravity height, rear wheel braking stiffness, and front and rear wheel track; and determine the total braking force of the first rear wheel based on the sixth and seventh parameters.

[0246] In one embodiment of this application, the determining module 212 is further configured to, when the vehicle is in the function of the anti-lock braking system, determine the second rear wheel total braking force based on the first wheel-end braking force and the second wheel-end braking force corresponding to the rear wheels of the vehicle; and determine the vehicle braking deceleration based on the front wheel total braking force and the second rear wheel total braking force.

[0247] In one embodiment of this application, the preset braking system braking parameters include the braking coefficient corresponding to the wheel of the vehicle; the determining module 212 is further configured to determine the product of the braking coefficient corresponding to the wheel and the pedal travel as the clamping force of the brake assembly caliper corresponding to the wheel for the wheel of the vehicle; and to determine the first wheel end braking force corresponding to the wheel based on the clamping force of the brake assembly caliper corresponding to the wheel and the corresponding wheel rotation ratio for the wheel of the vehicle.

[0248] In one embodiment of this application, the wheel rotation ratio includes the speed conversion factor and the wheel rolling radius corresponding to the wheel; the determining module 212 is further configured to determine the actual caliper clamping force corresponding to the wheel as the product of the brake assembly caliper clamping force corresponding to the wheel and the corresponding brake braking performance; determine the wheel rotation ratio corresponding to the wheel as the ratio of the speed conversion factor corresponding to the wheel and the corresponding wheel rolling radius; and determine the first wheel end braking force corresponding to the wheel as the product of the wheel rotation ratio corresponding to the wheel and the corresponding actual caliper clamping force.

[0249] In one embodiment of this application, the preset drive motor energy recovery parameters include the energy recovery braking coefficient corresponding to the vehicle's wheels; the determining module 212 is further configured to determine the torque generated by the drive motor energy recovery corresponding to the wheel based on the product of the energy recovery braking coefficient corresponding to the wheel and the pedal travel; and to determine the second wheel end braking force corresponding to the wheel as the ratio of the wheel's torque to the corresponding wheel rolling radius.

[0250] In one embodiment of this application, the determining module 212 is further configured to determine the sum of the first wheel-end braking force and the second wheel-end braking force corresponding to the front wheels of the vehicle as the total front wheel braking force; determine the sum of the first wheel-end braking force and the second wheel-end braking force corresponding to the rear wheels of the vehicle as the first rear wheel total braking force; determine the total wheel braking force based on the total front wheel braking force and the first rear wheel total braking force, and determine the ratio of the total wheel braking force to the total load of the vehicle as the braking deceleration.

[0251] In one embodiment of this application, the determining module 212 is further configured to: determine the front wheel braking stiffness based on the total front wheel braking force; determine the front wheel braking stiffness as the rear wheel braking stiffness of the vehicle; determine the second rear wheel total braking force based on the rear wheel braking stiffness; determine the target rear wheel total braking force from the first rear wheel total braking force and the second rear wheel total braking force; and determine the sum of the front wheel total braking force and the target rear wheel total braking force as the total wheel braking force.

[0252] In one embodiment of this application, the braking deceleration determination device 21 further includes a matching module (not shown in the figure), used to establish a first logical relationship between pedal travel and braking force at the first wheel end based on initial braking system braking parameters, and to establish a second logical relationship between pedal travel and braking force at the second wheel end based on initial drive motor energy recovery parameters; to establish a third logical relationship between pedal travel and vehicle braking deceleration based on the first and second logical relationships; to simulate vehicle braking based on the third logical relationship for different braking scenarios, and obtain a first relationship simulation curve corresponding to the third logical relationship; and to adjust the initial braking system braking parameters and the initial drive motor energy recovery parameters based on the first relationship simulation curve, and obtain preset braking system braking parameters and preset drive motor energy recovery parameters.

[0253] In one embodiment of this application, the matching module (not shown in the figure) is further configured to establish a fourth logical relationship between pedal force and pedal travel based on the initial elastic coefficient of the electronic brake pedal; establish a fifth logical relationship between pedal force and braking deceleration based on the fourth logical relationship; simulate vehicle braking based on the fifth logical relationship for different braking scenarios to obtain a second relationship simulation curve corresponding to the fifth logical relationship; and adjust the initial braking parameters based on the second relationship simulation curve to obtain preset braking parameters; wherein the initial braking parameters include at least one of the following: initial braking system braking parameters, initial drive motor energy recovery parameters, and initial elastic coefficient.

[0254] In one embodiment of this application, the matching module (not shown in the figure) is further used to simulate the braking of the vehicle based on the sixth logical relationship between the pedal force and the pedal travel, and obtain the third relationship simulation curve corresponding to the sixth logical relationship; based on the third relationship simulation curve, the initial elastic coefficient is adjusted to obtain the preset elastic coefficient.

[0255] In one embodiment of this application, the matching module (not shown in the figure) is further configured to establish a seventh logical relationship between the pedal travel and the torque generated by the energy recovery of the axle drive motor based on the axle energy recovery coefficient; the axle is the front axle or the rear axle of the vehicle; based on the seventh logical relationship, the braking of the vehicle is simulated to obtain the fourth relationship simulation curve corresponding to the seventh logical relationship; based on the fourth relationship simulation curve, the initial axle energy recovery coefficient is adjusted to obtain the preset drive motor energy recovery parameters.

[0256] In one embodiment of this application, the matching module (not shown in the figure) is further configured to establish an eighth logical relationship between the front wheel braking stiffness and the total front wheel braking force; establish a ninth logical relationship between the clamping force of the caliper assembly corresponding to the front wheel of the vehicle and the braking force at the first wheel end based on the preset braking system braking parameters; establish a tenth logical relationship between the front wheel braking stiffness and the clamping force of the caliper assembly corresponding to the front wheel of the vehicle based on the eighth and ninth logical relationships; simulate the braking of the vehicle based on the tenth logical relationship to obtain the fifth relationship simulation curve corresponding to the tenth logical relationship, and determine the caliper specification corresponding to the front wheel based on the fifth relationship simulation curve.

[0257] In one embodiment of this application, the matching module (not shown in the figure) is further configured to establish an eleventh logical relationship between the rear wheel braking stiffness and the total braking force of the rear wheels; establish a twelfth logical relationship between the clamping force of the brake assembly caliper corresponding to the rear wheel of the vehicle and the braking force at the first wheel end based on the preset braking system braking parameters; establish a thirteenth logical relationship between the rear wheel braking stiffness and the clamping force of the brake assembly caliper corresponding to the rear wheel of the vehicle based on the eleventh and twelfth logical relationships; simulate the braking of the vehicle based on the thirteenth logical relationship to obtain the sixth relationship simulation curve corresponding to the thirteenth logical relationship, and determine the caliper specification corresponding to the rear wheel based on the sixth relationship simulation curve.

[0258] In one embodiment of this application, the matching module (not shown in the figure) is further configured to establish a fourteenth logical relationship between the front wheel braking stiffness and the front wheel dynamic axle load, and based on the total load of the vehicle, establish a fifteenth logical relationship between the front wheel dynamic axle load and the rear wheel dynamic axle load; establish a sixteenth logical relationship between the rear wheel dynamic axle load and the rear wheel braking stiffness, and based on the fourteenth, fifteenth, and sixteenth logical relationships, establish a seventeenth logical relationship between the front wheel braking stiffness and the rear wheel braking stiffness; based on the seventeenth logical relationship, simulate the vehicle braking to obtain the seventh relationship simulation curve corresponding to the seventeenth logical relationship; based on the seventh relationship simulation curve, adjust the initial braking system braking parameters and the initial drive motor energy recovery parameters to obtain the preset braking system braking parameters and the preset drive motor energy recovery parameters.

[0259] This application provides a braking deceleration determination device that acquires the pedal travel generated by the driver depressing the electronic brake pedal in the electromechanical braking system during vehicle braking. Using preset braking system parameters, based on the pedal travel, it determines the first wheel-end braking force provided by the caliper clamping force of the vehicle's wheels. Using preset drive motor energy recovery parameters, based on the pedal travel, it determines the second wheel-end braking force provided by the torque generated by the energy recovery of the vehicle's drive motor. Based on the first and second wheel-end braking forces corresponding to the front wheels, it determines the total front wheel braking force. Under the function of the electronic brake force distribution system, based on the total front wheel braking force, it determines the first rear wheel total braking force, and based on the total front wheel braking force and the first rear wheel total braking force, it determines the vehicle's braking deceleration. This improves braking accuracy.

[0260] Figure 22 This is a schematic diagram of the structure of a braking deceleration determination device 220 provided in an embodiment of this application. In practical applications, based on the same disclosed concept of the above embodiments, such as... Figure 22 As shown, the braking deceleration determination device 220 in this embodiment includes: a processor 221, a memory 222, and a communication bus 223;

[0261] Communication bus 223 is used to realize the communication connection between processor 221 and memory 222;

[0262] Processor 221 is used to execute the computer program stored in memory 222 to implement the above-described method for determining braking deceleration.

[0263] This application provides a computer-readable storage medium storing a computer program thereon. The computer-readable storage medium stores one or more programs, which can be executed by one or more processors. The computer program implements the braking deceleration determination method as described above.

[0264] This application provides a computer program product, including a computer program or instructions. When the computer program or instructions are executed by processor 222, they implement the braking deceleration determination method as described above.

[0265] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of hardware embodiments, software embodiments, or embodiments combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0266] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0267] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0268] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0269] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A method for determining braking deceleration, characterized in that, The method includes: Acquire the pedal travel generated by the driver's depressing of the electronic brake pedal in the electromechanical braking system during vehicle braking; Using preset braking system braking parameters and based on the pedal travel, the first wheel-end braking force provided by the caliper clamping force of the vehicle's wheel brake assembly is determined, and using preset drive motor energy recovery parameters and based on the pedal travel, the second wheel-end braking force provided by the torque generated by the drive motor energy recovery of the vehicle's wheel is determined. The total braking force of the front wheels is determined based on the first wheel-end braking force and the second wheel-end braking force corresponding to the front wheels of the vehicle. When the vehicle is in the function of the electronic brake force distribution system, the first total braking force of the rear wheels is determined based on the total braking force of the front wheels, and the braking deceleration of the vehicle is determined based on the total braking force of the front wheels and the first total braking force of the rear wheels.

2. The method for determining braking deceleration according to claim 1, characterized in that, Determining the total braking force of the first rear wheel based on the total braking force of the front wheel includes: Based on the total braking force of the front wheels, the braking stiffness of the front wheels is determined, and the braking stiffness of the front wheels is then determined as the braking stiffness of the rear wheels. Based on the rear wheel braking stiffness, the total braking force of the first rear wheel is determined.

3. The method for determining braking deceleration according to claim 2, characterized in that, Determining the front wheel braking stiffness based on the total front wheel braking force includes: Based on the vehicle's gravity, center of gravity distance from the rear axle, and front and rear wheel track, a first parameter is determined, and based on the vehicle's gravity, center of gravity height, and front and rear wheel track, a second parameter is determined. The third parameter is determined based on the vehicle's gravity, the total braking force of the front wheels, and the track width between the front and rear wheels. Based on the first parameter, the second parameter, and the third parameter, the front wheel braking stiffness is determined.

4. The method for determining braking deceleration according to claim 2, characterized in that, The determination of the total braking force of the first rear wheel based on the rear wheel braking stiffness includes: The sixth parameter is determined based on the vehicle's gravity, center of gravity distance from the front axle, front wheel braking stiffness, and front and rear wheel track. The seventh parameter is determined based on the vehicle's gravity, center of gravity height, rear wheel braking stiffness, and the ratio of the front and rear wheel track widths. Based on the sixth parameter and the seventh parameter, the total braking force of the first rear wheel is determined.

5. The method for determining braking deceleration according to claim 1, characterized in that, The method further includes: When the vehicle is in the function of the anti-lock braking system, the total braking force of the second rear wheel is determined based on the braking force at the first wheel end and the braking force at the second wheel end corresponding to the rear wheel of the vehicle. The braking deceleration of the vehicle is determined based on the total braking force of the front wheels and the total braking force of the second rear wheels.

6. The method for determining braking deceleration according to claim 1, characterized in that, The preset braking system braking parameters include the braking coefficients corresponding to the vehicle's wheels; the determination of the first wheel-end braking force provided by the brake assembly caliper clamping force of the vehicle's wheels based on the pedal travel using the preset braking system braking parameters includes: For the wheels of the vehicle, the product of the braking coefficient corresponding to the wheel and the pedal travel is determined as the clamping force of the brake assembly caliper corresponding to the wheel. For the wheels of the vehicle, the first wheel-end braking force corresponding to the wheel is determined based on the clamping force of the brake assembly caliper corresponding to the wheel and the corresponding wheel rotation ratio.

7. The method for determining braking deceleration according to claim 6, characterized in that, The wheel rotation ratio includes the speed conversion factor and wheel rolling radius corresponding to the wheel; determining the first wheel-end braking force corresponding to the wheel based on the clamping force of the brake assembly caliper corresponding to the wheel and the corresponding wheel rotation ratio includes: The actual caliper clamping force corresponding to the wheel is determined by the product of the clamping force of the caliper of the brake assembly corresponding to the wheel and the braking efficiency of the corresponding brake. The ratio of the speed conversion factor corresponding to the wheel to the corresponding wheel rolling radius is determined as the wheel rotation ratio corresponding to the wheel. The product of the wheel rotation ratio corresponding to the wheel and the corresponding actual caliper clamping force is determined as the first wheel-end braking force corresponding to the wheel.

8. The method for determining braking deceleration according to claim 1, characterized in that, The preset drive motor energy recovery parameters include the energy recovery braking coefficients corresponding to the vehicle's wheels; the step of determining the second wheel-end braking force provided by the torque generated by the drive motor energy recovery of the vehicle's wheels based on the pedal travel using the preset drive motor energy recovery parameters includes: For the wheels of the vehicle, the torque generated by the energy recovery of the drive motor corresponding to the wheel is determined based on the product of the energy recovery braking coefficient corresponding to the wheel and the pedal travel. For the wheels of the vehicle, the ratio of the torque corresponding to the wheel to the rolling radius of the wheel is determined as the second wheel-end braking force corresponding to the wheel.

9. The method for determining braking deceleration according to any one of claims 1 to 8, characterized in that, The method further includes: Based on the initial braking system braking parameters, a first logical relationship is established between the pedal travel and the braking force at the first wheel end; and based on the initial drive motor energy recovery parameters, a second logical relationship is established between the pedal travel and the braking force at the second wheel end. Based on the first logical relationship and the second logical relationship, a third logical relationship is established between the pedal travel and the braking deceleration of the vehicle; For different braking scenarios, the braking of the vehicle is simulated based on the third logical relationship to obtain the simulation curve of the first relationship corresponding to the third logical relationship; Based on the first relationship simulation curve, the initial braking system braking parameters and the initial drive motor energy recovery parameters are adjusted to obtain the preset braking system braking parameters and the preset drive motor energy recovery parameters.

10. The method for determining braking deceleration according to claim 9, characterized in that, The method further includes: Based on the initial elastic coefficient of the electronic brake pedal, a fourth logical relationship between the pedal force and the pedal travel is established; Based on the fourth logical relationship, a fifth logical relationship is established between the pedal force and the braking deceleration. For different braking scenarios, the braking of the vehicle is simulated based on the fifth logical relationship to obtain the simulation curve of the second relationship corresponding to the fifth logical relationship; Based on the second relationship simulation curve, the initial braking parameters are adjusted to obtain the preset braking parameters; The initial braking parameters include at least one of the following: the initial braking system braking parameters, the initial drive motor energy recovery parameters, and the initial elastic coefficient.

11. The method for determining braking deceleration according to claim 10, characterized in that, After establishing the logical relationship between pedal force and pedal travel, the method further includes: Based on the sixth logical relationship between the pedal force and the pedal travel, the braking of the vehicle is simulated to obtain the simulation curve of the third relationship corresponding to the sixth logical relationship; Based on the simulation curve of the third relationship, the initial elastic coefficient is adjusted to obtain the preset elastic coefficient.

12. The method for determining braking deceleration according to claim 9, characterized in that, The initial drive motor energy recovery parameters include the initial axle energy recovery coefficient; the method further includes: Based on the axle energy recovery coefficient, a seventh logical relationship is established between the pedal travel and the torque generated by the energy recovery of the axle drive motor; the axle is the front axle or the rear axle of the vehicle. Based on the seventh logical relationship, the braking of the vehicle is simulated to obtain the simulation curve of the fourth relationship corresponding to the seventh logical relationship; Based on the fourth relationship simulation curve, the parameters of the initial axle energy recovery coefficient are adjusted to obtain the preset drive motor energy recovery parameters.

13. The method for determining braking deceleration according to claim 9, characterized in that, The method further includes: Establish the eighth logical relationship between the front wheel braking stiffness and the total braking force of the front wheels; Based on the preset braking system braking parameters, a ninth logical relationship is established between the clamping force of the caliper assembly corresponding to the front wheel of the vehicle and the braking force at the first wheel end. Based on the eighth and ninth logical relationships, a tenth logical relationship is established between the front wheel braking stiffness and the clamping force of the brake assembly caliper corresponding to the front wheel of the vehicle. Based on the tenth logical relation, the braking of the vehicle is simulated to obtain the fifth relation simulation curve corresponding to the tenth logical relation, and based on the fifth relation simulation curve, the caliper specification corresponding to the front wheel is determined.

14. The method for determining braking deceleration according to claim 9, characterized in that, The method further includes: Establish the eleventh logical relationship between the rear wheel braking stiffness and the total rear wheel braking force; Based on the preset braking system braking parameters, a twelfth logical relationship is established between the clamping force of the brake assembly caliper corresponding to the rear wheel of the vehicle and the braking force at the first wheel end. Based on the eleventh and twelfth logical relationships, a thirteenth logical relationship is established between the rear wheel braking stiffness and the clamping force of the brake assembly caliper corresponding to the rear wheel of the vehicle. Based on the thirteenth logical relationship, the braking of the vehicle is simulated to obtain the simulation curve of the sixth relationship corresponding to the thirteenth logical relationship. Based on the simulation curve of the sixth relationship, the caliper specification corresponding to the rear wheel is determined.

15. The method for determining braking deceleration according to claim 13 or 14, characterized in that, The method further includes: Establish the fourteenth logical relationship between the front wheel braking stiffness and the front wheel dynamic axle load, and establish the fifteenth logical relationship between the front wheel dynamic axle load and the rear wheel dynamic axle load based on the total load of the vehicle; Establish a sixteenth logical relationship between the rear wheel dynamic axle load and the rear wheel braking stiffness, and based on the fourteenth, fifteenth, and sixteenth logical relationships, establish a seventeenth logical relationship between the front wheel braking stiffness and the rear wheel braking stiffness; Based on the seventeenth logical relationship, the braking of the vehicle is simulated to obtain the simulation curve of the seventh relationship corresponding to the seventeenth logical relationship; Based on the seventh relationship simulation curve, the initial braking system braking parameters and the initial drive motor energy recovery parameters are adjusted to obtain the preset braking system braking parameters and the preset drive motor energy recovery parameters.

16. A device for determining braking deceleration, characterized in that, The device for determining the braking system parameters includes: The acquisition module is used to acquire the pedal travel generated by the driver pressing the electronic brake pedal in the electromechanical braking system during vehicle braking. The determination module is used to determine the first wheel-end braking force provided by the clamping force of the brake assembly calipers of the vehicle's wheels based on the pedal travel using preset braking system braking parameters, and to determine the second wheel-end braking force provided by the torque generated by the energy recovery of the drive motor of the vehicle's wheels based on the pedal travel using preset drive motor energy recovery parameters. The determining module is further configured to determine the total braking force of the front wheels based on the first wheel-end braking force and the second wheel-end braking force corresponding to the front wheels of the vehicle. The determining module is further configured to, under the function of the electronic brake force distribution system, determine the first total braking force of the rear wheels based on the total braking force of the front wheels, and determine the braking deceleration of the vehicle based on the total braking force of the front wheels and the first total braking force of the rear wheels.

17. A device for determining braking deceleration, characterized in that, The device for determining braking deceleration includes a processor, a memory, and a communication bus; when the processor executes the running program stored in the memory, it implements the method for determining braking deceleration as described in any one of claims 1 to 15.

18. A computer-readable storage medium, characterized in that, It stores a computer program that, when executed by a processor, implements the method for determining braking deceleration as described in any one of claims 1 to 15.

Images