An emergency vehicle priority passing control method in a networked environment

Abstract

The application provides an emergency vehicle priority passing control method in a network environment, which can be applied to emergency vehicle priority passing in various density states, has little influence on traffic operation efficiency without lane changing of social vehicles, and can effectively guarantee the priority passing of emergency vehicles; including circumscribing two closest social vehicles in two lanes in front of the emergency vehicle, judging whether the social vehicles need to be guided for speed adjustment according to the head transverse distance and head-tail longitudinal distance of the two social vehicles, if needed, corresponding speed guidance is performed on the circumscribed social vehicles through the shortest adjustment time and adjustment speed obtained by calculation, and the emergency vehicle follows at low speed; if not needed, the emergency vehicle normally alarms to realize priority passing; finally, after the emergency vehicle passes through the two circumscribed social vehicles, the speed guidance is repeatedly judged again until the emergency vehicle drives away from the congested road section, and the shortest travel time of the emergency vehicle through the congested road section is obtained.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of vehicle passage control, in particular to an emergency vehicle priority passage control method in a networked environment. BACKGROUND

[0002] Emergency vehicle priority passage is of great importance to maintaining traffic order and protecting people's life and property safety. The existing priority passage control methods are path optimization, signal preemption and road section reservation. Path optimization refers to dynamically selecting the best route for the emergency vehicle during driving to obtain the shortest response time. Signal preemption is to adjust the signal light to make the emergency vehicle have priority passage. Road section reservation refers to guiding the social vehicles to change lanes in advance to provide a fast driving passage for the emergency vehicle. The first two methods are traditional research methods, and there are more research results. However, with the continuous development of V2X technology, vehicle interaction is becoming more and more frequent. With the help of road section reservation technology, multi-vehicle cooperative control is implemented, and road section reservation will become a research hotspot in recent years.

[0003] The road section reservation method can be divided into two categories according to the adjustment object: emergency vehicles and social vehicles. The adjustment of the emergency vehicle to achieve priority passage based on the road section reservation method is shown in Figure 1 , which includes the following three steps:

[0004] Step 1: The emergency vehicle detects the density of the front lane and determines the minimum density lane and judges whether it needs to change lanes.

[0005] Step 2: If it needs to change lanes, adjust the spacing of the social vehicles in the changed lane to make it sufficient for the emergency vehicle to change lanes. If it does not need to change lanes, it will drive normally.

[0006] Step 3: The emergency vehicle completes the lane change and drives for a period of time, then detects the density of the front lane again, and repeats Step 1.

[0007] The above method of adjusting the emergency vehicle to achieve priority passage reduces the delay of social vehicles to some extent, but frequent lane changing increases the braking and reaction time of the emergency vehicle, and does not consider the adjustment time of the social vehicles in the low-density lane to provide space for the emergency vehicle.

[0008] The adjustment of the social vehicle to achieve priority passage based on the road section reservation method is shown in Figure 2 , which includes the following three steps:

[0009] Step 1: The emergency vehicle sends a yielding warning to the social vehicles in the congested road section when it is a certain distance away from the congested road section.

[0010] Step 2: Calculate the adjustment speed of each vehicle by means of an algorithm and send it to the social vehicles.

[0011] Third step: after receiving the adjustment alarm and instruction, the social vehicle changes lane to the lane without emergency vehicle, and the emergency vehicle keeps the original speed to pass the road section;

[0012] The above-mentioned way of adjusting the social vehicle to realize priority passing, although the emergency vehicle is not affected, but how to obtain enough space in the lane during the lane changing process is a difficult problem, and the current research literature adopts two strategies, one is to assume that the space is sufficient, and the other is to control the speed of the vehicle in front to increase or decrease; Specifically, the deceleration strategy refers to the first social vehicle decelerating to give enough distance for the adjustment of the remaining social vehicles; The acceleration strategy refers to accelerating the vehicles in the vicinity or the entire road section to drive away from the area when an emergency vehicle enters, but the deceleration strategy will cause a large delay, and the acceleration strategy ignores the remaining space in the lane;

[0013] In summary, whether the adjustment object is an emergency vehicle or a social vehicle, there are two problems:

[0014] (1) Only applicable to congested road sections that can provide enough lane changing space (not too dense state);

[0015] (2) Lane changing has a large impact on traffic efficiency (unreasonable yielding method), and the travel time of the emergency vehicle through the congested road section cannot be predicted. SUMMARY

[0016] In view of the above problems, the present application provides an emergency vehicle priority passing control method in a network environment, which can be applied to emergency vehicle priority passing in various density states, and does not require social vehicle lane changing, has a small impact on traffic efficiency, and can effectively guarantee the priority passing of the emergency vehicle.

[0017] The present application adopts the following technical scheme, an emergency vehicle priority passing control method in a network environment, comprising the following steps:

[0018] S1, collecting the basic information of the congested road section in the communication area, including the lane width, the road section length, and determining the priority control area of the road section;

[0019] S2, circumscribing the two closest social vehicles in the two lanes in front of the emergency vehicle, and obtaining the head transverse distance and head-tail longitudinal distance of the two circumscribed social vehicles, then judging whether the social vehicle needs to be guided to adjust the speed according to the head transverse distance and the head-tail longitudinal distance, if needed, the shortest adjustment time and adjustment speed obtained by calculation are used to guide the corresponding speed of the circumscribed social vehicle, and in the adjustment process, the emergency vehicle follows at a low speed; If not, the emergency vehicle normally alarms to realize priority passing;

[0020] S3, after the adjustment is completed, the emergency vehicle resumes the original speed driving until passing the two social vehicles in the delineated area, and then repeats the step S2 again until the emergency vehicle drives off the congested road section and obtains the shortest travel time of the emergency vehicle passing the congested road section.

[0021] Further, in the step S2, if the speed adjustment of the two social vehicles in the delineated area is not needed, the emergency vehicle normally straight passes after guiding the social vehicles to drive on the side through the emergency vehicle's own alarm;

[0022] Further, in the step S2, if the speed adjustment of the two social vehicles in the delineated area is needed, the following steps are further included:

[0023] S2.1, based on the vehicle state, obtaining the position and speed information of the emergency vehicle and the social vehicle in the lane of the control area road section;

[0024] S2.2, constructing a double-target constraint model to make the head lateral distance and the head-tail longitudinal distance of the two social vehicles in the delineated area meet the passing requirements of the emergency vehicle;

[0025] S2.3, updating the position of the emergency vehicle and the social vehicle according to the vehicle state transition;

[0026] Further, in the step S2.2, the double-target constraint model composed of constraint equations (1)-(6) is constructed, that is:

[0027]

[0028] Wherein, Lgmin represents the minimum head lateral distance; L represents the head-tail longitudinal distance;

[0029] V min represents the lower limit of the adjusted speed of the social vehicle; V max represents the upper limit of the adjusted speed of the social vehicle;

[0030] min means minimization; J is the abbreviation of the objective function;

[0031] represents the speed of the social vehicle i in the left lane in front of the emergency vehicle at t+Δt k ;

[0032] represents the speed of the social vehicle j in the right lane in front of the emergency vehicle at t+Δt k ;

[0033] represents the position of the social vehicle i in the left lane in front of the emergency vehicle at t+Δt k ;

[0034] This indicates that a social vehicle j is located in the right lane in front of the emergency vehicle at time t+Δt. k The position at that moment;

[0035] This indicates that vehicle i+1 is located in the left lane in front of the emergency vehicle at time t+Δt. k The position at that moment;

[0036] This indicates that vehicle j+1, located in the right lane ahead of the emergency vehicle, is in the lane at time t+Δt. k Position at time; Δv i This represents the speed change of the i-th civilian vehicle in the left lane in front of the emergency vehicle during the adjustment process.

[0037] Δv j This represents the speed change of the j-th civilian vehicle in the right lane in front of the emergency vehicle during the adjustment process.

[0038] Δt k This represents the time of the k-th adjustment, where k ≥ 1;

[0039] Constraint (1) and constraint (2) indicate that the adjusted speed of social vehicles meets the upper and lower speed limits;

[0040] Constraint (3) indicates that when the adjustment of social vehicles is completed, the longitudinal spacing between the front and rear meets the requirements;

[0041] Constraint formulas (4) and (5) indicate that two civilian vehicles located in the left and right lanes in front of the emergency vehicle meet the minimum lateral distance requirement during the adjustment process;

[0042] Constraint (6) indicates that if there is no solution, the change in velocity Δv cannot be obtained. i , velocity change Δv j Then the time Δt will be adjusted. k Add a unit duration and substitute it into the objective function and constraints (1) to (5), calculate again, and if there is a solution, proceed to step S2.3 to update the positions of emergency vehicles and social vehicles;

[0043] Further, in step S2.3, the vehicle state transition calculation formula is:

[0044]

[0045] in, This indicates the position of vehicle i in the left lane in front of the emergency vehicle at time t;

[0046] denotes the position of the social vehicle j in the right lane in front of the emergency vehicle at time t;

[0047] denotes the speed of the social vehicle i in the left lane in front of the emergency vehicle at time t;

[0048] denotes the speed of the social vehicle j in the right lane in front of the emergency vehicle at time t;

[0049] y(t+1) denotes the position of the emergency vehicle at time t+1; y(t) denotes the position of the emergency vehicle at time t;

[0050] V E denotes the driving speed of the emergency vehicle;

[0051] Further, in the step S3, further comprising:

[0052] After the speed adjustment of the social vehicle is completed, the emergency vehicle resumes driving at the original speed for a unit time, and then the travel time of the emergency vehicle is updated as:

[0053] t = t + Δt k +1

[0054] Subsequently, the adjustment time Δt k , the speed change amount Δv i , and the speed change amount Δv j obtained by iteration through the double-target constraint model are substituted into the state transition equation y(t+1) of the emergency vehicle, and then it is judged whether the emergency vehicle has driven off the congestion road section;

[0055] Further, the judgment formula for the emergency vehicle driving off the congestion road section is y(t) ≥ l,

[0056] If the judgment formula is satisfied, it indicates that the emergency vehicle has driven off the congestion road section;

[0057] If the judgment formula is not satisfied, it indicates that the emergency vehicle has not driven off the congestion road section, and then the updated travel time value of the emergency vehicle is substituted into the double-target constraint model in step S2.2 to repeat the adjustment detection;

[0058] wherein l denotes the length of the congestion road section.

[0059] Further, when the judgment formula for the emergency vehicle driving off the congestion road section is satisfied, the shortest travel time of the emergency vehicle through the congestion road section is obtained according to the formula:

[0060] min t = arg[y(t)]

[0061]

[0062] wherein arg denotes the inverse function.​

[0063] The beneficial effects of the present application are that when the emergency vehicle needs to pass through the congested road section, the social vehicle does not need to change lanes, and the influence on the traffic operation efficiency is relatively small. The social vehicle can be guided to adjust the speed according to the head lateral distance and the head-tail longitudinal distance, so as to meet the requirements of the emergency vehicle passing through as soon as possible, effectively guarantee the priority of the emergency vehicle passing through, and predict the time of the emergency vehicle passing through the congested road section. The method can be applied to the priority of the emergency vehicle passing through under various density states, and has good practical value. BRIEF DESCRIPTION OF DRAWINGS

[0064] Figure 1 is a schematic diagram of adjusting the emergency vehicle to realize the priority of passing through based on the existing road section reservation;

[0065] Figure 2 is a schematic diagram of adjusting the social vehicle to realize the priority of passing through based on the existing road section reservation;

[0066] Figure 3 is a flowchart in the present application;

[0067] Figure 4 is a schematic diagram of the normal passing of the emergency vehicle in the present application;

[0068] Figure 5 is a schematic diagram of the social vehicle in the present application;

[0069] Figure 6 is a speed guiding diagram of the social vehicle in the present application;

[0070] Figure 7 is a schematic diagram of the detour of the emergency vehicle in the present application;

[0071] Figure 8 is a space-time diagram under the uneven density state in the embodiment of the present application;

[0072] Figure 9 is a relationship curve diagram between the initial distance of the social vehicle and the travel time of the emergency vehicle in the present application. DETAILED DESCRIPTION

[0073] As shown in Figures 3-9 , the emergency vehicle priority passing control method in the network environment of the present application comprises the following steps:

[0074] S1, collect the basic information of the congested road section in the communication area, including the lane width, the road section length, and determine the road section priority control area;

[0075] S2, enclose the two closest social vehicles in the two lanes in front of the emergency vehicle, and obtain the head lateral distance and the head-tail longitudinal distance of the two enclosed social vehicles, then determine whether the emergency vehicle can pass through the gap formed by the two enclosed social vehicles according to the head lateral distance and the head-tail longitudinal distance, if the emergency vehicle cannot pass through, adjust the speed of the social vehicles, obtain the shortest adjustment time and adjustment speed by calculation, and guide the speed of the enclosed social vehicles accordingly, at this time the emergency vehicle drives at low speed in the speed adjustment stage; if the emergency vehicle can pass through, no speed adjustment is needed for the two enclosed social vehicles, after the social vehicles are guided to the side by the emergency vehicle's own alarm, the emergency vehicle normally straightens through, realizing priority passage;

[0076] Specifically, in step S2, if the two enclosed social vehicles need to be speed adjusted, the following steps are further included:

[0077] S2.1, based on the vehicle state, obtaining the position and speed information of the emergency vehicle and the social vehicles in the control area road section lane;

[0078] S2.2, constructing a double-target constraint model to make the head lateral distance and the head-tail longitudinal distance of the two enclosed social vehicles meet the passage requirements of the emergency vehicle;

[0079] Specifically, the double-target constraint model composed of constraint equations (1)-(6) is constructed, that is:

[0080]

[0081] Where, L gmin represents the minimum head lateral distance; L represents the head-tail longitudinal distance;

[0082] V min represents the lower limit of the adjustment speed of the social vehicle; V max represents the upper limit of the adjustment speed of the social vehicle;

[0083] min means minimization; J is the abbreviation of the objective function, which is often used to represent the objective function in optimal control, that is, for the objective function Take the minimum value;

[0084] represents the speed of the social vehicle i in the left lane in front of the emergency vehicle at t+Δt k ;

[0085] represents the speed of the social vehicle j in the right lane in front of the emergency vehicle at t+Δt k ;

[0086] denotes the position of the i-th social vehicle in the left lane in front of the emergency vehicle at time t + Δt; k

[0087] denotes the position of the j-th social vehicle in the right lane in front of the emergency vehicle at time t + Δt; k

[0088] denotes the position of the i+1-th social vehicle in the left lane in front of the emergency vehicle at time t + Δt; k

[0089] denotes the position of the j+1-th social vehicle in the right lane in front of the emergency vehicle at time t + Δt; k

[0090] Δv i denotes the speed variation of the i-th social vehicle in the left lane in front of the emergency vehicle during the adjustment process;

[0091] Δv j denotes the speed variation of the j-th social vehicle in the right lane in front of the emergency vehicle during the adjustment process;

[0092] Δt k denotes the k-th adjustment time, k ≥ 1;

[0093] Constraints (1) and (2) represent that the adjustment speed of the social vehicle satisfies the upper and lower speed limits;

[0094] Constraint (3) represents that the head-to-tail longitudinal distance satisfies the requirement when the adjustment of the social vehicle is completed;

[0095] Constraints (4) and (5) represent that the two social vehicles in the left and right lanes in front of the emergency vehicle satisfy the minimum head-to-head lateral distance requirement during the adjustment process;

[0096] Constraint (6) represents that if there is no solution, the speed variation Δv i and the speed variation Δv j , then the adjustment time Δt k is increased by one unit of time (since it is a discrete time system, the unit of time for each update is 1), and then substituted into the objective function and constraints (1)-(5) to calculate again. If there is a solution, then go to step S2.3 to update the positions of the emergency vehicle and the social vehicle;

[0097] s.t is the abbreviation of subject to in linear programming, used before the constraint condition;

[0098] ​​​​S2.3, updating the positions of the emergency vehicle and the social vehicles according to the vehicle state transition;

[0099] Specifically, in step S2.3, the vehicle state transition calculation formula is:

[0100]

[0101] wherein, represents the position of the social vehicle i in the left lane in front of the emergency vehicle at time t;

[0102] represents the position of the social vehicle j in the right lane in front of the emergency vehicle at time t;

[0103] represents the speed of the social vehicle i in the left lane in front of the emergency vehicle at time t;

[0104] represents the speed of the social vehicle j in the right lane in front of the emergency vehicle at time t;

[0105] y(t+1) represents the position of the emergency vehicle at time t+1; y(t) represents the position of the emergency vehicle at time t;

[0106] V E represents the driving speed of the emergency vehicle;

[0107] According to the constructed double-target constraint model, speed guidance is performed, which is described in the following embodiments:

[0108] First speed adjustment is performed:

[0109] In the first iteration, it is assumed that the initial Δt1=0, which means that the initial time of the first adjustment is 0;

[0110] Substitute Δt1=0 into the objective function and constraint equations (1)-(5);

[0111] If the speed change Δv i , the speed change Δv j can be solved, the iteration stops, and at this time Δt1=0;

[0112] If it cannot be solved, the second iteration is entered;

[0113] In the second iteration, take Δt1=0+1=1, and substitute Δt1=1 into the objective function and constraint equations (1)-(5) again;

[0114] If the speed change Δv i , the speed change Δv jIf yes, then iteration stops, at this time Δt1=1;

[0115] If no, then enter third iteration;

[0116] Repeat the above iteration operation until the speed change Δv i , the speed change Δv j is solved.

[0117] S3, after the adjustment, the emergency vehicle resumes the original speed until passing through the two social vehicles, and then repeats the step S2, that is, detects again whether the speed adjustment is needed, and when the speed adjustment is needed, repeats the iteration operation in the above speed adjustment process to complete the corresponding number of speed adjustments until the emergency vehicle drives off the congestion road and obtains the shortest travel time of the emergency vehicle through the congestion road.

[0118] Further, in step S3, further includes:

[0119] After the speed adjustment of the social vehicle is completed, the emergency vehicle resumes the original speed for a unit time, and then updates the travel time of the emergency vehicle as:

[0120] t=t+Δt k +1

[0121] Then, the adjustment time Δt k , the speed change Δv i , the speed change Δv j obtained by iteration through the double target constraint model is substituted into the state transition equation y(t+1) of the emergency vehicle, and then it is judged whether the emergency vehicle drives off the congestion road.

[0122] Further, the judgment formula for the emergency vehicle driving off the congestion road is y(t)≥l,

[0123] If the judgment formula is satisfied, it means that the emergency vehicle has driven off the congestion road, and according to the formula:

[0124] min t=arg[y(t)]

[0125] The shortest travel time of the emergency vehicle through the congestion road is obtained.

[0126] Wherein, arg represents the inverse function.

[0127] The target function of the travel time is t=arg[y(t)], that is, the minimum value of the target function of the travel time is the shortest travel time.

[0128] If the judgment formula is not satisfied, it indicates that the emergency vehicle has not left the congested road section, and then the updated emergency vehicle travel time value is substituted into the double-target constraint model of step S2.2 for repeated detection and adjustment.

[0129] Wherein, l represents the length of the congested road section.

[0130] In the present application, when the emergency vehicle needs to pass through a certain congested road section, the travel time of the emergency vehicle can be predicted, and the speed of the social vehicle is adjusted by guiding the social vehicle to give way to the emergency vehicle in the shortest possible time to supply the emergency vehicle to bypass through.

[0131] The present application is described in the following embodiments, and the following table is the predicted travel time of the emergency vehicle under different density states, and the corresponding verification is carried out:

[0132]

[0133] In the above table, case one is explained and described in the high density state:

[0134] A 2-kilometer long one-way two-lane road section is selected, and the existing software python is used for simulation. The vehicles arrive in accordance with Poisson distribution, and the average vehicle headway (here, the vehicle headway refers to the distance between the vehicle heads of the front and rear two social vehicles in a single lane) is 25.6m. Finally, 154 vehicles are generated on the 2-kilometer two-lane road section, so the single lane density is 39 vehicles / km, and it is used as a high density state;

[0135] The initial spacing in the table refers to the longitudinal spacing (i.e. the distance between the vehicle heads of the first vehicle in the left lane and the first vehicle in the right lane) of the first vehicle in the left lane and the first vehicle in the right lane on the congested road section at the initial time (t=0). For example, when the initial spacing is 7m, the shortest travel time of the emergency vehicle is 200s;

[0136] Figure 8 is the space-time diagram when the initial spacing is 38m in the present application embodiment (case four), Figure 8The part indicated by the black arrow is a zoomed-in view of the part; the black solid line in the figure represents a left-side social vehicle, the black dashed line represents a right-side social vehicle, and the red solid line represents the emergency vehicle; the two social vehicles in front of the emergency vehicle are guided to adjust the speed, the magenta line represents the change in speed of the right-side social vehicle, the slope of the magenta line is the adjusted speed, and the blue line represents the change in speed of the left-side vehicle; as shown by the magenta line and the blue line, the slope of the social vehicle in the time-space diagram changes, which indicates that the social vehicle is successfully controlled, and it can be shown that the control effect of the social vehicle by the control method of the application is obvious, and the problem of insufficient transverse spacing in front of the emergency vehicle can be quickly solved.

[0137] The density unevenness (high on the left and medium on the right) in case four refers to a high-density state on the left lane and a medium-density state on the right lane.

[0138] Figure 9 The abscissa in the figure represents the initial spacing of the social vehicle, and the ordinate represents the travel time of the emergency vehicle. Figure 9 As shown in the figure, in the high-density state, the travel time of the emergency vehicle is not affected by the initial spacing; in the medium-density and low-density states, the larger the initial spacing, the shorter the travel time of the emergency vehicle; therefore, the priority passage control method of the application can be applied to various density states.

[0139] Figure 4 is a schematic diagram of the emergency vehicle normally straight through after the two social vehicles in front of the emergency vehicle are guided to drive on the side by the emergency vehicle's own alarm in the case that the transverse spacing of the two social vehicles is sufficient (in this case, speed adjustment is not required);

[0140] Figure 5 is a schematic diagram of the social vehicle circle in front of the emergency vehicle in the case that the transverse spacing of the two social vehicles in front of the emergency vehicle is insufficient; the two social vehicles in the square in the figure are the two social vehicles in the circle;

[0141] Figure 6 is a schematic diagram of the speed guidance of the two social vehicles in the circle in the case that the transverse spacing of the two social vehicles in front of the emergency vehicle is insufficient, so as to leave sufficient spacing for the emergency vehicle to pass through;

[0142] Figure 7 is a schematic diagram of the emergency vehicle passing through after the two social vehicles in the circle leave sufficient spacing in the case that the transverse spacing of the two social vehicles in front of the emergency vehicle is insufficient.

[0143] It will be obvious to a person skilled in the art that the application is not limited to the details of the foregoing exemplary embodiments and can be implemented in other concrete forms without departing from the spirit or essential characteristics of the application. The embodiments are therefore to be considered in all respects as illustrative and not restrictive, the scope of the application being indicated by the appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein. No reference signs in the claims should be considered as limiting the scope of the claims to the identity of the reference signs therein.

[0144] Furthermore, it should be understood that although the description is made on the basis of the embodiments, not every embodiment contains only one independent technical solution, and the description of the specification is only for the sake of clarity, and those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that those skilled in the art can understand.

Claims

1. A method for controlling priority passage of emergency vehicles in a networked environment, characterized in that: The method comprises the following steps: S1, collecting basic information of a congested road section in a communication area, including lane width and road section length, and determining a priority control area of the road section; S2, circumscribing two closest social vehicles in two lanes in front of the emergency vehicle, and obtaining head-to-head lateral distance and head-to-tail longitudinal distance of the two circumscribed social vehicles, then judging whether the two circumscribed social vehicles need to be guided to adjust speed according to the head-to-head lateral distance and the head-to-tail longitudinal distance, if yes, corresponding speed guidance is performed on the circumscribed social vehicles by calculating the shortest adjustment time and adjustment speed, and in the adjustment process, the emergency vehicle follows at low speed; if no, the emergency vehicle normally alarms to realize priority passing; S3, after the adjustment is completed, the emergency vehicle resumes the original speed and drives until passing the two circumscribed social vehicles, then the step S2 is repeated again until the emergency vehicle drives off the congested road section, and the shortest travel time of the emergency vehicle passing the congested road section is obtained; In the step S2, if the two circumscribed social vehicles need to be adjusted, the method further comprises the following steps: S2.1, based on the vehicle state, obtaining position and speed information of the emergency vehicle and the social vehicles in the control area road section; S2.2, constructing a double-target constraint model to make the head-to-head lateral distance and the head-to-tail longitudinal distance of the two circumscribed social vehicles meet the passing requirements of the emergency vehicle; S2.3, updating the positions of the emergency vehicle and the social vehicles according to the vehicle state transition; In the step S2.2, the double-target constraint model composed of constraint formulas (1)-(6) is constructed, that is: where L gmin represents the minimum lateral distance between the vehicle heads; L represents the longitudinal distance between the head and the tail. V min represents the lower limit of the adjusted speed of the social vehicle; V max represents the upper limit of the adjusted speed of the social vehicle; min is the minimum; J is the abbreviation of the objective function; vi, i, t+Δt represents the speed of the social vehicle i in the lane left in front of the emergency vehicle at the time t+Δt k vi, i, t+Δt represents the speed of the social vehicle i in the lane left in front of the emergency vehicle at the time t+Δt v j(t + Δt) denotes the speed of the social vehicle j located in the right lane in front of the emergency vehicle at the time t + Δt k v j(t + Δt) denotes the speed of the social vehicle j located in the right lane in front of the emergency vehicle at the time t + Δt denotes the position of a social vehicle i in the left lane in front of the emergency vehicle at time t+Δt k t+Δt represents the position of a social vehicle j in the right lane in front of the emergency vehicle at time t+Δt k t+Δt represents the position of the social vehicle i+1 in the left lane in front of the emergency vehicle at time t+Δt k time. represents the position of the social vehicle j+1 in the right lane in front of the emergency vehicle at time t+Δt k time. Δv i represents the speed change amount in the adjustment process of the i-th social vehicle located in the left lane in front of the emergency vehicle; Δv j represents the speed change amount in the jth social vehicle adjustment process in the right lane in front of the emergency vehicle Δt k denotes the kth adjustment time, k ≥ 1; Constraint formulas (1) and (2) represent that the adjustment speed of the social vehicle meets the upper and lower limits of the speed; Constraint formula (3) represents that the head-to-tail longitudinal distance meets the requirements when the adjustment of the social vehicle is completed; Constraint formulas (4) and (5) represent that the two social vehicles in the left and right lanes in front of the emergency vehicle meet the minimum head-to-head lateral distance requirement during the adjustment process; Constraint (6) represents that if there is no solution, the speed change Δv cannot be obtained i , the speed change Δv j , the adjustment time Δt k is increased by one unit of time, and then is substituted into the objective function and constraints (1) to (5) to be calculated again. If there is a solution, the step S2.3 is entered to update the positions of the emergency vehicle and the social vehicles.

2. The method of claim 1, wherein the method comprises: In the step S2, if the two circumscribed social vehicles do not need to be adjusted, the emergency vehicle normally straight passes after the social vehicles are guided to drive on the side through the emergency vehicle alarm.

3. The method of claim 1, wherein the method comprises: In the step S2.3, the vehicle state transition calculation formula is: wherein, represents the position of the social vehicle i in the left lane in front of the emergency vehicle at time t; represents the position of the social vehicle j in the right lane in front of the emergency vehicle at time t; vi, i(t) denotes the speed of the social vehicle i in the lane left of the emergency vehicle at time t; Vj(t) represents the speed of the social vehicle j in the right lane in front of the emergency vehicle at time t; y(t + 1) represents the position of the emergency vehicle at the t+1 time; y(t) represents the position of the emergency vehicle at the t time; V E represents the travel speed of the emergency vehicle.

4. The method of claim 3, wherein the method further comprises: In the step S3, it further comprises: After the speed adjustment of the social vehicle is completed, the emergency vehicle resumes the original speed and drives for a unit time, then the travel time of the emergency vehicle is updated as: t = t + At k +1 Subsequently, the adjustment time Δt obtained by iteration through the dual-objective constraint model k , the speed change amount Δv i , the speed change amount Δv j is substituted into the state transition equation y(t+1) of the emergency vehicle, and it is further determined whether the emergency vehicle has exited the congested road section.

5. The method of claim 4, wherein the method further comprises: The judgment formula for the emergency vehicle driving off the congested road section is y(t)≥l, If the judgment formula is met, it means that the emergency vehicle has driven off the congested road section; If the judgment formula is not met, it means that the emergency vehicle has not driven off the congested road section, then the updated travel time value of the emergency vehicle is substituted into the double-target constraint model in the step S2.2 to repeat the detection and adjustment; Wherein, l represents the length of the congested road section.

6. The method of claim 5, wherein the method further comprises: When the judgment formula for the emergency vehicle driving off the congested road section is met, the shortest travel time of the emergency vehicle passing the congested road section is obtained according to the formula: min t=arg[y(t)] Wherein, arg represents the inverse function. ​

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