CN115743239A - Virtual marshalling train control method and system based on emergency braking rate dynamic configuration - Google Patents

Abstract

The invention discloses a virtual marshalling train control method and system based on dynamic configuration of emergency braking rates, and relates to the technical field of rail traffic signal safety protection. The steps of the method of the present invention are: determine the current running phase of the virtual train; any two adjacent trains in the virtual train are respectively the leading train and the following train, and dynamically modify the leading train and the following train according to the situation of the current running phase The emergency braking rate of the following vehicle. The present invention dynamically configures the emergency braking rate of the trains according to the relative positional relationship between the unit trains, thereby not only meeting the requirement of small-distance tracking of virtual marshalling unit trains, but also maximally avoiding the influence on the minimum interval distance of independently running trains.

Description

Control method and system for virtual marshalling train based on dynamic configuration of emergency braking rate

technical field

The invention relates to the technical field of rail transit signal safety protection, and more specifically relates to a control method and system for virtual marshalling trains based on dynamic configuration of emergency braking rates.

Background technique

With the rapid development of rail transit network construction, people's demand for its transportation capacity and operational flexibility is also increasing. In order to meet the above goals, virtual marshalling technology has received extensive attention at home and abroad, and has become a current research hotspot.

Train virtual marshalling technology refers to two trains with independent traction and braking capabilities, through wireless communication and active cooperative control between trains, to realize the technology of forming a marshalling train without relying on the coupling of physical couplers. The minimum separation distance between trains in the virtual formation unit is determined by the initial speed and braking capacity of the two cars. Since the speed of the two cars is required to be kept the same in the virtual marshalling mode, the minimum separation distance between unit trains is mainly determined by the braking capacity of the two cars. Due to the randomness in the train braking process, there is a certain error in the emergency braking rate. In order to ensure safety, the train safety protection control system needs to use the maximum value of the emergency braking rate of the leading car and the minimum value of the emergency braking rate of the following car when calculating the distance between trains (or protection speed). When they are consistent, the emergency braking rate used in the calculation of the following car will be smaller than that of the leading car, so that the distance between the two cars will be larger, and it is difficult to meet the requirement that the distance between virtual trains is close to that of physical trains.

In order to reduce the separation distance of unit trains as much as possible under the premise of safety, it is obvious that the emergency braking rate of the following vehicle should be as high as possible, and the emergency braking rate of the leading vehicle should be as small as possible. However, unit trains sometimes need to operate independently, and the roles of the leading train and the following train will be reversed when the train turns back. Therefore, if the emergency braking rate of the static train cannot meet the operation requirements of the virtual train at the same time, it is even more difficult to take into account the independence of the train. running requirements. Traditionally, the emergency braking rate of train vehicles is determined during vehicle design and checked and confirmed through parameter adjustment during vehicle type tests, and usually does not change during train operation. However, in fact, the expected emergency braking rate of the train is a parameter stored in the vehicle braking system, and the adjustment of the expected braking rate of the train can be realized by modifying this parameter when necessary

Therefore, for those skilled in the art, how to dynamically modify the emergency braking rate according to the change of the role of the train in the virtual train formation is an urgent problem to be solved.

Contents of the invention

In view of this, the present invention provides a virtual formation train control method and system based on the dynamic configuration of the emergency braking rate, and dynamically modifies the emergency braking rate according to the role change of the train in the virtual formation train, so as to meet the requirements of the virtual formation train. The demand for small interval tracking of unit trains can also avoid the impact on the minimum interval distance of independently running trains to the greatest extent.

In order to achieve the above object, the present invention adopts the following technical scheme: a virtual marshalling train control method based on emergency braking rate dynamic configuration, and the specific steps include the following:

determine the current stage of operation of the virtual train;

Any two adjacent trains in the virtual grouping train are respectively a lead car and a follower car, and the emergency braking rates of the lead car and the follower car are dynamically modified according to the situation in the current operation stage.

Optionally, dynamically modifying the emergency braking rates of the leading vehicle and the following vehicle according to the situation in the current operation stage specifically includes:

If the virtual formation train is in the formation formation stage, the vehicle-to-vehicle communication is established between the leading vehicle and the following vehicle and information is periodically exchanged, and the braking rate of the leading vehicle is reduced under the premise of confirming safety , the braking rate of the following car becomes larger, that is, the emergency braking rate of the leading car is changed from the default gear to the second gear, and the emergency braking rate of the following car is changed from the default gear to the first gear ;

If the virtual marshalling train is in the decomposing stage, modify the emergency braking rate of the lead car from the second gear to the default gear, and the emergency braking rate of the following car from the first gear The bit is changed to the default file.

Optionally, the first gear is the maximum braking rate that the train emergency braking system can provide, and the second gear is the minimum braking rate that the train emergency braking system can provide.

Optionally, the on-board controller judges the relationship between the actual distance between the leading vehicle and the following vehicle and the required minimum separation distance before the braking rate changes and the required minimum separation distance after the change, and The timing of modifying the configuration value of the emergency braking rate of the train is controlled, so as to ensure the driving safety.

Optionally, a safe way to increase the braking rate of the following car is:

S1, the following car sends a message that the emergency braking rate of the train is expected to increase to the following car; the following car calculates the EBI speed according to the modified braking rate of the following car and protects the train from running safely;

S2. When the following vehicle determines that the emergency braking will not be triggered, send a parking guarantee message to the following vehicle;

S3. The following car receives the parking guarantee information, modifies the emergency braking rate configuration state, and calculates the EBI speed according to the modified braking rate.

Optionally, the safe way to make the braking rate of the leading car smaller is:

S1. The lead car calculates the EBI speed according to the modified braking rate. If emergency braking is not triggered, the leading car controls the vehicle to modify the configuration state of the emergency braking rate;

S2. The leading vehicle sends the modified emergency braking rate configuration state to the following vehicle, so that the following vehicle calculates the EBI speed.

On the other hand, there is provided a virtual formation train control system based on emergency braking rate dynamic configuration, including a vehicle-to-vehicle communication module, a first vehicle-mounted controller, and a second vehicle-mounted controller; wherein,

The vehicle-to-vehicle communication module is used to determine the current running stage of the virtual train;

The first vehicle-mounted controller is installed on the leading vehicle, and the second vehicle-mounted controller is installed on the following vehicle, and is used to dynamically modify the emergency braking of the leading vehicle and the following vehicle according to the situation in the current operation stage. dynamic rate.

It can be seen from the above-mentioned technical solutions that, compared with the prior art, the present invention discloses a method and system for controlling virtual marshalling trains based on dynamic configuration of emergency braking rate, which has the following beneficial technical effects:

(1) Break through the limitation of the traditional train control system based on the constant emergency braking rate of the train for protection control, and design a method and system for dynamic configuration of the emergency braking rate of the train combined with the running state of the virtual marshalling train;

(2) It stipulates the modification timing of the configuration value of the emergency braking rate of the train and the safety principles that should be followed, and gives the selection method of the configuration value of the emergency braking rate of the own vehicle and the emergency braking rate of the preceding vehicle when calculating EBI;

(3) When forming a virtual formation, the emergency braking rate of the leading car can be changed to "low gear", and the emergency braking rate of the following car can be changed to "high gear", so as to compensate the calculation protection caused by the error of the emergency braking rate of the train The problem that the braking rate of the following car used at speed is smaller than the braking rate of the leading car, shorten the tracking interval of the virtual formation train; when exiting the virtual formation (turning to independent operation), restore the emergency braking rate of the two cars to "default" according to the specified rules Gear", so that the train interval is consistent with other trains without braking rate configuration, and avoid the impact of the modification of the virtual train braking rate on the normal train operation. .

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only It is an embodiment of the present invention, and those skilled in the art can also obtain other drawings according to the provided drawings without creative work.

Fig. 1 is method flowchart of the present invention;

Fig. 2 is the train relation schematic diagram of the present invention;

Fig. 3 is a safety sequence requirement diagram when the braking rate of the following vehicle changes from "default gear" to "high gear" according to the present invention;

Fig. 4 is the safety sequence requirement diagram when the braking rate of the leading car of the present invention changes from "default gear" to "low gear";

Fig. 5 is the schematic flow chart of the emergency braking rate configuration value flow chart of the vehicle used when determining and calculating the EBI speed of the present invention;

Fig. 6 is the schematic flow chart of the preceding vehicle emergency braking rate configuration value used when determining and calculating the EBI speed of the present invention;

Fig. 7 is a system structure diagram of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

The embodiment of the present invention discloses a virtual marshalling train control method based on dynamic configuration of emergency braking rate, as shown in Figure 1, the specific steps include the following:

determine the current stage of operation of the virtual train;

Any two adjacent trains in the virtual marshalling train are the lead car and the follower car respectively, and the emergency braking rates of the lead car and the follower car are dynamically modified according to the situation of the current operation stage.

Further, dynamically modifying the emergency braking rates of the leading vehicle and the following vehicle according to the situation in the current operation stage specifically includes:

If the virtual marshalling train is in the marshalling formation stage, the leading car and the following car establish vehicle-to-vehicle communication and periodically exchange information. On the premise of confirming safety, the braking rate of the leading car becomes smaller and the braking rate of the following car becomes smaller. Large, that is, change the emergency braking rate of the leading car from the default gear to the second gear, and change the emergency braking rate of the following car from the default gear to the first gear;

If the virtual marshalling train is in the decomposing stage, the emergency braking rate of the leading car is changed from the second gear to the default gear, and the emergency braking rate of the following train is changed from the first gear to the default gear.

It should be noted that the first gear is the maximum braking rate that the train emergency braking system can provide, that is, the high gear; the second gear is the minimum braking rate that the train emergency braking system can provide, that is, the low gear; the default gear is the braking rate of the emergency braking system of the train under normal conditions, which is consistent with the braking rate of ordinary trains.

The virtual marshalling train operation scenarios can be divided into four scenarios: "independent operation", "marshalling formation", "marshalling operation" and "marshalling unmarshalling". The principle of the present invention will be further described below in conjunction with the running conditions of each scene. Since two unit trains, the leading car and the following car, are involved in the conversion of the virtual marshalling scene, and there may be other trains before and after them, the change of the emergency braking rate of the train may involve up to four trains. For ease of description, Figure 2 shows the front and rear positional relationships and names among the four trains.

When in "independent operation" or "formation operation", the emergency braking rate of the train does not need to change. At this time, VOBC should calculate the minimum safety distance according to the actual braking rate of the train, and monitor the relationship between the actual distance of the train and the minimum safety distance, and implement emergency braking when necessary.

In the process of "forming formation", the emergency braking rate of the following car is changed from "default gear" to "high gear" and the emergency braking rate of the leading car is changed from "default gear" to "low gear".

Specifically, the safety sequence requirements when the braking rate of the following car changes from "default gear" to "high gear" are shown in Figure 3:

1) The following car provides "stop guarantee" information for the increased braking rate of the following car: the following car sends a message about the expected increase in the emergency braking rate of the train to the following car; the following car calculates EBI based on the modified braking rate of the following car speed and protect the safe operation of the train (this information is required if the following vehicle adopts the protection model of "hitting a soft wall"; if the following vehicle adopts the protection model of "hitting a hard wall", this information is no longer needed, which is equivalent to passing the direct inspection of this condition ); when the following car confirms that the emergency brake will not be triggered, it will send a "stop guarantee" message to the following car;

2) Follow the car to control the vehicle to modify the configuration status of the emergency braking rate;

3) The VOBC of the following vehicle calculates the EBI speed according to the modified braking rate and protects the train from running safely.

Specifically, the safety timing requirements when the leading car’s braking rate changes from “default gear” to “low gear” are shown in Figure 4:

1) The leading car VOBC provides the "stop guarantee" information for the reduction of its own braking rate: the leading car calculates the EBI speed according to the modified braking rate of the car. If it does not trigger emergency braking, it is equivalent to having the "stopping guarantee" information. Guarantee" information, start to calculate the EBI speed and protect the safe operation of the train;

2) The lead vehicle controls the vehicle to modify the emergency braking rate configuration status;

3) The leading car sends the modified emergency braking rate configuration status to the following car for use when the following car calculates the EBI speed.

Further, the change of the configuration value of the emergency braking rate of the train will lead to the change of the minimum separation distance. On the basis of the above, judge the relationship between the actual distance between the two vehicles and the minimum separation distance required before and after the change of the braking rate, and determine the timing of modifying the configuration value of the emergency braking rate of the train control to ensure driving safety. The specific rules are:

The modification of the train emergency braking rate configuration value can be divided into two categories, which are: making the "braking rate larger" (including changing from "low gear" to "default gear" and from "default gear" to "high gear" " and from "low gear" to "high gear") and make the "braking rate smaller" (including from "high gear" to "default gear", from "default gear" to "low gear" and from "High gear" is changed to "low gear"). In the following, according to this classification, the control methods for modifying the timing of the configuration value of the emergency braking rate of the train will be described respectively.

When intending to modify the configuration value of the emergency braking rate to make the vehicle's emergency "braking rate larger", it should be executed according to the following safety sequence:

It should be noted that the own car refers to the following car in the formation process of formation and the leading car in the process of unmarshalling.

Step 1: The car confirms that modifying the configuration value of the emergency braking rate will not put the car behind in a dangerous situation;

Step 2: Modify the actual emergency braking rate configuration value of the vehicle to the increased value (the specific process is: VOBC sends a braking rate configuration value modification command to the vehicle braking system, and the vehicle braking system receives the command and modifies the configuration parameters , send the updated train braking rate configuration value to VOBC after the parameter modification is successful);

Step 3: Finally modify the emergency braking rate parameter of the own vehicle used when calculating the EBI speed by the VOBC of the own vehicle to an increased value (updated value received from the braking system of the own vehicle).

Among them, in step 1, the vehicle confirms that modifying the emergency braking rate configuration value will not put the rear vehicle in a dangerous situation can be divided into the following situations:

(1) There is no following car behind the car that is tracked using the principle of hitting a soft wall:

At this time, modifying the emergency braking rate of this vehicle will not affect the minimum separation distance of the following vehicles, and this article is directly satisfied;

(2) There is a rear car tracked by the soft wall tracking principle behind the car:

At this time, the car needs to confirm through the vehicle-to-vehicle communication that the car can stop safely. That is, the emergency braking rate parameter of the vehicle used to calculate the EBI speed after modification is an increased value, and the actual distance between the two vehicles is guaranteed to be greater than the minimum separation distance required after modification. The specific implementation method is:

1) The vehicle sends the message "the emergency braking rate of the vehicle is about to increase" to the vehicle behind (including the current braking rate configuration value and the braking rate configuration value to be modified);

2) The rear vehicle calculates EBI according to the configuration value of the emergency braking rate to be modified by the vehicle, and judges whether it will cause the rear vehicle to output EB, which may be divided into the following two situations:

a) If the following vehicle does not need to output EB, send a message to the vehicle that "the emergency braking rate of this vehicle increases without affecting the safe operation of the vehicle behind (referred to as parking guarantee)", and keep calculating the EBI speed of the vehicle behind and Implementation of overspeed protection;

b) If the following car needs to output EB, then send the message "It is impossible to guarantee that the car will stop safely after the emergency braking rate becomes larger" to the car, and keep calculating the EBI speed and Implement overspeed protection (to avoid unnecessary emergency braking), but the ATO or driver of the following vehicle can control the train to decelerate until the actual distance between the two vehicles is large enough and condition a) is met, then send the parking guarantee information to the vehicle, and follow this Car modified emergency braking rate to calculate EBI speed and implement overspeed protection.

3) Before the vehicle receives the parking guarantee information of the following vehicle, it considers that the conditions required in step 1 have not been met.

Furthermore, combined with the principle of train safety protection control, it can be known that if the emergency "braking rate" of the train becomes smaller, the braking distance of the own vehicle will increase, so that the required distance between the vehicle and the vehicle in front will increase, but the rear The required separation distance between the car and the own car becomes smaller. Still based on the relationship between the trains shown in Figure 2, the rules for modifying the configured value of the emergency braking rate of the train in this mode will be described.

The steps to execute the safety sequence when intending to make the "braking rate smaller" are as follows:

Step 1: First confirm that the distance between the vehicle and the vehicle in front is large enough;

Step 2: Modify the actual emergency braking rate configuration value of the vehicle to the reduced value (the specific process is: VOBC sends a braking rate configuration value modification command to the vehicle braking system, and the vehicle braking system receives the command and modifies the configuration parameters , send the updated train braking rate configuration value to VOBC after the parameter modification is successful);

Step 3: The emergency braking rate parameter of the vehicle used when calculating the EBI speed after the modified VOBC is the reduced value.

Among them, the way to confirm that the distance between the vehicle and the vehicle in front is sufficiently large in step 1 is: the vehicle first modifies the emergency braking rate of the vehicle used in calculating the EBI to a reduced value, and then judges whether to output emergency braking, Divided into two situations:

(1) The reduction of the emergency braking rate of the vehicle will not cause the train to output emergency braking (EB):

At this time, it is considered that the condition of step 1 is satisfied, and VOBC continues to calculate EBI speed and implement overspeed protection according to the modified (smaller) emergency braking rate.

(2) The reduction of the emergency braking rate of the vehicle will cause the train to output emergency braking:

At this time, it is considered that the conditions of step 1 are not met yet, and VOBC calculates EBI and implements overspeed protection according to the emergency braking rate before modification. The condition of step 1 is considered to be satisfied until the actual distance between the vehicle in front and the vehicle in front is large enough, and the modified emergency braking rate of the vehicle will not cause the train to output EB.

In addition, the design of step 3 is to allow the following vehicle to better track the own vehicle. In practical applications, if there is a rear car that hits a soft wall and is tracked, the emergency braking rate configuration value sent by the vehicle to the rear vehicle will be updated to the latest modified state, and the rear vehicle will follow the latest update after receiving the information. The state calculates the EBI of the following car and implements overspeed protection; if there is no following car that hits the soft wall at this time, this step is not involved.

In the train protection control scheme based on the principle of hitting a soft wall, the emergency braking rate of the own vehicle and the emergency braking rate of the preceding vehicle need to be used when calculating EBI. Combining with the design principle of modifying the emergency braking rate of the train above, it is proposed that the configuration value of the emergency braking rate of the vehicle used by VOBC to calculate EBI is shown in Figure 5, and the value of the emergency braking rate of the preceding vehicle used is shown in Figure 6 shown.

Figure 5. Combining the emergency braking rate configuration status of the vehicle and the expected emergency braking rate configuration value of the vehicle, determine the emergency braking rate configuration value that should be used when calculating the EBI speed of the vehicle, and determine that the rearward vehicle should The sent information such as "the configuration value of the emergency braking rate of the vehicle" and "the configuration method of the expected emergency braking rate of the vehicle".

Figure 6. Based on information such as whether the vehicle is tracking against a soft wall, the actual emergency braking rate configuration value of the preceding vehicle, and the expected emergency braking rate allocation method of the preceding vehicle, determine the value of the vehicle in front that should be used when calculating the EBI speed of the vehicle. Emergency braking rate configuration value, and determines whether to send a "stop guarantee" message to the vehicle ahead.

According to Figure 5 and Figure 6, after determining the emergency braking rate of the vehicle and the vehicle in front that should be used when calculating EBI, it is easy to calculate the EBI speed of the train according to the relevant formula and implement overspeed protection. Therefore, according to the content of the invention, the configuration value of the emergency braking rate of the relevant trains can be dynamically modified according to the running status of the virtual trains, so as to realize the small-distance tracking of the virtual trains without affecting the performance of the unit trains running independently.

Embodiment 2 of the present invention provides a virtual marshalling train control system based on dynamic configuration of emergency braking rate, as shown in FIG.

The vehicle-to-vehicle communication module is used to determine the current operation stage of the virtual formation train;

The first vehicle-mounted controller is installed on the leading vehicle, and the second vehicle-mounted controller is installed on the following vehicle, and is used for dynamically modifying the emergency braking rates of the leading vehicle and the following vehicle according to the situation of the current operation stage.

The VOBC on each unit train, according to its role in the virtual formation train, uses the vehicle-to-train communication to exchange information, and sends the correct emergency braking rate configuration command to each vehicle at an appropriate time, so as to realize the small distance in the virtual formation. trace without affecting system performance when running standalone.

Each embodiment in this specification is described in a progressive manner, each embodiment focuses on the difference from other embodiments, and the same and similar parts of each embodiment can be referred to each other. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and for the related information, please refer to the description of the method part.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (8)

1. a virtual formation train control method based on emergency braking rate dynamic configuration, it is characterized in that, concrete steps comprise as follows: determine the current stage of operation of the virtual train; Any two adjacent trains in the virtual grouping train are respectively a lead car and a follower car, and the emergency braking rates of the lead car and the follower car are dynamically modified according to the situation in the current operation stage. 2. A kind of virtual formation train control method based on dynamic configuration of emergency braking rate according to claim 1, characterized in that, according to the situation of the current operation stage, the emergency braking ratio of the leading car and the following car is dynamically modified. Specifically, the braking rate includes: If the virtual formation train is in the formation formation stage, the vehicle-to-vehicle communication is established between the leading vehicle and the following vehicle and information is periodically exchanged, and the braking rate of the leading vehicle is reduced under the premise of confirming safety , the braking rate of the following car becomes larger, that is, the emergency braking rate of the leading car is changed from the default gear to the second gear, and the emergency braking rate of the following car is changed from the default gear to the first gear ; If the virtual marshalling train is in the decomposing stage, modify the emergency braking rate of the leading car from the second gear to the default gear, and the emergency braking rate of the following car from the first gear The bit is changed to the default file. 3. a kind of virtual formation train control method based on emergency braking rate dynamic configuration according to claim 2, is characterized in that, described first stall is the maximum braking rate that train emergency braking system can provide, so The second gear is the minimum braking rate provided by the train emergency braking system. 4. a kind of virtual formation train control method based on emergency braking rate dynamic configuration according to claim 1, is characterized in that, the actual distance and braking rate of described lead car and described follower car are compared by on-board controller Judging the relationship between the minimum separation distance required before the change and the minimum separation distance required after the change, and controlling the timing of modifying the configuration value of the emergency braking rate of the train, so as to ensure driving safety. 5. a kind of virtual formation train control method based on emergency braking rate dynamic configuration according to claim 1, is characterized in that, the safety mode that makes the braking rate of described following car become larger is: S1, the following car sends a message that the emergency braking rate of the train is expected to increase to the following car; the following car calculates the EBI speed according to the modified braking rate of the following car and protects the train from running safely; S2. When the following vehicle determines that the emergency braking will not be triggered, send a parking guarantee message to the following vehicle; S3. The following car receives the parking guarantee information, modifies the emergency braking rate configuration state, and calculates the EBI speed according to the modified braking rate. 6. a kind of virtual formation train control method based on emergency braking rate dynamic configuration according to claim 1, is characterized in that, the safety mode that makes the braking rate of described leading car diminish is: S1. The lead car calculates the EBI speed according to the modified braking rate. If emergency braking is not triggered, the leading car controls the vehicle to modify the configuration state of the emergency braking rate; S2. The leading vehicle sends the modified emergency braking rate configuration state to the following vehicle, so that the following vehicle calculates the EBI speed. 7. A method for controlling virtual marshalling trains based on dynamic configuration of emergency braking rate according to claim 6, wherein the method for judging whether to trigger emergency braking is: the calculated EBI speed and the actual speed of the lead car For comparison, if the EBI speed is greater than the actual speed of the leading vehicle, emergency braking is triggered. 8. A virtual marshalling train control system based on dynamic configuration of emergency braking rate, characterized in that it includes a vehicle-to-vehicle communication module, a first vehicle-mounted controller, and a second vehicle-mounted controller; wherein, The vehicle-to-vehicle communication module is used to determine the current running stage of the virtual train; The first vehicle-mounted controller is installed on the leading vehicle, and the second vehicle-mounted controller is installed on the following vehicle, and is used to dynamically modify the emergency braking of the leading vehicle and the following vehicle according to the situation in the current operation stage. dynamic rate.

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