A commercial vehicle safe following distance control method

Abstract

The application provides a commercial vehicle safe following distance control method, comprising the following steps: detecting the vehicle load before and after the vehicle starts and stops or when the vehicle moves at a constant speed, obtaining the vehicle load coefficient, and obtaining the road adhesion coefficient and road slope of the current vehicle driving; calculating the safe following distance of the vehicle according to the current vehicle load coefficient, the road adhesion coefficient and the road slope of the current vehicle driving, and the current vehicle speed; determining the following danger level based on the size relationship between the distance between the current vehicle and the front vehicle and the safe following distance; and formulating a corresponding active safe following protection strategy according to the following danger level. The safe following distance is calculated according to the current road conditions and various environmental factors of the vehicle, and the calculated safe following distance is not fixed and can be more accurate. In addition, the active safe following protection is performed on the vehicle, and the problem that there is no active safety function or the active safety measures are too single during the vehicle driving is solved.

Description

Technical Field

[0001] This invention relates to the field of vehicle control, and more specifically, to a method for controlling the safe following distance of commercial vehicles. Background Technology

[0002] Studies show that traffic accidents involving large trucks account for up to 70% of all traffic fatalities. Most accidents caused by vehicles failing to brake in time or driving too fast are related to commercial vehicles. This means that reducing the accident rate of trucks is a key factor in reducing traffic accidents, and it is particularly important to develop a strategy to control the safe following distance of trucks and implement proactive safety measures.

[0003] Previously, the safe following distance for vehicles was calculated at the factory setting by assuming numerous factors and setting a fixed value, or by testing and measuring the vehicle's maximum braking distance as the safe following distance. This did not take into account the impact of various reasonable changes that may occur in the actual use of commercial vehicles on the safe following distance. The current practice is as follows:

[0004] 1. Before a vehicle leaves the factory, its braking distance is measured at different speeds while driving it on a fixed test track and used as the safe following distance. However, a vehicle's braking distance is related to many factors, such as the road surface adhesion coefficient, driver reaction time, vehicle load, suspension system, tire pressure, and brake disc condition. Therefore, it is unreasonable to directly use the braking distance from the test track as the safe following distance.

[0005] 2. Adopt the most conservative safe following distance: With the vehicle fully loaded and traveling at maximum speed on the test track, brake as close to the maximum braking distance as possible, and use this braking distance as the safe following distance. This approach, to comply with national vehicle braking performance standards, requires limiting vehicle speed to shorten the braking distance. This means that even when the vehicle is unloaded or lightly loaded, it cannot travel at high speeds, hindering the vehicle's performance and negatively impacting the driver's experience.

[0006] 3. Currently, vehicles equipped with close following distance warning systems have overly simplistic warning strategies, only outputting either a safety or danger signal, and merely providing instrument panel alerts. This passive safety approach means that when drivers are not paying attention or are slow to react to the instrument panel, the safe following distance will be shortened, increasing the risk of accidents.

[0007] Braking distance of a vehicle while driving is related to many factors. Relying solely on the driver's experience, current speed, vehicle load, and visual estimation of the distance to the vehicle in front to control the following distance poses certain safety risks. Moreover, given the current situation of commercial vehicles carrying cargo in China, overloading is commonplace. Drivers often fail to consider that the braking distance of a vehicle will increase when it is fully loaded or overloaded. Therefore, calculating the safe following distance during vehicle operation is particularly important. Summary of the Invention

[0008] This invention addresses the technical problems existing in the prior art by providing a method for controlling the safe following distance of commercial vehicles, comprising:

[0009] The vehicle load is detected before and after the vehicle starts and stops or when the vehicle is moving at a constant speed. The vehicle load coefficient is obtained, as well as the road surface adhesion coefficient and road slope at which the vehicle is currently traveling.

[0010] The safe following distance is calculated based on the vehicle's current load coefficient, the road surface adhesion coefficient at which the vehicle is currently traveling, and the road gradient, combined with the vehicle's current speed.

[0011] The following hazard level is determined based on the relationship between the current distance between the vehicle and the vehicle in front and the safe following distance.

[0012] Develop corresponding proactive safety following protection strategies based on the aforementioned risk level of following vehicles.

[0013] Based on the above technical solution, the present invention can also be improved as follows.

[0014] Optionally, the step of detecting vehicle load before and after vehicle start-stop or when the vehicle is moving at a constant speed, obtaining the vehicle load coefficient, and obtaining the road surface adhesion coefficient and road slope of the vehicle's current travel includes:

[0015] When the vehicle speed is 0 or the vehicle is moving at a constant speed, the vehicle load is detected by the load sensor to obtain the vehicle load coefficient k.

[0016] The current weather conditions are obtained by using an atmospheric pressure sensor or an air humidity sensor, and the corresponding road surface adhesion coefficient μ is obtained based on the current weather conditions.

[0017] If the vehicle's current speed is greater than the set speed threshold, the slope α of the road the vehicle is currently traveling on is obtained through the slope sensor; otherwise, no action is taken.

[0018] The vehicle load coefficient k is adjusted according to the road slope α.

[0019] Optionally, adjusting the vehicle load coefficient k according to the road slope α includes:

[0020] ;

[0021] Where k' is the adjusted vehicle load coefficient.

[0022] Optionally, the step of calculating the safe following distance based on the vehicle's current load coefficient, the road surface adhesion coefficient at the vehicle's current speed, and the road gradient, combined with the vehicle's current speed, includes:

[0023] Based on the vehicle's current load coefficient k, the road surface adhesion coefficient μ, and the road slope α, combined with the vehicle's current speed v and the established functional relationship, the vehicle's braking distance s is calculated. 制动 ;

[0024] Calculate the safe distance between vehicles s=s 制动 +s 反应 , where s 反应 Driver reaction distance s 反应 =t 反应 v, safe following distance s0 = 1.1s.

[0025] Optionally, determining the following hazard level based on the relationship between the current vehicle's distance from the vehicle in front and the safe following distance includes:

[0026] Based on the aforementioned safe following distance, multiple distance ranges are set, and a corresponding following hazard level is configured for each distance range;

[0027] The current following hazard level of the vehicle is determined based on the distance range that the current vehicle falls into with the vehicle in front.

[0028] Optionally, determining the current following hazard level of the vehicle based on the distance range falling within the distance range between the current vehicle and the vehicle in front includes:

[0029] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 0;

[0030] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 1;

[0031] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 2;

[0032] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 3;

[0033] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 4;

[0034] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 5.

[0035] Optionally, a hysteresis interval can be set when the following hazard level of a vehicle changes each time it changes between two adjacent vehicles. ,in:

[0036] when The danger level of following another vehicle is set at 0. At that time, the danger level of following another vehicle jumps to 1. At that time, the danger level of following another vehicle will then jump to 0;

[0037] when At that time, the danger level of following another vehicle was set at 1. At that time, the danger level of following another vehicle jumps to 2. At that time, the danger level of following another vehicle will jump to 1;

[0038] when At that time, the danger level of following another vehicle was set at 2. At that time, the danger level of following another vehicle jumps to 3. At that time, the danger level of following another vehicle will jump to level 2;

[0039] when At that time, the danger level of following another vehicle was set at 3. At that time, the danger level of following another vehicle will jump to 4. At that time, the danger level of following another vehicle will jump to level 3;

[0040] when At that time, the danger level of following another vehicle was set at 4. At that time, the danger level of following another vehicle jumps to 5. At that time, the danger level of following another vehicle will jump to 4.

[0041] Optionally, based on the aforementioned following hazard level, a corresponding active safety following protection strategy can be formulated, including:

[0042] When the following hazard level of a vehicle is 0, no action is taken;

[0043] When the following hazard level of a vehicle is 1, the instrument panel will prompt the driver to maintain a following distance and control the vehicle speed.

[0044] When the following danger level of the vehicle is 2, the instrument panel will remind the driver that the following danger level is 2, and the vehicle acceleration will be limited by limiting the torque of the engine or drive motor.

[0045] When the following hazard level of the vehicle is 3, the instrument panel will prompt the driver that the following hazard level is 3 and send a signal to cut off the vehicle's drive.

[0046] When the following hazard level of the vehicle is 4, the instrument panel will remind the driver that the following hazard level is 4 and the vehicle will take active braking measures to reduce the speed.

[0047] When the following distance hazard level of a vehicle is 5, the instrument panel will display a warning to the driver that the following distance hazard level is 5, and the vehicle will be automatically braked.

[0048] Optionally, limiting vehicle acceleration by limiting the torque of the engine or drive motor includes:

[0049] The accelerator pedal fade-off depth is output based on the current distance between the vehicle and the vehicle in front:

[0050] when At that time, the accelerator pedal input should be 100% of the actual depth;

[0051] when At that time, the accelerator pedal decays to 50% of the actual input depth;

[0052] when When the accelerator pedal signal decays to 0, the accelerator pedal depth is reduced by a percentage between 1.6 and 1.4s0. When s1 = 1.4s0, the accelerator pedal depth is considered invalid.

[0053] When the following distance between the vehicle and the vehicle in front is When within the interval, according to The accelerator pedal depth is reduced by a percentage, limiting vehicle acceleration, and the accelerator pedal depth is considered invalid when the following hazard level is greater than or equal to 3.

[0054] Optionally, when the following hazard level of the vehicle is 4, the method of alerting the driver via the instrument panel that the following hazard level is 4 and taking active braking to reduce the vehicle speed includes:

[0055] When the following hazard level of the vehicle is 4, the instrument panel will notify the driver that the following hazard level is 4, and the simulated active braking depth will be defined based on the relationship between the current distance between the vehicle and the vehicle in front and the safe following distance.

[0056] when At that time, the simulated brake pedal depth is 0;

[0057] when At that time, the simulated brake pedal depth is 50%;

[0058] when When the simulated brake pedal depth is 100%, that is, the brake pedal is fully depressed, and the vehicle braking is controlled by ABS.

[0059] This invention provides a method for controlling the safe following distance of commercial vehicles. It calculates the safe following distance based on the current road conditions and various environmental factors, including the vehicle load coefficient, the current road surface adhesion coefficient, the road slope, the current vehicle speed, and the vehicle braking performance. The calculated safe following distance is not fixed and is more accurate. It also provides active safety following protection for the vehicle, solving the problem of vehicles lacking active safety functions or having overly simplistic active safety measures. Attached Figure Description

[0060] Figure 1 A flowchart of a method for controlling safe following distance in commercial vehicles provided by the present invention;

[0061] Figure 2 A schematic diagram illustrating the overall process of a method for controlling safe following distance in commercial vehicles;

[0062] Figure 3 A schematic diagram of the structure of a vehicle controller provided by the present invention;

[0063] Figure 4 A schematic diagram of a commercial vehicle safe following distance control system provided by the present invention;

[0064] Figure 5 A schematic diagram of a possible hardware structure of an electronic device provided by the present invention;

[0065] Figure 6 This is a schematic diagram of the hardware structure of a possible computer-readable storage medium provided by the present invention. Detailed Implementation

[0066] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention. In addition, the technical features of the various embodiments or individual embodiments provided by the present invention can be arbitrarily combined with each other to form feasible technical solutions. Such combinations are not constrained by the order of steps and / or structural composition patterns, but must be based on the ability of those skilled in the art to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0067] Figure 1 A flowchart of a method for controlling safe following distance in commercial vehicles provided by this invention can be found here. Figure 1 and Figure 2 Methods for controlling safe following distance include:

[0068] S1 detects vehicle load before and after vehicle start-stop or when vehicle is moving at a constant speed, obtains vehicle load coefficient, and obtains road surface adhesion coefficient and road slope of the current vehicle travel.

[0069] As an example, the step of detecting vehicle load before and after vehicle start-stop or when the vehicle is moving at a constant speed, obtaining the vehicle load coefficient, and obtaining the road surface adhesion coefficient and road slope of the vehicle's current travel includes: detecting vehicle load through a load sensor and obtaining the vehicle load coefficient k when the vehicle speed is 0 or the vehicle is moving at a constant speed; obtaining the current weather conditions through an atmospheric pressure sensor or an air humidity sensor, and obtaining the corresponding road surface adhesion coefficient μ according to the current weather conditions; if the current vehicle speed is greater than a set speed threshold, obtaining the road slope α of the vehicle's current travel through a slope sensor; otherwise, no processing is performed; and adjusting the vehicle load coefficient k according to the road slope α.

[0070] It is understood that in this embodiment of the invention, the safe following distance of the vehicle is calculated based on various environmental factors such as the current load of the vehicle, the road surface adhesion coefficient, the slope of the road, and traffic congestion. Therefore, when the various environmental factors of the vehicle's current driving change, the safe following distance of the vehicle also changes. Thus, the safe following distance of the vehicle calculated based on different environmental factors is more accurate.

[0071] Specifically, the vehicle load coefficient k is obtained by detecting the vehicle load when the vehicle speed is 0 and when the vehicle is moving at a constant speed. The current load of the vehicle is obtained through pressure sensors (load sensors) on the vehicle suspension. The value of k is defined by the factory-approved load capacity of the commercial vehicle. When the vehicle is unloaded, k is defined as 0; when the load is at the factory-approved load capacity, k is defined as 1. That is, k values ​​are used to represent the percentage of vehicle load (for example, k=0.5 is considered as half of the factory-approved load). Of course, considering that commercial vehicles may be overloaded, k values ​​greater than 1 are also considered valid and can be used for subsequent calculations. To prevent inaccurate load measurements due to vehicle bumps or starting on an incline from affecting the k value, the k value should be read before each vehicle start, during constant speed driving, or when the vehicle stops and starts at traffic lights.

[0072] Besides load and speed, the road surface adhesion coefficient is also a key factor affecting braking distance. For example, the road surface is more slippery in rainy weather, and the braking distance increases significantly in snowy weather. Therefore, estimating the current road surface adhesion coefficient μ can make the subsequent braking distance more accurate. Specifically, this can be achieved by installing an atmospheric pressure sensor or an air humidity sensor on the vehicle to estimate the current weather conditions and then comparing the results to obtain the corresponding road surface adhesion coefficient μ value. In snowy conditions, the driver needs to manually activate snow mode and limit the vehicle's maximum speed to ensure driver safety.

[0073] The braking distance of a vehicle when going uphill or downhill is very different from that when driving on flat ground. Therefore, it is also necessary to measure the road slope angle during the current driving to estimate the safe braking distance. When going uphill, the larger the road slope angle α, the shorter the braking distance will be. When going downhill, the larger the road slope angle α, the longer the braking distance will be.

[0074] To prevent inaccurate load measurement during vehicle start-up on an incline from affecting the k value, a slope sensor is introduced to measure the current road slope angle α. When α > 3°, the k' value is corrected. , The measured road slope.

[0075] S2 calculates the safe following distance of the vehicle based on the vehicle's current load coefficient, the road surface adhesion coefficient of the vehicle's current driving direction, and the road slope, combined with the vehicle's current speed.

[0076] As an example, the step of calculating the safe following distance of a vehicle based on the vehicle's current load coefficient, the road surface adhesion coefficient at which the vehicle is currently traveling, and the road slope, combined with the vehicle's current speed, includes: calculating the vehicle braking distance s based on the vehicle's current load coefficient k, the road surface adhesion coefficient μ at which the vehicle is currently traveling, and the road slope α, combined with the vehicle's current speed v and a set functional relationship. 制动 ; Calculate the safe distance between vehicles s=s 制动 +s 反应 , where s 反应 Driver reaction distance s 反应 =t 反应 v, safe following distance s0 = 1.1s.

[0077] Understandably, the braking distance is calculated by combining the vehicle load coefficient k, road surface adhesion coefficient μ, road slope angle α, current vehicle speed v, and vehicle braking performance. If the vehicle braking model is simplified to an ideal physical model, the vehicle will be in a locked-up state with sliding friction, and the braking distance will be unrelated to the vehicle's mass. This is clearly inconsistent with reality. Furthermore, during braking, especially under heavy loads, the front suspension experiences a greater load than the rear suspension due to inertia. With heavy loads, the front suspension will be excessively compressed, while the rear suspension will experience some lifting. This leads to a significant discrepancy between the theoretical calculation and the actual result. Moreover, during emergency braking with an ABS anti-lock braking system, the vehicle will not lock up its wheels, meaning the wheels will not continuously slide against the ground. The frictional force from the ground to the wheels will constantly change, further complicating the braking distance calculation. Therefore, this strategy uses a lookup table method to estimate the braking distance.

[0078] When a vehicle leaves the factory, it undergoes braking tests at a test track under different loads (k), speeds (v), road surface adhesion coefficients (μ), and road slope angles (α). By collecting a large amount of test data, a curve relating the braking distance to the vehicle load (k), road surface adhesion coefficient (μ), road slope angle (α), and pre-braking speed (v) can be fitted. Therefore, in subsequent practical applications, only the vehicle load (k), road surface adhesion coefficient (μ), road slope angle (α), and vehicle speed are needed to deduce the braking distance (s). 制动 .

[0079] In actual driving, the safe following distance is not exactly equal to the vehicle's braking distance, but rather the vehicle's braking distance plus the driver's reaction distance s. 反应 =t 反应 ×v. The safe following distance is:

[0080] s=s 制动 +s 反应 The unit is meters (m). However, the safe following distance generally needs to be defined as s0 = 1.1s to allow space between the vehicle and the vehicle in front.

[0081] S3, determine the following hazard level based on the relationship between the current distance between the vehicle and the vehicle in front and the safe following distance.

[0082] As an example, determining the following hazard level based on the relationship between the current vehicle's distance from the vehicle in front and the safe following distance includes: setting multiple distance intervals based on the safe following distance, configuring a corresponding following hazard level for each distance interval; and determining the current following hazard level of the vehicle based on the distance interval into which the current vehicle's distance from the vehicle in front falls.

[0083] Understandably, during driving, the vehicle monitors the following distance to the vehicle in front in real time, and determines the following hazard level of the vehicle based on the relationship between the following distance to the vehicle in front and the safe following distance.

[0084] The system reads real-time information about the distance between the vehicle and the vehicle in front from the onboard radar, comparing the actual following distance s1 with the safe following distance s0 obtained from a lookup table. To achieve active safety features, the danger level of following distance is divided into 6 levels:

[0085] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 0;

[0086] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 1;

[0087] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 2;

[0088] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 3;

[0089] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 4;

[0090] If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 5.

[0091] When performing a level transition, if the current defined relationship between s1 and s0 is strictly followed, the hazard level may switch back and forth between the two levels as the vehicle speed and following distance change. The vehicle will then switch back and forth between the two operations, but the response of the operation will have a certain delay, which may lead to a malfunction. Therefore, a hysteresis interval (which can be calibrated to 0.05s0) needs to be added for each level transition.

[0092] Based on this consideration, a hysteresis interval is set for when two adjacent vehicle hazard levels change each time the vehicle's following hazard level changes. ,in:

[0093] when The danger level of following another vehicle is set at 0. At that time, the danger level of following another vehicle jumps to 1. At that time, the danger level of following another vehicle will then jump to 0;

[0094] when At that time, the danger level of following another vehicle was set at 1. At that time, the danger level of following another vehicle jumps to 2. At that time, the danger level of following another vehicle will jump to 1;

[0095] when At that time, the danger level of following another vehicle was set at 2. At that time, the danger level of following another vehicle jumps to 3. At that time, the danger level of following another vehicle will jump to level 2;

[0096] when At that time, the danger level of following another vehicle was set at 3. At that time, the danger level of following another vehicle will jump to 4. At that time, the danger level of following another vehicle will jump to level 3;

[0097] when At that time, the danger level of following another vehicle was set at 4. At that time, the danger level of following another vehicle jumps to 5. At that time, the danger level of following another vehicle will jump to 4.

[0098] S4. Develop corresponding active safety following protection strategies based on the aforementioned following hazard level.

[0099] Understandably, the following hazard level of a vehicle is determined based on the relationship between the following distance and the safe following distance. Subsequently, corresponding active safety following protection strategies are formulated based on the following hazard level of the vehicle.

[0100] As an example, a corresponding active safety following protection strategy is formulated based on the following hazard level, including: when the following hazard level is 0, no measures are taken; when the following hazard level is 1, the driver is prompted by the instrument panel to maintain a following distance and control the vehicle speed; when the following hazard level is 2, the driver is prompted by the instrument panel to maintain a following hazard level of 2, and the vehicle acceleration is limited by limiting the torque of the engine or drive motor; when the following hazard level is 3, the driver is prompted by the instrument panel to maintain a following hazard level of 3, and a signal is sent to cut off the vehicle's drive; when the following hazard level is 4, the driver is prompted by the instrument panel to maintain a following hazard level of 4, and active braking is applied to reduce the vehicle speed; when the following hazard level is 5, the driver is prompted by the instrument panel to maintain a following distance hazard level of 5, and the vehicle is actively subjected to emergency braking.

[0101] Understandably, depending on the level of hazard of each following vehicle, the following measures must be taken:

[0102] ① Following distance danger level 0: Following too far away, no action is taken.

[0103] ② Following distance danger level 1: The following distance is too far. The instrument panel indicates that the following distance danger level is level 1. Please maintain an appropriate following distance and control your speed. The alarm will only be deactivated when the danger level reaches level 0.

[0104] ③ Following distance danger level 2: The following distance is slightly too close. The instrument panel indicates that the following distance danger level is level 2, limiting the torque of the engine or drive motor, which means limiting the vehicle's acceleration. The accelerator pedal wear-off depth can be adjusted according to the current following distance. The accelerator pedal is still input at 100% of the actual depth. The accelerator pedal decays to 50% of the actual input depth. When the accelerator pedal signal decays to 0, the accelerator pedal depth is reduced by a percentage between 1.6 and 1.4 seconds. That is, at 1.4 seconds, no matter how deeply the accelerator pedal is pressed, it is considered ineffective. Following distance is... Within the range, the depth of the accelerator pedal is reduced by a percentage to limit vehicle acceleration, and the accelerator pedal depth is considered invalid when the danger level is greater than or equal to 3.

[0105] ④ Following distance danger level 3: The following distance is too close. The instrument panel indicates that the following distance danger level is level 3. It is necessary to send a signal to cut off the vehicle's drive and let the vehicle enter the simulated neutral state to coast.

[0106] ⑤ Following distance danger level 4: The following distance is too close. The instrument panel indicates that the following distance danger level is level 4, and active braking is required to reduce the vehicle speed. The depth of simulated active braking is defined by the relationship between the following distance and the safe following distance. Simulated brake pedal depth is 0. Simulated brake pedal depth is 50%. When the simulated brake pedal depth is 100%, it is equivalent to fully depressing the brake pedal, and the vehicle braking is controlled by ABS.

[0107] ⑥ Following distance danger level 5: Extreme following distance. The instrument panel indicates to the driver that the following distance danger level is level 5, and the vehicle will be actively braked.

[0108] It should be noted that if the safe following distance control method provided by this invention is still executed when the vehicle is traveling at low speed, the vehicle may not be able to provide power or may misjudge the braking when the truck turns or stops at a narrow intersection, which will affect the driver's driving experience. Moreover, it will not cause a major traffic accident when the vehicle speed is low. Therefore, this control method strategy is defined to be executed only when the vehicle speed is greater than 30km / h (the specific vehicle speed can be defined by the user).

[0109] When a vehicle is in different following hazard levels and safety protection measures are implemented, the corresponding measures of the lower levels will be implemented simultaneously when the measures of the higher level are implemented. For example, when following hazard level 4, the braking signal will be output, the vehicle drive will be cut off, the accelerator pedal signal will be regarded as invalid and the instrument alarm will be triggered at the same time. (The hazard level does not need to be strictly implemented according to the values ​​of s1 and s0 in this invention. The specific level needs to be determined by actual test, debugging and calibration.)

[0110] See Figure 3 This invention provides a vehicle controller that implements a method for controlling the safe following distance of a vehicle. The vehicle controller includes an acquisition module 301, a calculation module 302, a determination module 303, and a setting module 304, wherein:

[0111] The acquisition module 301 is used to detect vehicle load before and after vehicle start-stop or when vehicle is moving at a constant speed, acquire vehicle load coefficient, and acquire road surface adhesion coefficient and road slope of the vehicle currently traveling.

[0112] The calculation module 302 is used to calculate the safe following distance of the vehicle based on the current load coefficient of the vehicle, the road surface adhesion coefficient of the vehicle at its current speed, and the road slope, combined with the current vehicle speed.

[0113] The determining module 303 is used to determine the following hazard level based on the relationship between the current distance between the vehicle and the vehicle in front and the safe following distance;

[0114] The module 304 is used to formulate corresponding active safety following protection strategies based on the following hazard level.

[0115] It is understood that the vehicle controller provided by the present invention corresponds to the commercial vehicle safe following distance control method provided in the foregoing embodiments. The relevant technical features of the vehicle controller can be referred to the relevant technical features of the commercial vehicle safe following distance control method, and will not be repeated here.

[0116] See Figure 4 The present invention provides a safe following distance control system for commercial vehicles, including various sensors, vehicle controllers, instruments, motor controllers and braking systems. The various sensors include slope sensors, humidity sensors, wheel speed sensors, load sensors, vehicle radar, etc.

[0117] Among them, the slope sensor senses the slope of the road the vehicle is currently traveling on, the humidity sensor detects the road surface adhesion coefficient, the wheel speed sensor detects the real-time vehicle speed, the load sensor detects the vehicle load and obtains the vehicle load coefficient, and the on-board radar detects the following distance between the vehicle and the vehicle in front.

[0118] Various sensors send detected data to the vehicle controller, which calculates the safe following distance based on this data. It then determines the vehicle's following hazard level by comparing the current following distance to the vehicle in front with the safe following distance. Based on this hazard level, the controller adjusts the instrument cluster, motor controller, and braking system to provide active safety protection for the vehicle.

[0119] Please see Figure 5 , Figure 5 This is a schematic diagram illustrating an embodiment of the electronic device provided in this invention. For example... Figure 5 As shown, this embodiment of the invention provides an electronic device 500, including a memory 510, a processor 520, and a computer program 511 stored in the memory 510 and executable on the processor 520. When the processor 520 executes the computer program 511, it performs the following steps: detecting vehicle load before and after vehicle start-stop or when the vehicle is moving at a constant speed, obtaining the vehicle load coefficient, and obtaining the road surface adhesion coefficient and road slope of the vehicle's current driving position; calculating the safe following distance of the vehicle based on the current vehicle load coefficient, the current road surface adhesion coefficient, and the road slope, combined with the vehicle's current speed; determining the following hazard level based on the relationship between the current distance between the vehicle and the vehicle in front and the safe following distance; and formulating a corresponding active safety following protection strategy based on the following hazard level.

[0120] Please see Figure 6 , Figure 6 This is a schematic diagram illustrating an embodiment of a computer-readable storage medium provided by the present invention. (See diagram below.) Figure 6 As shown, this embodiment provides a computer-readable storage medium 600, on which a computer program 611 is stored. When the computer program 611 is executed by a processor, it performs the following steps: detecting vehicle load before and after vehicle start-stop or when vehicle is moving at a constant speed, obtaining vehicle load coefficient, and obtaining the road surface adhesion coefficient and road slope of the vehicle's current travel; calculating the safe following distance of the vehicle based on the current vehicle load coefficient, the current road surface adhesion coefficient, and the road slope, combined with the vehicle's current speed; determining the following hazard level based on the relationship between the current distance between the vehicle and the vehicle in front and the safe following distance; and formulating a corresponding active safety following protection strategy based on the following hazard level.

[0121] The following method for controlling safe following distance of commercial vehicles provided in this invention has the following advantages:

[0122] (1) Detect vehicle load, road slope, and road surface adhesion coefficient, and calculate vehicle braking distance by combining current vehicle speed and load coefficient. The calculated safe distance is more accurate and has stronger real-time performance.

[0123] (2) The following mode is determined by vehicle radar and estimated safe distance, making the implementation of the plan more diverse;

[0124] (3) By comparing the real-time radar detection value with the estimated following distance, proactive safety protection actions are taken;

[0125] (4) Provide instrument prompts, limit vehicle speed, limit torque and speed, cut off vehicle power, and perform active emergency braking according to different levels.

[0126] It should be noted that the descriptions of each embodiment in the above embodiments have different focuses. For parts that are not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0127] 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 a completely hardware embodiment, a completely software embodiment, or an embodiment 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, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0128] 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 computer, 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. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0129] 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.

[0130] 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.

[0131] Although preferred embodiments of the invention have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including both the preferred embodiments and all changes and modifications falling within the scope of the invention.

[0132] Obviously, those skilled in the art can make various modifications and variations to this invention without departing from its spirit and scope. Therefore, if these modifications and variations fall within the scope of the claims of this invention and their equivalents, this invention also intends to include these modifications and variations.

Claims

1. A method for controlling the safe following distance of a commercial vehicle, characterized in that, include: The vehicle load is detected before and after the vehicle starts and stops or when the vehicle is moving at a constant speed. The vehicle load coefficient is obtained, as well as the road surface adhesion coefficient and road slope at which the vehicle is currently traveling. The safe following distance is calculated based on the vehicle's current load coefficient, the road surface adhesion coefficient, and the road gradient, combined with the vehicle's current speed. ; Based on the current distance between the vehicle and the vehicle in front With respect to the safe following distance The size relationship determines the following hazard level, which includes 1, 2 and 3; Develop corresponding proactive safety following protection strategies based on the aforementioned risk level of following vehicles; Among them, the corresponding active safety following protection strategy is formulated according to the aforementioned following hazard level, including: When the following hazard level of a vehicle is 2, the instrument panel will alert the driver that the following hazard level is 2, and the vehicle's acceleration will be limited by restricting the torque of the engine or drive motor. Specifically: The accelerator pedal fade-off depth is output based on the current distance between the vehicle and the vehicle in front: when At that time, the accelerator pedal input should be 100% of the actual depth; when At that time, the accelerator pedal decays to 50% of the actual input depth; when When the accelerator pedal signal decays to 0, the accelerator pedal depth is reduced by a percentage between 1.6 and 1.4s0. When s1 = 1.4s0, the accelerator pedal depth is considered invalid. When the following distance between the vehicle and the vehicle in front is When within the interval, according to The accelerator pedal depth is reduced by a percentage, limiting vehicle acceleration, and the accelerator pedal depth is considered invalid when the following hazard level is greater than or equal to 3.

2. The safe following distance control method according to claim 1, characterized in that, The process of detecting vehicle load before and after vehicle start-stop or during constant speed movement, obtaining the vehicle load coefficient, and obtaining the road surface adhesion coefficient and road gradient of the vehicle's current travel includes: When the vehicle speed is 0 or the vehicle is moving at a constant speed, the vehicle load is detected by the load sensor to obtain the vehicle load coefficient k. The current weather conditions are obtained by using an atmospheric pressure sensor or an air humidity sensor, and the corresponding road surface adhesion coefficient μ is obtained based on the current weather conditions. If the vehicle's current speed is greater than the set speed threshold, the slope α of the road the vehicle is currently traveling on is obtained through the slope sensor; otherwise, no action is taken. The vehicle load coefficient k is adjusted according to the road slope α.

3. The safe following distance control method according to claim 2, characterized in that, Adjusting the vehicle load coefficient k according to the road slope α includes: ； Where k' is the adjusted vehicle load coefficient.

4. The safe following distance control method according to claim 1, characterized in that, The calculation of the safe following distance based on the vehicle's current load coefficient, the road surface adhesion coefficient, and the road gradient, combined with the vehicle's current speed, includes: Based on the vehicle's current load coefficient k, the road surface adhesion coefficient μ, and the road slope α, combined with the vehicle's current speed v and the established functional relationship, the vehicle's braking distance s is calculated. 制动 ; Calculate the safe distance between vehicles s=s 制动 +s 反应 , where s 反应 Driver reaction distance s 反应 =t 反应 v, safe following distance s0 = 1.1s.

5. The safe following distance control method according to claim 1 or 4, characterized in that, The method of determining the following hazard level based on the relationship between the current vehicle's distance from the vehicle in front and the safe following distance includes: Based on the aforementioned safe following distance, multiple distance ranges are set, and a corresponding following hazard level is configured for each distance range; The current following hazard level of the vehicle is determined based on the distance range that the current vehicle falls into with the vehicle in front.

6. The safe following distance control method according to claim 5, characterized in that, The determination of the current following hazard level of the vehicle based on the distance range falling within the distance between the current vehicle and the vehicle in front includes: If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 0; If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 1; If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 2; If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 3; If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 4; If the current vehicle is far from the vehicle in front If so, the current following hazard level of the vehicle is 5.

7. The safe following distance control method according to claim 6, characterized in that, Each time the following hazard level of a vehicle changes, a hysteresis interval is set for when the following hazard levels of two adjacent vehicles change. ,in: when The danger level of following another vehicle is set at 0. At that time, the danger level of following another vehicle jumps to 1. At that time, the danger level of following another vehicle will then jump to 0; when At that time, the danger level of following another vehicle was set at 1. At that time, the danger level of following another vehicle jumps to 2. At that time, the danger level of following another vehicle will jump to 1; when At that time, the danger level of following another vehicle was set at 2. At that time, the danger level of following another vehicle jumps to 3. At that time, the danger level of following another vehicle will jump to level 2; when At that time, the danger level of following another vehicle was set at 3. At that time, the danger level of following another vehicle will jump to 4. At that time, the danger level of following another vehicle will jump to level 3; when At that time, the danger level of following another vehicle was set at 4. At that time, the danger level of following another vehicle jumps to 5. At that time, the danger level of following another vehicle will jump to 4.

8. The safe following distance control method according to claim 1, characterized in that, Based on the aforementioned risk level of following another vehicle, corresponding active safety following protection strategies are developed, which also include: When the following hazard level of a vehicle is 0, no action is taken; When the following hazard level of a vehicle is 1, the instrument panel will prompt the driver to maintain a following distance and control the vehicle speed. When the following hazard level of the vehicle is 3, the instrument panel will prompt the driver that the following hazard level is 3 and send a signal to cut off the vehicle's drive. When the following hazard level of the vehicle is 4, the instrument panel will remind the driver that the following hazard level is 4 and the vehicle will take active braking measures to reduce the speed. When the following distance hazard level of a vehicle is 5, the instrument panel will display a warning to the driver that the following distance hazard level is 5, and the vehicle will be automatically braked.

9. The safe following distance control method according to claim 8, characterized in that, When the following hazard level of a vehicle is 4, the system will alert the driver via the instrument panel that the following hazard level is 4 and take active braking measures to reduce the vehicle speed, including: When the following hazard level of the vehicle is 4, the instrument panel will notify the driver that the following hazard level is 4, and the simulated active braking depth will be defined based on the relationship between the current distance between the vehicle and the vehicle in front and the safe following distance. when At that time, the simulated brake pedal depth is 0; when At that time, the simulated brake pedal depth is 50%; when When the simulated brake pedal depth is 100%, that is, the brake pedal is fully depressed, and the vehicle braking is controlled by ABS.

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